TheSamba.com :: View topic - Hard to Re-start after driving

Mon Sep 22, 2008 12:08 pm

I picked up a new to me 68 stocker. The only information I have is that the engine is a "new" replaced in 2004 by Herr Schmidt's in Houston 1600 DP, H30/31PICT, generator. Looks all stock to me so far...so far. My problem is that when I start it in the morning, I tap the gas and she fires right up, sputters a little for a short time, I figure that is warm up time. I drive it say 10 minutes or more and stop somewhere. Then when I try to start it again, it turns over good but no fire. A friend said it smelled rich so I adjusted the carb a little as per instructions I found (small and large screws on side of carb). I'm just stumped on why it is so hard to restart after travel and I want to get it a little more reliable as it is my daily driver right now and would like to take it on longer trips (3hrs or more). I have not messed with the valves yet BTW. I figured they might be "close" to right. Thanks for all the help anyone can give me.

Mon Sep 22, 2008 12:24 pm

ok, this is a very very very very common problem. vw engine bays get very hot causing the fuel in the lines to vaporize and not reach the carb after you shut it off. there are a few things you can do.

1. when this happens put a piece of ice on the fuel pump to cool it down and it will fire right up. now your like, WTF??? everytime??? well option 2 is better

2. get you a tennis ball (not your dogs favorite). cut an X into it and slide it over the locking mechanizism of the deck lid. this will prop the lid open just enough to let some heat out and should solve the problem.

also check and make sure your fuel lines are not running near anything or touching anything to keep them hot.

also off topic if the fuel filter is in the engine bay, GET IT THE HELL OUT OF THERE!!!! move it under the car, you don't want a fire in your new toy....

Mon Sep 22, 2008 3:00 pm

If you route the fuel line further away from the intake manifold, it wont get as hot and solve the problem as well.

Mon Sep 22, 2008 3:07 pm

Also try retarding your timing a liitle,this will supply spark a little sooner,and also richen your fuel mixture.

Advanced and Lean=HOTTER
Rtearde and RICH=WAY COOLER

Mon Sep 22, 2008 4:11 pm

I solved my hot restart problem some time back.

It was due to excessive pressure from the fuel pump. If your idle mixtures are right when running, no amount of adjustment will help.

What happens is the excessive pressure will force it's way through the needle valve on the top of the carb, causing it to overflow and vent through the brass tube and drip down the throat of the carb (at least for mine it did).

Attaching a fuel pressure gauge and shimming it down to slightly under 3 PSI fixed my problem.

Mon Sep 22, 2008 9:05 pm

If you are running rich, and foul out a set of plugs, just setting the right mixture will not always fix it, I say: Replace those spark plugs!

Mon Sep 22, 2008 11:08 pm

Check your carb, if it smells rich it may be your needle valve sticking open which will allow gas to keep pouring in even after your car is shut off. Just pull off the air filter after you turn it off and see if there is fuel still dripping into the carb, if so thats a good chance it may be your problem

Tue Sep 23, 2008 6:28 am

li_gangyi wrote: I solved my hot restart problem some time back.

It was due to excessive pressure from the fuel pump. If your idle mixtures are right when running, no amount of adjustment will help.

What happens is the excessive pressure will force it's way through the needle valve on the top of the carb, causing it to overflow and vent through the brass tube and drip down the throat of the carb (at least for mine it did).

Attaching a fuel pressure gauge and shimming it down to slightly under 3 PSI fixed my problem.

That's the first thing I would check... I run across this a lot... and check the valve adjustment too if you have not already... no telling when the last time they were adjusted.