Barn find 79 euro

Luscombe8a · 10-22-2017, 01:56 PM

After a few days of moving equipment we pushed the 928 out into the sun for the first time in years...

Replaced the fuel pump...fuel,battery,oil & filters..runs and drives..

Need some help from some gear heads..

No dash lights..
no cruise.
no dome light

5 speed pops out of reverse without adding rpms...grinds like a mother going into 1st...but shifts fine up and down 2-5...from 1st to 2nd sounds like parts banging in a plastic cat litter box. found a replacement from a burnt unit..

Thanks in advance

harborman · harborman's Garage

Sounds like lots of cleaning of relays, CE panel, ground points for starters. Use Deoxit or other good cleaner. Cruise units are known to be an issue and may need replacement. Post some pics.

rjm65 · 10-24-2017, 09:00 PM

Quote:

Originally Posted by Luscombe8a

5 speed pops out of reverse without adding rpms...grinds like a mother going into 1st...but shifts fine up and down 2-5...from 1st to 2nd sounds like parts banging in a plastic cat litter box. found a replacement from a burnt unit..

My 79 shifted very rough when I first got it, replaced the gear oil with Redline 75w90, didn't make any difference. I then tried GM Manual Transmission Fluid p/n 88861800, that's the replacement for where the original Dexron III was approved for gearboxes (Dexron III is listed as an acceptable oil for the manual transmission in the owner's manual). Shifting quality improved substantially, although the seals began to leak slightly.

I decided to switch to Mobil 1 75w90 synthetic at the next change, shifting further improved and the leaks stopped. The GM fluid was thinner than the 75w90 so that was probably why the leaks.

The gears would grind on an upshift into 2nd with the Redline oil and downshifts into 2nd and 1st. With the GM fluid I could slowly downshift into second ok, but not first.

Now with the Mobil 1 oil, I can upshift and downshift quietly IF I don't rush it. And that is a lot cheaper and easier than having to rebuild the transmission. YMMV

Luscombe8a · 10-27-2017, 06:02 AM

Great info...will post pictures this weekend...i'm sure the trans is out to lunch & or due for a rebuild. heard the worst at about 5mph not under any real load..lots of banging going on till 2nd.fine up and down..& jumps right out of R. some 1st take offs sound like a tow truck call.