928 at last

Finished up the TB/WP last night........
Note: Not my first time doing this procedure....
P"Kensioner System - Gates Racing - New Laso,
Belt tracking where the last one did - no worries (Turned over several (8) times by hand..
Fired it up, waited for the computer to get it's act together and the idle to stabilize and temp to come up....
AND...
It's leaking coolant onto the oil pan from somewhere above the PS side of the crank snout, and the belt has tracked all the way to the front of the cam sprockets....
Should note it's only leaking under pressure. It quit when the engine cooled down a bit.
Pulley and Tensioner replaced this round, along with the crank sprocket.
Any words of advice or any thoughts on what the hell is going on?
TIA!

SeanR

Early or late water pump?

Reason asking is the later pump has the tension arm carrier on it and the early pumps do not. Early pumps have a hole that needs to be plugged.

Belt tracking to the front is usually because the front crank gear washer is missing.

Anyway you look at it, you are going to have to tear it down again so you can get a better look.

928 at last

Late ..... hole sealed with the allen screw and thread seal (Permatex).
Front crank gear washer? You mean the "Guide Plates" on each side of the gear?

Picked up a pressure tester today to see exactly where the leak's coming from when I get back in......

Mrmerlin

IIRC both pumps need to have the tensioner pivot hole plugged and use some PTFE sealant on the plug so it wont leak.

Did you inspect the insides of the hoses where they attach to the water bridge,
there are small nubs on the top of each outlet that will indent the hose,
and if the hose is old then this can cause a leak ,
there is a circlip on the top radiator hose at the bridge this can do the same thing.

The Porkensioner isnt vary hard to install but you do have to pay attention to how it is done maybe you dont have the tensioner lined up correctly,
or as Sean suggests that the front thrust washer is missing

SeanR

I leave the guide rod/arm attachment on the later pumps in place. No need to pull it out on those pumps. They are already sealed up and do not interfere with the belt tracking at all. Pulling it off will cause more problems (leaks) than it solves by removing it.

928 at last

Just pressurized the system cold to 12 psi.....there's a leak I wasn't aware of at the PS of the rad.....hope it isn't the tank seal.....
Nothing evident from the engine. I wonder if it needs to be hot to leak....
If you mean 928 102 124 01, there's a new one in there, and both 928 102 125 02 s are in there as well...and oriented the right way....
Are there any other washers or plates that should be there?

928 at last

But, I was following directions.......

worf928

There are two guide pins for the water pump on the block. The holes for the pins on the Lasos are exactly the right size. Any bit of corrosion on the pins and the pump won't seat flush. And the 10 N-m of torque on the water pump bolts won't do the trick either.

My bet is that the pump didn't seal at the bottom due to the above.

With the Laso's I usually file-out the holes for the guide pins ever-so-slightly and inspect the seal with a mirror after dry fitting the pump with no gasket.

928 at last

I'll check that before the pump comes back off...

928 at last

OK,
No rad leak......**** poor clamp job.......it was midnight..what can I say.
At 13 psi, it's dribbling down the front of the engine now...
Going back in now...

Mrmerlin

Dave brings up a good point,

did you do any prefitting of the pump and file out the alignment holes with a rat tail file?,
This is done without the gasket in place?

Every Laso needs to have this done due to the close tolerances of the holes.

SeanR

News to me as I have never done this.

j.kenzie@sbcglobal.net

Should WP gasket be installed dry or with sealant?

SeanR

That's typically a personal preference.

I know GB puts them on dry and I'll use a very small coating of Victor Reinz on both sides.

928 at last

I'm really **** about working on this car. and, last time, no rat tail and no issues...Laso then too. However, I'm betting Dave's right. We'll know in a couple hours....
It was tight, but so was the last one IIRC.
Wish I'd known that before I buttoned it up.