combustion

[bobc]

After weeks of home & garden renos and some serious birding, I've retuned to the task of getting my 71 westy on the road. Recap: I've got the engine (1600 dp) back together , .003" end play , oil pressure , compression around 100 , valves set at .006" electronic dist,. and new 34  carb. After bench (floor) starting it , I've only been able to get combustion from the 1 & 2 cylinders. I've tried swapping plugs and plug wires checking the firing order , getting strong spark from all 4 plugs, tightening down intake manifold.  I dribbled some fuel into the 3 & 4 cylinders , which got them to fire but then nothing. What should I try next?

Bob

[Volktales]

That is consistent with a vacuum leak to 3 and 4 cylinders. Leaking intake gasket or boot. Or unplugged vacuum line port on 3-4 manifold (if equipped). With a stock carb and manifold, not much else can cause that. Is the port for the brake booster plugged???

[bobc]

the boot and vacuum port are tight and plugged. I torqued down the manifold some more, but still nothing .Tomorrow I'll spray it with some carb cleaner and see what happens .What's your take on gaskets , I've got the paper/fabric ones (does sealants help) on now and I have the metal ones around somewhere. I could switch them out & check the manifold surface.

[Volktales]

Normally I have used the metal ones with Permatex on them. Do make sure your alloy manifolds were actually flat.

[bobc]

So I installed a metal gasket with a film of sealant , checked the surface of the manifold and fired it up - nothing . After removing the manifold again , I noticed that half the raised ridge on the gasket had not been crushed flat. Where the pipe slides into the manifold and is sealed with the boot, it was binding. I cut 1/4" off the pipe which allowed the manifold to set freely on the head . With a new gasket in place , fired it up again and bingo - fire in the hole. Nice sound. Thanks Russ.

[Volktales]

Cool. Glad it worked out.