Page 3 of 14

PostPosted: Mon Jan 30, 2006 8:41 pm
by flyalaz
Assembly step 2

PostPosted: Mon Jan 30, 2006 8:43 pm
by flyalaz
Step 3 and pull!

PostPosted: Mon Jan 30, 2006 8:52 pm
by flyalaz
Done. Notice this bearing- It has a 9 ball race. It is an NSN bearing, sealed on one face. Does anybody else have this bearing on their motor? The other bearings are from a Spanish company, have 7 ball races, and are not sealed. This motor was always running a few hundred RPM's more than the other, and I wonder if the combination of a seal and more bearings contributed to this.

PostPosted: Mon Jan 30, 2006 9:11 pm
by flyalaz
Case halves before cleaning and touch up. Note the porosity in the metal.

PostPosted: Mon Jan 30, 2006 9:17 pm
by flyalaz
Another cylinder to refurbish as well!

PostPosted: Mon Jan 30, 2006 11:14 pm
by flyalaz
Correction to the bearing numbers:

.983" dia aft bearing= NTN 6205LU , only numbers I found

.788" dia fwd bearing= SKF 5304 "2B51" , or "2851", or "2R51", or "ZB51".
Hard to tell due to poor etching, made in Italy.

Anything familiar?

PostPosted: Tue Jan 31, 2006 8:00 am
by Shannon
Karl, all the bearings in the engines I've rebuilt were 7-Ball SKF 6304 JEM BF01's, made in Italy.

PostPosted: Tue Jan 31, 2006 11:14 am
by Shannon
Karl is your replacement crank a "large crank" ?

PostPosted: Tue Jan 31, 2006 6:57 pm
by flyalaz
Hi Shannon,

It's interesting to know that I might have a rare half breed engine! But, as the pic will show, this is what I have. The mag side is on the left, showing the bearing that goes along with it, and the prop side on the right. Both bearings are sealed on one side only, and they were installed so that the open side was facing outwards to be able to be lubed by the port in the crank casings. Dubious flow as there is only the inlet hole!
Only the mag side has the 9 ball race. Prop side has 7.
The replacement crank on the completed motor has the small crank. (both ends take the .788" dia bearing). Having never had a Large crank, (ENGINE that is!), I guess both ends would be .983" dia?

Blue skies,


PostPosted: Tue Jan 31, 2006 8:01 pm
by flyalaz
Part numbers found, cast on the crank lobe interiors, as follows:

Mag side- B7 CK60

Prop side- B1007 on one side lobe, 7227 on the other. Both interior face