jimq

You didnt leave any loose tools back in the engine compartment did you.
Offer is still on if you need to use my lift to check it out.

vjd3

My 95 C4 sometimes made a mysterious buzzing noise on cold starts from the rear of the car, audible in the car, not so much from outside, although if it was very cold out it was loud and you could hear it from the passenger rear wheelwell. Changes as you rev the car, and seems to "overrun" a little when the revs come down. Sounds kind of like a lawnmower pullstart cord or a weedeater running. A couple of other people have the same noise. Tried a lot of things, from disconnecting the air pump belt to changing the power steering pump belt to putting a stethoscope on the chain tensioners, and never could trace it. Ironically, the 97 C2 I just bought makes the same noise.

pcar964

That's not very encouraging - if this continues, it will ruin the experience of driving the car.

viperbob

OK how about this nugget. When the DMF is having issues, it can cause the gear rattle noise in the tranny. So while you may not be feeling too much vibration, it may be enough to make the tranny noisy so you hear it in the cockpit. The tranny noise is tough to hear outside the car. Just a thought.. Also have an idea why it comes and goes. But I'll wait to tell until I get my jack pad back...

Just_rob

It is a very common occurance with these type Bosch starters, more so even on later OEM Bosch gear reduction models common on VW/Audi and very late model 911's and Boxsters.. Basically, the grease on the armature shaft gets contaminated/old/very sticky and the starter drive wont retract and it is staying engaged... If it wont start when you turn the key, the same thing holds true, there is so much contamination on the armature shaft that the solenoid doesnt have enough strength to overcome the "bind".... Hope this helps... Rob

pcar964

That is very encouraging! Anyone know how involved it is to remove and replace a start in a 993? Good price for a new or reman starter?

viperbob

If you have never done it before, prepare for lots of cussing and about 4-5 hours of work. If you have done it before, might take an hour.

Just_rob

I've never pulled one on a 993, but flat rate is 3.1 hrs so I imagine it's not too fun... It's only 2 bolts with the upper one being the PITA and its the getting to the starter and getting to the fasteners then fishing the starter out that is the trouble... Still same location, same mount, bolt pattern etc as my '78SC just crammed in much tighter....

The issue with noise if I were to wager is that the planetary gear track is probably cracked or exploded as 99% of them are in the 108/110 series Bosch gear reduction starters...

If your just getting the click click click when you try to start the car, but it wont turn over you either have a bad solenoid and it's not making a connection, or the starter drive is basically seized on the shaft and then when it finally breaks free and does turn over and your hearing strange noises and it's not engaging properly, its probably got the blown up planetary gear in the starter....

The starter on your car is a very good unit and not difficult to rebuild, the main issue with the starter is the environment it lives in with the exposure to all the clutch dust and the heat making the gear tracks brittle. Late versions of that starter have steel planetary gears instead of thermoset plastic to prevent premature failure. The main issue with your starter is the planetary shaft that the starter drive itself sits on that goes into the transaxle (much the same as early air cooled VW starters) getting too much contamination on it and causing problems..

The starters used up until the 964's had a seal on the drive end of the starter to keep all the dust out of the drive assembly, a concept that Bosch went back to in later years due to the problem your having but on the late model 996 and 997's (Boxsters as well) there is a seal in front of the bushing on the drive end of the starter that in theory would keep out the clutch dust, but there are pretty widespread issues of noisy dis-engagement of the starter due to the amount of clutch dust on the seal preventing the starter dis-engaging the flywheel on other cars using that design (VW/Audi primarily)...

If there are any other questions you have, feel free to ask and I will answer as best I can... Rob

Mike J

I had mine go and shopped around. Turned out that Weissach in Vancouver had by far the best deal (about $140CDN I seem to remember...I have to check my bills for the exact price). It did take a few hours and some cussn' to change the starter but overall not too bad (as compared to an engine rebuild)...I wrote up some notes on a previous post:

Previous Post

Cheers,

Mike

pcar964

Rob,

So few posts on Rennlist, yet you're such a wealth of knowledge! Much appreciated! When I get the starter out, I'll take some pictures and see which model it is, I'll post them here (probably next weekend before I can tackle this one)

pcar964

I'll plan on 4-5 hours then Get the jackplate yet?

pcar964

Thanks, I'll print both Robin's DIY and your addendum, and get ready for what looks like a very frustrating DIY

viperbob

I'll look at the DIY Greg and see if i have any amendments before you start.

Just_rob

Thanks for the kind words... I am a new poster to Rennlist but I've been rebuilding starters and alternators for a living since I was 16 so that certainly helps in the knowledge department...

The Bosch part # for your starter should be 0 001 110 059, or SR0429X (rebuilt) and a Porsche # of 964 604 104 00.

If I had my digital camera with me today, I would take a picture of what the geartrain in your starter looks like but I forgot it when I left the house this morning... Rob

viperbob

A couple of other things on the DIY over on p-car.com that will make it about 1000% easier. Lower the motor on the motor mounts (2 nuts) so that you can see that the nuts still have a little thread left at the bottom. Loosen the 6 bolts holding the transmission mount to the chassis down until they are close to coming out (still want a half dozen threads in contact). This will lower the motor / tranny assembly a couple of inches. Those couple of inches make all the difference in the world at getting to that upper bolt.