Ok I have all my stuff back from the machine shop. The motor had 40k on it, and I tore it down on the advise of a buddy. Well the machine shop did a hone and deck, clean and mic'd everything(as requested) and gave it back to to put together (again as requested). Now do I still need to use plastigage, or can I go ahead and assemble it as is, torqued to spec. I sure don't want to question the shops integrity, as they are well respected, but am curious. Thoughts?
ALSO... they are std size bearings and std rings. No cutting done. The old bearings were mint.

 

It's always a good idea to chech bearing clearance. If not a bore guage and mics then plastigage will work too. check it out. Better safe then sorry.

 

It's known as "poor mans mic set" with some of the gearheads at work.LOL
There's nothing wrong with using it unless the motor is for some sort of hi-performance out put.
Some may advise using a mic set since they are more acurate.
Nothing against the shop--it's a self security thing.

 

I was just reading this and would say yes, double check everything. Skip to post #75 and read how things went along>>Link

...or skip to these two posts:
Link 1
Link 2

 

i have used plastigage for years . it may take a few more minutes to check all . BUT do it . it may save you severe problems , or it may just prove all is O.K. . good luck .

 

Hmm. Ok I believe everything was checked/rechecked at the shop, with the right tools ie: mics, and calipers...
t/y

 

also motor oil on the rod/main bolts too right?

 

And nothing at all on the back side of the bearing shells. Clean and dry to the block. Plastigage is a good final check I think. There are stock bearings available that are .001 and .002 OS for a crank that's a bit undersize.

 

You mean when you use the plasti?? No- you do that on dry bearing surfaces-no lube. Don't turn the crank with the plasti in. It'll make more cleaning for you, besides smearing plasti, you'll have to do it over.It is IMPORTANT that all bearing surfaces are clean & grit-free!!
After you CAREFULY remove the plasti & you're ready for assembly, then you final-assemble with motor oil or some assembly lube for engines.
(edit)
To remove plasti, use a finger nail or a popcicle stick.
You don't want to gouge//scratch the crank!!

 

how much did you spend on the engine

how much time will it take for you to physically see that all is well

dont skimp when putting the motor together

check the ring gap

put all the rings on the pistons and then recheck

ask your machine shop about the motors they put together with a warranty if they use plastic gauge

 

Sounds like you need to stop listening to your "Buddy". He advised you to tear down the engine with only 40k? The old bearings were mint?

Mercy.....

 

Even GM's 96 FSM says to and shows how to use Plasti-Gauge. As already recommended, Yep, check everything.

Jake

 

Well, thanks to all for the thumbs up on the plastigage. Here is what I show using standard size clevite main bearings, on a polished 40k crank, torqued to 75 lb/ft. They are all within the red .002 block. So whatcha think? Thanks again

 

I would suggest using cast rings as well

if you had a fresh bored block you might get away with molly

cast is more forgiving in the seating process

 

I am using std hastings brand cast iron rings, though getting the oil ring to go into the bore is giving me he11. So the .002 on the plastigage is good?
t/y

 

Yes, .002" is GOOD TO GO!

Hang on a SECOND!

Since the bores were horned by the shop, you need to know what rings they were honed for. That's critical for ring seating. If the bores were honed for moly rings, use those. Call your shop.

Jake

 

will check in the am, although i did have them do the buying for the rings and the bearings, as though they were building it. Again to motor had few miles and was only honed for the sake of new rings. Was gonna let them build the short block, but i been wanting to build one for a long time.
"HERO OR ZERO AT THE TURN OF A KEY"

 

Good. I'll bet that since the shop did both the honing and selecting the rings they ordered and gave you the correct ones.

For the benefit of others, you can't just change the type of rings like you would socks. Moly rings call for a smoother bore finish and cast the opposite.

So if you install molys in a bore honed for cast, the moly wears excessively fast and can cause the moly to chip. In the other instance, a cast rings installed in a bore honed for a moly ring will have a seating problem because the bore finish is too smooth. Each type of ring has it's own wall finish spec provided by the ring manufacturer.

Jake

 

To plastigauge...or not. Here's how I see it. If you are absolutely positive that everyone along the supply chain, from bearing manufacturer, to machine shop, to you, is perfect and there is no possible way that anyone could have made a mistake, and you are willing to bet your time and money on that belief then, by all means, skip the plastigauge.

 

well for what it's worth I did "gage" the mains and the rods, and got .002-.003 for everything. The crank is in and spun freely, and with the pistons/rings installed it takes less than 30lb/ft to rotate the whole rig. Well under the 35-40lb/ft spec. Thanks to all.