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Discussion Starter #1
So I have heard 2 schools of thought both of them from factory service manuals.

One says torque the main bearing web bolts to a set torque,

But the other says torque them to a specific torque THEN go another 90 degrees.

My question is, I have the 83 6.2, it has cracked webs like most of the others and I don't want to let my crankshaft break free.

What do you guys say about the main bearing problem? How does the military do it and did the military have a history of losing crankshafts? What is my best bet for longevity?

I just got a new set of main bearing bolts from the manufacturer that are marked 10.9 same as the ones from the crank and I was told they are tty bolts. I'm just confused if it's tty why is there a hardness? Or is that how it works.

Any help is appreciated!
 

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This is per the GEP engineers......

All the crank, rods, head bolts are tty, somewhere along the way someone did the tty way, then found the torque value , that's easy to find, it is more common/easy for the average person to follow directions for a torque value, so that's how it was written, for ease of use.... every little bit of info wasn't printed, just the highlights... And most of the bolts are hard to locate anyway and they are nearly never used because GM & military never rebuilt motors they just replaced with another crate motor, they would do head gaskets but if it needed more out it came...
 

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Discussion Starter #3
I read that GEP took over for detroit and fixed the casting problems, could it be their blocks could handle the tty torque? N

What do you recommend I do with a block that is cracked? (I've inspected it myself)
 

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Short of going with "splayed" caps their isn't much other than the factory tightening recommendations..

Splayed caps are available, they require a trip to a machine shop ....
 

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Set torque
 

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Ive always torqued them to spec in 2-3 steps. Havent had one fall out yet! Went studs last time though...
 
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Discussion Starter #11
The arp stud kit? I heard it wasn't designed by them at all and even when i emailed them asking them if they had one they said they didn't... I would like to go with studs but I was told the arp kit being sold is too short and threads have even been pulled out.
 

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I didn't buy a stud kit for a 6.2. I bought a head stud kit and a main stud kit for a Ford Pinto. Worked great! Engine is still in the truck, so that's something. One is the long studs for the inside, the other is the short studs for the outside. I also put a girdle in.
 

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Kinda looks like 365$ us.

ARP’s page sucks and they don’t show the mains anymore but I found listings under other diesel shops.
 

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Discussion Starter #15
That's fine the original bolts were under $200 I'll replace the bearings and bolts and run it. This motor has been through a lot but has survived.
 

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Discussion Starter #16
So reading the fsm it says inner 100 ft lbs and outer bolts 110 ft lbs? I thought it was the opposite??

Page 2-28

The 6.2L diesel engine
GM 16015-05-1C
 

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Yes that is backwards, 110 inners 100 outers
 

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I was always taught to torque in equal increments until you reached the final value. In the Navy we did rebuild GM 6-71 diesel engines.
 

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1993 chevy silverado c3500 crew cab dually
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3 step it. Probably 35, 70 and final, start on center and work your way out.
 
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