Jeff Curtis

I pulled my engine/trans. on Saturday, due to the fact that I'm performing a valve adjustment, replacement of several seals/gaskets and some modifications.

I'm also investigating the origin of an oily/greasy substance that is splattered all over the inside of my bellhousing, and consequently on the clutch...which was really the main reason to remove it, the fact that I'm performing the valve adjust, etc. were just "bonus" reasons.

As I check my dist. belt prior to each track event, and every few weeks in between, using a timing light...I began to wonder if this would be an opportune time to send the distributor out to get re-fitted with a fresh belt??

Upon removing the distributor, and it's caps/rotors, I was investigating the belt as best I could by rotating the dist. by hand and using a bright light.

The belt looks to be in good shape, the teeth and rubber look great. The writing on the belt is nice and bright white, the belt driven side has silicone sealant rubbed all over the bottom (exterior) of the housing...seeming to hold something in, I'll investigate that later.

My question is: as it seems the dist. belt may have been replaced by PO, are the original belts manufactured by "Gates"?? This one has bright white writing on it, a bunch of numbers and "Gates" which I know to be a major belt manufacturer.

I'm hoping this would be a simple way of verifying that the belt indeed has been changed. My other indication, while slight, would be that I have an early '91, that someone has installed a dist. vent kit on, and of course, the silicone on the bottom of the belt-driven housing.

So basically, I look to hear that the ORIGINAL belt had "Porsche" or some other markings/manufacturer written on it - then that would comfort me in knowing that it has been replaced.

Could anyone that suspects they have NOT had the dist. belt replaced check for me? -or- does anyone just simply know what the original belts had on them? <img src="confused.gif" border="0">

Adrian

Dear Jeff,
It is my understanding that the original belts "were not Gates" belts but Bosch belts which both Bosch and Porsche refused to sell as separate items. The trashed belts that I have seen photos of, had no visible markings on them.
I feel that your belt has been replaced since 1991. However if in doubt, replace whilst you have the chance. Seeing as you spend some time on the track, maybe a distributor overhaul would be a good idea anyway.
Ciao,
Adrian
911C4

Jeff Curtis

Good news then, that's what I figured...but let's keep the survey going - my confidence is building with each response!

John Miles

You may think Jeff is a little paranoid, checking his belt so often.

Not the case, he has seen the damage caused when 964s with broken belts are driven hard on track. His story is up on my site.
<a href="http://www.porsche964.co.uk" target="_blank">www.porsche964.co.uk</a> - click the 'broken distributor belt' link on the 'Technical'page.
John

horst

Jeff, while you have it out, also consider replacing the power steering belt. As with everything else, it will be much easier with the engine out.

speedster 94

hallo
If your Dist. has been replaced by the updated one
it says Z behind the Partsnumber stamped in.The original Belt is from Bosch,at least the ones i looked at ,and that was more than a few.
Harald

horst

speedster, where on the dist is the parts Nr.?

speedster 94

hallo
The numbers are on the Distributor itself ,right under the Two round pots holdind the Caps .
Harald

horst

Danke, Harald

Rich W

Jeff,

The belt removed from my car at the 60k service is a Gates 501AG.

And why didn't you let me know about the autocross? <img src="confused.gif" border="0">

Jeff Curtis

Horst, thanks for the power steering belt suggestion, already had one in hand...I actually spent about $600 in maintenance parts already, and put in an order for some more stuff today. The leakage is either from the trans main shaft seal, the power steering housing or the oil thermostat on top of the engine.

I can't tell if it's motor oil or gear lube, being that it's Mobil One all the way around, the gear lube doesn't have that "funk" like your average gear lube...but the buildup of crap sprayed all around the inside of the bellhousing seems to have a sticky property...suggesting it's gear lube.

Either way, replaced the power steering belt, power steering housing seal and O-ring, thermostat O-ring, crankcase breather gasket, trans. main shaft seal and differential cover O-ring, timing chain cover gaskets and associated tensioner cover gaskets...and of course...valve cover gaskets.

I have pretty much settled on the fact that it appears the distributor belt has been replaced...it's WAY too new looking, and the distributor housing has evidence of being "tampered" with.

Hopefully all this replacing of various seals nips the MAJOR leak in the butt, whatever it was...still, even with the fuel injection/intake off the motor - it's hard to tell the source of the leak.

Everything will be going back in with new seals/gaskets/O-rings abound, new (factory) plug wires, plugs, caps/rotors, underdriven pulley mod, new belts/hoses, Euro-premuffler, performance primary muffler with NO secondary, a chip and a fresh valve adjustment.

You should see my garage!

I'd BETTER feel an improvement in the "butt-dyno"!!

George Stevens

Jeff

Just keep saying to your self

It will all go back together again
It will all work
I will drive this car again this year
It will all be worth it!!!

91C2wrencher

Jeff, from the description of your distributor I'd reason a guess that it's already been serviced and probably from Steve Wiener. I had him do mine and it sounds like a similar repair, do you have four small holes drilled into the base section for ventilation?...I might also highly recommend that you have the cam shaft seal for the power steering drive changed. this is a simple job with engine out(not so with it in) seal is $70, this is becoming the next thing to leak on these cars.

horst

Jeff: re the black gunk. I am also Mobil I all the way, and once in a while, I see a dime sized spot of black gunk on the floor. I believe that this may be a tiny bit of tranny lube sneaking past the shaft, running down the bell housing & picking up old crap, clutch dust, etc before it exits. Since I have not yet jerked my engine out, I can't say what the state of cleanlieness is inside the bell housing. You can. What did it look like?

Jeff Curtis

91C2wrencher...I'm all over the camshaft to power steering housing seal and O-ring like a bum on a bologna sandwich...I am really thinking it's either that or the main shaft seal on the trans. that was causing the mess...or BOTH!

You said, "have it changed"?? No, no, no...I will change it!

Horst, it really was a mess in there, the clutch is okay, thank God, it just seems that Mobil-One was seeping past the main shaft seal and getting flung around inside the bell housing...that, coupled with the wear of clutch material - made this nice substance that I actually had to SCRAPE off the inside of the bellhousing.

Well, after two LARGE bottles of Simple Green and several drive-bys that have wide-eyed people asking themselves or their better halves, "what the hell is that guy doing??" I can say I have the cleanest transmission, intake system and engine in a five mile radius...okay, maybe 10 miles?

If my efforts have conquered half the sources of the oil leaks on my drivetrain - I'm happy, if not, maybe it's time for a Vette? ...NOT!!

George, thanks for the "self help" advice, I need it! I've had this car apart before, actually, the second day I owned it as it had clutch issues upon purchase...I just shake my head at the thought that I actually had tunnel vision and didn't take care of a few issues that I know damned well I should have while I had it apart! After all, this IS my second 911, this drivetrain isn't all that different from an SC drivetrain, same sources for leaks, literally! (even most of the part#s are the same)

FYI, I watched the startup of my friend's engine this evening, the one that was damaged due to a broken distributor belt, (see picture above, taken by me, posted by John Miles) you should've seen the look on my friend's face...he has been without his "baby" since last October. He had a 3.8RS conversion kit installed, complete with the opened-up heads and all, pretty neat...I can't wait to still whip his butt on the track!