Oil pump check valve

[chetbrz]

There is two style pressure plates for the Q,U, and 30u Thin arms and thick arms.  The PA has a 4th style.., cover three arms.  Look at the pictures on pages 80, 81 and 82 of the Master Parts List or post a picture of the pressure plate.  The clutch plate is the same for Q to PB.

Chet...

BTW... "I can crank with the plugs out and with difficulty under compression. "  Sounds normal to me.

[Russ T. Fender]

Thanks Chet.  I can clearly see the difference from the master parts list and I am sure I have the 30-U thick arm pressure plate and the three arm PA version.   What I don't know is if the two are interchangeable.  The more I think about it the more certain I am that they are interchangeable because the PA pressure plate was with the rest of the parts that were stored when I took the car apart but it sure would be nice to have it confirmed before I set everything up and find out otherwise.  My car spent over 40 years on the road as a daily driver so I am sure it had clutch work done on more than one occasion.  My assumption is that at some point the pressure plate was replaced by someone who knew that the PA pressure plate was a viable alternative, at least I hope so!
I guess I will find out soon enough and will post the results.  Wouldn't hurt to have another possible option.

[chetbrz]

I am very interested in what you are doing and if it is possible it would be nice to see both pressure plates.  If you could take a picture I would appreciate it. If you can't post it you could email it to me.

Thanks Chet

[Russ T. Fender]

I will get a picture tomorrow if I can.  One is installed and the other is in my storage space.  For what it's worth,  I just checked some old copies of the Plymouth Four Cylinder Owners Club that I have as I recalled that they did some interchange research in the early '60's. What I found shows that the Borg and Beck 9A1 clutch assembly and pressure plate can be used for PA, PB and 30-U.  I am not sure what that really proves but it certainly suggests that the factory Plymouth pressure plates and clutch discs for the same years should be interchangeable.  At the time the interchange was done you could still get the 9A1 unit over the counter at any auto parts store.  Wish I'd bought a few when I had the chance.

[Russ T. Fender]

Well I think I have solved my problem.  When I went to take a picture of what I have in the car I noticed a faint marking that I had not paid attention to when putting in the clutch and pressure plate.  I scuffed the area and discovered that I have a Borg and Beck 9A1 set up.  I am now confident that I put the right set up in and that this set up is usable for the 30-U, PA and PB Plymouths as the interchange done by the Plymouth Four Cylinder Owners Club indicates.  Chet, I will try to attach a picture of what I have in the car and get a picture of the other set up when I get over to my storage space. I think  you will see that the Borg and Beck unit is almost identical to the Plymouth factory clutch set up.

[chetbrz]

Great thanks.

Very interesting stuff. 

[Russ T. Fender]

Here is the clutch set that is factory issue for the 30-U

[chetbrz]

Thanks, that was what I was expecting to see. 

I wonder if there is a modern replacement for the Borg and Beck 9A1.  I wonder what other cars used this setup in the 60's.

Thanks again.

[Russ T. Fender]

That clutch was used by lots of cars in the early 30' but the last one I can cross reference with is 1934.  Studebaker  Dictator and International C1 and D1. both used it through 1934. When I said you could still get them in the 60's I did not mean any cars of the 60's were using that clutch.  I meant that they were still stocking that part and rebuilding them for cars from the 30's.  I remember when a friend of mine who worked in an auto parts store in the mid 60's called me to warn me that the new parts catalogs they had just gotten in no longer went back to 1930 and that if I needed anything for my car I better get it before they could no longer find the parts references.  Fortunately,  that forced me to get a new radiator, tie rod ends and 2 complete gasket sets as I had been nursing my leaky old radiator and using anti-shimmy springs to compensate for the worn tie rod ends.  Unfortunately,  that "new" radiator and replacement tie rod ends are now older than the ones I replaced but I did just get to use one of the gasket set for the engine rebuild.
I will try to do some research and see if there is a modern substitute for the 9A1 but I doubt it.  It may however be possible to get them rebuilt and there should be a reasonable number of them out there as I know at least a dozen different cars used them.