Welcome to my 1HDT rebuild nightmare.

[Magic Spool Bus]

1st thing my CAN friends did when they bought an HD-J81, was immediately upgrade the bottom end bearings. I don't know if they can contribute to crankshaft failure, though.

Those were done at 97k/km

 

[roscoFJ73]

I can’t even google search and find who west coast cruiser is...

I think his name was Mike, Im not sure if he still posts on MUD.

 

[roscoFJ73]

I have never heard of a 1HD T (or 1HZ) crank snapping before. We used a HDJ80 to tow an excavator in the 90s with mulitiple drivers often driven hard . We even towed it at a 100mph once. And it was still going ok at 300000klms, never had the beb's done, although it had just started to tick last time I saw it. They are a tough engine.

 

[Loober]

I think his name was Mike, Im not sure if he still posts on MUD.

I know Michael personally, he is a really cool guy and is a hard core land cruiser collector, he probably still has the west coast cruiser name but he does not provide service to others anymore. I went through a similar scenario with my 1HZ, not a snapped crank but a blown engine, and went down the road of pricing everything out for a rebuild, and it quickly became apparent how expensive that is, that was just parts/machining, I was planning to do the assembling myself. A new crank alone would probably run you 1-2k, plus all the rebuild parts, machining, proper tools, etc. I ended up finding a used 1HDFT for not much more then the rebuild, very happy with that decision, and I ended up parting out the good parts of the 1HZ for half the cost of the new motor. I've seen a few 1HDT in the classifieds lately, so they are out there, if I were you I would seriously consider that route. I am in SD as well, and have a good bit of experience with these motors, let me know if I can be of help.

 

[Magic Spool Bus]

I know Michael personally, he is a really cool guy and is a hard core land cruiser collector, he probably still has the west coast cruiser name but he does not provide service to others anymore. I went through a similar scenario with my 1HZ, not a snapped crank but a blown engine, and went down the road of pricing everything out for a rebuild, and it quickly became apparent how expensive that is, that was just parts/machining, I was planning to do the assembling myself. A new crank alone would probably run you 1-2k, plus all the rebuild parts, machining, proper tools, etc. I ended up finding a used 1HDFT for not much more then the rebuild, very happy with that decision, and I ended up parting out the good parts of the 1HZ for half the cost of the new motor. I've seen a few 1HDT in the classifieds lately, so they are out there, if I were you I would seriously consider that route. I am in SD as well, and have a good bit of experience with these motors, let me know if I can be of help.

Sent you a PM

 

[Sonofaskipper]

I have never heard of a 1HD T (or 1HZ) crank snapping before. We used a HDJ80 to tow an excavator in the 90s with mulitiple drivers often driven hard . We even towed it at a 100mph once. And it was still going ok at 300000klms, never had the beb's done, although it had just started to tick last time I saw it. They are a tough engine.

Rosco,

I’ve heard much about the tell tale impending BEB failure tick. How does it differentiate itself from the “normal” tick these engines seem to produce?

 

[SHREDwagon]

Front / rear Main seals would be leaking ALOT well before crank failure. There must be some correlation with recent work done - a machinist will be able to tell.

 

[roscoFJ73]

Rosco,

I’ve heard much about the tell tale impending BEB failure tick. How does it differentiate itself from the “normal” tick these engines seem to produce?

From my experience the BEB tick is rythmic, where as the others come and go and dont necessarily conform to rpms. But I can only relate to the tick I have had on 1HZ's. Others may have different tales.

 

[roscoFJ73]

I havent owned or driven anything with a broken crank, but it seems the crank would have to be shock loaded to snap. I guess if it was running hot on a main bearing it could create a weak spot, but you would have low oil pressure.

 

[animas]

1HDT with 105,000km. Went in for a transmission rebuild and coming out needing a engine rebuild FML.

A little back story. About 6 months ago I had my ACSD sheer off inside the pump and do some significant damage to the pump and a few injectors. It was only running on a few cylinders. Skipping, smoking and shutting off all the way to the injection shop. After it was buttoned back up with rebuilt pump and injectors the truck has ran amazing for about 5,000km.

NEW ISSUE: my clutch hydraulics gave out. Towed it to shop to have a new clutch installed and the H151 rebuilt with new synchros, new slave and rebuilt master cylinder. Before I towed it to the shop I noticed the crank pulley wobbling just a very small amount. Figured it was the harmonic balancer going bad so ordered a new one. Go to pickup the truck after it’s trans overhaul and hear a noticeably loud knocking coming from “somewhere”. The shop thought it was the new HD clutch. Take it for a quick spin still has good power and runs fine, no smoke, overall not bad other than the unknown chatter. Popped the hood to see that the crank pulley was noticeably wobbling even more and the sound appears to be coming from the balancer and oil pan area. Once the harmonic balancer was pulled it was very apparent the crankshaft has an abundant amount of end float and up and down movement just by hand.

Obviously so far I don’t know if the crank has snapped or if the thrust and main bearings are shot. The BEBs were done on the truck at 97,000km. Plans are to pull the engine and rebuild and replace whatever is necessary.

What I’m really here for and hoping some of the experts here can weigh in on is why is this somewhat a common issue on these diesels. I’m worried that even after a complete engine overhaul. This same scenario will play out again and never know exactly why. My only best guess some damage was done when the injection pump took a poop.



Thanks for any help and insight.

Had that happen to me but on a gas pick-up. The clutch was rebuilt before I got the truck and it was adjusted badly so the hydraulic slave cylinder kept pressure on the clutch throw-out lever. That end-loaded the crank shaft until the thrust bearing went. Before I knew it I'd lost oil pressure. If the clutch master cylinder does not retract all the way when you release the clutch the hydraulic pressure will not be released from the slave and the slave will keep pressure on the clutch. If you check down by the bell housing when you're not stepping on the clutch there should be some play between the slave and the throw-out lever.

 

[Magic Spool Bus]

Had that happen to me but on a gas pick-up. The clutch was rebuilt before I got the truck and it was adjusted badly so the hydraulic slave cylinder kept pressure on the clutch throw-out lever. That end-loaded the crank shaft until the thrust bearing went. Before I knew it I'd lost oil pressure. If the clutch master cylinder does not retract all the way when you release the clutch the hydraulic pressure will not be released from the slave and the slave will keep pressure on the clutch. If you check down by the bell housing when you're not stepping on the clutch there should be some play between the slave and the throw-out lever.

This is very interesting... when my truck went in to the shop originally it was because my clutch was having issues and I could feel through the clutch when changing gears something rotational scuffing around. I could feel it in the pedal and through the gear stick and it was audible. Almost like the clutch not fully disengaging. My hydraulics had just went out while driving on the free way the very next day. Pedal just went to floor and had no pressure and I couldn’t shift gears. Got the truck home looking for leaks and couldn’t find anything at all. I also noticed a very slight wobble in my harmonic balancer while trying to find the issue. I just figured it was 25 years old and delaminating (not a big deal I’ll buy a new one). I was going overseas so I had it towed to a shop to do the work while I was gone. When it arrived at there shop the hydraulics were working and the clutch was operating fine.

Decided to pull the transmission anyways to explore deeper. Clutch was fine throw out was in tact and nothing seemed wrong. I just said screw it let’s put some new synchros in while the box is out and I have some spare cash. 2nd and 3rd gear had always been super picky anyways so might be worth it. Still not happy with that rebuild but that’s another issue.

Finally got the call from the shop to pick up the truck as it was ready. When I arrive to test drive it they inform me they think my new NPC 800nm clutch was heavy duty and making a racket. Whatever let’s take it for a spin I haven’t drove this thing in months. Upon start up there was a rhythmic knock. Drove it about 10 miles and said nah somethings wrong I can feel the knocking through the clutch pedal and it’s just not right (felt nearly the same as the originally issue). Popped the hood and the harmonic balancer was making the noise and noticeably wobbling a lot more.

One characteristic that I noticed that changed with the new clutch and new slave cylinder (the slave looks noticeably larger) is that the clutch grabs as soon as you crack the pedal from the floor. It’s actually another issue I will need to sort out once the engine gets back in. NPC said something about a smaller bore slave for there clutches. A few others have had this issue with there clutches as well.

I wonder if my clutch had anything to do with this. My original clutch acted fine and started grabbing about midway through pedal travel.

I should state the the new clutch was only driven about 20 miles after it was apparent something was awe fully wrong with the crankshaft so it’s obviously not the issue. It’s just odd that the clutch hydraulics went out right before I discovered the harmonic balancer wobble which ended up being a snapped crank.

 

[animas]

This is very interesting... when my truck went in to the shop originally it was because my clutch was having issues and I could feel through the clutch when changing gears something rotational scuffing around. I could feel it in the pedal and through the gear stick and it was audible. Almost like the clutch not fully disengaging. My hydraulics had just went out while driving on the free way the very next day. Pedal just went to floor and had no pressure and I couldn’t shift gears. Got the truck home looking for leaks and couldn’t find anything at all. I also noticed a very slight wobble in my harmonic balancer while trying to find the issue. I just figured it was 25 years old and delaminating (not a big deal I’ll buy a new one). I was going overseas so I had it towed to a shop to do the work while I was gone. When it arrived at there shop the hydraulics were working and the clutch was operating fine.

Decided to pull the transmission anyways to explore deeper. Clutch was fine throw out was in tact and nothing seemed wrong. I just said screw it let’s put some new synchros in while the box is out and I have some spare cash. 2nd and 3rd gear had always been super picky anyways so might be worth it. Still not happy with that rebuild but that’s another issue.

Finally got the call from the shop to pick up the truck as it was ready. When I arrive to test drive it they inform me they think my new NPC 800nm clutch was heavy duty and making a racket. Whatever let’s take it for a spin I haven’t drove this thing in months. Upon start up there was a rhythmic knock. Drove it about 10 miles and said nah somethings wrong I can feel the knocking through the clutch pedal and it’s just not right (felt nearly the same as the originally issue). Popped the hood and the harmonic balancer was making the noise and noticeably wobbling a lot more.

One characteristic that I noticed that changed with the new clutch and new slave cylinder (the slave looks noticeably larger) is that the clutch grabs as soon as you crack the pedal from the floor. It’s actually another issue I will need to sort out once the engine gets back in. NPC said something about a smaller bore slave for there clutches. A few others have had this issue with there clutches as well.

I wonder if my clutch had anything to do with this. My original clutch acted fine and started grabbing about midway through pedal travel.

if your clutch releases as soon as you crack the pedal it's set-up way too tight and that will end-load the crank. Check your clutch pedal. when its all the way back the piston should have a little play. it should feel loose. At the end of the master piston there is a spring with a small valve attached. when you release the piston almost all the way that valve opens and allows the slave cylinder to depressurize and disengage from the throw-out lever. Otherwise it can build-up pressure and maintain pressure on the throw-out bearing. Also if all this is in order check that there is play between the slave cylinder and the throw-out lever. hope that helps you.

 

[animas]

if your clutch releases as soon as you crack the pedal it's set-up way too tight and that will end-load the crank. Check your clutch pedal. when its all the way back the piston should have a little play. it should feel loose. At the end of the master piston there is a spring with a small valve attached. when you release the piston almost all the way that valve opens and allows the slave cylinder to depressurize and disengage from the throw-out lever. Otherwise it can build-up pressure and maintain pressure on the throw-out bearing. Also if all this is in order check that there is play between the slave cylinder and the throw-out lever. hope that helps you.

I'm so anal about my thrust bearing that when i'm at a long light I throw the truck out of gear and release the clutch. When I sold my old 3b with 650,000 km. it still had .009 end play in the crank.

 

[Magic Spool Bus]

The new OEM short block will be on its way very soon. New G Turbo waiting to go on as well. Old turbo is leaking quite a bit of oil.

May rebuild the stock CT26 just to run in the new short block then bolt on the G Turbo. Any thoughts on that? I read conflicting info about using a new turbo while breaking in a new engine.

 

[mudgudgeon]

Don't mess about with the old turbo.

Let it bed in for 500km with mild load, then run it in hard, don't baby it. I see absolutely no reason not to run g-turbo from the get go

 

[Magic Spool Bus]

Well Dave Stedman from Japan4x4 pulled through with a new short block and LOTS of other parts from japan. It cost more for the Port of LA to receive and release it to me from the cargo ship than it actually cost to ship it. Who would have thought I hope to have it installed in the truck by the end of the month.

 

[lelandEOD]

Dave is the man! Congrats!

 

[veiloctane]

keep posting im excited to see your build thread!

 

[Jroc561]

Nothing like a fresh shortblock, looks great. California custom fees are no joke

 

[Magic Spool Bus]

Well it’s finally assembled and in my garage. Just sorting out a few nut and bolt issues before I throw it in.
Any advice on priming they engine oil pump and turbo before actually starting the engine?