VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 33 coupe belching soot

1934 was first to have water jets in the head.
First with the BLUE FLAME cylinder head.

Yes, Jets, 34....I think his overheating is still due to rust chunks hanging up on the head gasket preventing correct water flow.

Well the overheating is now the least of my worries. I ran the car and tried to go over 35 mpg-no power. On my way back home the car boiled over. When I got home, I allowed the engine to cool a bit and I retested the compression with the engine at normal operating temp (as opposed to cold when I got consistent readings of 70 in all cylinders). At operating temperature (after the engine boiled over and cooled) my readings were:
1. 60
2. 59
3. 59
4. 60
5. 60
6. 60

I then shot oil in each cylinder and retested
1. 80
2. 80
3. 70
4. 70
5. 80
6. 85

Next morning I tested again
1. 68
2. 65
3. 68
4. 65
5. 79
6. 79

Can I now assume the rings are bad and I need an engine rebuild? If I need an engine rebuild, the closest major cities likely to have a good engine shop that might even consider this rebuild are Charleston (2 hours) and Savannah (1 hour). I will check the VCCA resources, but any suggestions are appreciated.

Thanks

Your engine might only require a valve grind and ring job with a good inspection of the head for cracks. I don't think you need a shop in a major town as your engine is similar to many straight sixes local shops have done. I have work done in my small town with excellent results. It is not how big the shop, it is all about what the workers know. You may have to be their parts runner but what of it. There was a big rebuilder in LA Calif. that hired my friend that had only average mechanical aptitude. He told me some strange stuff they did.

Trying to follow along here with your descriptions;

If the car won't go over 35 mph on flat ground, and you have at least 70psi compression, you need to find the real problem, as it is not compression related (if 35 mph is true!)

A person who worked on cars for 50 years would be looking at many things; Like ignition timing not advancing at all, obstructions in intake or exhaust passages, main jetting problem, etc.

I'm not saying that you won't need to pull the head at some point, as one strange thing I found on a 80 chevy C10 inline 6 cyl that had that very strange smog exhaust recirculation system; the intake valves had so much black carbon build up on the stem side, that the valve looked like a pointed Ice Cream cone! The valves still opened, but the air could not flow fast enough, to go over 40mph on the interstate, floored.

I certainly would not condemn the entire motor quite yet, until I found out why it can't go faster than 35. Heck, I suppose the brakes could be tight? it's near impossible to diagnose every single possibility over the internet. :)

I agree with frank32....There is another problem.

Sounds to me like you are starving for gas beyound 35 mph.
I would look at the screen in the top of the glass bowl fuel pump to see if it is clogged up with fine grit. Check to be sure cork gasket is good and glass is tight against it when put back. Look at the screen in the carb on the high speed jet. Low speed jet is good to about 30 mph.... See the underside of the carb. Upside down. There are covers with straight slots for screw drivers. Behind these are screens. Could be some fine grit got in there and blocked your high speed jet. Look at your float level in the "well" on carb to be sure you are not to low on the float and running out of gas while driving. Check the Accelerator Pump Plunger Arm to be sure you are in the middle hole. Make sure the throttle lever adjusting screw is not stoping the pedal from making it all the way to the toe board inside the car. All this providing timing is still dead on. Pull out choke at 35 to see if it goes faster. If so then your air mix is wrong. Carb needs checked then.

I haven't been following too closely but is it possible the valve springs are weak? Could someone have replaced them in the past? This would cause the valves to float at higher speeds.