Ben in Plano, TX

I have my motor out of my 97 993S for a 'freshening' and thought I would share what the techs have found (and I have witnessed personally) so far.

1) Leaking case through bolt
2) Collapsed lifters (10 of 12)
3) Cracked plastic intake spacers (these are the 3-4" tall spacers between the intake heads and the VRAM manifold.
4) Spark plug wires are oil soaked and cracking
5) Two cylinders have visible moderate vertical scoring marks - all have signs of piston ring wear around the top of the cylinder (worn rings leads to wobbly pistons at the top of the piston travel - you get perimeter marks around the cylinder at the top when this happens)
6) SAI ports are about halfway open - still showing about a 1/8" diameter passageway.

Note that I live in a hot climate (Texas) and have DE'd the car for 50+ track days so my wear would be expected to be on the high side given the use the car gets.

I did have poor compression/leak down results on two cylinders (I think it was the same two that have the ring wear signs) a few months back and my car dynoed about 20 hp lower the 'normal' for 993's on a DynoJet several months ago.

So none of this really surprises me and since I've turned the car back into a daily driver with the comfy Euro M030 suspension set up and Sparco Milano seats I'm going to invest in a thorough rebuild to bring the motor back to stock conditions. I'm probably going to open up the bottom of the motor to inspect the main bearings because at this point the additonal cost will be trivial if it is labor only - and if the bearings are showing wear it would be a real shame to do all the other work just to then spin a bearing...

Ben



Check out the lifter in this picture - the o-ring on all but two of them were GONE - the just fell out in the techs hands as he was pulling out the rocker arms.


Here you can see all the oil caked up on the motor from the through bolt leak


More oil mess....

Ben in Plano, TX

I also will be fixing:

7) Howling A/C compressor
8) Broken door check strap
9) Jacked up jack points
10) Adding auxiliary oil cooler

Ben

jonathank2000

Ben,
Wow, great photos and info!! Thanks for sharing. I also did the same after 65K miles and found rear main seal to be replaced.

Ben in Plano, TX

Jonathan,

I'll probably replace the RMS but it is good because it went in with the RS Clutch/LWF about a year ago.

Looking forward to a strong motor after all this is complete.

Dan V

Ben,

How was your oil consumption -- under 1 qt / 2K miles?

TIA
Dan

amfp

Ben,

Thanks for sharing. How many miles do you have on your car ? Also with 50 track days - any repairs required to trans or clutch ?

Greg Fishman

Ben,
Are you changing to solid lifters and having the cam timing checked?

Ben in Plano, TX

Dan - oil consumption was ~ 1qt/1500 miles - not too bad.

Mo - 75k - tranny is good - clutch new about 5k miles ago when changed to RS/LWF setup

Greg - I'm going stock but will have a new cam chain (old one maybe stretched) installed and timing set with Porsche special tool. From people I trust I get differing opines about 964 backdating, manual timing, etc. I'm using the RUF shop in Dallas and they have checked with the RufMeisters in Pfaffenhausen and they DON'T recommend manual timing in non-race motors. Their experience is that new cam chains, new ramps if wear shows, factory cams, factory timing brings you back to factory HP rating. Perhaps Rennlist heresy but I would submit these guys know what they are talking about. BTW - they'll do anything I want (and am willing to pay for) but really don't suggest much other than factory setup for a street 993. They can approximate RS setup with 3.8 P/C, sport cat, and ECU reflash and I have considered that option but think I will remain stock and save the sport cat & ECU $$. I will be doing 3.6 P/C to correct the two 'bad' ones and set up the motor for another 100k solid miles.

Ben

Ben in Plano, TX

Mo,

I think the clutch would have needed replacement at 60-75K miles track or no track. And my DMF failed so I went with better/cheaper LWF when I replaced.

Rick Lee

Awesome! Totally awesome! I want to send you beer for DIY'ing this. Please keep us updated with photos and cost. Can't wait to do this on mine.

Ben in Plano, TX

I wish I could claim a DIY - Sorry Rick - even though I'm a former NC boy and not afraid to take anything apart I just don't have time for it right now.

Work is being done by my good friends at RUF here in Dallas. I just go over and take pictures when I have a chance....as such - you might not want to hear about the cost!

Ben

Luis A.

Hey Ben,

Nice post; thanks for sharing.

What practical and observable consequence did collapsed lifters have? Do they impact oil consumption?

Ben in Plano, TX

Luis,

collapsed lifters = clackity, clackity - it was audible valve train noise.

Quiet motor = happy lifters. I really think the TX heat + heavy DE usage led to my lifter demise. Probably accelerating what will happen in time to most of these lifters.

24FPS

ditto. also, nice to see your 993 in the background. & bol in the refresh. sounds like it'll be better than new when finished. sweetness.

Ben in Plano, TX

24fps,

Thanks - however that is a polar silver turbo that has also been recently refreshed at RUF.

Here's a pic of my car sans motor....



Ben