Can't turn engine after new bearings?

[garrettohio]

I put new pistons and rings and connecting rod bearings.i ordered standard bearings but don't think there right.now won't turn.

 

[fc1]

Did you/can you plastigauge?

 

[garrettohio]

Did you/can you plastigauge?

I see what I did wrong.the bearings sent was 17311-22970 .those are oversize bearings and thicker than standard ones ain't they.

 

[TheOldHokie]

I see what I did wrong.the bearings sent was 17311-22970 .those are oversize bearings and thicker than standard ones ain't they.

The bearing in your picture is .25 mm (.010 in) UNDERSIZE.

The 17311-22970 number is for a .5mm (.020") UNDERSIZE bearing.

And that mixup will sieze the rods.

Dan

 

[garrettohio]

The bearing in your picture is .1mm (.010 in) UNDERSIZE.

The 17311-22970 number is for a .2 mm (.020") UNDERSIZE bearing.

And that mixup will sieze the rods.

Dan

Looked at parts book and should have ordered 17311-22310 std size ones.i stoped when couldn't turn crank so all I got to do is pop the caps and put correct ones in.didnt continue assembling rest of engine

 

[TheOldHokie]

Looked at parts book and should have ordered 17311-22310 std size ones.i stoped when couldn't turn crank so all I got to do is pop the caps and put correct ones in.didnt continue assembling rest of engine

The bearing in your picture does not look to be standard. Its .010 under size. If that's what you took out and you put standard bearings in you will have loose rods (knock) and little or no oil pressure.

Dan

 

[TheOldHokie]

Looked at parts book and should have ordered 17311-22310 std size ones.i stoped when couldn't turn crank so all I got to do is pop the caps and put correct ones in.didnt continue assembling rest of engine

Absent a micrometer and dial bore gauge plastigage is your next best friend. Flying blind is dangerous.

Dan

 

[garrettohio]

The bearing in your picture does not look to be standard. Its .010 under size. If that's what you took out and you put standard bearings in you will have loose rods (knock) and little or no oil pressure.

Dan

That's the new one I ordered.i ordered wrong part number.old one I took out was marked std.i thought I ordered standard when installing them.but nope that was my mistake

 

[DanDavis]

Is it the lubricant thing? If the engine is not well lubricated, it may cause parts to seize.

 

[Fedup]

Is it the lubricant thing? If the engine is not well lubricated, it may cause parts to seize.

You do a lot of engine rebuilds?

 

[Flintknapper]

You do a lot of engine rebuilds?

Haha.....

Yeah, who would have thought that engine lubrication would be important. Surely the OP used assembly lube or at least some oil on the bearings.

Looks like the OP has already figured out he has .010" oversize bearings to accommodate a crankshaft that has been turned and polished.010" under. He just needs std. bearings.

 

[lmichael]

Yeah that will do it. Remembering my old dealership days. One of the other techs rebuilt his 69 Z28. Did the same thing. But he insisted "oh it's just a little tight" so he had another guy do the push start thing. It finally fired (barely) then the noises coming from it. Well let's just say, "sad" very sad

 

[TheOldHokie]

Haha.....

Yeah, who would have thought that engine lubrication would be important. Surely the OP used assembly lube or at least some oil on the bearings.

Looks like the OP has already figured out he has .010" oversize bearings to accommodate a crankshaft that has been turned and polished.010" under. He just needs std. bearings.

Read his response again. He has .010 under bearings on a crank that has not been reground and is still standard.

Dan

 

[Flintknapper]

Read his response again. He has .010 under bearings on a crank that has not been reground and is still standard.

Dan

Correct.

And the proper terminology for the bearings he has IS as you state.

"Undersize" rod bearings (more material on the surface facing the crank journal). Physically it is an oversize bearing to accommodate the regrinding of the crank.

Under and Oversize designations simply refer to which side of the bearing the extra material is on. Both are literally 'oversize' physically.

Of course the OP needs neither (assuming his crank journals and rod ends are OK) and just needs to go back with standard bearings.

 

[TheOldHokie]

Correct.

And the proper terminology for the bearings he has IS as you state.

"Undersize" rod bearings (more material on the surface facing the crank journal). Physically it is an oversize bearing to accommodate the regrinding of the crank.

Under and Oversize designations simply refer to which side of the bearing the extra material is on. Both are literally 'oversize' physically.

Of course the OP needs neither (assuming his crank journals and rod ends are OK) and just needs to go back with standard bearings.

If you spin a bearing or beat the big end of a rod out you do not fit "oversize" bearings. You cut the caps and hone the bore back to stock size.

If you spin a rod or main bearing and ruin a crankshaft journal you regrind the crankshaft and fit an undersize bearing.

For a machinist oversize and undersize always refers to bearing diameter not wall thickness.

Dan