The Stovebolt Site Forums The Shop Area Engine Shop 41 dump 216. No sack.

My 216 in the 41 dump seems to run pretty well. I went out last night after not starting it for a few days, pumped the throttle 4 or 5 times, choke and fired right up.
I took one of my sons for a ride down a dirt road for about a mile. I could barely hold a speed to keep it in fourth with the low rear end gear. Slip it into high and she starts slowing down with your foot to the boards.

So far I have confirmed or changed the following:
-Set timing. Pointer points to the BB at low idle & #1 cyl.
-Advance is functioning. Verified with timing light.
-New carb.
-New points & gapped.
-Tank cleaned out well. New 3/8" steel fuel lines & filter.


What I haven't done and probably should:
-Change plugs & wires.
-Jetting?
-Ck compression
-Leak down test.


The motor is a 1937 216 bored .060" at rebuild in 1954.
Anything else you can think of that I should check while I'm waiting to build my new motor?

Try creating an exhaust leak- - - - -loosen the down pipe at the manifold, or remove the muffler, or drill a hole in the pipe ahead of the muffler, etc. One thing most people don't look for is a clogged exhaust system. I've found mufflers packed solid with rodent nests, collapsed double-wall pipes, and on newer vehicles, catalytic converters clogged solid with carbonized oil from a worn out engine that consumes a lot of oil. A sure sign of a clogged exhaust is intake manifold vacuum that drops to virtually nothing as soon as any load is put on the engine.
Jerry

Excellent idea. I've seen the same thing before. Fire an engine up and blow huge mice nests out the tailpipe if you're lucky.
I'll give it a shot. Thanks.

MY 235 runs LOUSY pointed right at the BB. Especially under any kind of load.

It responds very well to advancing the timing a bit more than that. It would be super easy for you to experiment with more timing. Just don’t get carried away if you hear pinging.

Jerry’s exhaust obstruction idea is a good one, too.

I'll give that a shot too. Can't hurt and easy enough. Thanks.

... to go along with what JW51 said, the mechanical advance starts kicking in at about 400 RPM in these distributors, so make sure the engine is idling at or below that speed before trying to set timing to the BB. I like to set mine on the BB with a timing light and then use the "RA" adjustment to advance the timing a little bit to find the sweet spot. The advantage in doing it that way is you can always get the adjustment back to stock without a timing light.

Bill, for clarity please explain the “RA” adjustment.

I'm going to assume he meant retard/advance adjustment.
I keep forgetting the idle is so low in our engines. I'm more used to big block Chevys. I suspect I might have set the timing at 600-700 rpms. I'll throw a timing light on it again the next time I'm looking at it and make sure I have the idle low enough.

Sorry. I couldn't remember the proper name and was too lazy to look it up.

Picture is from a 1951 GMC Maintenance Manual, but Chevy works the same way.

Text from the same book says 'Set manual advance halfway between "R" and "A" '

It then goes on to explain how to set timing using either the "engine not running" or "engine running" method.

Once that is done, you can "tweak" the timing for best performance by just adjusting the "manual advance" without the need of a timing light and can set it back to factory specs by adjusting "manual advance" back to mid-point.

My 228 GMC seems to like about 4 degrees towards the A.

The “octane adjuster” thing?

My two cents - for the kind of thing the OP is doing here….

Just set the idle down as low as it will go without dying. See if a little more advance (loosen clamp and twist dizzy) makes it pick up and run smoother. Find the sweet spot and then try a restart. If it struggles to start you might need to back it off a bit.

Worrying about a specific RPM or a numerical timing value can come later. My thought is just testing the timing theory.