Syncro TDI Info and the WBX Conundrum

[outwesty]

oops double post

[Christopher Schimke]

Okay, AHU questions.

I was playing with my engine today and was preparing to change the timing belt. In turning the engine over, something didn't feel right. It wasn't quite stopping, bit it had a spot in it that felt odd, like a valve was lightly touching the piston or something. I made the decision to pull the head and I'm glad that I did.

The valves and pistons were just fine. They look pretty close to new as a matter of fact. What I think I felt was the injection pump ramping up (live and learn). But what I did discover were a few things that I need to address before the engine gets installed.

Issue #1 -
The first thing I found was that the intermediate shaft has a lot of play in it. Looking at the bearing, it is obvious that it is worn in the direction of the load from the belt tension. Tolerances feel okay up and down, but the side to side tolerance is pretty severe. The bearing isn't torn up or anything, just worn smooth on one side.

Here's the question: What are the chances that the bearing on the pulley is worn but the bearing on the flywheel end is still okay? The only reason I ask this is because changing the pulley end bearing is dead easy, but the bearing at the flywheel end is buried in the block and is going to be a bit harder to change without special tools. I'm willing to make the necessary tools if I really need to change that bearing. Just asking what the more experienced would do about that bearing near the flywheel end.

Issue #2 -
The camshaft lobes look pretty good, but the seal surface has a pretty nice ridge carved into it. In addition, some of the lifters have some pitting (that's not rust, it's just a weird reflection on the lifters).

The question: Do I replace the cam with a stock replacement camshaft or is there something better?

And lastly, are the ARP head stud a worthwhile investment or are the stock style bolts sufficient? I have no problem spending the money on the ARPs if they are better, but I'm not building a mega hot rodded TDI so if the stock bolts do a good job with a slightly warmed over (at most) TDI, then I would rather spend my money somewhere else.

Any other words of advise while I'm in this deep? I'm going to check the crank bearings, but anything else?
_________________
"Sometimes you have to build a box to think outside of." - Bruce (not Springsteen)

*Custom wheel hardware for Audi/VW, Porsche and Mercedes wheels - Urethane Suspension Bushings*
T3Technique.com or contact me at [email protected]

[hans j]

I won't build another engine without replacing the intermediate shaft bearings! I used a tool similar to this to do mine: http://www.summitracing.com/parts/aaf-all96470?sei...Atol8P8HAQ

Since you are taking it apart...

I had all my parts balanced, only cost $100 or so. I also went with next oversize pistons since my bores were scored.

Sometimes cams can be fixed with a sleeve, or seal moved back and forth around the groove. But if those lifters aren't flat and are dished, I'd replace all lifters and cam.

If you are checking rod and crank bearings, just replace them

Stock ALH rod bolts are extremely strong and I believe the AHU was the first to use that rod. I'd check with tdiclub.com on that one.

Don't forget to take note of how many holes are in the head gasket, they measure the compression ratio.
_________________
1986 Canadian Syncro Westy TDI - 1989 Syncro Single Cab - 2001 Audi S4 - 1981 VW Caddy ABA - 1980 VW Caddy EV - 1973 VW T-181

[?Waldo?]

You can sleeve the cam. The Timken part number is KWK99128. I would replace the lifters. The cam is usually fine.

The outer intermediate shaft bearing usually wears a lot more than the inner one.

Here's a pic of the two tools I use:

Make sure you align the oil hole properly. Also, the inner bearing has a slot in it that jets oil at the vac pump drive gear. If you replace the inner bearing be sure to orient that the correct direction.

The rod and main bolts are single-use.

The stock head bolts will be fine.

I like to use a very light coating of hylomar spray on both sides of the head gasket, the head surface, and the block surface. It eliminates the fairly common oil leak that occurs between cyl 3+4 where the pressurized oil travels up to the head.

[tjet]

Does anyone know if these main studs will work in an AHU TDI?

http://arp-bolts.com/kits/ARPkit-detail.php?RecordID=1190

[AndyBees]

[size=18]

tjet wrote:

Does anyone know if these main studs will work in an AHU TDI? http://arp-bolts.com/kits/ARPkit-detail.php?RecordID=1190

Maybe this will be helpful. In the link, scroll down to see applications!

http://www.idparts.com/arp-head-stud-kit-ahu-1z-alh-p-3327.html

EDIT: Here is the link that shows fitment for rod bolts (sorry about the mix-up)

http://www.idparts.com/connecting-rod-bolt-1zahualh-p-1463.html[/size]
_________________
'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[?Waldo?]

It appears that tjet is asking about main studs not head studs. I have not yet fitted arp main studs on the AHU. I've fitted several sets to earlier engines (1.6TD/AAZ), but the bolts are different so I do not know if the same stud kit will work.

[tjet]

Thanks guys. I will contact ARP to confirm.

[Zeitgeist 13]

Just curious, but is there a benefit to running ARP studs vs stock bolts on the mains?
_________________
Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[westyventures]

[westyventures]

On a related subject, has anyone here found a source for the 028105701H upper rod bearings? These are 'sputter' bearings and supposedly withstand a bit more stress than the standard version. Before installing my engine I'd like everything to be 'the best' as I'm aiming for 275-300 ft/lbs in an mTDI.

[tjet]

[Christopher Schimke]

Hans, Andrew, thanks for the info. I pulled the main and rod caps and it looks like the prudent move is a complete rebuild. The rod bearings look brand spankin' new, but a couple of the main bearings have issues. Number one main bearing has some really odd wear. The wear is only on one side (turbo side) of the bearing and it looks like the crank hasn't even touched the other side. Very odd! Number two main bearing has some "normal" looking wear with maybe slightly more wear on the turbo side, but not much. The rest of the main bearings look pretty good.

The cylinder bores still have some cross hatching on them, but one cylinder has a weird radial groove in it and another other has one odd small pit that look like a casting flaw.

I'm going to drop it off at the machine shop to see what they say.

A complete rebuild is definitely not what I had planned on, but after buying two bum complete engines, I'm not risking a third. I'll just do it right and be done with it.

Since the only visible issue with the camshaft is the groove on the seal surface, should I just reuse it with new lifters or go new?

Anything else that I should consider while I'm spending the kids' lunch money?
_________________
"Sometimes you have to build a box to think outside of." - Bruce (not Springsteen)

*Custom wheel hardware for Audi/VW, Porsche and Mercedes wheels - Urethane Suspension Bushings*
T3Technique.com or contact me at [email protected]

[?Waldo?]

I would put a sleeve on the cam and use it with new lifters.

[AndyBees]

[Zeitgeist 13]

Are these main studs intended primarily to be used with the engine girdles on these engines?
_________________
Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[tjet]

[Christopher Schimke]

[tjet]

[westyventures]

I can't find the box, but did locate the invoice: I first tried the 5402, which did not work, then ordered 204-5408 which did.