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Re: In need of a CCKA short block.

Posted: Mon Oct 16, 2023 7:39 pm
by MattA
Sounds like your making good progress 👍

Re: In need of a CCKA short block.

Posted: Mon Oct 16, 2023 8:21 pm
by JSinMO
Sounds like you about have it wrapped up! I hope to here you have it run again soon! :thumbsup:

Re: In need of a CCKA short block.

Posted: Mon Oct 16, 2023 9:40 pm
by Spike188
@metalguy[ You mentioned tappering the Lovejoy coupling. Your intention may be to grind the shaft and leave the coupling straight. For others reading this, lovejoy couplings are designed for straight mounting only. Case/Onan shafts are 1-1/8" diameter. I put a Performer P220G shortblock from welder in a 448. The shaft was tappered. Cleaning it up required grinding the tapper down to 1" parallel. Lovejoy halves are sold separately making it possible to match a half to the shaft size.

Re: In need of a CCKA short block.

Posted: Tue Oct 17, 2023 6:39 am
by DavidBarkey
@metalguy I not sure if I mentioned it before but the P220 with the tapered shaft I have . When I cut the taper in the love joy I also cut a small countersink releaf to accept a thick flat washer with a tapered centre for a 3/8" flat head cap screw to maintain the lock on the shaft . It was done to fit under the spider . Also cut a key way into the taper parallel to the centre line of the crank to match what was let of the keyway in the lovejoy . I used a coupler that sized with the small end of the taper . Can not remmember if it was 7/8 or 1 " There is documentation on this on this or the old sight , sorry can't remmeber which .

Re: In need of a CCKA short block.

Posted: Tue Oct 17, 2023 2:41 pm
by metalguy
Spike, I am currently using a tapered lovejoy I modded for the last tapered shaft ccka I installed in my first 646 with no issues. I see no reason why it would be a detriment at all. ------Metalguy

Re: In need of a CCKA short block.

Posted: Tue Oct 17, 2023 8:58 pm
by Spike188
Lovejoy are only manufactured for straight shaft installation. Lovejoy specifies minimum gaps between opposing shafts and Lovejoy faces. That is because there intended use was for field instalation where shafts are often misaligned. In some cases of extreme torsional loading and start/stop forces are high the rubber will fail.

Dave's method of machineing a step in a coupler half to except a bolt/washer to ensure a tapered LJ stays on a tapered shaft. Another method is to machine a keyway in the LJ that is tapered negative to shaft keyway and driving a tapered key into the way, wedging the coupler on the shaft.

Case pump/engine combinations are tame beasts. Shaft alignment, and torsional loading are all very well below the forces that Lovejoys are designed for. A good machinist can match tapers and have longevity in the fit. A sloppily ground straight shaft is forgiving when matched with a Lovejoy, and JB Weld.

Re: In need of a CCKA short block.

Posted: Wed Oct 18, 2023 10:11 am
by Spike188
Some boring reading can be found here. Unfortunately there are no pictures.

https://www.lovejoy-inc.com/resources/t ... -handbook/

This section discusses mounting to a tapered shaft.
One of the tapered applications described is similar to a compression ferrule inserted inside the coupling.

https://www.lovejoy-inc.com/resources/t ... 92ce194e07

The end plate and bolts or nut will serve to prevent axial movement under loads. Tapered shafts are used for ease of maintenance. A popular tapered shaft device is the mill motor that uses a standard tapered shaft with key.

Re: In need of a CCKA short block.

Posted: Wed Oct 18, 2023 9:17 pm
by Spike188
@metalguy I noticed my first reply is in red. That was not intentional and can't find font color choice on my phone. Except my apologies.

My question is how you are holding the tapered Lovejoy on the shaft. Are you using a setscrew against the original key?

Re: In need of a CCKA short block.

Posted: Thu Oct 19, 2023 3:13 am
by metalguy
Spike, I am holding the lovejoy on using a key, and set screws. I ground a flat on the key for the set screws to seat on. ---------Metalguy

Re: In need of a CCKA short block.

Posted: Thu Oct 26, 2023 1:52 pm
by metalguy
I used the set screw, and also fabbed up a stepped washer that allowed me to install a bolt into the end of the crank as well. The engine is now setting in the 646, and only fuel, and wiring to finish up! ------Metalguy