Used engine buying

Hey y'all first post here, getting ready to get my Jetta a new motor to swap in for the blown tdi in it that lost oil pressure on the freeway. The engine I'm interested in is said to have 76000 miles on it, and includes the transmission and turbo. It's from a 98 Jetta as well so it should be as painless as possible to swap in.

I'm wondering what are some things I should look over or check for on the replacement engine. Any tests or tools I should bring with to verify everything is legit? I should be able to perform and interpret any tests, as I'm not new to automotive, but don't have much diesel experience so I don't know what to look for in a used one.

Thanks in advance, have a great day everyone.

Take a close look at the odometer. If the word "Total" is not there, it means the car has gone past 300,000 where the reading resets to 0.

It doesn't seem reasonable that a car that age would have such low mileage.

If you can't hear it running, try to crank it over with a battery and do a compression test.

That that's not possible, turn the crank with a bar and socket 2 full revolutions and feel for resistance from compression 4 times.

In general, look over the exterior of the engine - does it look like it has been sitting in a muddy field? Are aluminum parts excessively corroded? Are engine openings plugged, or is it possible that water/moisture has got in? Are any of the engine parts or accessories broken indicating the engine has been mishandled?

Feel the turbo impeller for axial/radial play.

Thanks for the quick replies! I guess I should have mentioned it's already out of the car, but I agree that mileage is very low for that age, but I feel like if he was gonna lie about mileage he'd make it a bit more believable and say 120k or something like that. I'm gonna ask how he's got it stored right now.

Lots of people don't know about the behaviour of the Mk3 clusters - I would suspect ignorance over malicious intent.

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Although I'm not from Missouri, you'd really have to show me that this engine only has 76,000 on it!!

Is it still in the car? If so, look at the car… Does it look like it has only 76,000 on it? (worn out clutch and brake pedal pads, torn up seats on the driver side, etc. might be a sign of higher mileage then stated)

If you're buying it through one of the two companies that sells used motors… Both on the West Coast I believe, check out people's comments about them.

I would not pay a premium for this motor Unless you're absolutely certain it only has 76,000 on it. Caveat emptor!

The above suggestions by the other posters on how to check a motor that you cannot run and hear are quite good…

I bought a used B4 motor at a junkyard complete with the cluster having done the above investigations of turning it over several times and listening for compression. I paid so little for it that even if it was completely ruined internally I would not be out too much money. I powered up the cluster, turns out it had 279,000 on it. During teardown I found it had an extremely worn out water pump, and the previous owner had tried to avoid replacing it by using leak sealant...and made quite a mess of the water jacket passages.

Please keep us updated on how your motor purchase turns out...we are curious!

Regards,

Steve

Sorry, I didn't see it is already out of the car…

Well I'm starting to feel a bit more sceptical, because he's only asking $825 for motor trans turbo and down pipe. He said he plugged all open oil/water passageways and its stored indoors in a dry place and will send pics late tonight or tomorrow. Hopefully I'm just incredibly lucky. I'm thinking it's worth a shot for sure but that's why I'd like to write up a thorough list of things to inspect.
So far:
Timing belt intact/tight
compression and that it spins
Visual appearance
Metal in oil
Turbo play

Anything else? Seems to be more or less like checking a gas engine plus the turbo and minus spark.
One other thing I thought of, do I need a diesel or furthermore a tdi specific compression checker? I'm guessing yes since it's gonna go into the injector ports, but is there any special adapter I need for vw?

Well I can't post images yet I guess cus I'm new, but he sent me 18 images of a seemingly very clean original unadulterated ahu as well as a picture of a cluster in the car reading just under 75k. He said he bought it from an older lady and got rear ended shortly after. Keep your fingers crossed boys! I think I just lucked out super well!

Is the word "total" visible in the picture of the odometer?

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im also in WI, and if you are close enough, im willing to lend a hand/tools if you want the help with swapping

compression tester goes in the glowplug holes, not injector holes. I have one if you need it, just a harbor freight one but it works fine.

I'd love a hand! I'm in downtown Waukesha, WI which is about a half hour west on 94 from Milwaukee.

The word total was not there, but it was in the key off position so I don't think it would display either way, but from the pictures and my gut instinct I trust it's right, only one way to find out though and sometimes you just gotta trust people and hope for the best.

Get the VIN and run a carfax

That should tell you some helpful info

Well that's a huge letdown
What do you guys think then? Go check it out still or keep looking? Any recommendations on where to get a good used ahu? Honestly, I still haven't even called the yards around here yet so maybe I'll get lucky there.

He's saying that only gassers say total which sounds like a lie to me. But he did send a picture of his friend's cluster that says 420220 miles so idk. This is really bumming me out waiting for a vin to check on carfax.

Nope. Diesels say total as well. Owned a couple ahu cars, and one aaz. All had the total in the cluster.

As long as the engine and transmission are still together you can manage a compression check with some jumper cables and a battery. Higher mileage isn't a huge concern on its own. It also depends whether you plan to just drop the engine in or if you're going to actually rebuild it.

What I'd be more concerned about is the story from the seller... Now it's sounding less like ignorance and more like intent...

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Seller suggesting the cluster does not say 'total' for diesels is obfuscation. It would be extremely illogical for a manufacturer to specify a different cluster component when they didn't have to. And further that it would cost them more to do so, which is the reason VW has attempted to standardize components between gas and diesel cars over the years.

As a person who might buy a diesel engine I care less about the low mileage than I do about knowing how many miles were actually on the car. Knowing real true miles helps me decide if the price is reasonable and also what I'll be spending to refresh it before an install.

You'd be hard pressed to find a 1Z/AHU under 100k miles these days, most have crossed the border over into 250k miles already. My donor engine for the B3V project had 240k but the cylinder walls looked perfect and it's been running like a top with a cylinder head refresh. The spare AHU in the garage is a similar deal, it's got 196k miles verified by purchasing cluster too and since it was in an accident I'm confident that it would be good to go with a cylinder head refresh.

I'd do some looking around your area, try car-part.com for local JY's near you.

Steve

Thanks y'all, he talked to his friends and they verified the cluster saying total to be true. I passed on it and am gonna look around for one more week then decide if I'm gonna just sell the car and get a newer tdi. So far looking for a motor has just been a trail of dead ends and worry.

oracleglassarts said:

Thanks y'all, he talked to his friends and they verified the cluster saying total to be true. I passed on it and am gonna look around for one more week then decide if I'm gonna just sell the car and get a newer tdi. So far looking for a motor has just been a trail of dead ends and worry.

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I'd like to see a few pictures of the car this engine is needed for. That will tell me a lot about whether it's worth continuing the hunt for a new engine.

My 97 Jetta tdi came out of Wisconsin but started life in Alabama. Supposedly I'm the second owner according to VW. My car is relatively clean for having been in WI but it's not perfect by any means.

Steve A

I can't post pictures yet as I'm still new to the forum I'm assuming. But it's in decent shape, the outer rockers are the only places with any serious rust and I have a welder so that's whatever to me. There's also a very small hole in the drivers floor near the rocker, but again welderup!

Good news! Found a 98 Jetta tdi with 252k (with the total on the cluster) that runs and drives located 1 hour away. I'm tempted to just leave it and sell my current Jetta but the one I found is the ultra base model, manual windows and manual steering rack. On the other hand my Jetta has a vacuum leak on the locks, and only the moonroof and drivers window work, and the glovebox latch is broke.

I have a video somewhere of my A3 cluster going from "299999 Total" to "0".

Mix & match? I've upgraded my B4 with many options that weren't originally installed.

This may be a bit off topic but there has been much discussion about the word "total" being present if the odometer hasnt rolled past 300k.

My question: is this specific to the Jetta clusters? Are the B4 Passats the same way?

I have 96 Passat and when I bought the car it showed 63k miles, the word total is not there. I believe the car had 163k miles on it. I did have the car fax before buying it and if I remember correctly it showed the previous owner title of the car around 2014 and 140k miles. Which would make sense to have 160k miles on it when I bought it. Not sure why the cluster only shows 63k though, any thoughts?

The Passats didn't have the "total"

They had something far better - weak cluster capacitors, and a habit of dying if the car's voltage drops too low.

Odds are your cluster was replaced at some point, hence the mismatch between the actual odometer reading, and the one showing in the cluster.

oracleglassarts said:

Good news! Found a 98 Jetta tdi with 252k (with the total on the cluster) that runs and drives located 1 hour away. I'm tempted to just leave it and sell my current Jetta but the one I found is the ultra base model, manual windows and manual steering rack. On the other hand my Jetta has a vacuum leak on the locks, and only the moonroof and drivers window work, and the glovebox latch is broke.

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I can understand why you would want to keep your car, if it has more features that you would like to have. Some of those things can't be easily added later, for instance a sun roof is a bit of an endeavor, especially if you want a factory unit. Personally I don't use mine all that much in either car.

As for electric windows in a Mk3, you couldn't give them to me, they fail miserably and are expensive to repair. There should have been a recall on them but VW slithered their way out of that like they did for Mk3 heater cores.

Gloveboxes can be repaired, in fact I have three black Mk3 gloveboxes I'd sell if someone wanted one. All three have good working handles.

I am glad you found a whole car, be sure and take a look underneath so you get a clear picture of what the condition is, many mid-west Mk3 are headed to the junk yard by now, some Mk4 cars too. I've even seen B6 Passat cars at the JY!

If you have a photo hosting service that allows for third party links you can always post up pictures that way too.

PS - we never got a Mk3 without power steering, so if the seller is telling you it has manual steering then either they installed a manual rack or the PS is kaput.

Steve

Thanks Steve, I'll keep that in mind. It's got a mk1 scirocco steering wheel so someone may have done a steering rack swap otherwise power steering should be easy enough to swap in if the steering is tight for my liking.

Owner confirmed it's a swapped rack I'm so excited to go check this out and most likely buy it....Saturday can't come quickly enough.

oracleglassarts said:

Owner confirmed it's a swapped rack I'm so excited to go check this out and most likely buy it....Saturday can't come quickly enough.

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Check it out but be wary of what you see. I can find no good reason why anyone would swap a manual rack into a Mk3. Also, if the steering wheel is replaced with non air-bag that's an odd situation too.

Will be interested to hear what you find.

Steve