Leaking around speedometer at tranny

[Stanley_P]

I'm leaking some tranny fluid from the speedometer at the transmission.
Is there an o-ring that goes onto the cable or is the only seal on the blue
speedo-gear?

Stanley_P

[namba209 (R.I.P.)]

Stanley, Lyle (Tru-Craft) just posted a thread yesterday on his broken tranny 90 degree adapter. In that thread is a breakdown of the 90 degree drive and it shows an O-Ring on the drive adapter that goes in the tranny. Check it out, it may be of assistance to you.

[RallyBob]

I'm leaking some tranny fluid from the speedometer at the transmission.
Is there an o-ring that goes onto the cable or is the only seal on the blue
speedo-gear?

Stanley_P

On a 1973 GT, the speedometer drive is straight (not the earlier 90 degree type). There is a small cup seal on the plastic driven gear within the speedometer drive unit, and there is an o-ring on the perimeter of the speedometer drive unit, where it inserts into the tailshaft of the transmission. The cup seal is the more common failure point, and it also happens to be a difficult-to-find item. Opel GT Source is your best choice for finding one.

Bob

[namba209 (R.I.P.)]

Thanx for the expertise on that, Bob. It's always welcome. I've never had a problem in that area, so I'm not sure what goes where.

[Stanley_P]

Thanks for the info.
I going to take it out this weekend and find out what's up.

Stanley

[Tru-Craft]

Stanley, is the speedometer drive assembly in the transmission simular to the early type?
Post some pictures in the speedometer rebuild thread I started, then we will be able to fix both types.
Lyle

[David McCollam]

Bob,

How do you get the speedo drive apart to replace that cup seal? I've had it out of the tranny to replace the o-ring and have a cup seal, but was unable to determine how to disassemble the drive to install the cup seal.

Also, the automatic transmission in my Sport Wagon is coming out. Would you recommend converting to a 4-speed? Just tired of messing with the automatic.

Thanks,

Dave

[GTJIM]

Also, the automatic transmission in my Sport Wagon is coming out. Would you recommend converting to a 4-speed? Just tired of messing with the automatic. Thanks, Dave

Replacing the auto with a four-speed will be a LOT more work than sorting out the auto trans! So many more bits are needed for the clutch mechanism alone. A four-speed will give a bit more 'performance' but the auto should be much more user-friendly in daily driving. The Opel TH180 autos are very strong and usually only need new seals front and rear plus a change of fluid and filter to carry on for years and years.

Just like all GM Turbo-Hydros care must be taken to get the oil pump drive on the convertor properly engaged when refitting the box - best to slide the convertor into place before fitting the box and attaching it to the flex plate after the box is back in.

[David McCollam]

Jim and company,

This is the saga of the automatic transmission. When I got the car the rear main oil seal was leaking. Simple, remove transmission and replace seal, right? Took it to the shop. Shop replaced seal, no problem. Shop broke transmission converter pump housing installing transmission, big problem.

Gene Smith sent replacement housing. Took housing to shop. Shop installs housing on transmission. Transmission back in car. Two days later, transmission is buzzing. Car back to shop, transmission back out. Washers in pump have slipped, pump gears broken. Transmission shop replace pump gears and reassembles transmission. Transmission back in car. Car back home.

One week later testing another fix on car, transmission shifts from 2 to 3 and engine revs like no load on drivetrain. Bring car to a stop at stop sign. Car returns to idle. Press accelerator, no drive, no reverse, no gears. Push car back home. Linkage connected, vacuum line in place, oil level normal, no externally visible sign of a problem. Manual indicates block suction screen, low oil level, jammed high pressure valve, disconnected shift linkage, broken input shaft or failed oil pump.

Tow car to shop. Transmission back out of car. Car starts and idles and revs great, no motion.

I have all or almost all of the parts for conversion to manual. Need advice or crowd on direction to proceed.

Thanks,

Dave

[GTJIM]

That Trans shop dserves to go out of business - the mistakes they made and the parts broken is the work of total clutzes. By the sound of it bits of broken pump have been pushed around the whole hydraulic circuits inside the trans - they owe you a total rebuild.

[David McCollam]

Jim,

I agree totally, but I'm now in a position of trying to figure out what course of action to pursue. I think they will make it right, but is it worth the effort to put the automatic back in.

dave

[tekenaar]

Jim,

I agree totally, but I'm now in a position of trying to figure out what course of action to pursue. I think they will make it right, but is it worth the effort to put the automatic back in.

dave

. . . like GTJim said in earlier posts, TH-180 is a very sound (read: troublefree) transmission with just the basics attended to. There is a BIG difference between "caused" and "wear" problems . . . you've experienced the former, no real reason to replace tranny because of it. That's my take on it anyway, so save yourself a lot of "conversion" headaches . . .

[David McCollam]

Meanwhile, the car I have waited a year for and spent $1000 on since I've had it sits. But, after all that's what Opels accel at, sitting while one works on them.

[opeletti75]

Meanwhile, the car I have waited a year for and spent $1000 on since I've had it sits. But, after all that's what Opels accel at, sitting while one works on them.

if you think opels accel at sitting ,sell it I'll buy it.too short too short too short

[kwilford]

How do you get the speedo drive apart to replace that cup seal? I've had it out of the tranny to replace the o-ring and have a cup seal, but was unable to determine how to disassemble the drive to install the cup seal.
Thanks,
Dave

Replied via PM, but I thought I'd also post it here:

It's been a while, and I am only really familiar with the later (non-right angle drive) speedo. But IIRC, you should remove the housing from the tranny first by removing the retaining bolt and clip and simply pulling the housing out. Then the plastic drive gear pulls out. Pry the old cup seal out (cup down) and push the new seal into the upper recess, inside the threaded part that the cable attaches to. Then push the drive gear back through the seal. You should also replace the O-ring around the housing before re-installing. HTH