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22r engine build problem - rod bearings

8K views 7 replies 5 participants last post by  Dirtdragon 
#1 ·
I've got a 22r that I'm rebuilding to use with a camden blower.. Just spent $650 on friggin' 8.5:1 forged pistons, so I want to get this darn thing right.

Had the crank checked at a machine shop. Turned out fine, so they polished it and said it was STD/STD size. I assume that's main/rod bearing size.

Ordered a set of engine bearings from www.engnbldr.com - he seems to know a bit about 22r and has had good recomendations. Anyway, I install my crank and main bearings, everything is fine. Crank will turn by hand. Install the pistons, everything is OK, I can turn without major effort.

Now I torque the rod bearnings down, even if just on one rod and the thing will barely turn and requires major effort. So, I supsect that I've got oversized rod bearings on a motor that doesn't need them.. Any other guesses?

I checked the old rod bearnings, other than being a different brand, they are marked STD. The new ones are marked .25, which doesn't particularly make sense.... Maybe I just didn't get what I asked for.

Any way to measure these guys other than plastigauge?

-d

OLD:
Fm
3950CPA
PU
STD

NEW:
C4129 AM
8E 0.25

Maybe .25mm = .010 over? hmmm...
 
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#3 ·
The bearing Ted sent you are wrong for your crank journal diameter, mistakes happen. Your crank is standard, the rod bearing @ .25 is .010 under (larger to make up for the cut) call Ted and have std's sent. He'll handle the problem precisely, quickly, and professionally.
 
#4 ·
Your machine shop should of asked for the bearings when they worked on your rods. A good machine shop can adjust bearing clearance and crush when they resize the large end of the rod. You will still want to check it before assembly though. like Tim said - everyone makes mistakes.

I just spend $550 on a set of Toyota diesel pistons. Will be a $2500.00 motor when I am done. I sleep good knowing all clearences are where they should be. Your motor is even more crucial and less forgiving then my 4,500 RPM diesel.
 
#7 ·
I had the machine shop check 'em all. They all came back std, well within limits. No scoring that I could see. I just had the crank polished.

It turned out that the bearings I was sent were sized wrong. You couldn't tell by looking at them.

Engnebldr sent me a new set, correctly sized, the next day. No cost. Didn't even want me to send the old ones back.

-d
 
#8 ·
Your right Tim ,plastigauging is not the most accurate approach it will tell you if the machine shop or the parts store screwed up.:rolleyes: hopefully the machine shop used precision tools to tell you what bearings are needed,after the crank has been cut or polished
 
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