1PZ Leaky Injection Pump (1 Viewer)

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I was the unlucky soul that had to send mine to Dave Stedman as a core to get a rebuilt one back from Denso Japan (he dealt with them directly for me).

Long story short... local shop in town that does Denso pumps said it was not rebuildable which is why I went to Dave Stedman at Japan4x4.

I don't have a rebuilt pump but I do have a spare used one for a 1PZ I got from joekatana awhile back.

Also here is the link to the ad that was listing the rebuilt pumps (too bad he wasn't around when I needed one!): For Sale - Rebuilt pzj injection pumps - https://forum.ih8mud.com/threads/rebuilt-pzj-injection-pumps.1184477/
There's a place up in Richmond British Columbia that also does the pumps and injectors but be forewarned the cost of everything in the area is very expensive so I would probably try to avoid. Where is the other shop located at?
 
If you are asking me what shop I used. I used M&D Distributors to try to get my 1PZ IP rebuilt before I went to Dave Stedman. They have locations all over Texas and do a lot of IP rebuilding. The service advisor took me back to show me where they rebuild stuff. It was impressive to see their operation and they service a lot of IP brands.
 
Sometimes you can get away with a slightly oversized "O" ring if it's the shaft on top and the IP is otherwise ok.
 
Reviving this thread because I had hoped to post an update in here months ago with how I resolved this issue, but unfortunately it remains unresolved.

I located what seems to be a very reputable diesel pump/injector shop here locally (DPI in Houston, TX). They had exceptional reviews, are a Denso service center, and say their guy has been rebuilding Denso mechanical IPs for 30+ years. They seemed more than willing to take on the IP rebuild and answered all my questions and provided a fair quote, so I figured I got lucky and found a legit local shop to do the rebuild rather than sending the pump out.

The truck went to my mechanic (similarly, very well respected Cruiser specialist shop here in Houston) and they pulled the pump. I delivered the pump to DPI and they rebuilt it, then I delivered it back to the mechanic for reinstallation.

The mechanic reported back that since reinstalling the IP, the truck would run very rough and they needed time to further fine tune it. I read the FSM in enough detail to know that there are a lot of possible adjustments to be made on the pump, including its orientation, to get it dialed in, so I let them have the time to tweak it. Eventually they said that they had been making miniscule adjustments to the pump but still could not get the engine to run smoothly. They took it all apart again to confirm timing of the cam and crank, and after putting it all back together have not been able to even get the engine to even crank anymore. They confirmed that diesel is coming out of the injection ports and have been trying to get it tuned in for months now, but with no luck.

I talked again to the rebuild shop to explain the symptoms and they were very helpful offering advice and some things to check, but indicated that it sounds like a timing issue rather than an issue with the rebuild. I know they did bench test and tune the IP after the rebuild, and we've confirmed that the IP is delivering fuel, so I'm inclined to also suspect it's not a rebuild issue. They did offer to take another look at the IP.

Basically at this point my mechanic thinks it's an issue with the rebuild, and the rebuild shop thinks it's an issue with the re-installation of the pump. I'm kind of at a loss for what to do next here and although I understand how the system is supposed to function and have read the FSM sections on it, I'm not really knowledgeable enough on it myself to call out where issue might lie.

Three options I'm currently pondering as next steps:

1. Have the IP sent back to the rebuild shop and ask for them to re-do the bench test and ask to witness it. I didn't get any paperwork from their initial testing of the pump. The FSM gives lots of specs for how the pump should operate post-rebuild. This could uncover an issue but if it was never an issue with the rebuild all along, then it doesn't accomplish anything.
2. Send the truck to another local mechanic for a second opinion/to troubleshoot the installation of the pump or other possible issues with the fuel system. The mechanic that currently has the truck is the only one that's done work on my truck in the past other than me, so I don't have another trusted mechanic locally. I did speak to another shop that specializes in diesel fuel injection locally and they were willing to look at it, but I'm skeptical because they probably have never seen a Toyota diesel.
3. Ship the truck off to someone who's experienced with Toyota diesels. I've heard of some references here on Mud. Obviously this is a costly option.

So... any advice?
 
have been trying to get it tuned in for months now,
They don't have a clue. It would take someone an hour or less to decide if it was a pump rebuild issue or if it was their own issue. Your mechanic is way out of his depth, it shouldn't have taken him months to decide its a rebuild problem. In all honesty, I doubt he really knows.
Its quite likely they have altered the settings on the pump and this is part of the problem.
I would make sure nothing has been damaged in regards to the timing belt etc. These are interference engines. Once it leaves the shop they will deny any internal damage.

I would give the original pump rebuilder a chance to show they did it properly. I would not bring a 3rd party in to touch the pump or anything else, except as a last resort.

Any qualified diesel person should be able to repair almost any diesel with a workshop manual. Many of the guys on MUD, including myself ,can do this with little or no training.
Toyota diesel engines like the PZ /HZ are the same as dozens of others, they have a rotary pump and are indirect injected. They are probably the easiest multi cylinder diesels to work on.
Look for shops who can do the rebuild and installation where possible (not always easy, I know)
 
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@roscoFJ73 thanks for the perspective. It seems a bit contradictory how you say anybody should be able to repair one of these diesels with the service manual, however a professional mechanic couldn’t figure it out. That being said they are not diesel people and are used to working on petrol cruisers.

What would I want to inspect for damage other than the belt itself?
 
That being said they are not diesel people and are used to working on petrol cruisers.

That's your problem. Petrol mechanics in Australia wont usually look at a diesel engine beyond an oil and filter change. They sometimes fix them, but they are slow and don't always have the exact tool , workshop manual etc
As to removing and fitting diesel fuel pumps, I did mine for the first time with no help, just the manual. And I put all the timing gears and hardware on in that area. I just worked through it methodically double/triple checking as I went.
It started and ran perfect the first time.


What would I want to inspect for damage other than the belt itself?
Its an interference engine. That means if the timing belt is out by a few teeth, a piston will come up and hit valves that are still open. If that happens it will leave dents or even holes in the piston, or bend valves. I'm not suggesting that has happened, but if it has, and you remove it from their workshop, you are sunk.
I prefer to give people the worst scenario and if it doesn't happen , all good. I dont believe in sugar coating things which can end up costing big dollar$
Its hard to blame the pump rebuilder when he says he bench tested it. And then it ran, but needed tuning and now it doesn't run at all.
 
I had a local shop reseal a 2LT ip a few months ago and they are a full on diesel shop but yet they succeeded to make a mess of it with a cruiser that had absolutely no power after rebuild and was running rough , after reading up online and speaking to a few people with a ton of experience on this particular engine it all pointed out that they missed a few splines with the trottle linkage , when I suggested this to them they where sure that they where not at fault and didn't make any mistakes and kept on adjusting everything else , long story short in the end they adjusted the trottle linkage and it ran like before and I got the bill for their screw up ! Reach out to a few people in the community that are familiar with replacing /adjusting pumps and take it from there.

BTW if you need pics for reference from any factory settings I have a 1PZ sitting here at the shop and even if there should be an issue with that IP I have a spare .

Good luck sorting this out
 
Thanks Joe, good to know i have a fallback if needed.

Working on finding a good local diesel mechanic to take it on and I plan to have that be my next step.
 

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