83 Chris Craft engine question

[Jeffgrant00]

Update >
So i talked to the fella I bought the boat from again and he swears up and down that the standard rotation 305 is what was in the boat. 305k
He said the transmission is a 1.1 gear ratio and that even if it was supposed to be a reverse rotation engine that it wouldnt matter????? Now im allllllll confused. He said he had to get a ring gear machined amd pressed on so it would fit on the right side of the engine? Is he right, 1/2 right or all wrong?
He also said he has a double roller timing set put in it with a chain because it was heavier duty amd the the original engine was gear to gear. He as well told me.that he set it up for HEI ignition.
HELP!!?

 

[alldodge]

swears up and down that the standard rotation 305 is what was in the boat.

You might be in great shape. The direct drive tranny can be run in either direction, the issue is with some older models were not set up to do so with full power, new ones of today are. If the tranny is setup to do this then your golden, and it sounds like the PO has done this. So the tranny is shifted in Rev to go Fwd so to speak.

As for the timing chain set I wouldn't bother with it, don't see it adding any benefit

 

[CrazyFinn]

I might be wrong but...

Back when I was researching buying the exact same type of boat (and reading through the Chris Craft Catalina message boards and other sources), this is what I discovered. The 251 Catalinas were built with a reverse rotation engine, Paragon transmission/straight inboard drive train. Those Paragon transmissions, from what I could find, will turn either way, but you have to make sure the oil pump in the transmission is set up for the way you want to turn it (apparently it can be changed). IF that is the case, all you would need is a new propeller that is standard rotation (after changing the oil pump setup in the transmission). Forward gear will still be forward gear, just spinning the other way. You DON"T want to use reverse for going forward on these transmissions from what I understand.

The other thing I discovered is that some people had issues with when swapping engines was getting them to fit - seems that some of the Chris Craft engines used shorter pans, intakes, etc so that the engine wasn't as tall. If that is the case, and your engine is too tall, you might have to be creative in raising your floor a bit - or something. Or it might not be an issue at all.

 

[Jeffgrant00]

When I get home from this round trip i think im going to pull the motor and tranny with the backhoe and do some dissecting and see if the rotation of the transmission has been swapped. The railroad doesn't understand my new found boat obsession and has been keeping me from my new project!! If it hasn't been I found a number to a fella that deals with these trannys and maybe he has a "kit" for the task. Who would have ever thought that I get a boat with a brand spankin new motor with assembly required & Its the wrong darn one!!
Guys I really do appreciate all the help and feedback!

 

[CrazyFinn]

That's just part of the fun of getting an old boat going again. If there were no challenges, everybody would do it - and it wouldn't be as satisfying when you do finally get it going!

 

[alldodge]

That tranny will operate in either direction, the only issue is if it will have an issue spinning in one direction more then the other.

 

[alldodge]

Look on the transmission for the number and model. Being a direct drive it should be one of the ones below

 

[Comogene]

It appears your original engine was an "opposite rotation" or RH rotation. The transmission is a direct (1:1 ratio) Paragon "PM10" set up for right hand rotation, thus the designation of PM10R. If I recall, this Paragon series was set up similar to some BW Velvet Drives and all you have to do is reverse the fluid pump in the transmission. The factory sets them up and then designates which direction they are set to turn. When you separate the engine from the transmission you should see some arrows embossed into the metal with notations of "RH" and "LH". Loosen the bolt and turn the pump to the "LH" designation and bolt it back up. If you can, change the tag on the transmission to read "PM10L" for the next owner.

You will need to get a new prop.

The original engine may well have been set up as RH so that its torque offset some weight on one side of the boat. Maybe not but typically not a big deal.

While you have it out of the water and the prop off, you may want to check and possibly change the cutlass bearing the shaft strut.

Then go boating!!

Gene

 

[Jeffgrant00]

This weekend I am going to dive into the transmission and see just what I have, ill try and post some good pictures.
On a side note, I found a 79 with the factory hard top that runs 5 hours north of me for 500$!!!!!!!!!!! If he still has it on my off day im going to attempt to get mine off the trailer and go get that bad boy. My wife will be so proud! Ha ha