1PZ Leaky Injection Pump (1 Viewer)

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Joined
Apr 18, 2018
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Location
Beaver, PA
Went into the garage the other day after I had driven the truck around town a bit and thought it smelled like diesel. A quick look under the truck revealed some fluid was dripping on the front axle housing. Further investigation under the hood and it seems to be diesel dripping from the injection pump. This only happens when running and I haven't noticed any performance issues. It's not leaking terribly - maybe a drip or two per minute. It's hard to tell where it is leaking from - the whole bottom portion of the pump seems wet and I just get the occasional drip off the bottom. This leads me to believe though that it's probably not just a fuel line but one of the seals of the pump itself.

I've read some of the horror stories on here regarding the rarity of these pumps which are unique to the 1PZ. I guess I'm just looking for input from anybody who has dealt with this. Is there anything that could be an easy fix to check first? Are there seal kits available such that a local shop would be able to get the parts to rebuild it? I remember reading about someone on here needing to send theirs to Japan for rebuild and some absurd costs associated with these pumps.

Finally, I recall someone on the classifieds selling several rebuilt PZ injection pumps several months ago for like $650 or so. I remember it because I strongly considered buying one for a spare but figured it was unlikely to happen to me... figures. Anyway, I couldn't find that post... Are you still out there???


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I would google the part number on the side of the pump and look for a seal kit. If they are available just have it shipped out to be rebuilt.
 
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/
 
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Guys, this comes up time and time again. This is just the pump seals failing. It doesn't mean the pump is worn out or necessarily needs rebuild. It happens to tons of the JDM diesel imports with Denso rotary pumps.

Pump seal kit for these is not hard to get, and costs about $50. Replacing the seals is not that hard. I'm a DIY mechanic, and I'd successfully re-sealed a couple of these pumps now with no problems.

It's the labor to remove/reinstall the pump that is most significant. Again, if you're a DIY'er, it's not a big deal. If you have to pay someone, it will get expensive quickly though.
 
I'm going to say that every pump at this age (25+ years old) most likely needs a full overhaul. Toyota/Denso/Bosch specifications generally call for 100K miles or 10 year overhauls of the IP.
 
I am also going to say that the reseal kit looks harder than removing/installing the IP if you are using all the seals. I have a reseal kit somewhere in my garage and tossed that idea real quickly as it was outside of comfort zone.

If the leak can be narrowed down to one seal then even the entire kit at $50 bucks is well worth it for just the seal that is needed.

My leak was related to the ACSD device failing which the OP of this thread does not seem to have. When the ACSD goes bad, it can take the whole pump down along with it.
 
I agree with what everyone has posted, but would add, I would call a reputable diesel shop in the Houston area first prior to ordering a seal kit. I brought my seal kit to the repair shop, and they looked at me like I was from another planet. They said they had all of the seals required. This rebuild will probably cost between $500-1000 dollars taking it to a shop that specializes in Injection Pumps. You can most likely save $50 bucks in seals, since they will probably have the parts / seals in stock and put that $50 bucks towards a new timing belt, coolant hoses, and accessory belts, which the diesel shop will not have in stock. The phone call is cheaper than $50 kit, plus the time to get it, unless you plan on re-building it yourself.
 
Thanks all for your input. I know this is a re-occurring question and I've read what's already out there, just trying to get a better feel for what my options are and see if I might get lucky with somebody who could help out haha.

I've seen some success stories about people replacing a single seal themselves and that solving the issue, but as was also pointed out, given the age of the pump it is probably due for an overhaul and I'd rather take the time and money to do it correctly now then not have to worry about it for another decade or two.

I'm inclined toward DIY but know my limits. From what I'm seeing, a full pump rebuild seems clearly outside my ability. Right now I'm thinking my best option is likely to buy one of the rebuilt pumps from crawlin cruiser, linked above. Seems equal price or cheaper than re-building mine but the part I'm unsure about is that those seem to have the ACSD device (is this the same as what I'm hearing called "High Altitude Compensator?") whereas my current pump does not. I'm not sure if it will be able to be a direct replacement - any insights? I'll need to pull the nameplate info from my current pump when I get home and do some research.

If this doesn't work, I'm thinking my next course of action should probably be to talk to some local diesel shops to evaluate local rebuild options.
 
You can't really beat $650 for a rebuilt IP for your 1PZ. I think that is the best route.

"High Altitude Compensater" isn't the same thing as the ACSD. The ones that crawlin cruiser are selling don't have the ACSD in any of the pics.
 
I would suggest having it bench tested when out, but not just blindly rebuilt. When these pumps start wearing out, it's really quite obvious. They get noisy, hard starting even when warm, smokey, low power, etc. Most don't need it until around 300,000km or more.

A lot of people pay a lot of money to have these pumps 'rebuilt' without understanding what is actually being done. Make sure to ask for details if this is being done. To me, a rebuild would include a new pump plunger and head, and probably cam plate. Along with all seals, springs, etc. I suspect a lot of people are paying for 'rebuild' but getting new seals and re-calibration only.
 
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Clean the pump down with a degreaser and wipe it dry. Then start the engine and watch for leaks, even if you have to lay under there with a torch. You cant make a decision until you know approx where it is coming from.
Most of the pump parts will be the same as a 1HZ. Denso keep parts on hand long after Toyota refuse to stock them.
 
but the part I'm unsure about is that those seem to have the ACSD device
Most 1HZ and 1PZ dont have the ACSD. Its an emissions device and not all markets have them.

Look for a Denso/Bosch fuel injection specialist. These pumps are fundamentally the same as VW Bosch rotary pumps .
 
Why is there fear in your eyes? You do know only americans call a torch a "flashlight" ?
 
Why is there fear in your eyes? You do know only americans call a torch a "flashlight" ?

lol...it was a new Australian-English word for me.

Had a family relative tell me back in the 90s, he visited Australia and he was soon tired of them putting beets on his burgers so he finally told them to “cut the beets”. They brought his burger out with chopped beets on top of the meat.
 
I'm going to say that every pump at this age (25+ years old) most likely needs a full overhaul. Toyota/Denso/Bosch specifications generally call for 100K miles or 10 year overhauls of the IP.

Agree.

I have had the 1PZ pump done no probs locally for about $600.

Cheers
 
lol...it was a new Australian-English word for me.

Had a family relative tell me back in the 90s, he visited Australia and he was soon tired of them putting beets on his burgers so he finally told them to “cut the beets”. They brought his burger out with chopped beets on top of the meat.
I think that would be that restaurant only. A lot of aussie don't like beetroot. I do, but not from a tin.
 
I think that would be that restaurant only. A lot of aussie don't like beetroot. I do, but not from a tin.

Point was is that "Yanks" usually say "cut the...." as to say to eliminate or leave off something....especially with food orders. Not to chop it up.

At least that is how the story was told to me by my uncle.
 

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