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bfrank
07-02-2006, 12:51 AM
I have been having problems with my 1996 prostar 190 LT-1. Will not run (bogs down) above about 2800 RPM. Read some earlier threads suggesting to check the anti siphon valve and screens on fuel pump. My question is: Can a fuel pump overheat from blockage, be cleared out and expected to funtion properly again or is it crap when it gets to this stressed out point? Has anyone cleaned out the fuel pump screens with success?

I am going to check my screens and antisiphon valve first because I priced out a fuel pump from a to be unnammed Mastercraft dealer that really was less then cordial, if you get my drift (lost my business from attitude alone).

Anyone know where other then MC dealer to purchase a fuel pump where I wont get screwing? Or at least less of one, if I find I do need one?

Thanks, this board is great!! :twocents:

Farmer Ted
07-02-2006, 12:58 AM
have you changed both fuel filters?

when I un-winterized this spring the engine idled fine but any time the throttle was moved out of the detent the engine would bog down and die

I replaced both filters and it runs like a champ.

just saying it might be a quick and easy (cheap) fix

bfrank
07-02-2006, 01:03 AM
Which filters are you referring to? Tank or inline? Or both? Havent dug in yet to even know what is there.

John B
07-02-2006, 01:10 AM
Does it do it all the time? Or just after it has been warmed up?

bfrank
07-02-2006, 01:15 AM
More so when warmed up. But pretty constant. You can kind of goose the throttle back and forth when cold and get a little bit more response.

John B
07-02-2006, 01:17 AM
I had that happen to me(same boat same motor) It was overheating. The LT1 has a RPM reducer.I had a bad impeller.

bfrank
07-02-2006, 01:20 AM
Temp is running a cool 160 degrees. 180 at startup after running. Changed both thermostats last season. Seems fuel starved, but certainly could be wrong.

John B
07-02-2006, 01:25 AM
When was the last time you changed your impeller?

Farmer Ted
07-02-2006, 01:29 AM
Which filters are you referring to? Tank or inline? Or both? Havent dug in yet to even know what is there.


there's one that is at the top of the fuel tank and another one on the engine

bfrank
07-02-2006, 01:31 AM
end of last season (25 hrs past). If I was having an overheating problem, wouldn't it show on the temp?

bfrank
07-02-2006, 01:32 AM
thanks, anti siphon location?

John B
07-02-2006, 01:33 AM
When it was happening in my boat. I though it was fuel too.I change the fuel filter,Pull the tank looked for blockage. Then impeller came apart.

bfrank
07-02-2006, 01:34 AM
Any abnormal temps? Or was everything reading fine?

bfrank
07-02-2006, 01:40 AM
Mastercraft owners are wayward engineers. You guys like puzzles, or at least have to deal with them. I love it in a disturbing way. Thanks in advance, because I will find the problem adventually, and do appreciate the help!

bfrank
07-02-2006, 01:41 AM
eventually

John B
07-02-2006, 01:42 AM
If there is no water going though to motor the thermostats can't read right.

bfrank
07-02-2006, 01:44 AM
I will give it a try (impeller), certainly can't hurt.

Foiler
07-02-2006, 01:57 AM
My 93 LT-1 had a similar problem, I had a fuel pressure test done and we thought sure it was the pump. After I replaced the pump same problem.

After some good advice from here I found the problem. There are fittings where the gas lines attach to the tank, I took the lines off then unscrewed the fittings and found the blockage.

Now I have an extra pump, not sure about your newer boat set up but it might be worth a shot. Make sure you unscrew the fittings from the tank to see if there is anything blocking the gas line.
.

bfrank
07-02-2006, 02:04 AM
That is what I heard about too. I guess I have some work ahead of me starting with the cheapest and working my way forward. Impeller, fuel filters, anti siphon valve, fuel pump... winter!!!

John B
07-02-2006, 02:06 AM
There is also a screen in the bottom of the fuel pump.

tommcat
07-03-2006, 09:56 AM
my 97 had similiar problems. i had some debris in the tank clogging the pick up screen and also seem to have some stuff in the fuel lines that clogged the screen in the pump.
i cleaned them both out and it was fine. the pump put out full flow and pressure after so i dont think you damaged the pump unless you ran it for a really long time like that.

bfrank
07-03-2006, 12:00 PM
Thanks for the info guys. I will dig in this week. I feel a little bit stupid, I just replaced the sending unit a month ago. May be loosened some crap in the process. Now I know, when you have access to the tank CLEAN IT! Electronic sending unit works great (after a failed attempt to repair old one) Pulled the boat apart twice!!

bfrank
08-07-2006, 12:26 PM
Ok, got the boat on the water a few times. Back to thinking that it is the fuel pump. Cleaned and checked all fuel lines, antisiphon valve, checked for obstructions at fuel tank, changed filters at tank and inline.

Runs great for about an hour or so, then after consistant running lose my higher RPM's (above 2500). Let sit for 10 or 15 minutes, fine again for another 15 minutes or so. Repeats cycle. Engine temp is perfect 160 degrees. Temp guage works fine. Is this the effects of an electronic fuel pump going bad? (mounted on side of motor) Running out of options...

JimN
08-07-2006, 12:43 PM
" Is this the effects of an electronic fuel pump going bad?"

This depends on whether you checked the screen on the pump and are measuring the fuel pressure when the problem occurs, seeing low pressure. I assume you have taken multiple fuel samples and checked the pressure at more than just idle. It needs to be checked at key ON, idle, 2000RPM and at WOT. There's really no other valid way to test it since the problem occurs after running it hard for awhile.

If the motor loses RPM and runs lumpy, it could be in RPM reduction (DO NOT RUN IT IF THIS HAPPENS!). If the oil cooler hasn't been checked/cleaned, do that now. If you're not the first owner of this boat, consider the fact that the fuel pump may have been run dry at least one time more than it really needed (which is none) and the impeller is going bad. It shouldn't take 15 minutes to get back to normal if it's the pump. Next time, shut it down and wait for more than 5 seconds before turning the key to ON to let the pump prime. Turn the key OFF for more than 5 seconds and try to start it. If it starts immediately and goes to full RPM range, it's in the fuel system. If it runs lumpy and still doesn't go to full RPM, it could be a cooling issue. Pat your hand on the exhaust manifold risers after a long run and see if they're too hot to touch after idling for about 15 seconds. They should be cooled after this amount of time. If you notice one is always hotter than the other, it's a cooling system issue and needs to be dealt with.

bfrank
08-07-2006, 01:49 PM
Thanks Jim, Pretty sure it is not a cooling issue, as I have dealt with this in the past. I bought the boat with a few problems. I know that the boat was run hot in the past and have heard that this will kill an electronic fuel pump quicker then all. I am not running in limp mode as I have experienced this before and know the sinking feeling... The boat just needs moments of rest to restart and run at full RPM for a short period of time. Is this a symptom of a failing pump? Are they intermmitent, capable of working for a while then failing at higher RPM's, then working again? I am not able to do any type of pressure test as for lack of equipment and skill?!?

Jim@BAWS
08-07-2006, 02:11 PM
thanks, anti siphon location?

The ANTI SIPHON is on top of the fuel tank. A 90 deg elbow with a ball check valve. It is where the FUEL line comes out of the tank. If anything foriegn is in the tank it might have gotten caught in that valve. Also OLD gas tank plastic shavings may have gotten caught in that valve. There are alot if sensors on that motor IAC MAP etc. Sometimes it is best to have a certified dealer hook that motor up to a TECH 1 and check for codes.
Lastly check the TOP of your fuel pump. There is a SCREEN on top
Gp ahead and remove that screen, If the pump is screaming or making a funny noice that will sometimes take care of the problem.

Jim@BAWS

JimN
08-07-2006, 04:43 PM
The fuel pressure test is actually pretty easy. Sears and some other auto parts stores sell a gauge with a release valve on it (that's the kind you want). There's a black plastic cap on the fuel line and inside of this, is a valve like a tire valve. Never attach the gauge when the motor is running- the pressure can cause fuel to squirt and it's a fire and safety hazard. Thread the hose on and turn the key to ON, then put the end of the clear hose in a bottle so you can press the valve button to get rid of any air in the gauge. Turn the key ON again and look at the gauge, writing the number down. Next, start the motor so you can take a reading, writing the number down. The 2000RPM and WOT tests need a second person, preferably, and the boat really needs to be driven so the motor has the normal load on it.. Your pressure needs to be in the 30 pound range, maybe a little higher. If it's less than 25, you have a restriction, clog or a bad pump.

After running the boat on the water, with the motor running, put the end of the clear hose in a bottle press the button so you can collect some gas. I use a clean, clear plastic Pepsi bottle and keep the cap with it so I can close it. 20 oz is fine for this. Use whatever brand you prefer, just make sure it's clear and clean.

Not only should codes be checked, they should look at the data from the sensors, the voltage should be checked (low voltage can indicate a bad ground or power lead), the IAC should be reset and functioned and a snapshot should be taken. Everything should be well documented for you. They can print a copy of the snapshot for you, too.

bfrank
08-07-2006, 07:37 PM
Thanks Jim, I will follow up when I get a chance to work on my boat..

tommcat
08-07-2006, 09:43 PM
The ANTI SIPHON is on top of the fuel tank. A 90 deg elbow with a ball check valve. It is where the FUEL line comes out of the tank. If anything foriegn is in the tank it might have gotten caught in that valve. Also OLD gas tank plastic shavings may have gotten caught in that valve. There are alot if sensors on that motor IAC MAP etc. Sometimes it is best to have a certified dealer hook that motor up to a TECH 1 and check for codes.
Lastly check the TOP of your fuel pump. There is a SCREEN on top
Gp ahead and remove that screen, If the pump is screaming or making a funny noice that will sometimes take care of the problem.

Jim@BAWS
jim, i could be having a brain malfunction but i swear the screen is on the bottom of my pump, on the inlet side.

tommcat
08-07-2006, 09:44 PM
The ANTI SIPHON is on top of the fuel tank. A 90 deg elbow with a ball check valve. It is where the FUEL line comes out of the tank. If anything foriegn is in the tank it might have gotten caught in that valve. Also OLD gas tank plastic shavings may have gotten caught in that valve. There are alot if sensors on that motor IAC MAP etc. Sometimes it is best to have a certified dealer hook that motor up to a TECH 1 and check for codes.
Lastly check the TOP of your fuel pump. There is a SCREEN on top
Gp ahead and remove that screen, If the pump is screaming or making a funny noice that will sometimes take care of the problem.

Jim@BAWS
jim, i could be having a brain malfunction but i swear the screen is on the bottom of my pump, on the inlet side.

bfrank
10-19-2006, 10:07 PM
Just to finally followup. If gas flows through it, I've been there! It was the $425 fuel pump. Finally ran out of options and changed out the pump. Runs great. I miss the gas mileage that my bad fuel pump gave me, but it runs smoooooth. Funny about the screen discussion. I didn't have any screen on my old pump or new pump.

Thanks for the chatter

JimN
10-19-2006, 11:13 PM
Who is your dealer? $425 sounds high for that pump.

bfrank
10-20-2006, 12:13 PM
Im not sure what happened to my post from yesterday?

But, it was the fuel pump... just to finish up the thread...

bfrank
10-20-2006, 06:13 PM
the pump was $389 +. That was from a Mastercraft Dealer in AZ. Did not want to risk a pump from any other source. That's what one gets for having an LT-1... You can see why I would exhaust all other possibilities first. If it cost $125, I would have changed it out long ago!

Is that an old Les Paul? (curley?)

JimN
10-20-2006, 08:10 PM
Good to hear that it's back up and running.

It's a '59 Relic reissue, but it's from Gibson's version of Custom Shop. It belongs to a friend of mine (www.gregkoch.com). He was using my amp (the Bassman) for a book that'll be coming out in the next month, in time for the shopping season. Tom Wheeler (former editor of Guitar Player Mag) is writing it about Fender amps and when the first tracks were recorded in La Cross, WI they didn't have an original issue Bassman (mine is the original chassis but reissue cab and speakers), a Blackface Twin or a Blackface Super, and those are the amps to the sides of mine. That's really a nice sounding guitar, though.

bfrank
10-20-2006, 09:05 PM
nice... It looks like a curly maple flame top, nice amps as well. Now adays you have to buy a pod or modeling amp to duplicate, though I am a traditionalist (I like old junk)I still have a few guits. I just sold my 59 telecaster a few years back, but still have a 72 flying V, a 68 reissue strat, a 73 precision bass and a few other electrics and a National steel tricone. My brother is friends with Les Paul up in Jersey, and has a standing offer to buy one of his guits, but never has...

JimN
10-20-2006, 09:57 PM
"and has a standing offer to buy one of his guits, but never has..."

He better do it soon. Les is getting up there. Cool thing is, he just signed a 4 record deal a couple of years ago and he's 91. Hopefully, they'll open the Les Paul Museum while he's still alive to see it.

The modeling amps are OK, but the ones that actually use the same or similar circuits are the only way to really nail the sound. Kendrick has one called the New Joy Zee and it has individual circuits for Twin, Marshall 50 Watt, Bassman and Vox AC models, all accessible by switching. Another friend makes stomp boxes and now has a few models of amps that use similar circuits to the greats but he made some changes so they'll be bulletproof. He has been a Fender amp servicer (and most other brands, too) for over 25 years, knows why they break and how to make them not break. His company is RPG Electronics and his pedals are starting to become known in the market. Good guy, too. Has a Gold Top, signed by Les, I think it's a '69. All of the people at guitar shops here who have played through Roger's amps said they kill. I'm going to talk to him about getting a sample so I can show it to people at gigs, so they can find out how good they are and he can sell more of them.

bfrank
10-20-2006, 11:54 PM
Thats pretty cool. I do believe that you need some crap and inconsistant electronics to get original sounds. does your friend have a web site? It sounds worth checking out. I know that a few companies came out with preamps with AU7's(?) to try to overdrive even harmonics, but most sounded like crap. I have a friend (oddly a harvard chemist) that years ago tried to simulate and rebuild my old recording amp which was a 1948 Western Electric with electromagnetic ceramic speaker. (Never made it into production) I got it at an auction at the Christian Science Mother church in Boston about 30 years ago. It was the sweetest distortion that you could imagine. I used it for recording back in the 80's. I have two existing LP's that it is on. My last amp (used in a blues band) NO EFFECTS!!! Was a Altec Lansing 30 amp power amp from the 50's (powered the sound system at the old Charlotte Coliseum), preamped with of all things a Peavy backstage plus practice amp drivin through an old silvertone cabinate with 2 original ceramic speakers and a box with a midrange horn and a few piezeo tweeters. That is a sweet sound. No one can duplicate. It doubled as heat for the practice room. Unfortunatly I do not play out or for that matter, that much anymore but it is a thrill to recall...

bfrank
10-20-2006, 11:57 PM
Les is still gigging in NJ and NJ

JimN
10-21-2006, 01:23 AM
Yeah, he plays every week at a club called 'Iridium', in NYC.

Who did you play and record with?

I don't know if Roger has a site, I haven't seen one but I need to call him, anyway.

It's amazing how the best amps came about- Leo Fender was originally an accountant and bought a repair shop. He had friends who wanted to be heard better in their country bands and he designed amps, probably out of books with audio circuits in them. Odd thing about the Bassman is that they weren't liked for playing bass through, but it became the basis for Marshall and just about all of the class AB amps. The British ones were just made with what they had access to over there, with the higher working voltage.

I haven't tried any of the tube effects because I really don't need them, although for distortion at lower levels, I use a Boss SD-1.

We should probably take this threadjack over to the thread called 'What the pluck?'.