Removing, rebuilding, reinstalling Hydraulic Head

[kennys@wi.rr.com]

Yep. I think I still have a few sets if you need the,.

 

[RAYZER]

Here's one.
Had the HH off of the lds IP that I installed on my Ldt.
The HH orings from the ldt HH
Looked good,they were not that old so I used them, they functioned properly.
After many miles of operation an external fuel leak developed, it took me awhile to track it down, turned out the leak was coming from the top HH oring (crankcase oil level always fine).
Re snugged the 4 HH nuts.
Leak fixed!

 

[NITEFARMER]

Thanks Kenny for the great post. I have the same problem and hopefully I will get to work on it this weekend.

 

[turbett1]

I just joined this forum. I am new to MV's. I am working on an m35a2 at work we have a bunch of them I work on a military range. we have many extra parts and engines for these trucks. I am currently working on a water tanker m35a2 that stopped running a few years ago after having crappy biodeisel put in it. It will start on ether. The fuel tank has been emptied and fresh deisel put in the lift pump has been cleaned and it working. I am getting fresh deisel at the primary and secondary filters and I cracked the high pressure lines at the injectors and I am getting fresh low pressure fuel drips from them while cranking the engine. I suspected injector were gummed so I removed and cleaned them, in all 6 the injector valves were basically glued into the injector nozzles from the crappy fuel. I was able to clean and reinstall. still no fire so I started checking the engine stop fuel lever I was glued as well in the same way so I cleaned and it rotates freely I reinstalled into the HH but it still doesn't rotate easily the push rod from the governor moves freely. So the only thing I can think is that the HH is glued up as well I am in the process of removing it I've got everything unhooked and all that is left is to line up the red/scored tooth and the 4 retaining nuts and lift up. when I pulled the center bolt on top of the HH I got very little fuel even whIke cranking so I think the plunger is glued stuck in the up position. I'm going to try and free everything up. Am I on the right track? There are several other truck we have at work that have had the same fuel run in them and stopped running so if I can figure out how to clean these out I will be able to put numerous trucks back in commission.

 

[gimpyrobb]

Welcome to the site. You need to update your location from the U.S. to a state.

Yes you are on the right track, I bet the button retainer on the bottom of the hydraulic head has let go. I have some new ones if you decide you need/want one.

 

[kennys@wi.rr.com]

Just turning the power switch on there will be fuel flow, as long as the in tank pump is working. The fuel will even flow out the injector lines under low pressure. I would check the entire fuel system from the intank pump through the primary filter and then through the secondaries. You may have a crushed copper fuel line or a plugged filter. Pull the center plug on the HH and put a dowel in there and have someone turn the motor over and make sure the plunger is going up and down. Start there and then report back. If needed PM me and I can call you and walk you through it.

 

[Another Ahab]

I just joined this forum. I am new to MV's. There are several other truck we have at work that have had the same fuel run in them and stopped running so if I can figure out how to clean these out I will be able to put numerous trucks back in commission.

Welcome from Virginia.

Sounds like you're on your way to the promised land; good luck with that.

 

[turbett1]

Ok. So I got the HH and the button and clip had fallen off, the clip is broken. This happening caused the plunger to be pushed up too high and it stuck in the up position the entire HH was also gummed up with the crappy fuel so that didn't help. I pulled the plunger out, cleaned, oiled and lapped it a bit with a handheld drill on slow speed it now moves smoothly as it should in the HH. I also broke the shear plate that fits inside the gear as kennys@wi.rr.com did when driving the plunger out. I have an old rusted IP in our yard im going to pull apart to try and get the parts I need. BTW the button was mangled and the clip has 2 little missing prongs I could only find 1 in the IP no idea where the other one is hopefully in the oil pan, do you think I am ok to reassemble once I replace the shear plate, button, and clip? any other suggestions?

 

[turbett1]

Ok. So I pulled off the HH and the button was mangled and the clip was broke. found a surprisingly clean HH on a parts engine we have and installed it instead of trying to rebuild the seized one. Cranked for a while then I bled the return line, gave her a shot of ether and she purrs like a kitten now. thanks for this thread and everyones moral support haha! I have learned a lot about M35's diagnosing this truck and I am sure the knowledge will come in handy in the future. This is an awesome forum and I want to buy a personal M35 or 5Ton now I never realized how BADA** you can make these things until I started searching this forum.

 

[Another Ahab]

I have learned a lot about M35's diagnosing this truck and I am sure the knowledge will come in handy in the future. This is an awesome forum and I want to buy a personal M35 or 5Ton now I never realized how BADA** you can make these things until I started searching this forum.

You can thank patracy for that:

- He is the Founder and "Godfather" of the site

We all owe it all to him (or somebody please correct me if I am wrong). He is the genius behind the curtain.

 

[gimpyrobb]

You can thank patracy for that:

- He is the Founder and "Godfather" of the site

We all owe it all to him (or somebody please correct me if I am wrong). He is the genius behind the curtain.

Yup, wrong there.

Chris started the site and there have been plenty before Patracy. While he is currently at the reigns, I doubt he should get all the credit. As Drew once said, he just pushes buttons and gets bananas.

 

[Another Ahab]

We all owe it all to him (or somebody please correct me if I am wrong). He is the genius behind the curtain.

Yup, wrong there.

Chris started the site and there have been plenty before Patracy. While he is currently at the reigns, I doubt he should get all the credit. As Drew once said, he just pushes buttons and gets bananas.

Wasn't sure at all, but wanted to give credit where credit is due:

- Figured that somebody would call me to the carpet, and lay it all out.

Thanks, Gimp.

 

[gimpyrobb]

No BIG deal, just wanted to point out Chris and Mangus did a lot. Doghead did a lot till Patracy came along. Lots of input from the general population too.

 

[kennys@wi.rr.com]

I'd like to give credit where it is due as well. Had it not been for Gimp I would not have been able to do this repair and start this thread.

 

[gimpyrobb]

I'd like to give credit where it is due as well. Had it not been for Gimp I would not have been able to do this repair and start this thread.

And I got my info from other members here! Its a hellova community!

 

[oddshot]

I pulled the HH from the IP and as I was lifting it out of the IP, the bottom bits came apart. It seems that the O-ring had been installed so that it pinched under the tin cover looking thing. That appears to be why I've been making oil lately.

Now I have a part that I can't figure out how it installs.

The diagrams in TM 9-2910-226-34 (Page 3-62 &63) describe this part as the plunger sleeve.

I see that this part has a slot machined into it ... and I see that the slot should be facing the window.

But there is a small, shallow hole that has been drilled into this part. This is NOT a through hole.

I can find no reference to this hole in the TM. I've measured this thing just about every way I can think of and I don't think it makes a difference. I've searched for other manuals that may describe this part, but have been unable to find anything.

My question ... does the hole go up or down? Or does it matter at all?

Thanks

 

[kennys@wi.rr.com]

I don't think anyone has ever been able to answer that hole question. the main thing is the slot points to the outside of the HH. Your shutoff rod has a small tab on it that fits into that slot and that's how it moves up and down to shut the fuel off.

 

[Another Ahab]

I can find no reference to his hole in the TM. I've measured this thing just about every way I can think of and I don't think it makes a difference. I've searched for other manuals that may describe this part, but have been unable to find anything.

My question ... does the hole go up or down? Or does it matter at all?

Thanks

I don't think anyone has ever been able to answer that hole question. the main thing is the slot points to the outside of the HH. Your shutoff rod has a small tab on it that fits into that slot and that's how it moves up and down to shut the fuel off.

It's not written in any particular manual, but in the whole wide world I believe the record shows that there is only one hole that really matters...

 

[rccollin]

Man I am balls deep into removing my hh to replace the o rings and I CANNOT find the red tooth, or any tooth that looks any different. Any help?

 

[Floridianson]

Are you using the jackshaft and turning the motor real slow so you can see every tooth. It's there but the red might not be but. It will still have the small line scribed in the tip of the tooth. If all else fails just line up the timing marks on the HB and the advance unit window and the red or scribed tooth will be one tooth to the rear. Then you need to rotate the motor back just a bit to get the HH scribe tooth on it's pointer for removal. The HB and advance unit timing marks then will be just off there marks.