Finally got my Skylark 69 350/4bbl to fire after a top end rebuild. Replaced all valves, springs, seals, water pump, oil pump, etc. with an awesome rebuilt carb from a local expert (Qjet), and stock SBB 4bbl intake. I ran it for 5 mins with what I thought was correct timing before I noticed the intake runners at 5/7 and 4/6 cooking the new paint super hot to burning/black. See pics. I went to shut it down and it ran-on without coil spark and burped hard out the carb before dying. Before I do something stupid (if I haven’t already) please advice on what to do next? I want to fire it up again and get timing correct but don’t want to destroy it before even driving. Thanks Chris in PA
That is the cross over passage area to warm the carb pad in cold weather. cant see it in the pictures but do you have heat riser installed and is it fully open? What was the coolant temp when you suspected it was getting hot?
Thanks Briz, I do not have the riser installed as I could fit the new dual exhaust without it being an issue. I will try again and adjust the timing right after startup and see how it reacts. I have a dwell meter and will try that after if it smooths out. I might be over cautious but have been putting this together for 3 yrs now and don’t want to screw it up. Thanks
You did not Answer Briz's question about the coolant temp. It's a good idea to have a quality temperature gauge so you actually know how hot the engine is running. If you are hoping to avoid pain and work in the future, set this up first. The browning out of the heat riser passage isn't that unusual depending on the paint that was used for the intake...
When using stock 69 distributor, timing is zero and vacuum advance is manifold. Make sure that’s correct and choke is pulling off. But for paint to burn off there at crossover is normal. Paint was probably not high temp either. Set timing to 4 if using the stock 69 distributor.
If you idle any engine with retarded timing, it will heat up. I second connecting the vacuum advance to manifold vacuum so that timing is at least 14-20* at idle. Verify that with a timing light, don't ASS-U-ME the canister is good.
Ok guys thanks for all the input. I’m a Chevy guy and this is my first Buick. I discovered a really simple bonehead issue. The throttle pot is WAY out of adjustment and very firm. This was kicking the throttle up high to about 2k rpm at rest which I took as a timing issue. Took it off and set everything to normal rpm and suggested timing. Motor runs nicely and I found zero leaks. Tucked my tail though when my wife stormed out to the garage for waking her up late !Might need to tighten up an exhaust manifold bolt or two but problem solved. Thanks again! First movement under its own power since 1983 soon.
