Weber Hot Start ?

[9146FAN]

stock 2.0 T, with 40 mm webers with correct jets, venturies etc. Starts right up when cold, but needs alot of cranking when hot, almost like it's flooded. Anybody know about "perculation"? Are there any fix's for it? Thanks, Eddie

[EarlyPorsche]

I dont know if this helps but I have the same engine and carburators and I just hold my foot the pedal just a bit and crank her.

[Steve@Rennsport]

Eddie:

Any and all carbureted installations MUST,......MUST use insulator plates between the heads and manifolds to prevent heat soak and the resultant percolation that floods the engine. Its a major step in reducing the liklihood of engine fires.

[9146FAN]

Steve- You got my attention with the FIRE scenario. I'll look at the bottom of the manifolds, but I don't think I have spacers. Thanks for the advice.
Prost, Eddie

[shbop]

Originally posted by Steve@Rennsport
Eddie:

Any and all carbureted installations MUST,......MUST use insulator plates between the heads and manifolds to prevent heat soak and the resultant percolation that floods the engine. Its a major step in reducing the liklihood of engine fires.

+1 on what Steve said:
Had the same problem. Installed the insulator plates--bingo!
Hardest part was r & r'ing the intake studs. If you don't have one, buy a stud removal tool. No heat, no sweat, no problems.

[911pcars]

PMO has a float bowl vent fix kit. A drilled hole vents the float bowl to atmosphere to prevent heated fuel from expanding into the throttle bore and causing flooding.

Your float level might also be a tad high. Use the PMO float gauge to confirm.

Sherwood

[Grady Clay]

Here is a good thread:
”Early 911 Warm Start Problem“

Best,
Grady

[ValveFloat]

One thing that I did that helped with the hot start problem is to move the pump from the engine compartment to the front of the car.

So if your pump is in the engine compartment, you might consider moving it.