dgmattingley

Here's an update on where I am:

-- Pulled the engine and tore back down to case
- Replaced the o ring for cylinder 2 base, and also replaced the o rings for the thru bolts surrounding cylinder 2, all of which were wet with oil
-- checked torque and alignment of cam towers/heads, found no problems so did not split them up
-- retimed cams, buttoned back up and installed with new starter

Now when I turn the key I just get a whirring sound from the starter but no engagement of the flywheel. The ring gear is installed. I charged the battery but haven't tested it yet, so maybe it's bad and not enough juice is getting to the starter? All the other electronics -- lights/sunroof/windows -- are working.

C4S993

Is this the first time starting the engine with the rebuilt starter ?

dgmattingley

Yes it is. I'd be suspicious of the starter, but the previous starter did the same thing once, and then after disconnecting/reconnecting worked OK. I'm thinking it is an issue with the connections but not sure yet.

C4S993

Did you check to see if the "rebuilt" starter has a working solenoid ?

Mike J

As an aside question - did you find the oil leak, i.e. damaged O rings, missing rings, damaged surfaces - any indication on why it was leaking?

Cheers,

Mike

JPP

Could this be related to the TSB on case studs coming loose and/or stretching IIRC?

Ed Hughes

I'd not think Dilivar stud issues would be the problem here. The Dilivar problem was more related to hidden corrosion and resulting breakage.

dgmattingley

The cylinder base o ring looked fine, and I found no discernible defects. I replaced it anyway. Out of the 8 through bolt o rigns I replaced, I found one that was torn. I suspect it may have torn in the removal process. As there was oil on four of the through bolts, I certainly can't say this was the culprit.

The cylinder/case looked fine, too. When reinstalling, I put a bit of Curil T on all the cylinder base O rings, and a very light coat of Threebond 1120 (think that's the number, it's white) on the case where it mates with the cylinder base.

How would you recommend I test it? I'm a neophyte in the electrical area. The starter does spin.

I tested the battery and it has a full charge. I redid the ground strap connection to the starter and now the starter briefly engages the flywheel, but sounds like for just one quick turn and then it disengages. This is whether the DME relay is in or out, same behavior.

Does it matter which of the 50A connections is on top/bottom? There is one from the harness and one from the battery.

The head studs all look great, no corrosion and the threads are perfect. I decided against replacing them.

TravisB

If the above didn't fix your leak, don't they make dyes to put in oil that show up under UV lights for tracing leaks? Would probably be quite handy, or at least give you a general direction to look towards..

JPP

The only reason I mentioned it is because that was the diagnosed cause of my oil leaks at the cylinder bases at my PPI. 'Fairly common cause of this problem on '97//98 MY 993's' was the quote ... the mechanic said the studs corrode and loosen and cause the gasket to fail ...

Ed Hughes

I'm no expert, having had a flat 6 apart and successfully back together only twice. I'd just not ever heard of a loosening issue, at least in <'89 Carreras. The only loosening was due to stud breakage that is somewhat common. Funny, when I pulled my '84 apart, the Dilivars looked fine-it was the steel studs on the other side that looked like they had 130k/24 years on them!

Mike J

If you take the starter out of the car, you can jury rig the starter off a batter charger that has a start circuit (to supply enough current). Power up the started by applying the ground to the case and the +ve to the large positive terminal, then use a jumper to activate the solenoid from the small + terminal off the end of the starter. Two things should happen, the starter should turn over and you should see the gear be pushed out (one that would engage the ring gear on the flywheel). If you are not seeing the gear being pushed out but the starter spins, the solenoid is not pushing the gear out and is faulty. Funny though, the contact to make the starter turn over is usually activated by the motion of moving the gear out.

Cheers,

Mike

C4S993

Is it possible that when the starter gear moves toward the flywheel teeth that it hits between the teeth and thus "feels" it's jammed and backs abruptly out and away from the flywheel gears ? Is there a shim adjustment required to make sure the starter pin gear meshes properly to the the flywheel teeth ?

Patrick

dgmattingley

Mike,
I have a battery charger but I'm not clear on the start circuit, can you elaborate?

Mike J

Essentially you want to power the starter directly (out of the car) so you can see its action.

It's hard to describe via text and I am doing this via memory - if I had to do this, i would figure it out as I go... It should look like this



See the big terminal at the top - that is the main power for the starter - it provides power for the motor and the solenoid. See the picture from pcarworkshop -



If you ground the starter (to the negative/black of your charger) and apply the red to the positive (the big 50AMP terminal) nothing should happen. If you also apply +v to the 30AMP terminal, it should trigger the solenoid, push out the gear and start the starter.

Cheers,

Mike