ctreutel

Hi Guys;
I just completely rebuild my engine [1976 455] for my 1969 442. Bored .40 over, new pistons, bearings, cam, crank machined...everything new.

It takes 95 ft-lbs of torque [torque wrench on the harmonic balancer] to get it to turn over.

Seems high to me. I used assembly lube on all parts...and oiled the pistons and lifters when installing.

Is 95 ft-lbs normal ?

68442CONVERTCO

Are the spark plugs in?

chadman

X2 if not something is wrong. If so, remove them and check again.

ctreutel

Spark plugs are out.

Yikes...what is the correct torque?

gearheads78

Honestly I have never measured but that does seem high. I think of 90ft lbs to torque 1/2" lug nuts. Thats a lot.

droldsmorland

Is it totally assembled or is this just the short block? If totally assembled is it hooked to the trans and all the accessories in the front of the engine? If its just the short block rotating that hard Houston you have a problem. The Rotating assembly should turn with relative ease. If its fully assembled remember you have a new engine, rings, seals etc that will all have increased drag until break in. Thats why a new engine runs slightly hotter (sometimes) until broke in.

rjohnson442

did you prime it before turning it over for the first time? I'm thinking the crank is torqued down to tight though.

ctreutel

The engine is fully assembled...still on the engine stand, plugs out.

We put oil in the spark plug holes and let it sit, then got 95 ft-lbs to get it moving. Once moving it takes 90 Ft-lbs to keep it going. Turned 3 revolutions.

chadman

Try backing off the rockers and see what you get.

Sampson

I just finished rebuilding my 350. I did not put a torque wrench on it but I can tell you the effort to turn it over went up substantially after I installed the heads. Even with the plugs out. Gotta remember you are fighting the valve spring pressure and weight of the valve train as well. I am curious if someone else chimes in with some comparable torque numbers.

TripDeuces

That sounds very excessive. I would have checked it every time I torqued something down. As soon as it started to bind then you would know. I can think of a list of things to check.

Rod side clearance
Crank cut with a fillet and bearings are now binding
Thrust bearing not set before mains torqued. (Whacking the crank forward and back)
Rear main oil seal (Shouldn't be that tight regardless)
Oil ring rail on top of expander
File to fit rings not filed?
Bad line bore or bent crank shaft
Bent cam
Cam thrust button not clearanced (doubtful)
Valve spring coil bind

I'm sure you can think of more. I would expect it would be more in the 25-45 range at most just sitting on an engine stand.

ctreutel

Spent most of yesterday checking everything. As TripDeuces suggested, as I torqued things down, I checked to see if it was binding. Turns out the #5 main is the culprit. When I took the bearing cap off, the torque to turn the engine over dropped in half. After plastigauging the mains, it looks like the #5 bearing clearance is much tighter than the rest. [.0005 for #5 and .002 for the other bearings]. I am using green plastigauge, with a working range of .001-.003". I extrapolated on the #5 main to get the .0005 measurement as it was outside the working range of the plastigauge. I'm thinking that was a bad assumption on my part [clearance is probably zero].

Something is binding on the #5 main. So I'm going to shim the cap .006" to see if that solves the problem. Question is, should I take the crank and the block back to my machine shop? I had the block line bored and the crank machined to .030 under...so it should be perfect right??

droldsmorland

quote<"should I take the crank and the block back to my machine shop?">.....

NO! Id find a machine shop that cares enough to not let something like that go out the front door! Thats horrible machine work. You now see it pays to check it all out before you fire the engine. Nice catch. That could easily have gone very bad. I wouldn't recommend cutting a crank down to .030.,.010 is as far as I like to go others say .020. It depends on what the application is I suppose.

oldsmobiledave

Good catch on the bearing clearance. Old school plasti gauge to the rescue.

While that problem is being addressed I'll ask what heads are you planning to run?. If the stock original J heads that came with that 1976 engine now os a good time to find a '72 & older set of heads to install. Those J heads are junk unless they have undergone some major work.

Good luck with the project.

chadman

The #5 main is typically the loosest of the five mains. Definitely do some more checking and see what is the cause. I would mic all of the mains on the crank and check the main bearing bores with a dial bore gage. BTW .030 under is fine on the mains. That still leaves it at 2.97". A SBO is only 2.5" from the factory.

cutlassefi

For the most part I agree, find another shop but let them know you had to take it elsewhere.

There are a lot of misconceptions regarding how safe it is to grind a crank beyond .010 or .020.

Fact- Clevite bearing shells share the same amount of steel backing on std and .010. Then the shell is thicker for .020 and .030. So a .030 under bearing will have the same amount of support as a .010 under.
And many guys grind the journals to much smaller dimensions for the use of other rods etc with no issues.
The hardening of the journal surface only goes a few thousandths deep anyway. It's gone on the first regrind.

ctreutel

Thanks Dave!
I replaced the J heads with Edelbrock Performer heads [new cam as well]. That should make her go.

matt69olds

The #5 bearing is typically the loosest fit to keep the rear seal lubed (so I have been told). I think I would have a long discussion with the machine shop. Hopefully thy will work with you and make it right. Don't let them give you the "this is how we build our chebby engines" crap, Olds engines need more bearing clearance! If they argue or wont listen find another shop!

Whats the rest of the build? How deep in the hole are the pistons? Since it all has to come apart again might want to deck the block. Most aftermarket piston are short, leaving the piston deep in the bore.

cutlassefi

Sorry but there is some incorrect info here.

Octania

Good thing you caught it

Always turn the motor after each step of assembly, to keep track of how it feels.

When the crank alone is in, ideally you can spin it by hand until the rear main seal is in, and even then if you use the rubber seal.

The Bug Man

Did you use an old school grease rope seal or a new poly type. I had your same issue but mine was the old type rope seal. Threw it away and bought a new poly one. I could turn it by hand all the way through the entire assembly after that. It looks like you found at least most of the issue with the #5 bearing . Good luck

1970-W30

"So I'm going to shim the cap .006" to see if that solves the problem." To me that's a bad idea, it won't give you an accurate answer or solve the problem, like chadman posted, the only way is to mike the #5 main journal and measure the #5 main bearing bore, then you'll get your answer to the problem..

TripDeuces

Might help you or maybe not but I just checked the break away torque on my new short block. Less than one lb/ft to turn the crank over with seal. About nineteen lb/ft to turn it over with all the rods and pistons in it. No heads or valve train.