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Recently purchased car (not in person- was told "all GPs were replaced" yet there continued to be a code for #2; I suspected it was the wiring harness as it had encountered a severe case of Black Death- dealer mitigated). While doing a cursory initial cleaning up of the engine/bay I nudged the #2 GP top/connector and found it to be loose. Pulled up on the wire/cap and this is what I found:
Here's a shot of the hole:
Note sure the actual state of the threads. Pictures always tend to make them look worse than what they really are.
Is this salvageable? Could the nifty "KL-0369-30 K" tool work on this?
I'm NOT wanting to pull a head. (so I say)
I'd bought a parts car (with, I believe, but yet to fully assess, a good engine and trans) as an insurance policy. Figured odds of having two bad engines would be pretty low.
Last edited by RA030523; Dec 27, 2022 at 08:15 PM.
Reason: add more clarity
I tried running taps but, while going in and seemingly running down OK, I am not confident that the threads are good. I tried threading a GP threaded section and it doesn't want to engage: too sloppy?
Seems that I might need to do a full-on thread repair using something like a Time-Sert. What I'm currently thinking is that I'd want to do this NOW and leave what's down below, down below. This would give me proper threads for installing a replacement GP when the time comes*.
* I'd just drive the car and hope the old guts came out on their own: got no idea what's down there. When/if that happens then I'd just thread in the new GP and be done. Assumes, that is, that the actual seat is OK.
Question: Does that top shoulder area matter? Can I take a reamer and clean that up a bit (just making sure that there's no extra material hanging out into the hole area)?
sand8, it's the resultant hole size of the repair kit(s) that was the issue/unknown. I got that info from Dennis at Wise Auto Tools: 13/32". The monkey that hammered on this thing ruined it beyond repair.
Some of my difficulties in assessing this is that I wasn't quite clear how GPs actually thread and sit in the cavity in the head. Looking at this picture of the just the core of the GP thread body it is obvious that this is REALLY bad (I set this in there- this isn't broken off/stuck in there [refer to my other pics]):
I talked to my diesel truck mechanic guru (high performance guy, one of the best around these parts) and he said it looks like someone tried to peen the GP into the head. I think he's right. Someone tried to bury the crime...
I took out an "insurance policy" when I bought this car. I had picked up a parts car at the same time I bought this car. Will be doing an engine+trans swap: have many reasons to do this; the GP issue "helped" push that decision. In the end things will end up being really clean.
Yes, it seem the only way to repair that is to take the head off for filling and drill/tap new hole. sad to see but hope you can get it right once you swap the engine.
I'm Franko6 usually on the TDIClub, but following this glow plug problem. I suppose you could try to install a TimeSert, but the real issue isn't that the threads are all buggered up. It's that the seat where the glow plug SEALS is GONE!
What it appears to me is that some FOD from inside the engine must have struck the glow plug, maybe so hard it knocked the GP out. Not positive about the FOD, but this is glow plug carnage. I personally would condemn the head, as there is no way to resolve the seat issue. The only cure I could recommend (and it's really just how to 'pick your battle'), is to put maybe a 12mm fine thread tap into the hole and then put something like a oil plug into the hole and tighten it up. At very least, the engine will now run. You will get a 0380 OBD code, for glow plugs, but your car will move again.
Just expecting a TimeSert to fix this is only pouring more money down a rathole. The TimeSert isn't particularly cheap and the GP will not seal on the threads. It seals at the chamfer above the glow plug tip... about a 55 degree angle. But it doesn't matter if you remove the head or not. Getting this repaired, and I've fixed a few tons of them... is not going to happen.
Recruiting some big guns to this site! Many thanks, Frank, for signing up and posting here. [I'm a long-time TDIclub member - "UhOh" and am quite familiar with Frank's stellar reputation.]
I have pulled the engine and trans from my parts car and am doing some prep work on it now. Have someone interested in this munged-up head engine (trying to figure what it's worth - it's a great running engine).
Don't want to burst your bubble, but the only thing you might do with that head is plug the glow plug hole, as I explained earlier and hope somebody from the Southern States who doesn't need glow plug to get the engine to start or just break it down to use for parts.
If you plug it, you can defeat the CEL you are going to get with a 90-100W power resistor that can take about 15 amps, and shunt it to ground. That will emulate the glow plug you don't have.
Personally, anyone that would claim that the glow plugs were working a *^#&$ liar. That CYLINDER couldn't have been working, at least not well.
Good luck with the rest of it. Hopefully, you didn't buy a 'hangar queen'.[
QUOTE=DieselBound;8705119]Recruiting some big guns to this site! Many thanks, Frank, for signing up and posting here. [I'm a long-time TDIclub member - "UhOh" and am quite familiar with Frank's stellar reputation.]
I have pulled the engine and trans from my parts car and am doing some prep work on it now. Have someone interested in this munged-up head engine (trying to figure what it's worth - it's a great running engine).[/QUOTE]
Frank, I'm putting this fully operational engine (and trans) in (I was fortunate to have picked up this parts car as an insurance policy). It's FAR cleaner than the one in my keeper car: it's from here in the PNW; keeper car is from Illinois area [was garaged but lots of oxidized and rusty bits, most which I'll be able to remedy via stuff from the parts car).
Compression test (cold because the t-stat is stuck open on this engine) showed good balance among the cylinders. That and that it runs very strong gives me some assurance that all this work is going to be worth it.
I'm making lemonade from the lemon The GP issue gave me the excuse to make the swap using a much cleaner-looking engine and trans (also subframe and steering rack). Both engines run/ran great. The one with the bad head will be sold at some point: I have a potential buyer; need to get my needs/parts taken care of before selling.
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Many thanks, Frank, for signing up and posting here. [I'm a long-time TDIclub member - "UhOh" and am quite familiar with Frank's stellar reputation.]
