Holley carb help!

[Robert G.]

I have a Holley R-3811 reproduction carb on a 67 427/390. I did a gasket replacement rebuild and I couldn't get it started(flooding). I then had a shop (very experienced, good reputation) rebuild it. The car seems to start and run fine the first time after a rebuild (2 so far), but once the engine is shut off, it won't start again. There seems to be a massive amount of flooding going on. Does anyone have any unusual ideas for what could cause it to behave like this? I'm sure the shop has checked the usual things.

[Clem Z.]

Re: Holley carb help!

I have a Holley R-3811 reproduction carb on a 67 427/390. I did a gasket replacement rebuild and I couldn't get it started(flooding). I then had a shop (very experienced, good reputation) rebuild it. The car seems to start and run fine the first time after a rebuild (2 so far), but once the engine is shut off, it won't start again. There seems to be a massive amount of flooding going on. Does anyone have any unusual ideas for what could cause it to behave like this? I'm sure the shop has checked the usual things.

checked for warped surfaces where the metering bodies set on the main body. also pressure check the needle and seats with the bowls off of the carb. do you have the correct gasket package between the carb and manifold ?

[Gene M.]

Re: Holley carb help!

Robert,
If the carb starts flooding when turned off the floats are set to high or the seats are NG. Replace seats and reset floats should fix your problem.

Sounds like the rebuild performed was less than what's required. Todays gas seems to give a shorter life to the viton seats.

[Robert G.]

Re: Holley carb help!

Thanks guys,
The guy at the shop went so far as to weigh the floats, so I think he was pretty careful about the rebuild. However, it's back to the shop tomorrow and I'll mention a possible warped metering plate and the float levels. I've had the carb for over 20 years and never ran into this kind of trouble before. After tearing it apart today I noticed there was no pump discharge check ball and don't know whether one is needed, but I will ask him about that too.

[Gene M.]

Re: Holley carb help!

Robert,
The viton seats is all that shuts off the fuel supply. Both primary and secondary ends are the same configuration. No balls here.

[Timothy B.]

Re: Holley carb help!

Robert, There should be a discharge check ball under the squirters, this keeps the accelerator pump from sucking air when filling. These carburetors are very prone to leak if surfaces are not flat.

If the 390 has a cast manifold do you have a stainless plate under the carburetor, should be manifold, gasket then shield and carburetor.

I feel your pain as I went through this with my 3810 but now it seems pretty normal with regard to tuning etc. Check archives because there are many 4160 carburetor posts.

[Robert G.]

Re: Holley carb help!

Gene, the check ball is under what is called the 'primary discharge nozzle' I believe. Unfortunately the diagram appears to be for more than one model so I can't tell if mine is supposed to have one.
Timothy, I may have the gaskets in the wrong order- I think I have the stainless one first followed by the gasket. I'll check that. Thanks.

[Clem Z.]

Re: Holley carb help!

Robert, There should be a discharge check ball under the squirters, this keeps the accelerator pump from sucking air when filling. These carburetors are very prone to leak if surfaces are not flat.

If the 390 has a cast manifold do you have a stainless plate under the carburetor, should be manifold, gasket then shield and carburetor.

I feel your pain as I went through this with my 3810 but now it seems pretty normal with regard to tuning etc. Check archives because there are many 4160 carburetor posts.

the check valve under the pump discharge nozzle is to keep the pump passage full of fuel. if there is no check valve the fuel would empty back into the pump area. acts like putting your finger over the top of a soda straw full of liquid and if you remove your finger the straw will empty out

[Clem Z.]

Re: Holley carb help!

the check valve under the pump discharge nozzle is to keep the pump passage full of fuel. if there is no check valve the fuel would empty back into the pump area. acts like putting your finger over the top of a soda straw full of liquid and if you remove your finger the straw will empty out

some holley carbs have the check valve built into the metering body and have none in the main body passage under the pump discharge nozzle. you can check for this by shaking the metering body and listen for a rattle or just blow backwards thru the pump passage in the metering body and if there is a check valve you will not be able to blow thru

[Gene M.]

Re: Holley carb help!

Robert, The squirter has nothing to do with the fuel inlet at the seats and floats. The problem with the carb is loosing fuel after it is turned off. The float is set way to high and/or the seat (viton) is shot. The fuel today destroys that rubber seat in short order. The squirter has little to nothing to do with the leakage problem he is having.

[Clem Z.]

Re: Holley carb help!

Robert, The squirter has nothing to do with the fuel inlet at the seats and floats. The problem with the carb is loosing fuel after it is turned off. The float is set way to high and/or the seat (viton) is shot. The fuel today destroys that rubber seat in short order. The squirter has little to nothing to do with the leakage problem he is having.

the viton needle tip will stand up to today's fuels but a neoprene rubber will not so make sure you use a genuine holley kit that also use a pump diaphragm,green in color, that will last.

[Steven H.]

Re: Holley carb help!

Robert

Holley's are the easiest carbs in the world to set the floats on; I recommend you give it a go, it can be done with a screwdriver and cresent wrench.

Take those little view screws out on the side of the bowl and see if gas runs out while running or just after shut off; then you will know.

[Gene M.]

Re: Holley carb help!

Clem, Thank you for the clarification on the neoprene rubber vs the Viton. I guess the Viton is the more difficult to find.....?

[Stuart F.]

Re: Holley carb help!

Are you sure there is nothing hanging up the float(s)? I have seen it happen a lot, specially with today's gas, where the fuel hose to the carb is not replaced when the carb is rebuilt. These hoses are the item that gets attacked by today's gas and taking them on and off a few times tears away chunks and bits from the hose inside which then hangs up in the needle/seat.

Just a thought.

Stu Fox

[Clem Z.]

Re: Holley carb help!

Clem, Thank you for the clarification on the neoprene rubber vs the Viton. I guess the Viton is the more difficult to find.....?

if the tips on the needles are gray or red they are viton