Tranny, starter, or something else?

[frank8003]

Sorry I would not use 4inch bolts to do the job anyway.

Nothing I have read makes me think that the flywheel is damaged. Now the man is unbolting the trans to replace the flywheel. It will not hurt to replace.

I could give many reasons for the engine not turning over. And to eliminate any trans problem I would just take out the torque converter bolts, keep it simple, Right.

Allot of assumptions and some good advice also. The flywheel tool, good that will tell him the condition of the flywheel, and if there is a clearance issue, loose bolts, cracked bolt flange. It will help with seeing if the engine is free to rotate, and the symptoms thereof.

I read in another thread about starting at the [top of the hill] when not paying attention to the start, how prophetic.

That was here?
post #2
https://www.steelsoldiers.com/threads/brake-issues.167598/

 

[cucvmule]

Yes it was, I thought that I would not take the credit from someone else, that stated a stone cold fact.

 

[14ghz]

I got the broken starter bolt end cleanly out of the block easy enough with a left-twist drillbit. One thing I'm wondering about now, is how do I rotate the engine and flex plate to unbolt it from the torque converter if it's bent and hitting the side of the bell housing? I tried putting a pry bar on the teeth but no luck, doesn't budge... If the starter was unable to turn it over, I doubt I will be able to by hand.

 

[dependable]

I got the broken starter bolt end cleanly out of the block easy enough with a left-twist drillbit. One thing I'm wondering about now, is how do I rotate the engine and flex plate to unbolt it from the torque converter if it's bent and hitting the side of the bell housing? I tried putting a pry bar on the teeth but no luck, doesn't budge... If the starter was unable to turn it over, I doubt I will be able to by hand.

You could undo the glow plugs as mentioned before to eliminate compression resistance. Then a little applied force or light prying. Also you can use ( I think it is 15mm) low offest or combo wrench, box end, to put on one of the bolts that you can reach, as there are 6 bolts, the are two or three you can access if you reach behind flex plate, unless it is bent too much. You can pry on plate a little, it is junk anyway, try not to damage anything else or yourself, go slow.

 

[cucvrus]

I hope you were able to get the torque converter unbolted from the flex plate by now. I have encountered this situation many times over the years that the engine was not able to be turned over. In your situation I would use a transmission jack or a floor jack on a level solid surface and just remove the transmission with the torque converter still attached to the flex plate. In the picture below I removed the oil pan of the engine and burnt the connecting rods off the crank shaft till I was able to get all the torque converter bolts by turning the flex plate 360*. That is not an option in your case and after the transmission is removed the bent flex plate will turn freely. Be careful and keep it level for a smooth dis engagement. A new seal will be needed. But if I had the transmission out I would go as far as taking it for an overhaul. Never hurts to do it right the first time. Good Luck and Be Safe.

 

[dependable]

If the engine is seized for some reason, most of our advice does not apply. I guess that should not be ruled out, but I can't think of how it would be caused by the original symptoms in this thread.

Burn connecting rods off crank? You give a lot of good advice here, but I can not picture the need to do that on any engine worth even a core charge.

 

[14ghz]

I havn't been unable to work on the truck since my last post, however I've been given some advice that it may not be the plate at all, but rather a spun bearing. which makes sense as the truck started squealing mid-drive and stalled out. It may be that the broken starter bolt was coincidental... can a flex plate just bend on it's own like that after it was running fine for 30 minutes? Unless of course a bolt came out and wedged itself up in the bell housing. I need to separate the engine from the trans to see what exactly is stuck. I'm going to try removing the glow plugs to reduce the compression and hopefully that lets me turn something enough to get the TQ bolts out. Thanks for all the suggestions here!

 

[dependable]

It is possible the crank shaft broke, it has happened on these trucks ,with 6.2s and low gearing, esp when the harmonic ballencer is going out and trying to drive at highway speeds, already at top of max RPMs.

If you have just spun bearing, logical solution in most cases is still to look for a good motor, either a good rebuild or a low miles take out that you are sure is and tests good.

You could also put in a reground crank w matched bearings, if you are sure the upper end is tight and you are into working on motors. go this route only if you have access to clean shop and some free time, if you have never done before. This is w spun bearing, if crank broke, some of the rods are likely bent, motor is just a core.

 

[cucvrus]

Yes I do know burning the rods from the crank shaft is labor intense. Probably not in the TM either. But I do what it takes to get the job done without breaking the bank and destroying good parts. The engine was worth about $10.. It was brought to me in this condition and I had it up and running with a replacement engine. It couldn't even power the wheel barrow when I was done with it. But I was able to keep the torque converter in place and not chew up any of the seals. I was the third person the worked on this HMMWV engine replacement. I was successful. The others were lets say NOT. I enjoy real challenges. I have a few engines and reassembled one that would do the job. The old one was NOT worth core. I scrap old engines for weight. Be Safe and keep in mind I have a few good HMMWV 6.2 engines in stock. You are not that far away. I do installations also if you are interested. Just not quick at the moment. I am on a major job at the moment.

 

[dependable]

.. can a flex plate just bend on it's own like that after it was running fine for 30 minutes? Unless of course a bolt came out and wedged itself up in the bell housing. I need to separate the engine from the trans to see what exactly is stuck.

If engine had a catastrophic failure, any number of things could have happened. Broken crank is just as common as spun bearing on these 6.2s. Dropping the oil pan is a good start in accessing engine condition, and a lot easier than getting torque converter off, it will also give you better access to back of flex plate.

If motor is lunched, and flex plate is really jammed, I suppose dropping the crank does make sense, you won't have to cut it out though, it is not rusty like above example.

 

[14ghz]

I brought it down to a shop, and their finding is that the motor is shot. the crank is completely seized. Could not get any movement at all.

So with that being so, where is a good place to find a replacement motor??

 

[frank8003]

Rich Guy says just buy a new one.

 

[antennaclimber]

Call John at Hillbilly Wizard.
Hillbilly Wizard