37 engine problems

[Deleted User]

Hello Everyone,

I have a 37 coupe that I have had a problem with for a couple of years I have tried everything I know to solve it. The car has been sitting for the last two years due to frustration but I am ready to try once again.The problem is when the car is cold it runs fine. Once it has warmed up it is Ok if you give very light throttle pressure but the minute you give it much gas it is like you turned the key off. Below is all the things I have tried.

I tie wrapped a coil to the fire wall and hot wired it directly to the battery to eliminate the coil, ignition switch, wiring etc. I removed the gas tank, cleaned it out, flushed all the lines, put an electric fuel pump through the stock pump then around the pump. Walt suggested that the muffler may have colapsed inside so I cut it of in front of the muffler. New points cap, wires rotor and several condensers. Removed the distributor checked to see if it was gounded also put in the oven to see if it was breaking down when up to temperature. The carburator was rebuilt about 10 years ago but not since I have been having the problem. I took it apart and has no visable debris in it. I think it fuel related. Any ideas would be greatly appreciated.

Ron

[Deleted User]

It almost sounds like a rubber hose collapsing as soon as it gets warm but that shouldn't be an immediate reaction. It does sound though like it's starving for fuel and when you try to give it too much the engine dies. We had a car once that would do that because of a flap of rubber inside a fuel line that would obstruct the flow if it flipped down. I would replace all the rubber lines first if there are any.



Harry

[Deleted User]

Last summer I had a similar problem. Found that there was a piece of "crud" (for lack of a better term) stuck in the pick-up tube inside the gas tank. It would start and idle. Sometimes it would even move for awhile. However if I tried to drive it the car would always die.

After determining that none of the rubber hoses were colapsing I pulled the pick-up out of the tank. (tank was clean by the way).

I blew in one end with compressed air and made a mark on the wall with a nasty little piece of crud.

It has run fine since.

Good luck!

Park_W

Ron, are you speaking literally when you say it quits just like you turned the ignition off? Stops instantly with a heavy accelerator setting? No surges, faltering, etc. ? If that's the case, it sounds more like ignition than fuel. You can rule out "fuel supply to the carburetor" problems with a temporary jury-rigged gravity feed source positioned above the carburetor. One other remote possibility in the fuel category ... be sure the carb float drop is set correctly, and that neither the float or the needle valve is hanging up on anything. That can restrict flow into the carb. Now for ignition: Does the car have an original type engine in it, with only mechanical spark advance? When you pull the center wire out of the distributor and hold it near (1/4") from the block to check the spark, is the spark pretty healthy, or pretty anemic looking?

junkcarfann

This could also be an accelerator pump problem...either the pump is not getting fuel, due to a plugged inner passage in the carburetor, or it is not squirting the fuel that it does have.



You can check the pump by removing the aircleaner with the engine off, and manually operating the gas pedal linkage from idle to full throttle. Make sure the choke is open.



As you "floor" the gas, look down the carburetor throat with a flashlight, and you should see a steady solid stream of fuel squirting downwards inside the throat of the carburater.



Anything less than a full stream, i.e. a dribble, or nothing, means that when you step on the gas the fuel-air ratio goes way lean, starving and thus stalling the engine. When cold, the richening effect of the choke masks this, and the engine appears to function normally.



If you do not see a good squirt of fuel, check to see if the accelerator pump rod is hooked to its linkage. It is a rod sticking up thru the top of the carb. You will have to remove the "hat" that is on top of the carb, that covers this part of the carb, (it usually says "oil under screw"). Also, this linkage rod usually has 3 holes it can fit into...make sure it is in the hole that provides the greatest movement.

Hope this helps.



ps...just because the carburetor was rebuilt does not mean this is not the problem...the accelerator pump piston is leather, and can dry up or crack, etc.

[Deleted User]

I will look at my notes but I believe I replaced all the hoses to be sure on was not collapsing. Also when I disconnect the hose going to the carburator with the electric pump on I get a good flow of gas into a can.



Thanks for the help



Ron

[Deleted User]

I'll have to get into the carburator once again. As far as the spark goes I assume you are talking about the wire coming from the coil. I tie-wired a good coil to the fire wall and hot wired it directly to the battery as the stock coil, ignition switch and wiring are all on unit so it should have bypassed everything. It is a stock igntion system.



Thanks for you input

Does anyone have a carburator they want to sell for this car? I am not at home now but I believe it is WD 1

[Deleted User]

rmcf - This is probably not your problem , but I'll till you of a simular problem I ran into. The car ( stepdown , hydromatic ) was towed to my house. It would start and idle but as soon as I put it in gear, ( to get it into my driveway) , and give it some gas it would die. I finely found the problem. Someone had left the little spring under the metering rod piston out, causing the metering rod to stay down, starving the engine when puting it under load. Norm

jtroberg

Looking at the problem from another angle - I once had a similar problem that started just after I removed the distributor for some reason. When I replaced it, I was accidently off by one gear tooth (speaking of the gear at the bottom of the distributor shaft) from the correct setting. It would start, but as soon as I gave it any gas it would quit because the timing would advance, and be too far off for the engine to keep running.

If nothing else works, double check the distributor setting. Good luck!

John

[Deleted User]

Thanks John,



I can recheck the timing with a light. I believe I did check it but like I said I got so frustrated I haven't touched the car for 2 years. I figured I would get input from everyone before I got back into it. Thanks for everyone input.



Ron

terraplane8

Check to make sure the linkage beside/under the floatbowl for the accelerator pump hasn't come off the spindle connection. That's what happened to mine, would run fine on the idle circuit but died when you pressed the accelerator. top speed was around 25mph.