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OSUspenc99
05-14-2007, 10:21 AM
Hello all. I have an 85 S&S that has a 4160 Carb on it. I rebuilt this 2 years ago and didnt really notice any problem. At the end of last year I noticed that it was getting hard to fire up after we switch skiers. Looked at the carb and right after i turn the engine off fuel is still dumping into one side. I told the carb off and took that side bowl off thinking that the float might have been stuck. Adjusted the float a little and then I took it to JEGS high performance where they deal with Carbs all the time. They said that everything looked good.

Had the boat out this weekend and the same thing is going on again. The boat runs fine but it still take 2 long cranks to get it going after switching skiers.

It is also idleing good.


Any ideas here?

MMCCAR12
05-14-2007, 10:37 AM
Having the same problem with my 83SS. I have a low voltage problem when starting. Check the voltage at the 12VDC side of the Balast resistor when the key is on the on position. It should be a strong 12VDC. If it is weak you can jump to the starter relay pin that is not being used. This pin will give you a good 12 VDC when you crank. It is only hot during cranking. If your problem goes away then look at the key switch. This would mean you have a voltage drop in the ignition line. Only jump to the resistor side before the coil, not the coil side.

I did this last weekend and ran it for 3 days. It started on the first crank every time. Im going to change my switch this week.

Good luck

OSUspenc99
05-14-2007, 11:11 AM
Is your still dumping fuel in the carb? You can really smell like the engine is flooded.

OSUspenc99
05-14-2007, 11:13 AM
Also not quite sure where the balast resistor or starter relay switch are to check this. Any help at this point is much needed.

MMCCAR12
05-14-2007, 11:33 AM
Did not have to look at carb. My idles fine, no rich smell. An electrical problem will appear to be a carb problem. You should really not have to pump the gas after droping off a skier. I know that some times a pump works well, but the MC PCM book says you should not have to do it. It is a very easy test to eleminate the voltage/starting issue. Your carb might be Jacked but one step at a time.

OSUspenc99
05-14-2007, 12:21 PM
Thanks for the help but here is my issue. I am not pumping anything to get it to fire. WHen i turn the engine off fuel dumps in the carb without me doing anything other than turning the key off. WHen i try to start it again it is really rich smelling from the fuel that was dumped in before. I will check the electrical but i think this is more of a carb issue.

Any other ideas?

WilliM1940
05-14-2007, 04:54 PM
Dirt in bowl preventing needle from seating, or perhaps a worn inlet valve and seat assembly.

Matt L.
05-14-2007, 05:01 PM
Thanks for the help but here is my issue. I am not pumping anything to get it to fire. WHen i turn the engine off fuel dumps in the carb without me doing anything other than turning the key off. WHen i try to start it again it is really rich smelling from the fuel that was dumped in before. I will check the electrical but i think this is more of a carb issue.

Any other ideas?

Sounds like the venturi(S) aka the round things you see when you look down into the carb from above(above the butterflys).

When my cousin (total gear head & engineer) and I rebuilt mine this year I had a loose one. They will become loose over time causing fuel to dribble out and puddle on the butterflys. At slow speeds it can cause a very low speed stall. Fuel will puddle on the butterflys until you hit the gas. Then it dumps it all in and kills the engine.

We checked it with the carb apart. You use both index fingers, one from the top and one from the bottom and wiggle it back and fourth to see if it moves. if it moves then you may have a leak.

We fixed mine with 2 ballpeen hammers and a block of wood. Put the ball in the back side of the venturi and hit it with the other hammer. This spreads out the end and re-seals it. Other wise you have to replace the center section of the carb.

One place to look anyway.

Later,

Matt

OSUspenc99
05-14-2007, 06:04 PM
Matt,

This is exactly where the fuel is coming from is that venturi. But it doesnt sit on the butterfly because it is open. I think I understand what you are saying to do but you might be getting a PM sometime soon from me. Thanks for the help and I will go from here.

Storm861triple
05-15-2007, 01:26 PM
You have a leaking needle and seat, simple as that. If you're carb is discharging fuel w/the engine off, the needle and seat aren't doing their job (and, you don't have an electrical problem). Replace the needle and seat.

OSUspenc99
05-15-2007, 03:22 PM
Talked with Holley Tech support today and they were very nice and helpful people over there. What he stated was that the only way that fuel is going to come out of that venturi booster is if the bowl is too full or what he called a hot soak issue. He told me to take to bowl off, Flip it over and adjust it up a little bit more and see if I am still having the issue.
I also asked him just for my information if they have a testing center and he stated that they do a flow and repair of any carb for $115 plus parts.
I am not going to resort to that yet.
Here is the number if anyone else might need to call the tech support at holley. 207.781.9741

I will let you know what I find out!

Matt L.
05-15-2007, 10:40 PM
The sitting on the butterfly problem was a car based one. At idle pulling up to the driveway with no pedal at all. then tap pedal to ease up over the curb. That would then open the butterflys up and dump the fuel in and kill it.

Do you have any idle surge issues? That is another symptom of a loose vernuti cluster.

Later,

Matt

Matt L.
05-16-2007, 02:53 AM
Talked with Holley Tech support today and they were very nice and helpful people over there. What he stated was that the only way that fuel is going to come out of that venturi booster is if the bowl is too full or what he called a hot soak issue. He told me to take to bowl off, Flip it over and adjust it up a little bit more and see if I am still having the issue.
I also asked him just for my information if they have a testing center and he stated that they do a flow and repair of any carb for $115 plus parts.
I am not going to resort to that yet.
Here is the number if anyone else might need to call the tech support at holley. 207.781.9741

I will let you know what I find out!

If you look at the venturi cluster it is a pressed fit part that, should it work its way loose over time(and they do), will leak. The pressed fitting on the bowl side is all that holds back the fuel in the bowl.

Leaking/loose venturi clusters are a known Holley problem.

I'm not saying that is your problem, but it could be.

Later,

Matt

Storm861triple
05-16-2007, 03:03 AM
Matt, you're posting some misinformation here.

The fuel level in the bowl SHOULD be lower than the discharge nozzle, and where the discharge nozzle attaches to the bore -the "problem area" that you're talking about- in a properly set up and functioning carb. Even if the OP's nozzles are loose (Something I've never seen in 15 years of wrenching and shop managing), that isn't or shouldn't be causing fuel to flow into the carb bores when the engine isn't running.

Either the float/needle/seat aren't doing their job properly or the fuel pump is applying too much pressure, and is faulty.

Matt L.
05-16-2007, 03:21 AM
Whatever, I've seen them loose and leaking. My cousin who brought the problem to my attention has seen it numerous times with Holley carbs. He started wrenching in a speed shop in the late 60s and hasn't stopped yet.

Perhaps I did overstate myself by saying the fitting is all that holds back the fuel in the bowl.

OUS was looking for possibilities, I threw out what info I had.

Here is the better fix:

Edelbrock carb. There, current and many future carb problems fixed.

Later,

Matt

Storm861triple
05-16-2007, 11:46 AM
An Edelbrock will introduce as many issues as it eliminates. I've had many of both, and they both have their issues. At least the problems w/a Holley are fixable. The problems w/an Edelbrock are designed in. I personally wouldn't choose either.

Storm861triple
05-16-2007, 02:12 PM
Here is why the loose booster thoery is flawed. Take a look at these pics:

Boosters attached at TOP of carb body:
http://chevyhiperformance.com/techarticles/p158290_image_large.jpg
http://chevyhiperformance.com/techarticles/p158299_image_large.jpg
http://imagehost.vendio.com/bin/imageserver.x/00000000/scruffy390/IMG_2687.JPG
Booster higher than bowl level adjusting port:
http://www.motortraders.net/~mtn/new/CT-SA083.jpg

So how is fuel going to go UP HILL, and leak out the booster mounting points in a properly funtioning carb?

The reason why fuel is leaking out w/the engine off is because the float bowl system is not doing it's job of regulating the fuel level, in the bowl.

OSUspenc99
05-16-2007, 03:21 PM
Storm, Great post. Exactly what the Holley Tech was trying to explain to me yesterday. Going to go check it out tonight! Let you know

Matt L.
05-18-2007, 06:35 PM
Here is why the loose booster thoery is flawed. Take a look at these pics:

Boosters attached at TOP of carb body:
http://chevyhiperformance.com/techarticles/p158290_image_large.jpg
http://chevyhiperformance.com/techarticles/p158299_image_large.jpg
http://imagehost.vendio.com/bin/imageserver.x/00000000/scruffy390/IMG_2687.JPG
Booster higher than bowl level adjusting port:
http://www.motortraders.net/~mtn/new/CT-SA083.jpg

So how is fuel going to go UP HILL, and leak out the booster mounting points in a properly funtioning carb?

The reason why fuel is leaking out w/the engine off is because the float bowl system is not doing it's job of regulating the fuel level, in the bowl.

YOur right, sort of. While off I don't think the loose venturi clusters will leak. While running they will leak due to the pressure differential drawing fuel through the loose connection.

Also, Who said he has a properly functioning carb? If it were functioning properly I don't think we would be having this conversation.

Later,

Matt

Storm861triple
05-18-2007, 10:44 PM
YOur right, sort of. While off I don't think the loose venturi clusters will leak. While running they will leak due to the pressure differential drawing fuel through the loose connection.

Also, Who said he has a properly functioning carb? If it were functioning properly I don't think we would be having this conversation.

Later,

Matt
Geez-us. IF (and this is a big "if"), his boosters are loose, they won't leak gasoline OUT while the engine is running. They will leak air IN to the booster and the fuel flow that's supposed to be going to the engine. Sort of like a vacuum leak. The pressure in the bore of the booster is LOWER than that outside (and above) the booster, where the booster attaches to the carb body. Please refer back to my posted pics, or look at a Holley carb. This means that if there is a leak at the mounting point, air will be drawn in rather than fuel leaking out.

BUT none of this matters because "fuel leaking out" while the engine is running, (pay attention here) IS NOT THE SYMPTOM THE OP POSTED ABOUT!! Which is why in addition to your posts being inaccurate, misinformation, you're sending the OP looking for issues in the wrong direction.

The OP complained about flooding after sitting shut off. You've talked about:
*At slow speeds it can cause a very low speed stall
*Fuel will puddle on the butterflys
*idle surge issues (??? Even though no fuel comes from the booster when it's idling)

The OP said none of the above. Not only is your hypothesis TECHNICALLY inaccurate, but you're sending the OP chasing issues that don't LIKELY exist for symptoms that he doesn't have! And that is why I posted.

But this is the best part:Who said he has a properly functioning carb? If it were functioning properly I don't think we would be having this conversation.
No sh!t, Sherlock. But whether you're WAG about boosters being loose is right or not, the only possible way fuel could come from the booster when the engine is not running (like the OP stated), is if the float bowl assy isn't functioning correctly (it's too full of gas). Whether he has a loose booster or not, he needs to get his float system operating properly FIRST...then we can see if the has "at slow speeds it can cause a very low speed stall, fuel will puddle on the butterflys, [or] idle surge issues"

The problem here is that you posted a guess about your solution to the problem, and now you won't just admit that you were wrong.

The reason why fuel is leaking out w/the engine off is because the float bowl system is not doing it's job of regulating the fuel level, in the bowl.