Washed my main caps with very hot water, practically boiling. Will this make them expand? I ask this because I dropped my main caps on, and they won't fit into place anymore!! I know some of you might be getting upset with me but please don't bash me on this. Do they require tapping them in? Anyone else had this problem? I fit tab to tab, I am pretty sure I have them in the right order.

I guess you can't really see the number but do you see what I mean about them not falling in place.

 

You have not done this before is that correct?

 

I have never built an engine.

 

are you using a service manual? If not you for sure should.

Did you use assembly lube on the bearings? I am not sure on using studs but with a small block Olds and main bearing bolts the torque specs are 70-80 and the rear main is 100-120 per Motors service manual.

you should be installing them dry and measuring with plastigauge to ensure proper clearances,

The GM shop manual for small blocks with bolts says 1-4 mains tighten to 80 ft lbs. and #5 to 120 ft ibs this might be different with studs.



when you tighten these using alternating tightening you will see they will seat. But, learn to plastigauge it is important.

Hope this helps
Larry

 

Thanks Larry, yeah I bought plastigage today, I bought the red ones. Read on another thread the clearances should be .0035 down to .003 I believe but I am gonna double check. Yeah torque with studs is 110. Thanks again, didn't know they'll seat after tightening I just didn't want anything to break, being careful.
Have Federal Mogul assembly lube. Using Bill Trovato's youtube video to guide me in building it.

 

 

 

Main cap torque sequence? Or a link to these and more?

 

 

Was this engine taken to the machine shop and checked/machined or are you just cleaning up it up and replacing bearings?

 

Took it to the machine shop got it cleaned bored honed. Took the crank and got it polished and mic'd. He told me to use standard bearings so I did.

 

Washing your main caps in hot water will expand them only while they are hot. The main caps fit very tightly so a plastic faced hammer may be needed to seat them. A steel hammer can cause damage. And don't tighten the nuts to seat them because if you tighten one side too far it may cause damage to the cap, the block, or both.

Don't be scared by this. If you are doing a simple rebuild/refresh and not planning to thrash on the engine it can live a long and productive life. There are literally millions of engines on the road with questionable tolerances but you need to find out if your tolerances are acceptable. If, however, you are planning to do any kind of performance driving, you should get things checked or learn what and how to check yourself. The tighter torque values used by the main studs and, I'm guessing here, new rod bolts will distort the caps a bit differently than the factory bolts. So they need to be checked or reconditioned to work with the new hardware.

 

^^This^^
If the crank was turning when you took the engine apart, and it isn't bent, and you are using the correct size bearings, then there is no reason at all that the mains caps won't go straight back on.
If you are building the engine to get lots more power then yes, you should have everything checked for perfect alignment and clearances, in other words have it blueprinted.
When the engines were assembled new on the production lines the component parts were simply put together, they would have passed quality control, and some would have loose clearances, others tight, but all within the allowable limits. Then nearly all these engines, no matter which make they were, would give reliable service for many miles. Certainly if you assemble it carefully it will make it a lot further than round the block!.

Roger.

 

 

Get the big ends of the rods resized and an align hone on the mains, Cutlassefi is bang on. Your tune will also have to bang on or it will be a pinging nightmare.

 

 

Tune as in fuel mixture and timing.