After 600 miles, I got 2 cracked main caps. What the heck.

[theman53]

http://www.summitracing.com/parts/arp-204-5403

Makes it even cheaper. Like I said, Summit usually sells arp stuff about the best of anyone.

But then there is always EBAY
http://www.ebay.com/itm/ARP-MAIN-STUDS-VW-RABBIT-GOLF-JETTA-1-8L-2-0L-204-5402-/300625447233?pt=Race_Car_Parts&hash=item45feac4941&vxp=mtr

[CdnVWJunkie]

After pulling out all the parts from the block, I saw the rod bearings have this wear pattern. It looks like pre-detonation. Or is it oil starvation? I've seen oil starvation as grooves or pealing of the bearing surface.
Again never seen this in any engine overhaul I've done. This is only after 600 miles of running.
Any body seen this before?

It almost looks etched.  Can you feel the unusual pattern with your finger Tony?

[TonyTDTruck]

 

It almost looks etched.  Can you feel the unusual pattern with your finger Tony?
[/quote]

Yes it feels rough on the fingernail. All 4 are just like that. Tiny cracks like it was pounding them to death.

theman53, this the rod end I'm holding in my hand.

[Toby]

How much ether did it take to get it started the first time?

[CdnVWJunkie]

That's just strange.  You'd never guess looking at those you have so little miles on them.  What did you put on the bearing upon assembly?  I wonder if you had some strange oil on your hands that etched those bearings?  Did you plasti-gauge them after install?

[CrazyAndy]

Were you sure that you were getting oil to these bearings?  It looks like they were running dry, just taking a pounding from the crank!  I ask the same thing as Cdn above, what assembly lube were you using?

[Gizmoman]

Did you put some sealant on the squirters. I think Theman mentioned somewhere that no sealant under them can = low oil pressure.

[TonyTDTruck]

That's just strange.  You'd never guess looking at those you have so little miles on them.  What did you put on the bearing upon assembly?  I wonder if you had some strange oil on your hands that etched those bearings?  Did you plasti-gauge them after install?

I actually run the auxiliary shaft that runs the oil pump with an electric drill to prime the engine with motor oil.
That way I'm sure the pump is ready to go. Especially when it's a new pump. As soon as the starter goes oil is being pumped.
I noticed that when the main bearing caps went at 65mph, the oil pressure light came on. That told me that the crank was not contacting the bearings allowing the oil pressure to drop.
I didn't drive it for very long though. When the bearing caps went, the vibration from the engine made me let off the gas and move to the shoulder.
It could be lack of oil for a few seconds. Not sure though.
I got a hold of everything I need to take the block to a machine shop for inspection and repairs if needed. I also got a hold of a TDI crank that will take place of the AAZ crank. The TDI crank may need to be turned. Non the less, it will be done right.

Gizmoman , I have never heard of sealant for the squirters. I didn't know they could leak.

[Syncroincity]

I think the squirters thing is in the event they actually fall out (perhaps due to lack of sealant or lock-tite) the oil will hose out of the large bore hole and reduce the feed to the bearings.

[theman53]

I didn't experience it personally but no. The oil was leaking by a guys oil squirters as he didn't put the anaerobic sealer recommended by vw on them. You could put hylomar or if you never wanted to get them out a bearing and sleeve retainer compound. Vince Waldon was the guy that asked the other guy on here having problems if he used sealant. The guy said no, tore his engine down, used sealant, put it together and all the sudden had oil pressure. I think it is a rarity, as the total of all 4 oil squirters should leak less than 1 main bearing, but vw put sealant on them for a reason. I bet it was a just in case the tolerances of both parts were way off and caused low oil pressure.

FWIW, I don't think in 1 mile with no oil those bearings would look like that. My friend at an import shop ran one for 15 minutes without oil trying to blow up an 8v for a customer. The rings were toast after but it wouldn't blow up. I am not saying it is impossible, but it just seems unlikely. Also, what is wrong with your crank that you are going to a TDI one? I would have taken the aaz crank for inspection and cut a D sprocket into it.

[hillfolk'r]

That etched look kinda looks like fatigue stress or glycol poisining. 
More like fatigue though that must have occurred as everything started moving around before it really came apart

[theman53]

http://www.ngpracing.com/newstore/eurospec-sport-billet-main-bearing-caps-all-vw-audi-4-cylinder-5-piece-kit.html

solution^

[TonyTDTruck]

http://www.ngpracing.com/newstore/eurospec-sport-billet-main-bearing-caps-all-vw-audi-4-cylinder-5-piece-kit.html

solution^

Yea this is a good solution. I got a hold of an original set. I believe that the original ones with ARP studs will work. If I was doing a race engine I would probably consider these billet caps. But then, what the hell do I know about crank forces and stretch bolts. 
I have the block and parts at a machine shop now. I won't know till next week if this block can be saved without spending a whole lot of money.
This engine has, gotten a whole lot of love though.

[Syncroincity]

Any updates, Tony?

[TonyTDTruck]

Yea sorry about the delay. I've been pretty disgusted with the machine shops around here. I'm being told that they can't guarantee the top of piston after line boring the block. So even after trying I would have to pay around $280. I think it's better to find a short block and start over.  One of the problems I'm having is, no answers about what caused the main caps to break, and then the bearings look like they ran out of oil. Both of the machine shops couldn't figure out what happened. After all of that, I would need new bearings, head gasket, piston rings......
I'm considering selling my new cylinder head with only 600 miles, and the Giles pump.
The block with TDI crank and a set of main caps is going as well. In the mean time I have gotten a hold of a TDI AHU motor I'm getting ready to install in my DoKa.
Back to square 1 with getting an engine back in my truck.
s**t on a stick.