6.2l crankshaft bolt thread size? (Balancer replacement)

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squaredeal91

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Working on an early 6.2 diesel maybe 81 or 82. Currently replacing balancer and I'm needing to find a longer bolt to install it. Does anyone know what the thread size and pitch is on the crank bolt? And even length in metric? If not I'll find out and post here what it ends up being. And hopefully save someone els the trouble.
Or am I trying to install this incorrectly? I'm doing it how I would a small block or big block.
 

squaredeal91

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New alternator pulley lol. Painted crank pulley and hardware.
 

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Old Guy Bill

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I don’t know the thread size but you really need the proper installation tool.
It will have a thrust bearing.
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squaredeal91

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Looks like 16mm X 1.5
Good call Bill, I think I'll call Napa and find out about an installation tool.
 

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backwoodsman

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The manual says to install it using a mallet, and tap it on far enough so the bolt can be installed. When I did mine, I heated it in the oven to around 170F (lowest oven would go) so it would slip on easier.

Torque spec is 140-162 ft-lbs.
 
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squaredeal91

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The manual says to install it using a mallet, and tap it on far enough so the bolt can be installed. When I did mine, I heated it in the oven to around 170F (lowest oven would go) so it would slip on easier.

Torque spec is 140-162 ft-lbs.
I normally tap on and pull method too but this one is too far away to even start threads. I ordered a tool of unknown sizes at Napa and will see tomorrow if it has this size in it because it doesn't say in description what sizes it has and the kit they stock skips over this size.
I suppose if I can't get the tool I'll try the oven method.
 

squaredeal91

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The tool that was ordered also skips over the size I need. At the hardware store I can buy the correct size nut but not the bolt. Pretty discouraged about it. I ordered a bolt that is much longer but it's on a slow boat from China lol and I don't think I want to wait that long. Might get froggy and put it in the oven and go for it.
 

backwoodsman

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You can't get it started by tapping? The manual doesn't mention heating it up, so it must be possible, but it's easier if you heat it. I figured 170F is within the range of normal operation so wouldn't hurt the rubber; I've heard of going much higher but don't think I'd be comfortable doing that. Don't forget to lube the shaft.
 

squaredeal91

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You can't get it started by tapping? The manual doesn't mention heating it up, so it must be possible, but it's easier if you heat it. I figured 170F is within the range of normal operation so wouldn't hurt the rubber; I've heard of going much higher but don't think I'd be comfortable doing that. Don't forget to lube the shaft.
I tapped it on a bit but it's pretty far off from even starting threads and theres not allot of swing space. Came off Harder than I expected but was as smooth as could be expected so I figured it's just tight.
 

squaredeal91

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Bolt came in and I finally got to it yesterday. The new bolt Only threaded half way down but I found this super thick spacer that fit perfectly and it pulled/pushed it on most of the way and then finished with original bolt. Worked smoothly and my belts are running smoothly now. New Sound when engine idles. Not sure what it is yet. Hoping it goes away. It's probably pissed at me lol. Engine has some miles but is happy for the most part. That setup worked so good I painted it and labeled it.
 

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