VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc 1932 chevy/backfire

I have a 1932 chevy with a 194 engine. I had to replace the exhaust manifold gaskets along with rebuilding the carb. I had some issues with the fuel pump leaking . I did get it to stop. This car has been setting since 1968 in a shop. I cleaned up the points and have it set at 18 thousand. It has good spark. I attempted to start it several times as it backfires back through the exhaust. . Is there anything i need to do with the advance to the distributor while starting it? Over the years of storage, the cylinders had marvel mystery oil in it. I did put some oil in the cylinders and left the plugs out while i turned the motor over. I wanted to lube up the inside.

I was reading in the forum that the spark plugs should be set at 40 instead of 25. 40 thousand seems like a lot.

With the timing advanced to 18 degrees the AC-C87 spark plug gap has to be set to .040".

Thanks. I just need to get it running for now. When I try to start the car, do i pull out the cable on the dash to get it started. It is just back firing now. I take it that it has to be AC plugs. I have a set of new champion plugs. Will those work?

The first thing I do is run a compression test. That will tell you a lot. If it is ok Then look at the firing order and timing.

Pull out the "spark" cable on the instrument panel each time that you start the car. That retards the spark making the car easier to start.

Yes, you must use AC-C86 or AC-C87 plugs for the .040" gap and the 18 degrees timing.

I've never used the spark retard cable. A early 30's Chevy engine in good shape starts easy.

Start with the basics.
Make sure that the advance mechanism in the distributor is free and that the distributor itself is in good shape - no loose bearings.
Line the timing mark up with the pointer and turn the distributor so that it points at #1.
Make sure that the plug wires are in the correct order (153624, I think)
Timing does not need to be at 18 degrees to run well. That said, the experience on this board is that optimum performance on modern fuel is .040 gap and 18 degrees static advance.
Make sure that the carb is clean and adjusted properly.

It sounds like you are close. If it's backfiring, that means it's firing and getting fuel.

Thanks. That helps. I keep reading about the timing mark, I have the book for the 32 confederate (repair) just can not locate where the timing hole or location is. Is it on the driver side upper side of the bell housing? I thought for a moment and wondered if it was around the lower end where the dust cover is. I did go over last night and done the compressing coming up on #1 and got the pointer set to the number 1. Everything looks good. Now comes the compression on all cylinders. I had #1 70 #2 25 #3 60 #4 0 #5 30 # 6 60 Pulled valve cover off. I had two valves stuck. Sprayed it with rust buster, took off rocker arm and tapped it a little and let it set. I kept doing that for several times and the valves are not stuck. I did get the compression on #4 from 0 to 30. I poured some oil on the top end and around the holes to the lifters. Valves are working now but when I attempted to start it, it did back fire. No start. I am thinking the lifters needs pumped up. I am in hopes to get it up and running. Setting in a shop since 1968 did not do it any good.

The timing hole is on the driver's side of the bell housing. It is a square hole with a pointer.

Make sure the spark plugs order is correct as well as timing. With a large difference in cylinder compression popping is expected. It probably will be necessary to have the rings scrap off some rust or corrosion to get the cylinders cleaned and rings reseated. It probably will be necessary to squirt some carburetor cleaner in the carburetor throat to get it to fire and run as it burns better than gasoline. A few small squirts should keep it running. Be sure to keep the aerosol can far enough from the carb so it does not get lit up! With fuel, enough compression and correct timing it should run on its own.

Did all the compressions come to at least 60 after you freed the valves????? If not it will be hard to start.
Considering it has been sitting that long I would guess the valve faces and seats have rusted and now wont seal properly, there is also the possibility of rusted cylinder bores which will not help the compressions.
Tony

Thanks. Found it. I turned it over several times and could not find any markings on the flywheel. I will have to some how hold a stone chalk in the hole and turn it and maybe it will show up.

When I set timing to get the engine running for the first time, I used a crank handle to find the timing marks (bumping the engine with the starter never got the marks in the window). One I found them I used a white pencil (chalk, white out, white paint all work) to highlight them. Next I used the crank to get the engine to TDC - 6 degrees or so, #1 compression. After priming the carb, it fired right up.

If you use a 12V timing light connected to an external battery like from a riding mower, make sure that the negative terminal from the external battery is connected to a good ground on the car otherwise you will fry the timing light. I found out the hard way.

If you still have a dead cylinder, it should still start, but run like crap.

Thanks. The compression from #1 70 #2 25 #3 60 # 4 30 #5 30 #6 64. My brother put marvel mystery oil in the cylinders over the years while setting. Maybe I will have to pull the head off and have the head looked at. I was in hopes to get it to run for a short time. I had to stop trying to start it as the recent rebuild on the carb started to leak out of the top bowl. The guy that re-built the carb told me that he had to add an extra gasket because the top was so warped. Of course he had to go back and do some other re-adjusting. I had to stop in fear of having a fire under the hood. Not sure if i can salvage the carb now. Maybe there is some other gasket material out there that i could use to make a better fit. I thought that maybe if i get the leak fixed, i could try to pull start it.

A second (or thicker) gasket simply makes the casting warp worse. The solution is to CAREFULLY straighten the casting, using heat and pressure.

Jon.

Thanks. I was wondering about the timing light set up. I took all the plugs out and got what i thought was the #1 cycliiner close to compression and found the lobe coming up on the distributor and then looked at the flywheel. I could not see anything of markings. I then took and moved the motor by hand with the fan blades. I still did not find the marks. I went through several times and could not find it. Maybe it is there but for some reason with a good light, never did find it. I noticed that you mentioned taking it to six degrees. Is that where you then set the distributor?

Thanks. I see what your saying on heating up the carb and working it back. Is that pot metal? I would have to have some one else do that for me so I know that i did not destroy it. Im curious to where to add the heat at. Could you take a flat piece of metal and lay it on there and mark out the holes, drill and tap the holes , mount the piece on the metal, heat it up and start drawing down the screws?

I set it at around 6 degrees BTDC to get it started. It's set at 18 now that it's running and driving well. But I'll add that it will start even if timing is retarded after TDC by some amount. It won't run worth a crap, but it will run.

I guess the point is that it will start as long as the timing is in the neighborhood of 6 degrees BTDC (probably + 12 degrees)

Easy to do when the carb is disassembled; or if you have a junk lower (cast iron casting).

(A) assemble the BARE bowl cover to the BARE cast iron throttle body with no gasket.
(B) snug the screws, but do not tighten
(C) with a feeler gauge, measure the warpage in the center of the side of the bowl cover you can see. If less the 0.003 (three thousandths) of and inch, nothing needed
(D) assemble a large C-clamp in the center of the bowl cover, and snug until the warpage is reduced by 0.003 (three thousandths of an inch) DON'T TRY FOR MORE!!!!!
(E) insert the assembly (bowl, bowl cover, and C-clamp) in an electric oven; if you don't have an electric over, buy one! (this step important)!
(F) heat to about 300 degrees F.
(G) after about 15 minutes, turn off the over, and walk away
(H) about an hour later, remove the assembly (the C-clamp will have fallen off) from the oven.
(I) repeat steps C ~ H

DO NOT QUENCH, DO NOT TRY FOR MORE THAN 0.003 AT A TIME, DO NOT TAKE SHORT CUTS!

I have been using this method for 40 years; it works.

Do NOT use the oven your significant other uses to bake brownies

And just for the record, if the bowl cover is warped, it probably also needs the intermediate shaft bushed.

Jon.

Thanks, The step by step seems like it will work. I will give it a try.