cheetah chrome

Ok so here is the dilemma(s)…

This winter’s project is to rebuild my head and reseal the front end of the motor while doing some upgrading (VR Stg II and some other goodies). I’m pretty much at the bench work stage between disassembly and reassembly of my original plan and I’m now contemplating if I should dig deeper. So I’m looking for opinions:

- I’ve already resealed the front ends of both balance shafts (new seals/new metal collars the seal rides on/onion skins). There are no sign of leaks around the balance shaft housings themselves and both shafts spin freely…should I pull the housings anyway and replace wear internals?

- Head/Exhaust/Turbo/Front end of motor are all currently off…new motor mounts/front seals/WP are in. My original plan was to do the head/front reseal/belts/rollers/WP/VR stg II this spring and lower end/clutch the following year. Since I’m this deep should I do the bottom end now and rering since the head is off…or wait and just do the bottom end next year? Cylinder bores looks great; leak down was an even across all cylinders at last check (142-145 <3%); currently I have no reason to break the bottom end open other than preventative maintenance.

Most importantly the application is a street car that won’t see the extremes of a track but will endure some spirited driving. I guess the big question is when/where do you stop the while you’re in there…

evil 944t

How many miles do you have on the rod bearings?

cheetah chrome

Car just turned 100k; no history/receipts showing rod bearing changes.

cheetah chrome

Anyone else?

kos_007

I would change the rod bearings and the oil pan gasket.

Acetylene

I just changed all seals and gaskets, except rear main, rollers, water pump, rod bearings, etc on my car. There were no maintenance receipts and I had some small oil leaks. I have 83,250 miles. I had good compression and the car ran great. I will do the internals down the road when and if...

Sounds like you are in a similar situation. My .02 would be to perform preventative maintenance and any curative items and enjoy the ride. When you pull it out in a couple of years to do the internals, you will be ready to go to a 2.8 anyway

M758

If you are doing all that why not just pull the engine and reseal it all. New main & Rod bearings, but leave the pistons in the bores. reseal everything else. Sounds like more work, but doing this on an engine stand is 100 times easier than in the car.

pete95zhn

x1

cheetah chrome

Yeah I totally agree, I guess that would of been the better question to ask...what type of failure merits a full engine rebuild. This project only started out as a HG replacement and emptying my "mods box" but has cascaded, by my own doing, into a complete dirty rebuild...for pretty much no reason other than preventative maintainence (and I don't discount PM especially in the rod bearing dept). The "while you're in there" bug seems to bite and bite hard. I thought I had planned things out well before ever turning a wrench but in hind site I should of ordered a complete rebuild kit and pulled the motor for as deep as I am digging. Unfortunately I didn't and have been ordering parts in subgroups (belts/pulleys; front seals; ps pump; oil cooler; etc...) so money hasn't been spent wisely.

Keep in mind the catalyst for all of this was a pin hole HG failure...absolutely no mixing/milkshake oil was very clean at disassembly; great hot leakdown results prior to disassembly; just some exhaust gases blowing by the HG during spirited drives. Truthfully I wouldn't of caught it as early as I did if it was a car I drove often. I put a small empty water bottle on the output of the overflow hose to monitor if I pissing out any coolant (an idea I got from a post someone had way back when) just as an added measure to watch for HG failures..since I don't drive the car much I check it before each drive. An exhaust gas contamination test in the coolant proved positive and at disassembly I found what I believe was the problem area on cylinder #4's seal ring (ironically right below the area that the Lindsey steam vent kit is installed...which there wasn't one installed on my car/nor is this a debate on whether it's snake oil or not...just an observation of mine).

Thanks for all of the opinions...as far as my project itself I'll do the lower end next year (along w/ clutch and a S2 LSD trans). Again in hind sight was it the best execution...no, but I'm surely not half assing it in anyway. The only thing lost was some money (which owning a 951 it's just the nature of the beast), the ease of wrenching on a pulled motor, and time doing a dirty rebuild instead of on a stand... Ohh well I've done dumber things in my life HA!

Thanks again!!