Buick35

hard starting after sitting a week

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Hi,My old Buick starts on the first push of the starter after its been run the previous day but if I let it sit more than a week I either have to pour has in the carb. or pump the crap out of it . Other than installing an electric fuel pump is there anything else that I could do? Is something wrong with my carburetor? It's a 35 Buick with a Stromberg carb.Thanks,Greg.

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4 minutes ago, Buick35 said:

pump the crap out of it

That does not do anything if the float bowl is dry.  All you need to do is let it turn over enough to suck the fuel from the tank.  Or you could just drive it every day.

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Nothing's wrong. Today's gas evaporates at room temperature so after a week or so, the bowl is empty, or nearly so. It takes some cranking for the mechanical pump to pull gas up from the back of the car and refill the bowl, which is why it takes so long to start. An electric fuel pump neatly solves this problem and I don't consider it a crutch. All my personal cars have them and I use them to prime the carbs so the car starts quickly. Saves wear and tear on the starter as well as spinning the engine without any oil pressure. An electric pump can also help on very warm days if you experience problems with the gas pre-vaporizing before it hits the venturis.

 

So nothing's wrong, but given that today's gas is much different than 1935 gas, adding an electric pump is the quickest, easiest solution that also has other benefits.

 

Hope this helps!

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1 hour ago, Buick35 said:

 pump the crap out of it . 

 

This actually makes the issue worse!

 

You are pumping fuel from the bowl as the fuel pump is trying to fill the bowl, but not enough to cause the engine to start.

 

Jon.

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I have a couple of cars that do this.

I keep a squirt can handy.

It only takes a few seconds to prime a carburetor manually.

 

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Everyone has their own method.

 

I use an empty mustard squeeze bottle that I fill with fresh fuel, and fill the carburetor bowl through the bowl vent.

 

Or, in the case of various lawn & garden tractors, tillers, weed eaters, etc., that have sat all winter; a small psssst of starting fluid.

 

Jon.

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remove the carb, turn it upside down and look for a small  plug that is usually driven into bottom of fuel bowl for acess. mix a little dab of epoxy and cover it up. this was a common problem on rockchester carbs. might solve yours.

 

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Posted (edited)
9 hours ago, cheezestaak2000 said:

remove the carb, turn it upside down and look for a small  plug that is usually driven into bottom of fuel bowl for acess. mix a little dab of epoxy and cover it up. this was a common problem on rockchester carbs. might solve yours.

 

 

This allegedly "common" problem on Qjet carbs is usually NOT the problem. It's very easy to test for leaking well plugs. Simply prop the carb up on your workbench with blocks. Put a piece of paper under it. Fill the fuel bowl and let it sit overnight. If there is no stain or wetness on the paper, there is no leak. Unfortunately, ever since Doug Roe wrote about this in his Rochester book, people have incorrectly blamed the well plugs for all sorts of problems. Only the 66-67 Qjets with the stamped cup plugs have this issue. Qjets since 1968 have spun-in aluminum plugs that do not leak. I've rebuilt far too many Qjets that have the suggested epoxy coating on the plugs, and after a year or so, the epoxy has lifted and is certainly not sealing anything.

 

As others have noted, the real problem is that fuel evaporates when the car is not driven regularly. Couple this with a weak fuel pump and you get hard starting problems after sitting. Ethanol can accelerate the deterioration of the check valves in the pump. Once that happens, it can take a LOT of cranking of the engine to refill the carb fuel bowl. I recently replaced the pump on my 62 Olds and it made a world of difference.

Edited by joe_padavano (see edit history)
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Posted (edited)

When the Rochester Q-Jet came out in 1965, it had several "teething" problems:

 

(A) internal dashpot (fixed in 1966) (can be fixed by professional rebuilder, if he/she wishes)

(B) "umbrella" fuel valve (mostly fixed in 1967) (can be fixed with an available kit)

(C) press-in well plugs (fixed in 1968 as mentioned by Joe above)' (can be fixed by professional rebuilder, if he/she wishes)

(d) (small d) float pin placement (novice rebuilders could break the casting plus not ideal for high performance work) (fixed mostly by 1971)

 

And an on-going issue, like virtually all "modern" carburetors, an aluminum throttle body that normally requires primary bushings to be installed after some 50k~80k miles.

 

Overall, a wonderful street carburetor that can also easily be adapted to straight-line racing. 

 

Jon.

Edited by carbking (see edit history)

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I don't think the owner of a 1935 Buick has to worry about the quirks of a Rochester Quadra-Jet...

 

Were the '35 Buicks still updraft Marvels?

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3 hours ago, Matt Harwood said:

I don't think the owner of a 1935 Buick has to worry about the quirks of a Rochester Quadra-Jet...

 

No, but the issue of leaking well plugs was suggested as a cause for this problem. The advice remains applicable. If you REALLY think that's the problem, it is trivially easy to test before doing anything.

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