What does the chamber tell you?

Lem Evans wrote:

cool40 wrote:

Lem Evans wrote:

cool40 wrote:

rmcomprandy wrote:

cool40 wrote:I'm fairly confident the oil got by the rings. I suppose the lack of fuel and too much timing,37* contributed to the problem. The bearings all show wear but not necessarily detonation related as top half look better than bottom. If a main bearing was a little tight would it be possible for the rod bearing to spin from not enough oil but the main survive? I still can't exactly pin point the reason for rod bearing failure on #1.

That rod cap sure shows excessive heat which probably came from the failed rod bearing.  Clearance not proportioned correctly or temporary lack of oil to cool it or distortion of the rod big end ... something to cause the overheated rod bearing.

after polishing the crank I put the mic on it and found the #1 journal to be about 4 tenths bigger toward the radius and I can only assume it was that way before also. It's got .003 now and the others have more,.0035 being the most. The mains were .003 before would .004 be out of line for a high rpm deal with straight 30 weight or 20/50? The heavy steel rod probably don't help things.

I'd damn sure want .0035"-.0036" on the mains.

You get that taper out of the  #1 journal?

working on it. I got +.001 main bearings to put it @ .004.

I've often used 1/2 std. and 1/2 +.001" to get where I wanted to be.  Which main bearings are you using?

cool40 wrote:

Lem Evans wrote:

cool40 wrote:

Lem Evans wrote:

cool40 wrote:

rmcomprandy wrote:

cool40 wrote:I'm fairly confident the oil got by the rings. I suppose the lack of fuel and too much timing,37* contributed to the problem. The bearings all show wear but not necessarily detonation related as top half look better than bottom. If a main bearing was a little tight would it be possible for the rod bearing to spin from not enough oil but the main survive? I still can't exactly pin point the reason for rod bearing failure on #1.

That rod cap sure shows excessive heat which probably came from the failed rod bearing.  Clearance not proportioned correctly or temporary lack of oil to cool it or distortion of the rod big end ... something to cause the overheated rod bearing.

after polishing the crank I put the mic on it and found the #1 journal to be about 4 tenths bigger toward the radius and I can only assume it was that way before also. It's got .003 now and the others have more,.0035 being the most. The mains were .003 before would .004 be out of line for a high rpm deal with straight 30 weight or 20/50? The heavy steel rod probably don't help things.

I'd damn sure want .0035"-.0036" on the mains.

You get that taper out of the  #1 journal?

working on it. I got +.001 main bearings to put it @ .004.

I've often used 1/2 std. and 1/2 +.001" to get where I wanted to be.  Which main bearings are you using?

I have a set of speed pro std and federal +.001 I can mix probably .

Lem Evans wrote:

cool40 wrote:

Lem Evans wrote:

cool40 wrote:

Lem Evans wrote:

cool40 wrote:

rmcomprandy wrote:

cool40 wrote:I'm fairly confident the oil got by the rings. I suppose the lack of fuel and too much timing,37* contributed to the problem. The bearings all show wear but not necessarily detonation related as top half look better than bottom. If a main bearing was a little tight would it be possible for the rod bearing to spin from not enough oil but the main survive? I still can't exactly pin point the reason for rod bearing failure on #1.

That rod cap sure shows excessive heat which probably came from the failed rod bearing.  Clearance not proportioned correctly or temporary lack of oil to cool it or distortion of the rod big end ... something to cause the overheated rod bearing.

after polishing the crank I put the mic on it and found the #1 journal to be about 4 tenths bigger toward the radius and I can only assume it was that way before also. It's got .003 now and the others have more,.0035 being the most. The mains were .003 before would .004 be out of line for a high rpm deal with straight 30 weight or 20/50? The heavy steel rod probably don't help things.

I'd damn sure want .0035"-.0036" on the mains.

You get that taper out of the  #1 journal?

working on it. I got +.001 main bearings to put it @ .004.

I've often used 1/2 std. and 1/2 +.001" to get where I wanted to be.  Which main bearings are you using?

I have a set of speed pro std and federal +.001 I can mix probably .

134M?

I wouldn't use the straight 30 wt,