Mission creep?

[FireTumbleweed]

Been about 6 months since I've been under my car and the oil leak that popped up a couple of months ago can't be ignored anymore. It's been a pretty leak free car for 200K+ miles so I can't really complain. Here's what I see; there is wet oil around the bottom of the bellhousing and slightly damp oil on the right side of the oil pan. The oil pan has been like that for about 2+years, usually just gave it a wipe down, never dripped. I'm pretty sure it's the rear main seal. I looked around to see what else I could put in my order and found a few things. My question to all is based upon the following that needs to be repaired what would the course of action be.

Replace clutch (original)
Replace rear main seal.
Replace Oil pan gasket.
Rebuild shifter mechanism
Replace swaybar links (Both replaced 2017 by me, Lemforder, boots are cracked)
Replace left Steering rack boot (Replaced 2017 by me, Lemforder Split in 2)
Replace under intake cooling pipes (Original, still don't leak!)
Repair rear CV joint (has been flinging minuscule grease for years)
R/I guibo (original) Note: Drivetrain makes no noise, feels tight and from attempted visual inspection looks ok

So do I....

1) Remove the intake manifold (in preparation of replacing the coolant pipes) and have all of it out of the way for additional work. (Access for upper bellhousing bolts improved?)
2) Pull the front clip off/radiator support and pull the engine/trans together and then take care of everything
3) Leave the engine in place, pull the transmission, then drop the subframe so I can replace the oil pan gasket after installing the rear main seal (and cover) like it was done in the factory.
4) Treat the coolant pipe replacement as completely separate from everything else.
5) Ignore the oil pan gasket for now since I wouldn't be duplicating work if I replace it in the future?

I guess what I'm asking is the up front difficulty of pulling the engine/trans out worth the ease of working on everything when it's easily accessible. If not what would be the best order to accomplish the repairs.

Addl: I thought I read somewhere that dropping the subframe while the transmission is removed is risky. Not sure where or why.

[CPHES]

Dropping rhe subframe while trans is out - is risky. When attached to the trans, the trans mount at the back is the pivot and balance. With it removed, the engine is not a balanced unit. Pulling the sub from below is going to be tricky. In a DIY world, I would caution against that.

[FireTumbleweed]

Thanks I knew I had seen it somewhere before. Your comment

Pulling the sub from below is going to be tricky.

Not sure if that is in ref to w/tranny removed or generally. If the transmission is removed, would lifting the engine be the way to go? i.e Would there be enough room to install the gasket? That would allow me to inspect the engine mounts I guess. Not sure what condition they are in.

creep...creep...creep....

[pleiades]

Be sure that the oil leak isn't from the valve cover gasket, particularly the right-rear corner. A slow drip from there will work its way down along the rear edge of the block/bell housing and when driving, the wind flowing under the car will spread it around, even forward.

[CPHES]

Pulling the subframe is not tricky. Supporting the engine correctly - when there is no transmission is harder. I don’t know what your skill and experience level is.

I would leave the trans attached, support the engine from above - either with a beam across the strut towers, and hooked to the right attachment points, or with a correct engine lift.

Do that work, and test to see if you are ok. Then pull transmission.

But, it all really depends on your skill level, tools available, and time. Having a second person to help is also useful.

[ross1]

You're in California? No rusty exhaust to deal with? That's a no brainer for me.
Take the engine and trans together. So much easier to then do all that service. I suggest that you re-gasket the whole works including external seals on the trans., all nickel/dime parts that will be very labor intensive to do later while in situ.

[FireTumbleweed]

Be sure that the oil leak isn't from the valve cover gasket

Been checked, there's no oil signs above the belt line of the oil pan gasket.

That's a no brainer for me.

Yea, I like the ease of working on it while it everything exposed, just hesitant of the removal. Skill/tools/time are all in my favor (except the engine hoist). I've done all before on various vehicles.

That being said, if/when I acquire a hoist and after removing the transmission (I own a trans jack) is it possible to lift the engine high enough without dc too many things in order to get the oil pan out from over the subframe? (I think the hiccup will be the ac lines). I'd pull the intake manifold (for coolant line replacement) and remove the radiator prior but like to keep as much connected as possible. It would save me from removing the front clip or dropping the subframe.

I suggest that you re-gasket the whole works including external seals on the trans.

Everything I can think of is in my cart, those that I don't use will be returned to FCP. I'm even ordering some of the metal parts for the shifter mechanism in case something is damaged during the repair. Since I have to warranty back the sway bar links, might as well use the box for the non-used items.

[ross1]

Been checked, there's no oil signs above the belt line of the oil pan gasket.



Yea, I like the ease of working on it while it everything exposed, just hesitant of the removal. Skill/tools/time are all in my favor (except the engine hoist). I've done all before on various vehicles.

That being said, if/when I acquire a hoist and after removing the transmission (I own a trans jack) is it possible to lift the engine high enough without dc too many things in order to get the oil pan out from over the subframe? (I think the hiccup will be the ac lines). I'd pull the intake manifold (for coolant line replacement) and remove the radiator prior but like to keep as much connected as possible. It would save me from removing the front clip or dropping the subframe.



Everything I can think of is in my cart, those that I don't use will be returned to FCP. I'm even ordering some of the metal parts for the shifter mechanism in case something is damaged during the repair. Since I have to warranty back the sway bar links, might as well use the box for the non-used items.

When I do it I disconnect the compressor from the engine and leave the lines attached. Can't speak to how much you might need to lift it for pan removal. If I lift it at all its coming out. IMO easier to take trans with the motor too, far less under the car time.

[FireTumbleweed]

OK...I took the easy (?) way out and decided to just pull the transmission and leave the engine in. Everything went very smoothly, pretty easy and quickly. I used a transmission jack when removing the exhaust. The DS came out no problems. Was able to remove all 10 transmission bolts (though don't know how I'm going to torque some of them). Pulled on the transmission to separate it, came about 3/4" and then stopped. It's hitting something up in the area of the starter. A definite solid metal in solid metal. It's not hitting the sway bar or the top of the transmission tunnel. I'm still planning on removing the intake manifold to do the coolant pipes which I'm guessing will give me easy access to whatever is stopping tranny from being removed.

That being said, anybody have any ideas? The transmission pulls smoothly about 3/4" then just stops. I noticed as I put it back together for the night (wife/assistant had to leave for a trip), the transmission housing had rotated about 1/2"-1". I didn't notice that when pulling on it. Is there a something on the starter that might catch the bell housing?

[pleiades]

OK...I took the easy (?) way out and decided to just pull the transmission and leave the engine in. Everything went very smoothly, pretty easy and quickly. I used a transmission jack when removing the exhaust. The DS came out no problems. Was able to remove all 10 transmission bolts (though don't know how I'm going to torque some of them). Pulled on the transmission to separate it, came about 3/4" and then stopped. It's hitting something up in the area of the starter. A definite solid metal in solid metal. It's not hitting the sway bar or the top of the transmission tunnel. I'm still planning on removing the intake manifold to do the coolant pipes which I'm guessing will give me easy access to whatever is stopping tranny from being removed.

That being said, anybody have any ideas? The transmission pulls smoothly about 3/4" then just stops. I noticed as I put it back together for the night (wife/assistant had to leave for a trip), the transmission housing had rotated about 1/2"-1". I didn't notice that when pulling on it. Is there a something on the starter that might catch the bell housing?

There's a small metal dowel piece for the starter that gets corroded and creates trouble in situations like this. Try removing the starter from above. If your intake manifold is already off, it's that much easier to get to. When I removed my trans to replace the clutch etc., I made a couple of headless long bolts with the same metric thread (purchased probably from local hardware store) so that the trans would have some guidance coming off/going back on. I slotted them with a dremel to be able to remove them with a flat-blade driver.

Trying to remember .... there's also a small bolt holding a bracket for the .... I think .... O2 harness, but the bolt is forward facing, and not visible from behind. Look for it on the right side of the bell housing.

[effduration]

+1 on the starter dowel pin

as Pleiades also said make sure you remove the forward facing 10mm that holds the shim to the bell housing. You access it from passenger side front of engine looking back towards transmission.

[FireTumbleweed]

pleiades was right. After removing the intake manifold it took me 5 minutes to wiggle/cajole the starter off the dowel pin.

Looking at the old throw-out bearing the part number on it supersedes (via realoem) to https://www.fcpeuro.com/products/bmw...ng-21517521471 which FCP lists as a BMW labeled part. However it looks and feels different from my old throwout bearing (it came with the Luk kit "OE"). FCP list Sachs as OE for the throw-out bearing and looking at the pictures of the Sach bearing (https://www.fcpeuro.com/products/bmw...ng-21517521471) it looks identical to my old part.

On the new "BMW" part, the actual metal flange that contacts the pressure plate also has a give/wobble in it, the old part does not.

20220501_130833_resized - Copy.jpg


So kinda confused, would Sachs (OE) continue to make the old part, yet provide an updated part to BMW and Luk (OE) to use in part of their kit? Or is the new "BMW" part sourced from a different manufacturer

[FireTumbleweed]

Been reading some threads regarding the replacement of the cooling pipes under the intake manifold. Just removed the old ones and am planning on installing the new ones tomorrow if time allows. In one thread it talked about pressure testing the system prior to reinstalling everything which sounds like a good idea. In the thread it was mentioned to remove the thermostat. Not sure why. Can anybody confirm that I should be able to pressure test the system without monkeying around with the thermostat?

As far as I know, the thermostat just prevents significant coolant from flowing, however there's still the back end that is open. Not sure why it was mentioned to remove the thermostat.

[effduration]

Been reading some threads regarding the replacement of the cooling pipes under the intake manifold. Just removed the old ones and am planning on installing the new ones tomorrow if time allows. In one thread it talked about pressure testing the system prior to reinstalling everything which sounds like a good idea. In the thread it was mentioned to remove the thermostat. Not sure why. Can anybody confirm that I should be able to pressure test the system without monkeying around with the thermostat?

As far as I know, the thermostat just prevents significant coolant from flowing, however there's still the back end that is open. Not sure why it was mentioned to remove the thermostat.

I think I made this suggestion

I have done coolant pipes 10+ times...Always uses Genuine BMW pipes...too many pblms with aftermarket pipes

Even with good pipes, clean holes, and silicone grease on o-rings, I will occasionally roll one of the two o-rings on the coolant pipes. Once installed, you can't see if it's rolled, particularly if its the inner one.

I test the pipes before I put the intake back on. This is how:

• take an old thermostat and remove the insides with pliers (squeeze tabs)- the metal thermostat part..leaving just the empty housing and heater probe
• install the gutted thermostat and hook up all the cooling pipes/hoses
• fill with distilled water - don't bother bleeding
• pressurize with 20 psi (no more). I do this with air fitting adapter screwed into bleed hole
• Look for leaks where coolant pipes enter cylinder head and block

I use a gutted thermostat for this because it allows coolant and air to move freely thru system for testing. You could also turn key to position #1 , turn heat up to 90 and red dots to force the stock thermostat open, but I usually have power disconnected, so I don't do this.

This has saved me from having to pull intake twice several times.

[FireTumbleweed]

I've got the OE (BMW) pipes from FCP since I do not want to do this again and some silicone grease at the ready . The holes had some degradation in them not a lot, smoothed them out with some fine emery paper.

RE: the thermostat. Again, not sure why you need to do this. As far as I know, there is not a one way valve that would prevent "pressure" from building in the entire system if the thermostat was closed. It just blocks flow. Or am I missing something?

I'd just rather not open up the housing and source another thermostat if I don't have to (it was replace about 5 years ago). I guess I could try and pressurize the system before reinstalling the pipes to see if I get air coming through, and if so that would confirm it should pressurize regardless of the thermostat.

[effduration]

.....

RE: the thermostat. Again, not sure why you need to do this. As far as I know, there is not a one way valve that would prevent "pressure" from building in the entire system if the thermostat was closed. It just blocks flow. Or am I missing something?

I'd just rather not open up the housing and source another thermostat if I don't have to (it was replace about 5 years ago). I guess I could try and pressurize the system before reinstalling the pipes to see if I get air coming through, and if so that would confirm it should pressurize regardless of the thermostat.

Fair enough...so is a thermostat water tight and not air tight in the closed position? Or is it neither water tight nor air tight? Maybe it just obstructs flow.

I do like seeing fluid (distilled water or coolant ) under pressure when testing these pipes. If it is just compressed air (remember you have drained most of the cooling system when you replace the pipes), A leak might not be as apparent.

Please give it a try with a good thermostat and let us know...


Edit: After looking at it, it appears to me that the Thermostat is water tight when in the closed position. However, the thermostat valve is on the inlet side coming from the lower radiator hose. Since I add pressure to the OUTLET side, via the bleed screw, the pressure probably makes its way to the coolant pipes even if the thermostat is closed. I am not 100% on this, but close...

[FireTumbleweed]

To follow up on this thread.... I wound up refilling the cooling system and pressurizing it with a tester from AZ, left it overnight no leaks! Yea.

Ross1, in the grand scheme of things if I had to do it all over again, I probably would remove the engine/tranny together. I have a set of quickjacks which made it pretty easy going under there and working. I did some detailing of the engine and that would have been a lot easier with it removed. I would have had to source a hoist but still. I have a transmission jack and aside from making the removal/installation of transmission easier, I also used it on the subframe and the exhaust system. That made working on those pretty easy.

CPHES, I dropped the subframe after reattaching the transmission, I agree after supporting the engine with the brace I think without the trans connected it would be pretty sketchy.

pleiades, I replaced a few of the corroded transmission bolts and used the couple of the old ones as alignment pins. That's a good trick!

The only hiccup I had when all was done was the car through a couple of TB codes. Came to find out, of all the connections involved I forgot to snap in the TB cable... doh! Couldn't wrangle my hand down there, so off came some parts again. No codes after that...

Now the only thing I notice is the clutch seems to engage a lot lower than I am used to. But I am guessing that is because the old one was so worn out. 210K original miles. It sure is a lot smoother and quieter.