Dragula

Anybody heard issues with these? I had one TOTALLY fail and subsequntly shred about .045" off the journal of my forged crank sending metal throughout my entire engine
Clevite said that it was probably due to inadequate oil supply, however, I always had good oil pressure, even when things came apart. Also, the rod bearing right next to it was in great shape! What gives? The engine only had 494 miles on it
So much for the internally balanced 383 which is a pain in the a$$ to get done!
Do you know if anything can be done with the crank. Can a machine shop weld and then re-machine that journal?

89gta383

iTrader: (5)

I hope not, cause I've got the same bearings in mine. Haven't started it yet though.

Depending on how much and how valuable your crank is will determine whether you want to have it welded or not.

If it's a 4340 crank, yes, but I don't know how much it would cost.

Did you measure the rod side clearance on each rod?

jcb999

It kind of plays a pretty passive role in all that.

If you had a good hydraulic wedge of oil.. the bearing never touches the crank.


I would have that rod checked extensively. Big end dimensions and straightness.
I think I would resize it just to be safe.

Fast3rdGen

gotta watch out for those big greasy thumb prints when you install the bearings. are you sure the bearing and journal surfaces were clean enough to eat off of except for asembly lube when you put it together?

Perry93TransAm

Did the engine detonate much? detonation will beat a bearing out in no time. this wouldnt happen to be # 8 would it?
Perry

Dragula

Everything was brand new, all tolerances checked, lubed, side clearances checked, cleaned......
I don't know what else, except for maybe the greasy fingerprints?
Everything seemed great during the build. Maybe I overlooked something. Who knows....maybe I jacked up and put the bearings in upside down. Would that do it?
No detonation......it was cylinder #3.
The big end of the rod still measures out okay, but I will probably have it honed to be safe. The 383 will have to wait a little while until I can get another crank.
I have a balanced 355 rotating assembly that I will put in it to pacify my go fast foot for awhile. (GM #442 crank reground 10x10, with forged I-beams....10.4 C.R.)
Soundls like from what y'all say it was most likely builder error......I can except that
I think this will be my excuse to build that 383 with the big blower on top

Guest

Unless it spun, you should still be able to read the back side of the bearing. Is it the same size as the rest? It should say STD or .010, .020, whatever the ones were that you used. I assume std.
Misboxes suck. Seen it happen.

Dragula

The bearing did spin, so the back can't be read. However, they were all STD bearings (I visually checked) since the crank and rods were new. I also plastigaged the bearing clearances as well as measuring.