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Motor Shaking/vibrating

IMO it depends on what options he comes down to. If it gets down to new/different engine as the other option he doesn't have much to lose giving it a try.
 
I went by to get the pic of it but the HB was installed so the keyway wasn't visible and they were working on other vehicles. I spoke to the head mechanic and told him about the step down key and told them granger had them. He said he would mic the keyway and see how bad it is since he had another guy working on it yesterday. He said he gets stuff from granger all the time but didn't know they had them. So I'll see what he finds on Monday.
 
I would JB weld a keyway before I would have someone weld on the crank. Myself personally, would inspect the main webs for cracks and if they look good, would replace the crank. 97-98 I believe, seemed to be the worst years for main web cracks. So even if they weren't cracked before, they could be now. I would want to know before I was 500 miles from home to have it let loose. Or get a motor from Teds, if he's still doing that. If that balancer was just done a year ago, did you torque it? I think it's 200 ft.lbs. it should be torqued to?
 
Rodd said:
Well the diagnosis is a sheered off keyway. That isn't the worst of it, The keyway in the crank shaft was elongated so now the key is too loose. Any tricks to fix that?
Click to expand...

Good luck getting a keyway recut at a machine shop. Weigh the cost of doing this with the best possible chance of fixing it vs. cost of replacing the crank/engine.

How was the engine with blowby etc? Depending on what you want to do with the vehicle and said condition it may not be worth the repair if it needs to come out soon anyway.

If all else fails I have a crankshaft in the garage if you need it. I would have to check the thrust bearing measurements on it as it was loose in the MT block it came out of. They are a PIA to ship.

Are you doing any of the work yourself or paying a shop to do whatever including pull and fix the engine? Doing it yourself means you can take more risk because the labor cost is your time.

Note JB weld doesn't hold very long even on a 454. Friend pulls the balancer and redoes it every 6 months when his truck starts shaking again.
 
I just got it back. It runs find so far. They jb welded the key in and put red locktite on the bolt and torqued to 200 ft lbs. We'll see how long it lasts. When it gives out I'll either replace the crank or put in a p400, depending on where I am financially at the time.
 
I think the HB is going out again. I noticed a slight vibration today and the past few days it has taken longer to start than normal. The same symptoms as the last time the HB started going out. I watched the HB for about a minute and didn't notice anything. On Saturday I decided to clean up some oil from my power steering leak that was fixed last year. I sprayed some purple degreaser and hosed it off. I'm wondering if that could have caused it to loosen up. I thought that the only thing that could cause the red locktite to fail was oil. There was no oil on or near the HB. Also could I ensure alignment and attempt to retighten? What are your thoughts?
 
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That doesn't sound good. But you got 5 ish months out of Jb weld. Hate I missed the original! Just playing devils advocate for what might have lasted longer but would have been a try as well. I would say this would be a quick fix.

Would using a better product say loctite 660 in combo with a Fluid dampener have lasted 1-2 years or more. If my understanding is correct the fluid dampener has silicone inside and isn't a hard "timed" balancer and maybe softer loading for torsional load?

Again Sorry I missed this originally and hind sight is always better just was thinking I would have suggested this. Loctite 660 key way repair, new bolt factory torque with loctite, Fluid dampener. But the combo would have been the ticket. It would have been a gamble the extra cost of fluid dampener and and possible loss of reusable expensive dampener ( could be reused if not damaged on a new crankshaft or different motor). But at the time would have been cheaper than new crank or engine and an affordable shop repair not expensive take out/rebuild work.

Now its good money after bad if you want to try it knowing its an expensive bandaid.

Judgement call maybe I would recommend this for a loose keyway maybe not a sheared key and slipped balancer just depends on timing and overall feel of why key failed.

I have a 72 Ford tractor with a front axle with knees and spindle. The steering arm is held on with bolt that that helps lock the arm to spindle and there is a woodruff key to time the spindle and arm. The woodruff key way was wallowed out and some play in steering. I used loctite 660 on it with new woodruff key and it has held up well. Also put new grade 8 bolt on it and tighten it up. The thing takes a beating but so far no wobble in spindle. Not going to last a lifetime but inexpensive and works for an old tractor.
 
Thanks guy's! I think it's time for a scat crank from Leroy. I have almost 250k miles. Just wondering if it would be better to swap the motor. The difference is $2k to replace the crank and $8-9k for a rebuilt. That's paying to have it done. Never done either, not sure if I want to take on either project myself.
 
trying to find a shop who really knows these diesel engines is the same as looking for that needle in a haystack. JB Weld is a temp fix at best: just to get you home. if a shop suggested it to me(same thing for not using a perm fix like step keyway), i would be calling the tow truck to visit shop # 2.
sorry to hear about your problems but hopefully this can help another soul later in life.
the 6.2/6.5's are light duty, will never live up to the expectations of a purpose built engine and will always be plagued with problems: but at least we know what they are. if one component goes out, the whole system gets compromised. too many stories have been written and many more will follow.
 
Check to see if that is it. Another "fix" could be getting it in place then using the duramax repair kit where you drill the crank and balancer then install a round pin. I'm not normally found of things like this for repairs, but with that many miles on the engine, it would need a complete rebuild. And at that point I think you are better of with a military take out from teds or boyce.

Rather than the $8-9 k price tag for rebuilt- buy a new p400 from Leroy and reuse your IP, etc. Then it would be rock solid for years to come on the long block. only pmd/IP to sweat.
 
Rodd said:
Thanks guy's! I think it's time for a scat crank from Leroy. I have almost 250k miles. Just wondering if it would be better to swap the motor. The difference is $2k to replace the crank and $8-9k for a rebuilt. That's paying to have it done. Never done either, not sure if I want to take on either project myself.
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$8-9K for rebuilt... Are they fing kidding?! :eek: A Brand New Longblock Optimizer is only $6850.00 http://leroydiesel.com/products/amg-optimizer-long-block/ . A P400 is a buck under $8k and needs a different oil pan. http://leroydiesel.com/products/p400-6-5-long-block/

@Burning oil

Frankly a crack prone GM casting is replace what broke as they are NOT worth the machining costs and likely cracked in the mains anyway. Myself I would consider a used crank IF the mains are not cracked.

As I predicted JB weld is worth 6 months. :p
 
I was referring to Leroy's p400 for that 8-9k. I just drove it today and had no vibrations. Is it possible to have an intermittent HB problem?
 
Rodd said:
I was referring to Leroy's p400 for that 8-9k. I just drove it today and had no vibrations. Is it possible to have an intermittent HB problem?
Click to expand...

That makes more sense. Yes it's possible the HD (it's a damper not a balancer) can move around and then lockup if the keyway is damaged/loose again. You can start there and see if it's loose, but, start troubleshooting over otherwise.
 
Thanks guy's. I looked up the dmax fix and that looks like an easy fix. Has anyone tried it on a 6.5?
 
Maybe ask in the Dmax section or call a shop and find out what diameter the crankshaft is on the dmax. If the crankshafts are different diameters then the drill guide will not do you any good...you would have to lay it out and drill it free hand or make your own guide (in either case there would be no point in shelling out $180 for a kit when all you could use out of it was a dowel and a drill bit)
 
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