Engine Drop Options

[lr172]

I need to replace a starter ring and am trying to decide the best way to get to it. I was going to try the partial drop that Wayne suggests in his book to minimize the work. Then I thought about letting the engine hang and tipping the other way to drop the trans. I had dropped the trans side several inches to get the starter out and thought maybe it would tip far enough to get the trans separated from the engine. Is this possible? Is it easier to just drop the whole thing?

Thanks for your assistance.

Larry

[kodioneill]

For that repair (starter ring gear) you must pull the engine and trans as a unit. While your doing that repair take a close look at your clutch pp/tob/pb.

[willtel]

I think it would be easier to drop the whole thing. That way you can spend a fortune on lots of other little stuff you didn't know needed to be replaced.

[Gunter]

It'll go faster and better to remove engine/transmission as a unit.

You cannot leave the engine "hanging" and get the transmission out because the shift-shaft will not clear the tunnel opening.

Leaving the transmission in and removing the engine requires some skills re: alignment to slide out the spline shaft and worse, getting it aligned and back together.

Save yourself time, frustration and lots of cursing; remove the whole unit.

[Mitch Leland]

All the above for my money have it right... Plus you can do a an easy valve adjust, like kodioneill says, check out the clutch. You can do a quick wash down of the engine room and engine, there's just a lot of pluses to a full engine drop.

Just my 2 cents...

[lr172]

Thanks for the guidance here guys. I am preparing to drop the whole thing tonight. I am also ready to drop now. How heavy is the engine?

[Gunter]

Figure around 500 lbs for both.

Lots of info on removing both together if you do a search.
2 solid 4-5 ton jack stands and a floor jack with a high reach are a must.

For balance, the right spot is a little ahead of the sump plate, NOT on it!
After disconnecting the coupling, push the shift shaft into 1st or 3rd to make it easier to clear the tunnel when lowering.

Take your time and double-check that everything is disconnected.

[Mitch Leland]

Larry,

Gunter has it right, "Take your time and double-check that everything is disconnected." I think you might be making a mistake to try and do the whole thing in one night unless you have help. To be safe it really helps to have two people, you need good floor stands, you can do a search here to find out how much clearance you need under the back bumper to get the engine out from under the car.

There's a ground strap at the transmission tunnel that I missed the first time, also there's wiring on top of the transaxle that needs disconnecting. Be safe...

P.S. here's a plywood platform that I made up that drops into my floor jack pad and I can use to shim up the tranny to balance the unit as needed.

[lr172]

Thanks for the avise here. I already have everything disconnected (finished last night). I read both Bentley and Wayne's book to be sure I got everything disconnected. I did get the Speed sensor, backup, and ground strap. Thanks.

I will be doing this on a 4 post lift and only plan to drop the engine about 12" or less (just far enough to be able to separate the trans from the engine. I plan to support the engine with two (front and back of case) beams that cross the lift. I can use shims and jacks to get it there. I will pull the P Plate and ring while it is there and then button it back up. I don't intend to do any other work to the engine while it is down. It was only a few hours to get to here and don't mind doing it again during the winter for some additional work.

My plan is to support the engine with two beams / shims and the trans with another. My plan was to work the trans off with arm strength/shoulders and the beam as backup. Hence the question about weight. Is the trans about 100 lbs?

Unfortunately the car was on the lift when the ring gear got so bad that I couldn't get it started again. This is why I am doing it on the lift. This seemed like a job that would be safer on the ground.

Thanks again for your help.

Larry

[Mitch Leland]

Larry,

Sounds like you have everything well in hand. As far as the weight of the tranny is concerned I don't know... I'm guessing you're in the ball park.

[lr172]

Got it down and separated tonight. I used my teenage son for extra eyes and hands. Doing it on the lift had it's benefits, but made it tougher to get it down. I had to use a long 2X4 between the jack and the engine. Kinda scary at moments.

Thanks for the tip on the balance point. That helped a lot. People on this forum are Great!

I also tore apart the starter and found why it ate up my starter gear. There is a brass bushing inside the drive gear that rides on the armature shaft. This disintigrate and caused the nose cone bushing to wear as well. The play this caused allowed the drive gear to be loose in it's engagement and ultimately started slipping and eating up the ring gear. Fortunately I found a place local that sells starter parts and will pick up the drive gear tomorrow for $25.

The clutch disk looks good with a fair amount of life on it. The rubber center seems solid as well. There were a lot of heat spots on the P plate and flywheel. However, I am not prepared to drop a grand on a clutch right now and it behaves well.

Should I take the glaze off the flywheel and P Plate with 1000 grit sand paper or leave it as is.

For future reference, the trans is quite heavy. Hard to guess a weight, but it is easily pushing 100+ pounds. Heavier than the muncies that I would just drop on my chest.

Thanks again for your assistance.

Larry

[Walt Fricke]

Larry

You can break the glaze or not. I've done it both ways, haven't seen a difference but that is hardly definitive.

You have a rubber centered clutch disk? I thought all those had been replaced by now, though I don't see where you specify what engine you have. A 3.2?

I'd be inclined to replace the disk with a spring centered one, but that's just my prejudice. That shouldn't cost too much.

Since you have things apart, how will you align the clutch disk when you bolt the clutch assembly/ring gear back on? You can buy a plastic splined rod to do the job (not expensive) or just use a wood dowel that is roughly the same size as the ID of the pilot bearing/clutch plate to do the aligning.

Walt Fricke (who tends to leave the tranny in the car, but agrees that for you pulling everything was safer and less of a headache - plus you get to examine two of your CVs)

[kodioneill]

Just for future reference the proper method to drop the engine using a lift is to lower the car down to about two feet put jack under engine tranny connection point. take out mount bolts and raise the car while the engine stay's on the floor.
Installation is the reverse.

[Gunter]

Larry,

Didn't know you had a hoist.
That's almost like cheating.

With a hoist, we used a sturdy tea wagon made from steel on wheels.
Raise the car, disconnect lines and hoses, loosen the mounting bolts, lower the car onto the wagon so the engine/transmission rests on the heater boxes, remove the mounting bolts, raise the car and roll out the wagon.

Now you have everything on a comfortable height to work on.
Seperate the transmission, work on the clutch, etc.

To install, do the reverse.

Flywheel: I would put a dial indicator on it to see if it's distorted or has excessive run-out.
It may need to be reground if there are tiny cracks in the hot-spots.

If you remove it, you'll need the 12-point Allen (12mm?)
For street-driving, I'd re-use the stretch bolts.

I would not keep a rubber center disk, it may look good but.......................
Carefully check the pilot bearing, pressure plate, release bearing, fork, and that the bushings in the cross-shaft are good and lubed...............
This is the time to replace the seal for the shift-shaft in the 915.

[lr172]

Thanks for the advise here. It is a 4 post lift that has drive on ramps, not a more standard 2-post lift. It is designed more for storage than access, althought it does an ok job for that. The gap between the ramps is not wide enouh to clear the engine and it is difficult to get a floor jack on a cross beam.

Engine is an '88 3.2 with the G-50. What are the problems with the rubber centered clutches? Do they separate or just perform poorly? I can't say I am surprised to find this, as that cutch engagement always felt vague.

I would be afraid to put in a new disk with the same old P Plate. Not sure if I can have that machined or not. Also, can that flywheel be turned? The Bentlely manual said that it could not (the G-50 version only). I don't know if this is because it is thin or because it has an outer ridge that would prevent anything but a lathe from turning it.

Any one have experience here? My tendency is to throw it all back and deal with it later. It wasn't that hard to drop the engine and I suspect it will go twice as fast the second time. Somewhere in the next year I will be doing a top end and also want to consider stronger clutch options, as my turbo upgrade project should be getting me closer to 350 HP shortly.

Walt, I can usually eyeball align the disk pretty well. However, this may be tougher for me, as loosing the bolt on the plate don't necessarily release the spring pressure. It seemed like the P Plate was an interference fit. I may try to fabricate a dowel, as you suggest.

Thanks for the tips guys.

[Walt Fricke]

If it is worth it, a pressure plate can be flame sprayed and then machined. Usually it is not worth it, and simpler just to purchase a new one if the old one is bad. I did this because I have an aluminum pressure plate (RSR), which comes with something ferrous sprayed on. So it was worth getting fixed.

I'm not sure why a new clutch disk won't work with an old flywheel and pressure plate. Sure, shops like to replace everything, as that way nothing can go wrong for sure. However, if your old disk has some life left in it, and the engine is coming out again anyway, sounds like just putting it back is the way to go. One's perspective can change when you get comfortable with dropping the engine.

Rubber centered disks had a habit of coming apart. The first version, I believe, literally did that. Later ones had the rubber captured, so if it failed you still had a connection. But either way, rubber bits would escape and get caught between pressure surfaces. Which meant you couldn't get things fully disengaged, as the rubber caused quite a drag. Not too bad to shift when driving, but when stopped was an issue. You might consider this when replacing this stuff in the future.

Perhaps by the time of the G50 Porsche had resolved this? I'm a track guy, so I'd never consider rubber in this application. Plenty of vibrations and whatnot from all the gofasts.

Walt