Need some advice.

[pat in Santa Cruz]

properly set in the motor mounts, the engine slopes to the back 3 degrees. This slope encourages the oil to run back. There is so much flow in there that it runs over the dams and over into the cam gears as well. The oil also runs around the dams through passages created by the cover. Look at the cover and observe the gasket surface. The dams are only gasketed partially up from the bottom of the cover. A passage way is created between the dams and the cover for the oil to run back.

BTW, ta loud clacking sound is also typical of a sticking piston. Its a loud sound, similar to a rod knock or a very loose tappet, but its usually louder than a tappet. The usual culprits are 3# and #4 pistons, which stick on the cylinder walls between the two. If this is the case, you will see piston deposits and /or scoring on the cylinder walls. Its most common on a new engine that's getting hot, but it can happen to one that's normal operating temp too if the coolant flow to the back is poor or obstructed or of the engine is being loaded too heavy prior to breaking it in. ( e.g. driving too fast).

 

[CWPASADENA]

Thanks for the responses guys, I'm going to need a lot of encouragement here, as I'm getting pretty frustrated. I put everything back together today, (before your posts). I soaked the guides real well and oiled them up before putting it back together. When I ran it I had the rpm's up and goosed it occasionally. Part of the time it ran great, part of the time horrible. Loud clacking noises that bring a chill at times. When it ran well, I could accelerate it well. When it ran bad, the throttle did nothing. Should I tear into it and start over? Should I run it to beat the band? I'm lost

I think from reading all your posts, you have a few sticking valves. It may only be one. If an intake sticks, there will be a clacking sound and the thing will run like crap. A sticking exhaust valve will make noise but usually will act like just one dead cylinder. The more you run it, the better it MAY get but if you have a valve guide that is slightly gaulded, it may never resolve itself until you pull the valves and fix it.

I DO NOT think it is a bad bearing as that usually will only make noise and the engine will not necessarily not run bad. Same for a bad piston or pin.

How about checking manifold vacuum? If the vacuum is good when the enging is running good and goes to hell when it starts to make noise and runs bad, you can almost be assured it is a sticking valve.

Your restoration really looks good. Do not get discouraged and do the best you can to diagnose the problem before you tear into it.

Just my opinion, (from more then fifty years working on this old stuff)

Chris

 

[Dave in MN]

Hi Russ,
I do a bit of Model A engine rebuilding.
The engine sits at a 3 degree tip to the rear. The, running engine, oil level in the rear well of the valve chamber will not exceed the lowest height of the oil return pipe opening. The front and middle chamber areas are regulated by the heights of the baffles to the rear of each area. Upon shutting the engine down, the oil level in the valve chamber may continue to drop as oil is seeping down through the main bearing oil tubes and also seeping down to the cam bearing surfaces from the feed holes. This is why an engine with a worn rear main bearing will often continue to leak after it is stopped. A portion of the rear chamber oil may end up on the floor.
Hope this helps.
Good day!

Dave in MN
www.durableperformance.net