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spanielman50
06-23-2009, 10:10 PM
My Two Ski Partners Both Have Mc's. One Has A 2001 And The Other A Gorgeous 2005 Prostar 197. I Thought It Was Horendous When The 2001 Went Through 3 Fuel Pumps In 5 Summers At 800 Bucks A Pop. Now The Worse News Is That It Is Now In The 90's In Upper Michigan And The 2005 Fuel Pump Pukes And We Miss This Whole Week Of Skiing . Will This 2005 Have The Same History As The 2001. Please Advise.

JohnE
06-23-2009, 10:40 PM
First off, no need to capitalize every word. Our resident every word cap is O2B.

The fuel tank should never be run below 1/4 tank as the fuel cools the pump. Search and you will find tons of threads and advice.

jmac197
06-23-2009, 11:27 PM
Page 6-2 of the 2006 manual.....

"Allowing the fuel level in the fuel tank to fall below one-quarter of a tank full may affect the reliability of the fuel pump or result in damage to the fuel pump, which is not covered under warranty.

Ever have deja vu all over again?

spanielman50
06-24-2009, 08:43 AM
thank you for the counsell, he said he had 15 gallons of fuel in tank when it tanked,
are they planning on changing this ?. 800 to 1000 dollars for letting your tank go below 1/3.
sounds like some engineers slept through school. THE CAPS WERE TO MAKE A POINT THAT A 40,000 BOAT SHOULD BE TOUGHER THAN THIS. it won't affect you till it happens to you.

ProStar Slalom
06-24-2009, 08:58 AM
I'll stay out of the debate on whether this is a good design, but can anyone confirm whether I have a pump in the fuel tank? Mine is a 2001, but it's the 19 Skier, not the ProStar. I don't think I have a pump in the tank....at least I hope I don't since I generally run with a max of 1/2 tank to minimize the wake.

meg
06-24-2009, 09:04 AM
My 2006 got below a 1/4 tank a few weeks ago but ran great last wknd (2 days of course I filled it up). If damage occurs to the pump will occurr right away as the tank is below 1/4?

TX.X-30 fan
06-24-2009, 09:20 AM
First off, no need to capitalize every word. Our resident every word cap is O2B.

The fuel tank should never be run below 1/4 tank as the fuel cools the pump. Search and you will find tons of threads and advice.




Would you agree that that stipulation is a crock of sh!t. We need a fix for our boats so we can use them as a boat is intended to be used. My lake has 60 miles of water and 30 of them with no gas so i just stay off all the great water up there??? BULL_CRAP.

MYMC
06-24-2009, 09:32 AM
I'll stay out of the debate on whether this is a good design, but can anyone confirm whether I have a pump in the fuel tank? Mine is a 2001, but it's the 19 Skier, not the ProStar. I don't think I have a pump in the tank....at least I hope I don't since I generally run with a max of 1/2 tank to minimize the wake.
Same system as all other MC's built in 2001...fuel pump is in tank.

My 2006 got below a 1/4 tank a few weeks ago but ran great last wknd (2 days of course I filled it up). If damage occurs to the pump will occurr right away as the tank is below 1/4?
Doesn't seem to happen right away...I tell people "if it fell below a 1/4 tank the pin is out of the grenade."

mccobmd
06-24-2009, 09:33 AM
Meg, My 2006 X1 ran out last year and so far so good. I haven't had a problem yet but others here have had a different experience.

JohnE
06-24-2009, 09:37 AM
thank you for the counsell, he said he had 15 gallons of fuel in tank when it tanked,
are they planning on changing this ?. 800 to 1000 dollars for letting your tank go below 1/3.
sounds like some engineers slept through school. THE CAPS WERE TO MAKE A POINT THAT A 40,000 BOAT SHOULD BE TOUGHER THAN THIS. it won't affect you till it happens to you.


If you typed all caps I'd know you were yelling to make a point. Capitalizing every word just makes it difficult to read. Hopefully it never happens to me, and if it never does it's only because I had a heads up from this place.

JohnE
06-24-2009, 09:39 AM
Would you agree that that stipulation is a crock of sh!t. We need a fix for our boats so we can use them as a boat is intended to be used. My lake has 60 miles of water and 30 of them with no gas so i just stay off all the great water up there??? BULL_CRAP.


I agree it is a crock of sh!t and shouldn't happen. But it's not a big deal for me now that I know about it. It would be a bigger deal if I were on a larger lake like you are. It's a little challenge at csm keeping it over 1/3 tank. big lake and everything is spread out. Ask Tricky.;):D

ProStar Slalom
06-24-2009, 10:16 AM
[QUOTE=MYMC;608802]Same system as all other MC's built in 2001...fuel pump is in tank.


Thanks for clarifying, MYMC. I guess I'll try to keep it between 1/2 and 1/4 instead of between 1/2 and E.

TX.X-30 fan
06-24-2009, 11:24 AM
I agree it is a crock of sh!t and shouldn't happen. But it's not a big deal for me now that I know about it. It would be a bigger deal if I were on a larger lake like you are. It's a little challenge at csm keeping it over 1/3 tank. big lake and everything is spread out. Ask Tricky.;):D




I would think after years of this MC would just want to design a permenant fix so the problem goes away. I would put this on a higher priority list than a camera and hard drive recorder on a boat and all the other goofy stuff (300). :confused:

bigmac
06-24-2009, 12:00 PM
If you typed all caps I'd know you were yelling to make a point. Capitalizing every word just makes it difficult to read.V-bulletin has a an "anti-shout" option that is apparently enabled on this site. If someone tries to type an entire message type in all caps, it often ends up only capitalizing the first letter of each word. Makes the message even more illegible than all-caps, IMHO.

As to fuel pumps, well, what's left to say? We can call it a massive engineering failure, but I'm guessing that MasterCraft is looking at it in terms of the number of complaints and warranty claims they get on the issue. I think they must be aware of it, since they extended the fuel pump warranty from one year to two years, and they did apparently switch to a different type of pump ("Millenium" pump) a couple of years ago. It's supposed to be more robust than the Carters they were using previously.

NoSubstitute
06-24-2009, 12:58 PM
I'm also very frustrated about the fuel pump issue. I did some searching in the Nautique and Malibu sites, and haven't found near the issues that we have. Has anyone thought about doing a "conversion"? What would it take to put one of their fuel pumps into a MC tank? I know there would be some research involved regarding pressure and volume, but I wouldn't think the requirements would be that different.

rodltg2
06-24-2009, 01:04 PM
dont let it ruin a whole week. do a search on this site and you will find instructions including the part # do fix it yourself. when mine went out , i fixed in less than an hour. no loss in ski time. plus its much cheaper. some will argue that its not a good idea to do it. but mine went flawlessly , and it ran fine .

Sodar
06-24-2009, 01:10 PM
dont let it ruin a whole week. do a search on this site and you will find instructions including the part # do fix it yourself. when mine went out , i fixed in less than an hour. no loss in ski time. plus its much cheaper. some will argue that its not a good idea to do it. but mine went flawlessly , and it ran fine .

Exactly! Popping the fuel pump out and swapping for a new pump is easy and easy to get to. Just remove the floor of the ski locker and it is right there.

An issue like this should keep you off the water for a day max.... not a whole week.

TX.X-30 fan
06-24-2009, 07:55 PM
Exactly! Popping the fuel pump out and swapping for a new pump is easy and easy to get to. Just remove the floor of the ski locker and it is right there.

An issue like this should keep you off the water for a day max.... not a whole week.

This is assuming you have a 500 dollar spare pump just hanging around???

TallRedRider
06-24-2009, 11:58 PM
I think I just have to assume that my 90 gallon fuel tank is actually a 65 gallon fuel tank or so....:rolleyes::rolleyes:

The other issue with this is that boat fuel guages are always terrible, and this X45 is no different as far as I can tell. Although I was astonished when I suggested my buddy fuel up his malibu because the tank read a little over 1/2 tank, and we had plenty at the houseboat. He said 'no' the guage is pretty accurate.

Has anyone put in a fuel flow meter? Sure would be nice if I am going to avoid the low fuel issue.

Whitfield
06-25-2009, 07:13 AM
I'm a MC newby, by I've got 20+ years of automotive...

I find this Odd ~ Automotive theory has most all late modle EFi Fuel pumps being equal with their pressure controled by the fuel pressure regulator on the fuel rail (at the injectors) and their volume controlled by injector size and pulse width...

Thus the MC pump should be nothing special other then an over priced automotive knock off dressed up in a special hanger to fit their tank / sender.


ALL late modle automotive EFI pumps suffer the same low fuel lack of cooling fate, but how many folks actually never run their car below 1/4 tank...

Most auto applications you can flick the key multiple times to build initial fuel pressure. By design, the pump only runs first 4 sec until engine start. A weak pump will run the engine but not build enough pressure to start it.

Kingsley X-1
06-25-2009, 07:38 AM
Is this still a problem on the 08s? If so my so called "gernade" must be about to go off. I fill the boat till it is full and run it until it is out then repeat. This is total crap if it causing prematuer wear to the pump.

Whitfield
06-25-2009, 07:45 AM
I'd love to get my hands on a dead MC pump and see what options are available.

Jim@BAWS
06-25-2009, 07:54 AM
My Two Ski Partners Both Have Mc's. One Has A 2001 And The Other A Gorgeous 2005 Prostar 197. I Thought It Was Horendous When The 2001 Went Through 3 Fuel Pumps In 5 Summers At 800 Bucks A Pop. Now The Worse News Is That It Is Now In The 90's In Upper Michigan And The 2005 Fuel Pump Pukes And We Miss This Whole Week Of Skiing . Will This 2005 Have The Same History As The 2001. Please Advise.

Someone is being HOSED on the FUEL PUMP price $800 is about double what the part should cost a retail consumer. (Part only not install) I think if a phone call was placed to the dealer that an appointment could be made to have the pump replaced in a timely manner.

IF you are purchasing fuel dockside at a lake. Contamnated fuel occurs there ALOT more than at a gas station. We had a 2008 MCX in a X-15 that went through 3 fuel pumps in 6 months. THe pumps where warrantied and sent out. WATER IN THE FUEL tank from a dockside filling station was at fault. The pump rusted.

Jim@BAWS

bigmac
06-25-2009, 07:59 AM
I'm a MC newby, by I've got 20+ years of automotive...

I find this Odd ~ Automotive theory has most all late modle EFi Fuel pumps being equal with their pressure controled by the fuel pressure regulator on the fuel rail (at the injectors) and their volume controlled by injector size and pulse width...

Thus the MC pump should be nothing special other then an over priced automotive knock off dressed up in a special hanger to fit their tank / sender.


ALL late modle automotive EFI pumps suffer the same low fuel lack of cooling fate, but how many folks actually never run their car below 1/4 tank...

Most auto applications you can flick the key multiple times to build initial fuel pressure. By design, the pump only runs first 4 sec until engine start. A weak pump will run the engine but not build enough pressure to start it.

People keep wanting to compare this fuel pump issue to the automotive world. The difference is that in the boating world, fuel storage and delivery systems have to meet US Coat Guard requirements. Certainly it's valid to complain about MasterCraft's fuel pump design based on the end result - higher than normal fuel pump failure rate - but I doubt that engineering comparisons to the auto industy are fruitful.

It would be nice if someone from MasterCraft would come on here and explain the problem, but that assumes that they even think a problem exists, and I suspect that their product liability attorneys would strongly advise against a dialogue about a product defect. Just as sure as anything, if they admit the problem, one of us here on Team Talk is going to file a class-action lawsuit.

mccobmd
06-25-2009, 08:09 AM
Is this still a problem on the 08s? If so my so called "gernade" must be about to go off. I fill the boat till it is full and run it until it is out then repeat. This is total crap if it causing prematuer wear to the pump.

I have the 06 X1 and ran it out of gas. My tech at the dealer said that they haven't had nearly as many problems with new fuel pumps FWIW.

spanielman50
06-25-2009, 08:56 AM
drove to minoqua wisconsin to pick up new pump, 120 mile round trip,dealer will install tom. morning so we only lost 3 1/2 days out of five on vacation week. any body have a nautique they want to trade for a 2005 prostar 197

meg
06-25-2009, 09:08 AM
My 06 starts on the first key turn most of the time but will occasionally require me to depress the throttle button and give it a little gas to start-could this be a fuel pump/filter issue or would weak batteries (getting those tested this wknd) be the problem?

Thanks!!!!!

bigmac
06-25-2009, 09:12 AM
drove to minoqua wisconsin to pick up new pump, 120 mile round trip,dealer will install tom. morning so we only lost 3 1/2 days out of five on vacation week. any body have a nautique they want to trade for a 2005 prostar 197

See, there's an example. If the rumors are true, the Millenium pump they'll put in your boat as a replacement will be a much more robust pump than the one that came with the boat.

That assumes that a) there IS such a thing as a Millenium fuel pump. b) the Millenium fuel pump is indeed better than the previous model c) the new replacement pump that you get (we all get with our next fuel pump) IS a Millenium fuel pump (maybe it's only available for new boats).

Illumination from MasterCraft would be nice, so that those of us that have been burned already wouldn't continue to be in the dark, but that's not going to happen. In the meantime, I suspect the problem, real or perceived, will continue to be source of loss of confidence in MasterCraft as a boat brand. At least, on Team Talk it will.

rhsprostar
06-25-2009, 10:13 AM
I'd love to get my hands on a dead MC pump and see what options are available.

Whitfield
I competely agree with you. That's why I put in an aftermarket auto pump and have been running flawlessly for about 75 hours now. I have the old MC pump in my garage if you want it. If you search you will see that Boofer has done a bit of research on the subject as well. I will bump the thread with the replacement info again so that eveyone can dump that crappy MC pump and put in a $100 replacement that will actually work.

Whitfield
06-26-2009, 01:45 AM
Whitfield
I competely agree with you. That's why I put in an aftermarket auto pump and have been running flawlessly for about 75 hours now. I have the old MC pump in my garage if you want it. If you search you will see that Boofer has done a bit of research on the subject as well. I will bump the thread with the replacement info again so that eveyone can dump that crappy MC pump and put in a $100 replacement that will actually work.

Thanks rhsprostar,

Looks like you guys have the aftermarket pump application well covered. With the pump sealed in the tank their is No Marine Fuel Safety System involved, the specs for EFI pump operation do not change just because it is in a boat fuel tank.

Now more on Marine EFI theory and the death of the pump....

Jim at BAWS is right on target... Stations with less traffic (marinias) will create and sell stale fuel due to lack of turn over excessive condensation. A fuel pump in your boat sitting (Not used daily) in a bath of stale fuel / water will be the death of most any EFI pump but a lesser pump will die a faster death.

This new ethenol based fuel is only making the water issue worse... Generally fuel not used in 90 days is at risk. Here is a great read on the new FUEL PROBLEM some of which is helping to kill the pumps.

http://www.fuel-testers.com/marine_boat_ethanol_problems.html


THe pumps where warrantied and sent out. WATER IN THE FUEL tank from a dockside filling station was at fault. The pump rusted. Jim@BAWS
[I]If most are dieing due to water / rust, then I wonder if a few oz of two stroke oil as a fuel conditioner would help save the pump...

Whitfield
06-26-2009, 01:54 AM
While smoking this over I've come up with another concern / question...

Most automotive applications now run a sealed and pressurized fuel tank system as part of the evaporative emissions package. This helps to keep the fuel from evaporating to the atmosphere and also prevents moisture from the atmosphere from entering the tank. Thus the Check Eninge light will come on if you leave the fuel cap off / loose...

Do the EFI MC's run a pressurized fuel tank. If not the issue can be compounded by absorbing moisture from the atmosphere as well as in tank condensation.

bigmac
06-26-2009, 07:25 AM
No, it's a fuel vented tank, per USCG requirments.

TX.X-30 fan
06-26-2009, 07:52 AM
Whitfield
I competely agree with you. That's why I put in an aftermarket auto pump and have been running flawlessly for about 75 hours now. I have the old MC pump in my garage if you want it. If you search you will see that Boofer has done a bit of research on the subject as well. I will bump the thread with the replacement info again so that eveyone can dump that crappy MC pump and put in a $100 replacement that will actually work.

I want to do this???? What boat and motor?

rhsprostar
06-26-2009, 08:42 AM
I want to do this???? What boat and motor?

TX.X-30 fan
I am not sure about what you are asking...my boat is an PS197 with the LQ9 but they all use the same actual pump as far as i can see. Only the module is different because each boat has a different shape gas tank.

JimN
06-26-2009, 08:47 AM
While smoking this over I've come up with another concern / question...

Most automotive applications now run a sealed and pressurized fuel tank system as part of the evaporative emissions package. This helps to keep the fuel from evaporating to the atmosphere and also prevents moisture from the atmosphere from entering the tank. Thus the Check Eninge light will come on if you leave the fuel cap off / loose...

Do the EFI MC's run a pressurized fuel tank. If not the issue can be compounded by absorbing moisture from the atmosphere as well as in tank condensation.

No, it's vented. It was hard enough to get the Coast Guard to allow in-tank pump use at all but they (the CG) would never see the benefit if anyone suggested pressurizing the tank. They couldn't understand why anyone would want to put the pump in the tank and the only reason they got the message was because Alan told them that he had been testing it that way for a few years before the meetings. The CG isn't exactly up to speed on newer technologies for boats like these and the ones who were making the decisions were like boulders in the road- just in the way.

Whitfield
06-26-2009, 09:06 AM
Vented tank + e10 + use on water...

WoW! 8( Just WoW....

It is no wonder they even run at all.

And I always thought the California Emission Natzi's were crazy... I'm suprised that the USCG is so far behind.

This is another BIG and OBVIOUS reason for fuel pump death and poor fuel quality.

Government mandates Ethenol enhanced fuel that absorbs water like a sponge A N D The Government mandates boat tanks to be used on water vented to the atmosphere.

How can the USCG mandate a sub standard fuel systems that bleeds off evaporative emissons to the environment and absorbs water / degrades fuel. Just how much would it really take to sway them. With the go green stance of todays government.

I understand the complications of a boat fuel tank / in a unvented hull / = BomB

But their is a better way and the technolodgy is already here. THe Mfg's are actually stripping it away to meet the USCG requirements...

Whitfield
06-26-2009, 09:19 AM
JimN you seem to have intiment knowledge of the subject.

The weight of the world and the overwealming majority of governmnet is against them, it shouldn't be that difficult to steer them to our side.


So just thinking out loud again....

even in stupid simple terms ~ Run a pressurized inner tank with an externally vented outer shell per current USCG safety requirments.

Set up the tank pressure switch logic based on current automotive perameters, Loss of tank pressure or fuel present in the outer shell place the vessle's computer in limp mode set the Service light ect... But would still avoid the big boom.

Obviously they have already overcome the fuel injector leaking externally hurdle... That would be my greatest big boom concern.

JimN
06-26-2009, 01:11 PM
JimN you seem to have intiment knowledge of the subject.

So just thinking out loud again....

even in stupid simple terms ~ Run a pressurized inner tank with an externally vented outer shell per current USCG safety requirments.

Set up the tank pressure switch logic based on current automotive perameters, Loss of tank pressure or fuel present in the outer shell place the vessle's computer in limp mode set the Service light ect... But would still avoid the big boom.

Obviously they have already overcome the fuel injector leaking externally hurdle... That would be my greatest big boom concern.

What external fuel injector leaking are you referring to? I have never heard of a single case in a boat.

"The weight of the world and the overwealming majority of governmnet is against them, it shouldn't be that difficult to steer them to our side."

Who, the Coast Guard? They don't care who's on their side, they just like to tell people that a new way won't work. They have the authority over our waterways and they know it, regardless of whether a new way is better, or not. It's not hard for a weekend warrior servicing their own boat to burn it to the water, which I saw happening last summer. I will assume he did some bad wiring or fuel line work to cause it, or overheated the crap out of it.

IMO, and I mentioned it before, a raised chamber in the tank that houses the main pump would help this, especially if they used some kind of low pressure pump to fill that chamber. This way, the pump would always be immersed in fuel, unless the tank is truly empty. Part of the equation needs to allow for the fact that when a tank that covers so much area is low, a given volume is awfully shallow. Also, with gasoline's viscosity being what it is, this won't be so easy with a molded tank.

Whitfield
06-26-2009, 08:14 PM
I think a good first step is to determine what killed the pump in each case. It is difficult to cure if you do not determine the exact cause.

AS Jim said rust killed the few he spoke of. Rust is a direct result of water contamination. Water contamination is common in todays E-10 Fuel. E-10 (fuel with 10% ethenol) is all I have available here in Virginia. In E-10 fuel and water will mix, water will not be in a seperate pocket floating around the bottom of the tank as in years past.

Most of todays EFI in tank pumps can run 2 min+ dry before overheating failure. Once removed and taken apart overheating signs should be obvious damaged brushes / windings / plastic disfiguration ect...


As far as leaking injectors comment... I have yet to see any leaking on a boat, the USCG and the mfg's have done a superb job at keeping that under control. It was just to say that I fear the injectors greater then a leaking tank. I think that the fuel rail to the injector connection and the injector itself is the weakest link (most succeptable to leak) in the closed / pressurized EFI system.

erkoehler
06-26-2009, 09:58 PM
I'll drive from Chicago to change that fuel pump if you'll pay me $1,000! I'll bring the part and swap it in the garage/on the lift.

:D

Footin
06-26-2009, 10:02 PM
I'll drive from Chicago to change that fuel pump if you'll pay me $1,000! I'll bring the part and swap it in the garage/on the lift.

:D

Boat sales must be slow, he'll do anything for a buck!

erkoehler
06-26-2009, 10:03 PM
Boat sales must be slow, he'll do anything for a buck!

Thats way more than a buck :)

Plus, make it a business trip and hang out at the cabin for the weekend :)

JimN
06-26-2009, 10:13 PM
I think a good first step is to determine what killed the pump in each case. It is difficult to cure if you do not determine the exact cause.

AS Jim said rust killed the few he spoke of. Rust is a direct result of water contamination. Water contamination is common in todays E-10 Fuel. E-10 (fuel with 10% ethenol) is all I have available here in Virginia. In E-10 fuel and water will mix, water will not be in a seperate pocket floating around the bottom of the tank as in years past.

Most of todays EFI in tank pumps can run 2 min+ dry before overheating failure. Once removed and taken apart overheating signs should be obvious damaged brushes / windings / plastic disfiguration ect...


As far as leaking injectors comment... I have yet to see any leaking on a boat, the USCG and the mfg's have done a superb job at keeping that under control. It was just to say that I fear the injectors greater then a leaking tank. I think that the fuel rail to the injector connection and the injector itself is the weakest link (most succeptable to leak) in the closed / pressurized EFI system.

I'm not sure where the rust would come from- the tank is plastic, the fuel lines are Teflon/stainless mesh/fiberglass mesh/non-flammable jacket, the metal lines are stainless (IIRC) and the injectors usually don't have much trouble with this stuff. I'm in the Milwaukee area and we get humid garbage weather a lot with E-10 and I have never had a problem with my truck running on it. No fuel line freezing, no bad idle, no bad pump or anything.

Re: the USCG or manufacturers doing anything to keepo injectors from being a problem- they buy the motros from GM and make a few changes but really, they're pretty much off the shelf. GM is who does the job of keeping injector failure to a minimum.

Whitfield
06-26-2009, 11:06 PM
A good read on GM fuel pump failure diagnosis. . . (Automotive)


http://www.asashop.org/autoinc/jan98/techtotech.htm


Diagnosing Electric Fuel Pumps Using a Current Probe
Posted 1/20/1998
By Jeff Bach

Testing a fuel pump with an oscilloscope may sound like overkill when you first hear it, but if you look closer you will see why I have opted to use this method over pressure and volume testing.

Typical roller vane type automotive fuel pumps (running loaded) draw between three and six amps at 5,000 to 6,000 rpms (approximately) when they are new. They are designed to have a useful life expectancy that will usually take them just beyond the warranty period. Unfortunately, they do not just roll over and die in their final days. Generally, they start to fail in one of three ways: brush, armature or bushing wear. When the brush material wears away, the spring tension lessens, increasing the resistance at the brush contact point on the armature. The increased resistance lowers the current flow, slowing the fuel pump speed. Symptoms may include surging, low power (especially on hills), hard starting cold, hard restarting hot (usually with less than half a tank of fuel), rough idling, dying at stops, etc. Replacing the fuel filter at this point will generally give temporary relief from some of these symptoms. The fuel pump will usually pass a pressure test at this point and may or may not pass a volume test. This is perhaps one of the most misdiagnosed conditions a car may have. Figure 1 is a waveform from a fuel pump in this borderline condition.

This one came from a 1989 Chevy Astro 4.3 liter Vortex engine. The complaint was "hard starting cold." The owner thought it might have something to do with the radio drawing the battery down because he could get it to start with a jump. The battery was less than a year old. He had determined that not enough voltage was getting to the computer or module after sitting overnight. He had already tuned the engine, replaced the oxygen and MAP sensors, TPS, coolant sensor, cap, rotor, wires, plugs, fuel and air filters, ignition module and ECM. He said it had good fuel pressure (58 psi), and if I could just find out what was draining the battery overnight, he was sure that would fix it.

After not finding an electrical system drain, and test-driving the vehicle (which ran fine on the highway), I let it stand overnight. Sure enough, the next day it would crank fine but would not hit a lick. I tested the battery voltage to see if the owner's theory had any merit and found it to be cranking at 11.6 volts. I connected an ST 125 spark tester to a plug wire and cranked the engine again. It had a good spark. I connected the scan tool and found no codes and the presence of a cranking rpm signal. Being of sufficient experience not to rely totally on test results gathered by DIYers, I did my own fuel pressure test. It had 56 psi at key-on. It looked OK to me (not being familiar with this engine at the time). Since the injector is buried under the intake on this model, I couldn't get to it to observe a fuel spray. I thought I would try the owner's suggestion of jumping it just for the heck of it and it started right up. I shut it off and disconnected the cables. It restarted and ran fine. I could not get it to duplicate the hard starting condition so I thought I would try to duplicate the battery condition. I turned the headlights on and let it stand for not more than two minutes and it failed to start again. I noticed that the fuel pressure was 52 psi cranking when it would not start, and when I hooked up the cables it went up to 54 psi when it would start, then up to 56 while it was running.

Could this slight difference in fuel pressure keep this engine from starting? Surely not. I deadheaded the fuel pump and rechecked the pressure - 60 psi. Was that enough? I was not sure.

I connected my lab scope and amp probe to the fuel pump circuit and collected waveform No. 1 in Figure 1. The DC average was 168 mV, which equals 1.68 amps. I had enough experience with TBI and PFI pumps to know that this was a low reading. Assuming eight armature commutator bars at 2 ms per division, it takes nine divisions to complete eight humps on the waveform pattern (0.018 sec). Divide one by .018 = 55.55 revolutions per second. Multiply that by 60. The pump was running at 3,333 rpms.

I was convinced from my prior research that this was a slow-running pump. I ordered up a new pump and installed it in the tank. After discharging the battery with the headlights for a full 10 minutes, it started every time. The key-on pressure was 56 psi even during cranking. The deadhead pressure buried my 80 psi gauge.

The new pump waveform (waveform No. 2 in Figure 1) revealed an increase in the DC average. It went up to 4.84 amps. The operating frequency of the new pump went up to 5,454 rpms (11 divisions at 1 ms per division to go one revolution; 1/0.011 = 90.9 X 60 = 5,454). Subsequent testing of Vortex fuel pumps has shown 3,333 rpms to be the magic number for a pump exhibiting the "no-start after sitting overnight" condition. The corresponding fuel pressure seems to be 52 psi "no-start," 53 psi "start."

In the two years since I collected the waveforms from this vehicle, I have done extensive research with hundreds of fuel pumps and found about two-thirds fail from the gradual decrease in current flow and subsequent drop in rpms usually exhibiting the first driveability symptoms at just over 3,000 rpms. The other third are the ones that cause the real headaches. They are the ones with complaints of occasional no-starts. There are no particular patterns except they don't seem to ever fail to start in the presence of a technician. They also generally will pass a pressure and volume test. When one of these vehicles is towed to a shop, you can bet it will restart as soon as the wrecker driver sets it down. They cause a lot of unnecessary parts replacement. The frequency of the pump often times is not much less than that of a new one. The average amperage draw usually will be similar to that of a new pump in the early stages.

Figure 2 is a classic example of one of these types of fuel pump failures. The dead giveaway here is the sharp decrease in the current flow in one or more spots on the fuel pump armature pattern. These drops are caused by a spot on the armature where the commutator bar is worn completely away and the brush makes no contact for an instant. If the fuel pump happens to stop on the spot, the result is usually a no-start until the fuel pump cools off or is vibrated. Generally, there will not be any other driveability complaint in the early stages of this type of failure.

This particular pattern came from a 1989 Chevy Blazer owned by my cousin. He called me one Saturday from his cell phone. He was fishing at a remote lake in Indian Creek Reserve when his vehicle failed to start. He was attempting to remove the tank in a gravel parking lot based on the fact that he could not hear the fuel pump running when he cycled the key. He had the tank partially dropped when he realized that the job was a bit more than he had anticipated and he was not 100 percent sure of his diagnosis. He called me to find out if there were any tricks to dropping the tank. I quizzed him about the symptoms and told him to try to start the truck. I told him if it started, to re-secure the tank and drive it to the shop where I would test it for him. When he arrived at the shop, he informed me that it had failed to start for his wife at the grocery store one day a couple of weeks ago. He said that when he got there it fired right up and had not acted up again until today. I nonchalantly went for my scope and probe and connected them to the fuel pump circuit. I collected the lower waveform in Figure 2 while reminiscing with my cousin about the good old days. He followed me to my computer where I downloaded his fuel pump wave to my software program. I typed the words "bad pump" in the data box and dragged it down to his waveform. My cousin got quiet for a few minutes while staring intently at the screen and finally said, "What the heck are you doing?" At that point, I was happy to fill him in on the new technology which led me to my unshakable conclusion that his fuel pump was responsible for the intermittent problem he was having.

After replacing the pump, I took the new pump wave in Figure 2 and showed him the difference. I explained that the low spots were caused by a bad spot on the armature and dissected the pump to show him. Sure enough, there was an obvious place on the armature where the commutator bar had worn completely through. My cousin was spellbound and requested a copy of the waveforms, which I was happy to provide him. He called me later to let me know that although he had not noticed any loss of power prior to replacing the pump, he did notice that it ran a lot better with the new one.

This test method has proved itself time and again to be the best way to check fuel pumps - so much so that I seldom get out my fuel pressure gauge.

The current probe has enabled me to turn tough to find intermittent problems into routine maintenance (Crocodile Lemonade). I test fuel pumps like I look at brake pads. How much life is left in it? And should I recommend replacement yet?

I like to print a copy of the customer's fuel pump wave and a new one so I can show them the difference. Once they authorize the repair, I print another with their new and old pump. Of course, one of the most popular questions I get asked is, "Do you mind if I take this to show to my husband?" Figure 3.