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03geetee
07-02-2012, 11:20 AM
Guys,

Here is the issue I swapped out my fuel filter this year in the spring, I only have one right by the rear of the tank on the passenger side. The fuel line out of the tank 3/8 line runs to this filter (clear with yellow element inside and is directional) then continues all the way to the fuel pump. My question is this is there a specific filter I need here? When I replaced the filter this spring I brought the old one which looked older then sin and they matched it up. I would assume this filter would be full to the brim or at least 3/4 but I am barely getting a 1/4 or less. Whats strange is the boat runs full boar at 44mph and doesnt skip a beat.

My issue is with starting, she doesnt want to start and this has occured out of nowhere. Three pumps in the morning sets the choke and she fires right over. After that all it takes is a flick of the key and shes running, hot or cold. Now I have to pump it, mess with the throttle ect to get it running. Very wierd. Only thing that has me wondering is the filter. Plugs are good, carb isnt leaking fuel into the chambers, distributer is solid, coil brand new less then one season on it, really not sure here.

Any ideas?

JTR

thatsmrmastercraft
07-02-2012, 12:51 PM
Look at the volume of fuel that the accelerator pump is supplying. If your accelerator pump diaphragm is failing, you might no be getting enough fuel for cold start-up. You could have a small clog in one of the nozzles creating a shortage of fuel as well.

If your fuel system can provide enough fuel to run at 44mph, it should provide enough fuel to start properly.

oxberger
07-02-2012, 12:54 PM
There is another filter for the fuel pump. I don't have any pics to post, but its located on the passenger side and is inside the bowl that is attached to the fuel pump. There is a strap with a screw at the bottom of the outside of the bowl that holds the bowl in place. Unscrew that until you can remove the strap and remove the bowl and the filter is right there. It may need to be cleaned. It sounds like after the engine has been off for sometime air is getting into the fuel system and causing the pressure to drop. I hope some of this helps or at least can give you a direction.

03geetee
07-02-2012, 12:57 PM
Look at the volume of fuel that the accelerator pump is supplying. If your accelerator pump diaphragm is failing, you might no be getting enough fuel for cold start-up. You could have a small clog in one of the nozzles creating a shortage of fuel as well.

If your fuel system can provide enough fuel to run at 44mph, it should provide enough fuel to start properly.

Few things to consider I will check it out. Thats what has me stumped she runs like a raped ape up top with that little fuel in the filter? Seems wierd.

JTR

thatsmrmastercraft
07-02-2012, 12:58 PM
Few things to consider I will check it out. Thats what has me stumped she runs like a raped ape up top with that little fuel in the filter? Seems wierd.

JTR

Mine filter isn't always full either.

Philscbx
07-02-2012, 01:12 PM
I would assume this filter would be full to the brim or at least 3/4 but I am barely getting a 1/4 or less.
Whats strange is the boat runs full boar at 44mph and doesnt skip a beat.

My issue is with starting, she doesnt want to start and this has occured out of nowhere.I agree on the Accelerator pump test - and possibly draining reseating the fuel filter can/filter assembly & inspect hose clamps.

The slightest vacuum leak in this zone could pull less fuel.
Apply a little Teflon grease on the threads of can/bolt & seal.
Testing pump pressure to verify as well.

Should have fuel level screw caps to inspect float bowl level -
UPdate - Found info where this may not be true having bowl level screws on Marine Grade Carbs.

Good Luck

ctjahn
07-02-2012, 02:44 PM
Not sure if this applies or not but... Lessons learned the hard way on a racecar... Fuel filter before the mechanical pump didnt work (not enough suction).... When I tried to run it before the pump (logic indicated I wanted to filter before and after the pump - because I am an extra careful guy)


So when I replaced my fuel system last winter (not the pump yet but maybe I should think about it); I put the filter after the pump but before the carb. (yea, the pump will suck the crap from the tank but most have a screen filter in them anyways... The extra filter before the carb allows the filter to catch any debris that may clog jets and such)

ASSUMING it is in the right direction. Cheers to hopefully chasing the right problem!

Cj

thatsmrmastercraft
07-02-2012, 04:01 PM
Not sure if this applies or not but... Lessons learned the hard way on a racecar... Fuel filter before the mechanical pump didnt work (not enough suction).... When I tried to run it before the pump (logic indicated I wanted to filter before and after the pump - because I am an extra careful guy)


So when I replaced my fuel system last winter (not the pump yet but maybe I should think about it); I put the filter after the pump but before the carb. (yea, the pump will suck the crap from the tank but most have a screen filter in them anyways... The extra filter before the carb allows the filter to catch any debris that may clog jets and such)

ASSUMING it is in the right direction. Cheers to hopefully chasing the right problem!

Cj

Good theory which follows through in practice. I have my filter between the pump and the carb. There was nothing on my boat when I got it. The screen at the pump can catch the rocks and trees and allow the filter to catch the small stuff.

thatsmrmastercraft
07-02-2012, 04:02 PM
I agree on the Accelerator pump test - and possibly draining reseating the fuel filter can/filter assembly & inspect hose clamps.

The slightest vacuum leak in this zone could pull less fuel.
Apply a little Teflon grease on the threads of can/bolt & seal.
Testing pump pressure to verify as well.

Should have fuel level screw caps to inspect float bowl level -
UPdate - Found info where this may not be true having bowl level screws on Marine Grade Carbs.

Good Luck

Good catch. As many sources of leaks as possible were removed in the marinization of the Holley carb.

03geetee
07-02-2012, 05:54 PM
Ok good stuff in here I have a 3/8 barb fitting that I am going to replace temporariliy in the filters place to see if that is an issue. The other post from oxberger is interesting I have to look at this to see what he is referring to. Up here for a few more days I will report back.

Thanks guys.

JTR

Philscbx
07-02-2012, 09:58 PM
Found a great view from Holley

http://www.holley.com/data/products/pictures/large0-80492.jpg
http://www.holley.com/0-80492.asp - 600 CFM FOUR BARREL CARBURETOR PART #: 0-80492

03geetee
07-02-2012, 11:33 PM
Okay here we are...

Boat will run at idle or cruising speed as long as you want, then get her up to tow speed 2500rpm and up and within a certain amount of time she dies. No sputter or loss of power just an immediate dead engine. I am thinking the electronic ignition is toast, but I could be wrong. Was on the boat when I bought it have no idea how old so I am going to start there.

Any other ideas? Fuel was not the issue I replaced the old fuel filter with a new clear sight filter and she was 3/4 full the whole time and the carb was spitting fuel with throttle input right before it died. Fuel did not cause it to die I think it is ignition related.

JTR

thatsmrmastercraft
07-02-2012, 11:50 PM
You could potentially check this with a timing light connected and secured so you could run it at speed. Have the trigger held in with a rubber band or duct tape. Have someone watch to see if the light to see what it does as it starts to die. I agree it does sound electrical in nature.

sam196370
07-03-2012, 11:23 AM
Definitely replace electronic ignition parts since they're cheap and set timing. Might also be a clog in the fuel tank somewhere which lets some gas in but not enough to run boat above 2,500. I had an issue with my tank and brought it to radiator shop to clean out and reinforce welded seals.

Will boat run above 2,500 rpm in neutral? If not you could run a fuel line from a portable gas tank to determine whether it's a clog or not.

03geetee
07-03-2012, 12:13 PM
We figured out it is not fuel but I have it narrowed down now I think. I have the original OEM spec electronic ignition upgrade which can be sensitive when the flame thrower II coil is used. When I had coil issues last season I upgraded to the hotter coil which I think is melting my ignition. I talked to the boys at Skidim who have been great in the past and said the older purple and black wire ignition upgrades are suspect to this and that is what I have. So ordered the newer ignitor II which will arrive thursday and I will go from there.

This makes sense to me because the hotter the boat got the faster it would die when you tried to get up to any reasonable speed and RPM. If the boat sat longer it would take longer for the issue to pop up but it always did.

Who knows lets see what happens. Thank you for the help boys.

JTR

oxberger
07-03-2012, 02:26 PM
I hope you get this fixed with the parts you ordered. After the investigation you've done its definately starting to sound more like electronic issues and not fuel related. Keep us posted.

03geetee
07-03-2012, 06:57 PM
Let boat sit all night went out today around noon and brought the volt meter. Boat fired up good, even with some likely fouled plugs from yesterday, and ran strong. Let her idle for a while and ran her up past 2500 and she didnt skip a beat. Shut her off and she fired right back up. Coil had 10 volts or so on the + and - side when grounded to the thermostat housing.

I am pretty confident that when the electronic ignition gets hot something gives just a matter of time and load. My parts should arrive thursday along with new rotor and cap while im at it and I will report back my findings.

JTR

woodnnn
07-04-2012, 05:06 PM
Are you still using the resistor

Sent from my Galaxy Nexus using Tapatalk 2

03geetee
07-04-2012, 09:17 PM
Bypassed per instructions.

JTR

03geetee
07-05-2012, 11:03 AM
Part should arrive soon in the mean time...

-checked antisiphon valve at top of tank, appears fine with no clogs.
-cleaned screen at fuel inlet at carb, few bits here and there but nothing to stop flow in my opinion.
-might turn over motor to verify fuel pumps working but I know fuel isnt the issue because of how black the plugs were from trying to start her after she died.

Will update after the ignition is resinstalled.

JTR

03geetee
07-05-2012, 06:30 PM
She is alive.

Installed new ignition module from pertronix and the boat ran, but like ****. Loosened up the dist and moved it way to far and it took a while to find it again. Ultimately I had to swap in another coil I have laying around because I think this one may have had it. Right now she runs hard, doesnt ping, starts when warm and has not cut out once. I have it timed by ear and instinct but will hit it with a gun when I can.

Right now its time to enjoy the water.

Thanks for all that tried to help.

JTR

mikeg205
07-05-2012, 09:53 PM
Sorry to read about you problems... seems like you're close to a fix.

Philscbx
07-05-2012, 10:02 PM
That was a Mission - Good Job.

Leaving dist just loose enough to barely move by hand - if slight ping is heard - can be retarded slightly should be darn close.

03geetee
07-05-2012, 11:06 PM
That was a Mission - Good Job.

Leaving dist just loose enough to barely move by hand - if slight ping is heard - can be retarded slightly should be darn close.

Yeah she is running damn near close to perfect so I suspect Im within a degree or two. Shes a trooper I still lover her even when she doesnt cooperate sometimes.

JTR

TNPIG
07-06-2012, 09:23 AM
I replaced the fuel line going from my fuel pump to the carb on my 84 S&S. After I did that, the boat wants to stall when I first put it into gear. Does fine at idle and great once I get going, just seems like it wants to die when I first go into gear and start going. Could it be air in the line, or maybe just a coincidence? Seems like it did the same thing when I filled up with gas last time too, but then stopped doing it. I put some of the stabil with ethanol treatment and a half can of sea foam at each fillup, but I can't imagine that would make it want to stall like that. Thanks for any advice

03geetee
07-07-2012, 10:29 PM
I replaced the fuel line going from my fuel pump to the carb on my 84 S&S. After I did that, the boat wants to stall when I first put it into gear. Does fine at idle and great once I get going, just seems like it wants to die when I first go into gear and start going. Could it be air in the line, or maybe just a coincidence? Seems like it did the same thing when I filled up with gas last time too, but then stopped doing it. I put some of the stabil with ethanol treatment and a half can of sea foam at each fillup, but I can't imagine that would make it want to stall like that. Thanks for any advice

I would really try looking at a few things....

-Fuel side remove the fuel line going to the carb, there is a tiny screen in there that might have some junk in it especially since you changed the line. Is it the proper size (the fuel line that is). How is your other fuel filter do you have one in line somewhere?

-Ignition side if your timing is slightly off (points or EI?) this can happen so double check it.

-Also have you replaced plugs and or wires at all are they do?

Just trying to get some information.

JTR

TNPIG
07-09-2012, 09:27 AM
I would really try looking at a few things....

-Fuel side remove the fuel line going to the carb, there is a tiny screen in there that might have some junk in it especially since you changed the line. Is it the proper size (the fuel line that is). How is your other fuel filter do you have one in line somewhere?

-Ignition side if your timing is slightly off (points or EI?) this can happen so double check it.

-Also have you replaced plugs and or wires at all are they do?

Just trying to get some information.

JTR

Where exactly is the screen at on the line? I don't remember seeing one, but I wasn't looking for one either. There looks to be a fuel filter about a foot before the line gets to the fuel pump.

I have the electronic ignition and I haven't changed the plugs since I bought it two years ago.

03geetee
07-09-2012, 11:54 AM
On my holley 4160 there is a brass connection that screws into the carb, this is where my carb attaches to the fuel line coming from the pump. When I unscrew this connection there is a tiny filter inside the carb (smaller then a thimble) that you can remove and clean.

I would change your plugs and see what they look like and the gap, you might have a slight issue causing your hiccup. Start cheap and work your way up.

Try those first and let us know.

JTR