Rookie Engine Drop & Reseal, G50 Carrera Cab

[COLB]

I know there are a stack of these, but one more can't hurt!

Post #1: Background

This is my car:



She is a 1988 911 Carrera Cabriolet, Silver with Burgundy interior. I bought the car about 18 months ago after a six month search -- initially looking to buy another (cheaper) Boxster to replace the 987 I sold the year prior. I had been thinking about older 911s since I first started shopping Porsche options in 2008.

I got this car through a craigslist ad in Northern Virginia. A two owner car with 80k miles, it was in very good cosmetic condition, and pretty well maintained. The service books had dealer stamps for the first few years, then a gap, and the all the records from the second owner starting in 2005. It had a healthy compression test, and a PPI when I bought it -- with minor flaws fixed for a few hundred: new fuel pressure reg, rebuilt AFM, O2 sensor, oil change, and a few other nits.

Apart from a head unit, the car is all original. It runs great, the clutch is sound, the brakes have less than 10k miles (I rebuilt the front calipers.) I knew about the valve guide issue going in, but given the solid PPI and healthy compression, I thought the risk was acceptable given the good price.

Since purchase, I have rebuilt the front calipers, had an upholstery shop install a new convertible top, and have done a quickie R-134 conversion to get the A/C working (to some extent).

Now, 18 months and 5k miles later, it does not exhibit any smoking, but the engine has averaged a quart "used" every 500-600 miles -- at the edge of "OK" for an unrebuilt engine with 85k.

I say used, because it is also developed some leaks. There is a pretty significant leak from the back of the engine, which drips onto the crossover pipe and burns without hitting the floor:



I changed the oil pressure sender when I bought the car, but the breather gasket and thermostat O-ring are likely culprits. Maybe the oil cooler seals, too?

It also leaks from the driver's side cam oil line:



and this is puddling a bit, dripping oil down the front of the engine, onto the heat exchanger, and spotting the garage floor:



Given that an oil change and valve adjustment are due, and looking at the volume of oil leakage, I've decided to drop the motor, fix the oil leaks, clean the case, transmission, and engine bay, replace the gear oil, adjust the valves, and then do a leakdown test.

In addition to building my newbie wrench skills and gaining familiarity with the car, it will give me a good sense of the engine's health without overtaxing my meager mechanical skills.

If the leakdown doesn't show any horrific results, I will fix, clean, reassamble, and then drive it for another year and continue to monitor oil use. If it stays in the 500-600 range, I will start saving for a top end.

After dropping the engine once, I will be much better prepared to DIY at least the basic parts, and bend down the cost to a level less likely to cause the wife to stroke out. Or smother me in my sleep. Next Post: The Prep

[COLB]

Post #2: The Prep.

I have read a number of threads, and have both Wayne's 101 Projects and the Bentley Manual. I have found the Bentley manual to be a little better, because it is specific to my car, while the pictures in Wayne's book are SCs -- and for newbs that can be a challenge.

For supplies, I placed a pretty significant order with our host:



- Valve Cover Gaskets (with silicon bead for lowers)
- Left and Right Cam Oil lines
- Breather gasket
- Oil Thermostat Gasket
- Cylinder Head Temperature Sensor ( it surges a little when cold starting)
- Oil Cooler Seals (I got the three green ones; I guess some think the brown are the thing?)
- Oil Tank "S" hose
- Valve clearance tool & extra blades
- Mahle Fuel ad Oil Filters
- appropriate crush washers for the drain plugs & oil lines.

I also got a few extra bits for later: new rear seatbelt plastic holders, and a A/C pressure regulator for when I take on the A/C again this spring.

I picked up 13 quarts of Valvoline VR-1 Racing oil, and will be using Mobil 1 DELVAC gear oil if I can source it locally.

I located a local shop that can rebuild my high pressure fuel hoses, and will get those redone "while I am in there". Other than that, I am trying to keep expenses down.

From Harbor Freight, I got a Leakdown Test set, and a furniture dolly, which I rebuilt with 2x4s and plywood to make an engine cart:



I feel like I need some additional wod to make sure the "right" part of the case is support, and I don't mash the exhaust. But I see people laying them flat on carts, so I guess this will work.

The plan was to jack up the rear, disconnect everything, and raise the front to make it level -- lift the cart up on the floor jack til it supports the engine, disconnect the transmission and engine mounts, then drop it to the floor.

Then drop the front of the car back down to raise the rear bumper so I can roll it out. I know that is an extra step, but dropping it from a level car is less nerve wracking for a newb! Next Post: The Unconnecting

[COLB]

Post #3: The Unconnecting.

I am not going to go through every step, but will highlight a couple of screwups and difficulties in areas that the Bentley and 101 books leave pretty vague, especially for G50 cars.

Two weeks prior, since I was going to change the oil anyway, I put a bottle of Techron into a 1/4 tank of gas, and gave it a bit of an "Italian Tune-up" -- driving the car on several long rides, keeping up the RPM. I hope this might clear out some carbon that could be keeping the valves from closing all the way, which might affect the leakdown test.

The day I started, I drove it 30 minutes to get the oil to operating temperature. Here is the engine at the beginning. I hope I can get it all back together! Note the towels to protect the paint:



***First Mistake*** -- before starting, I should have immediately gone around the car and sprayed all the CV bolts and other difficult to remove nuts with PB Blaster. This would have made my life easier.

Jacking was simple, as was removing the A/C compressor to get it out of the way, and draining the oil:



Although the book doesn't mention it, I used a Sharpie to note the position of the bolts on the compressor mount, so when I reinstall it, the tension will be right:



The vacuum hoses were a bear to undo, the rest of the hoses and electrical connectors were pretty simple. I got to my first problem where the Bentley manual advises you to: "detach 14-Pin harness connector from panel."

That's cool, but it doesn't show a picture, or tell you HOW the connector "separates" from the panel. The connector appears to be in four pieces, with a tabbed back piece.

***Second Mistake***: I pry off the back piece rather than just pulling the two halves of the connector apart. Now the male connecter wires are loose, and only then does it become apparent that the bracket is just two halves that just pull apart, with no tabs or little wires holding them together.

It sounds intuitive now, but it wasn't when I was looking at the thing together. Now I have the thing apart, but the male side of the 14-pin connector is in two pieces, and the wires are slipping out of the holes. I try to squeeze it back together, and it shatters in my hand:



Irritating. I have broken my first piece. But it is doubly irritating when I discover the little plastic piece I broke costs $52 from our host.

***Third Mistake***: when disconnecting the Speedometer Sending Unit in the transmission tunnel, I can't really tell how it comes apart. I pull the first one apart ok. On the second one, the wire pulls out of the spade connector.

A new sender is $82 or 150, depending on the brand. I've heard from one source that the cheaper ones don't last. Does the board have any opinion?

I hope I can just recrimp the wire back on the spade connector since the sending unit was work fine before.

The next trouble spot: The Cruise Control. The Bentley manual directs disconnecting the cruise control cable from a tube like "vacuum module". But my 1988 car doesn't have anything like that. Instead, after a period of frustration, I realize it looks like this:



And the book doesn't address how to remove the cable, nor is it intuitive.

To take it apart, I removed the three visible bolts holding the metal frame down, then pulled out the whole piece. Then you can see how the cruise cable is mounted and unhook it, then remove it from the frame by compressing the tabs on the black plastic grommet that holds it in place.



I set the gold frame to the side with the other removed parts and left the cable attached to the engine, as it is still mounted to the throttle. There are two crosstip screws that you could remove to separate it from the throttle, but they are tight and soft, and I started to strip them trying to unscrew them. So I just left it there.

Under the car to disconnect the CV joints. I used a 8mm hex socket on a 3/8 inch ratchet, with a cheater pipe for leverage. Only now do I think about soaking them with PB Blaster, which COULD have been working for several hours at this point.

I start with the driver side, and although it is difficult, I get them loose. I position one at the 9 o'clock position so I can fit the socket on against the CV boot, have my son set the parking brake, crack the bolt, release the brake, rotate the tire to position the next bolt. Repeat. Painful, but it gets done.

Next, I move to the passenger side, and repeat the same procedure, setting up the same way. But instead of cracking, I can't get the first one loose. I'm pulling down so hard on the cheater pipe I am afraid I am either going to pull something, or break off the head. So I spray some PB Blaster, and try the next one. Some thing. It moves a tiny bit. More PB, try next one. One the next two, I partially strip out the bolts. By now I've been at it 8 hours, and am pissed and beat.

So I spray them all, and quit for the night, and try to get some hints on Pelican. I order a Craftsman bolt remover tool set from Amazon that several people recommended, then I go to sleep.

Of course I can't sleep, thinking about the nightmare of getting out 6 frozen CV bolts. Somewhere in the middle of the night, my sleeping brain suddenly realizes the problem, and I wake up recognizing my:

***Fourth Mistake***: when I changed to the other CV joint, I used the same method, even though the CV is a mirror image of the other side. By pulling down on the ratchet, I've been TIGHTENING the bolts, not loosening them. Now I want to shoot myself. Lefty loosey -- Righty Tighty, sportsfans.

Armed with this insight, I tackle the CV bolts the next day. The challenge is that they are now all extra torqued, and I can't generate enough leverage trying to left the cheater pipe under the car, on my back. So I improvise.

I positioedn the ratchet on the bolt at about a 45 degree angle, then used the floor jack to slowly crank up the ratchet and crack the bolt:



This worked like a charm, and I managed to get them all undone -- even the partially stripped ones.

Given that I probably overtorqued them, I am thinking about getting some replacements just in case. What do you think?

The last big bear was the slave cylinder. Some sources say take it out, others say leave it in, and just disconnect the hydraulic hose. I removed it, but it was painful. After removing the CV, I was able to snake one arm up to it, and find the bolts by feel. I used a 13mm short socket on a 1/4 inch mini ratchet. A ratcheting box wrench would probably have worked better, but I don't have any.

As it currently stands, I think I have everything disconnected, and ready for the moment of truth.

We have a snow day tomorrow, so I will probably get my neighbor to help me. I will double check all the connections (I'm not sure I got the starter motor connection...where is that? Is it under the car?) And I need to check the coil, and the oil lines.

Then I will go to Post #4: The Drop.

I hope I'm done with any major mistakes!

Please give any last minute advice on often overlooked connections, or other problem areas.

[zippy_gg]

Originally Posted by COLB

Given that I probably overtorqued them, I am thinking about getting some replacements just in case. What do you think?

Do replace the partially rounded ones so you will be able to torque the drive shafts properly when you re-install them. If you don't your wrench will start slipping and your shafts won't be securely attached to the differential.
Also re-torque after 100 miles or so and you may find the bolts started to back out already.
Better safe than sorry!

[michael lang]

Good luck with the drop. I too find the Bentley manual more useful because it is more model specific than the 101 Projects although I refer to that from time to time.
It's hard to tell from the picture you posted or maybe it's the angle of the picture but it looks like you may not have raised up the rear enough to get the engine out, you have to remember that you will need atleast the extra height to compensate for the dolly once the engine is on the ground and need to roll it out.

[geoz]

Nice one, I'll be very interested how it goes. Mine does not leak but I'm sure I'll have to drop the engine at some stage.

Good luck.

[Dr J]

Good job. Hang in there. The cv joints are a pain indeed. Once had to air hammer one off. Just take plenty of pics to refer to when putting it back together. Also get baggies and label what you take off. You may also want to label wires and hoses that you disconnect. A little extra time now can save much grief later. Also get a torque wrench if you don't have one. Remember your jack on wrench technique as it may come useful to disconnect the hard oil line.

[COLB]

Originally Posted by Dr J

Good job. Hang in there. The cv joints are a pain indeed. Once had to air hammer one off. Just take plenty of pics to refer to when putting it back together. Also get baggies and label what you take off. You may also want to label wires and hoses that you disconnect. A little extra time now can save much grief later. Also get a torque wrench if you don't have one. Remember your jack on wrench technique as it may come useful to disconnect the hard oil line.

I used baggies & labeled everything, and also bought a torque wrench. Forgot to mention that.

Thanks for the tip on the hard oil line.

It's hard to tell from the picture you posted or maybe it's the angle of the picture but it looks like you may not have raised up the rear enough to get the engine out, you have to remember that you will need atleast the extra height to compensate for the dolly once the engine is on the ground and need to roll it out.

The dolly adds a couple of inches. I jacked the rear up to the full extent of my jack, so I am assuming that the rear bumper is going to have to come off to to get the engine out. Another fiddly step, but not sure I want to try to rig the jack to go higher.

[Hnichols]

Thanks for a great thread. I hope I'm able to find it when I do my first engine drop.

Hopefully you'll be able to address the oil leaks. Since the car doesn't smoke, and has only 80K, you might have a long time before you have to do a top end.

Have you considered replacing the clutch plate while you have everything out? You're probably on the original, and it will soon when you have to replace it anyway.

[jmills]

I just got my motor back in after very similar repairs. Make sure you keep a close eye on the front part of the transmission as you lower and remove the engine from the car. It's good to have a second person watch the access panel where the shifter coupler attaches from inside the car as you are lowering it to make sure it doesn't hang up. You won't be able to fully lower the motor until the nose of the transmission is free of the hole in the firewall.

Good luck!

[Flat6pac]

On a G50the nose of the trans is outside the firewall but make sure you are free of the aluminum unit that connects to the shifter as it is expensive to break.
Be sure you update the needle bearings in the tran bellhousing. I prefer the brass replacements over the drilling out the bosses to allow the new bearings room.
Bruce

[COLB]

Have you considered replacing the clutch plate while you have everything out? You're probably on the original, and it will soon when you have to replace it anyway.

I did think about it, but I am going to let sleeping dogs lie.

If I'd paid someone to drop the engine, it would make financial sense to do it while I'm "in there". But the clutch is strong, and I expect it has 20k miles or more left considering the way I drive it. I have to assume it is original, although it is possible it was changed by the first owner prior to 2005, where I have a record gap. The car appears to have been garaged its whole life, and generally the rubber and plastic has aged well. So I hope rubber center lasts toward the longer end of "average" life.

I may regret it later, but frankly I am not interested in dropping $900+ on a clutch job when it is not necessary. When I do it, it will be the full monty, with upgrades, needle bearings, pressure plate, etc.

On a G50the nose of the trans is outside the firewall but make sure you are free of the aluminum unit that connects to the shifter as it is expensive to break.

Tracking -- it was a bit of a chore to get the rod out of the shifter fitting, but I managed it. I will keep an eye out to make sure i back the nose out of the tunnel before lowering -- good tip.

[jmills]

COLB-you may have already stumbled across the tread that I recently did when I pulled the motor on my '84 Targa and fixed a lot of oil leaks. If you haven't, it might help you out. It sounds like you are doing a lot same repairs that I did. I had no prior experience with an older 911, so I know exactly where you are coming from.

You have already done the hard part....getting started.

First timer takes on '84 Targa

[Flat6pac]

The bolt that comes out of the nose shifter of the trans is specific for the job 8mm with long shoulder and 5 or 6 threads.

[jm13004]

Colb,
I'm subscribed. Thanks for the info you sent. I'll be following closely since we are almost doing the same exact maintenance . Your narrative and pics are awesome. The fact that your taking the time to post your project in detail is what makes this forum so great. I now know what you were talking about regarding the Bentley Manual description on the cruise control module. That's a big help.

I'm going to check my clutch...I don't think it will be that much more work plus I want to see if I have the upgrade. Keep at it, your doing a great job!

[rusnak]

maybe it's in here somewhere, but why are you dropping the engine?

It seems to me all the stuff in Post #1 can be done with the engine still in the car.

[COLB]

Originally Posted by rusnak

maybe it's in here somewhere, but why are you dropping the engine?

It seems to me all the stuff in Post #1 can be done with the engine still in the car.

It is seriously leaking from the breather gasket and oil thermostat. I read you can do those a partial drop, but not the oil cooler seals -- which I think are leaking as well.

It also needs the high pressure fuel lines replaced -- and I understand you have to take the manifold off if you want to do the "T-line" in the car.

I've also never done a valve adjustment, and I understand it is much easier to do with the engine out.

So when you total the jobs I want to do, the collective PITA factor of each probably makes it worth it to drop the engine. Then I can clean it more thoroughly and get a better read on the leaks.

The "plus" is learning a lot more about my car -- which is part of the fun of ownership.

After reading a bunch of clutch threads, I think I might at least separate the engine and trans and inspect the throw out bearing to see if it has been updated. I also read that a Porsche dealer can check if your VIN still has the clutch bearing recall outstanding --- although it could have been done at an independent and they wouldn't know. True?

If it has the new bearing, then I think it is very likely the clutch was replaced at the same time -- because it seems very sound given the age and mileage. If not, I will face a major decision point....

BTW -- I got the engine on the ground last night with no (apparent) damage! Details to follow later tonight. I need to get a 4x4 from Home Depot to let me jack the rear up higher. As it sits now, I can't get it out even with the bumper off.

[rusnak]

I certainly understand your logic, but the thought that comes to mind is that the oil leak would be normally addressed by replacing the thermostat and oil pressure switch first. If that does it, then you're better off waiting until you have a bit more experience IMHO, before tackling the engine drop, which although is not difficult, has many areas that someone who is inexperienced may struggle with and may also damage expensive parts.

The oil thermostat and oil pressure changeout is literally a 30 minute job. I'd have waited until you have also done a valve adjustment, brake service, wheel bearing replacement, etc - stuff like that before you take on this job.

I also agree that replacing the fuel lines and oil cooler seals are good preventative tasks, but it's not like you have to do that right now. If you do go ahead with the engine drop, then logical tasks would be to change the flexible brake lines in the rear, change the main crankshaft seal, clean and lube the TO bearing shaft and related bushings, replace the pilot bearing and seal, possibly replace the TO bearing, and inspect the clutch disc. The clutch disc should outlast the crank seal if the crank seal is replaced before it fails.

However there are a lot of things, that can go wrong in these jobs. It's just so much more than knowing how to loosen bolts correctly.

[COLB]

I also agree that replacing the fuel lines and oil cooler seals are good preventative tasks, but it's not like you have to do that right now. If you do go ahead with the engine drop, then logical tasks would be to change the flexible brake lines in the rear, change the main crankshaft seal, clean and lube the TO bearing shaft and related bushings, replace the pilot bearing and seal, possibly replace the TO bearing, and inspect the clutch disc.

Well, the engine is on the ground...too late to back out now!

[rusnak]

Haha! OK, well I'll do what I can to help you.