Crank Pulley Sizes

amanco · Post by **amanco** » Fri Oct 10, 2008 1:31 pm

Any one ever notice two different styles of crank pullies? Both are T-245 engines. I suspect one is a replacement engine.

Notice location of the timing pointer on both engines. One is a lot coloser to the edge of the cover and has the corner cliped off and is set for a larger pulley. The smaller pulley is held on by the crank nut and a key on the crank. The other by 6 bolts. What do we have here???

Here compares both crank pullies.

gwalker · Post by **gwalker** » Sat Oct 11, 2008 3:24 pm

One may be a car engine, the 230 appeared in all chrysler products of the time, but some diff. occured between cars and truck applications. One is the very head itself which has a letter cast into it on the top toward the back denoting the div. it was made for: DT was dodge truck, D was dodge, P was plymouth, C was chrysler an I think DS was desoto.

amanco · Post by **amanco** » Sat Oct 11, 2008 8:09 pm

I am sure it is an M37 engine. It has the DT head and bolt on oil filler tube. I tend to believe it has been rebuilt twice, once by the military and once by a civilian company. The military rebuild tag is missing but the rivets are there and you can see where the tag was. The civi rebuild tag is mounted on the top of the oil pan rail just below the distributor. The crank may have been replaced with a civi crank. That is the way I am leaning. My concern is will my 24V generator be spinning fast enough with the smaller civi pulley? Is there a recommended RPM for the generator? I have a mechanical tach I can check the running RPM of the generator if it has a recommended minimum operating RPM.

k8icu · Post by **k8icu** » Sun Oct 12, 2008 8:01 am

Is this the motor that came out of my truck? I know it was converted to civy distributor, but I didn't think it had any other modifications. Can you use the crank out of your old motor? Since the problem with that motor was the bock...maybe you can take the best of both and make one good motor?

amanco · Post by **amanco** » Sun Oct 12, 2008 12:30 pm

I think it is a replacement crank and the pulley flange from my old engine should replace the smaller civi pulley. The block itself is definitely a military block unless there were other applications for the bolt on oil filler tube. And isn't the T-245 designation specifically for the M-37 ?

I pulled the freeze plugs because one was nearly rusted thru. Made cleaning the inside alot easier. Got a new set of rod bearings ordered. Probably didn't need them, the old ones look ok, but since I have it torn down this far I said lets do it.

I just had not noticed the two sizes of pullies before and I was worried about the charging system if I didn't swap the larger pulley to it.

k8icu · Post by **k8icu** » Sun Oct 12, 2008 6:19 pm

Yep you have it down that far you might as well put new stuff in and make it good. Sorry about that I'm to much still the novice when it comes to M37s. Now 151s that's a different story with me...

Yeah just swap the crank and pully over from the other motor and build it back up...but you better get moving time is running out on you...

amanco · Post by **amanco** » Sat Oct 18, 2008 12:59 pm

Here are the two styles of crank flanges. The one on the left is the stock M37 flange. The pulley bolts on to it. The one on the right is the civi version. The pulley is part of the flange. Both styles are held in place with a key and the crank bolt.

I am just going to swap the M37 flange so I can stay with the much larger pulley.

So now we all know there are two distinct different styles.