Deb

I've been reading the threads on these topics & have applied the usual good advice but still have the problems?
Oil pressure gauge always remains between 4.5 to 5.0 depending on RPM's, the temp gauge rarely varies -runs at mid point- the oil press ga. fluctuations are very smooth -not bouncing around as most report but stay near 5- Issue or normal presure?
Bled brakes all round, master cylinder, slave - brakes are perfect but unable to get clutch pedal set up with normal pressure. Pedal drops to half travel before engaging and requires double/triple clutching and still doesn't always allow shifting without alot of careful shifter manuvering. Used vacuum bleeder; have bled quarts of fluid to no avail, also had a wrench do a bleed and nothing has changed.
I intend to check the disc plate spacing but that won't answer the soft pedal .
There are no leaks at the master or slave; have also unbolted the slave and did the "push the piston back by hand" -no improvement. Any wisdom out there??

Doug Hillary

Hi Deb,
I like your extra "gear" - I sold my lovely '72 MGB some years ago for a Z3 2.8 BMW.
When working for BMC in NZ I helped to develop/refine the first export Series 2 MG Midget in 1962

The only parameter for oil pressure monitoring with a 928 is with the oil at 90-100C the OP sould be 4 or 5bar at 4 or 5000rpm. Reading this reference may help you;

http://www.landsharkoz.com/techtips.htm

Check under "Lubricants for the 928"

You will get a lower OP reading at idle with oils having a viscosity such as <10w-XX. This is of no consequence as long as your gauge is reading around 1.5bar> and the OP light does not come on.
Mobil synthetics and some others too tend to have lower readings at idle but the more important issue is that OIL FLOW is being maintained anyway

I live on the edge of the Great Barrier Reef so boating is a way of life here. We have about six ex America Cup yachts based here too

Regards
Doug

jon928se

Deb

bleeding the clutch is a dark secret. The main problem is that air gets trapped in the top of the master clylinder not the slave and it won't come out using normal bleeding techniques because the new fluid just flows past it.

The quick way I have found is to use a pressure bleeder until no more bubbles come out of the slave cylinder bleed nipple.

Then thro' the inspection port in the bottom of the bellhousing slowly push the slave cylinder pushrod back in to the cylinder as far as it will go and hold it there. Your assistand will see bubbles coming up into the reservoir. Repeat this a few times allowing lots of time for the bubbles to rise and the new fluid to flow down when you let go of the pushrod.

What you are doing is backflushing the system so it pays to do it gently and slowly.

Regards

Jon
Black SE
New clutch flexi hose fitted last week - over and hour to tighten three hose connections - 5 minutes to bleed clutch and get rid of any air.

Deb

Hi Doug - Great Site, much info well organized and to the point!
I will be switching to a Syn Oil at next change, I've been hesitant because of other info sources relating leaking seals after switching to syn. but there is much competing info. on that topic.
Oil change frequency and timing for same - - all of my collected info (both cars and boat) strongly recommends that the oil change always be done just prior to laying up the engine for winter so that the accumulated acids don't affect the innards. I suppose that you don't have to put your cars to bed for winters but snow, road salt and -40 Degree C. temps do no favours to a Shark. Anyway, after a 4 month layup it is just like getting into a new car and experiencing all that a Shark has to offer.
The boat, like the Shark, is a demanding mistress from a maintenance aspect but, like the Shark, it has to be done routinely or pay the consequences. We normally sail the Carribean Islands from Sept. to May so open water ocean sailing also demands that everything be in prime condition.
Thanks for the info

Deb

Jon, thanks for the reply. I used a vacuum bleeder which may not be as goood as the pressure bleeder but seems to do a good job normally.
I have "done" the manual "push the piston" back but the extra aspect of an assistant watching for air bubbles in the master sounds like a worthwhile modification to the procedure - - will try this as soon as my "assistant" rolls outa the sack.

WallyP

Last resort for bleeding the clutch...

Disconnect the pedal rod.
Remove the boot and snap ring.
Pull the piston out until it is ALMOST out of the bore.
Tilt the piston so that the top edge only of the seal clears the bore and lets the air out.
Reassemble.

I think that Jay Kempf came up with this...

mspiegle

the pull-the-slave-cyl-off-and-push-rod-in-while-screw-is-open method has never failed me.

Rez

What I did was unbolt the slave. The hyrdrulic line prevented me from pulling it all the was out, so the pushrod was still in there. I was able to pull it out far enough to get a small block of wood in the inspectine hole. Then I pushed the Slave into the wood, ultimately pushing the pushrod into the slave cylinder. Subsequently, when I opened the bleeder, bubbles came pouring out.

I would rebuild the Slave too. You can order a clutch slave rebuild kit from NAPA for $30. Mine was toast and is much happier now.