Hello again. Last we met was here: https://www.motoringalliance.com/threads/2004-r53-re-build-thread.31480/page-9 That thread ended with the car running well but leaking oil from a few known locations. Here I am a year later, thinking I'd solved those problems, but no. Since the big misfire thread, we replaced the oil cooler sealing gasket. Re-installing the oil cooler was the death of it, and it failed completely, dumping all 4.5 liters of oil in a one-mile drive. That was fun. But it has a new oil cooler now! The car is still leaking. There is so much oil spread around the back, bottom and front of the engine, and up the front of the transmission, that neither I or my mechanic can pinpoint a location for the leak. In addition to leaking, we think it's burning oil. Regardless of the causes of abnormal oil consumption, we have to add 4 liters of oil every 1,000 miles. Car is at 163,000 miles now. I know oil consumption increases, but that's really too much, right? So the question in the subject line is where I'm at. I see my future facing one of those three options. I put a lot of work into it a year ago, and there are a lot of new parts that I can re-use, but a lot of new gaskets that won't be reused if I do a rebuild. But if I remove the engine to rebuild it, access is no longer an obstacle and by doing most of that job for the second time, maybe I'll do it right (assuming rookie mistakes last year have led me to this point). Or, I can find a used engine replacement. Looks like decent examples are around $2300 to $2500 (looking at Allmag, not sure what other sources I could use). But to be honest that feels like far too much money to spend after the spendy journey I've been on just to be where it is now. Or, last night my son (this is his car) said he'd finally consider parting ways with it (but thinks he would buy an E30... sweet jesus what I have I done to this boy...) It's not like I can get money out of it at this point. Part of me (most if I'm honest) says pull the engine, rebuild it, and put it back together. If it's running then, either keep it as a fun distraction / track car or sell it for whatever I can get.
I guess I would add up the parts and machine shop cost then decide. The bottom end of first Gen cars are rock solid and very tuff. I guess the other variables would be do you want to do a rebuild with you son for the fun? And are you going back stock or doing some mods? I mean if you really want to go crazy you could get a RMW storker motor. Your son has really good taste! It’s hard to find a nice unmolested E30 these days but boy if you do what a great car! I traded in my 1987 E30 325i convertible for my first mini years ago. A 02 R53.
yeah i'm all over the place with how to think about it. Having never rebuilt an engine, I'm not sure why I think that's the solution to the constant oil leaking and high consumption. But it's not going to get any better by doing nothing either. At the very least I want to pull the front end off again and attempt to isolate where the leaking is coming from, I can't tell from under the car, it's just all over. if I get into it I'll be updating here for sure!
Well you rebuilt the head, that’s half the engine. Warm the motor up and do a compression check like be for, do it dry then wet. If you have good compression both dry and wet the bottom is good. What do the plugs look like? When I did the refresh on my R53 I tried to stop all the oil leaks. The list; oil housing rings/gaskets, new oil lines, new oil pan gasket, I had the transmission out to replace the clutch so I replaced the rear seal, crank position sensor seal and added red RTV for good measure, the front seal had been done about 2 years earlier so I did not do it, new power steering pump hoses and don’t use the Mini clamps, get some good ones, power steering reservoir, FIY it has a built in filter. When I was doing all that I broke a small t-fitting for the radiator and got to replace it. After all that a few months later I had a small oil leak. It may have been the oil dipstick tube. I use to own Italian cars so small oil leaks are comforting, Ha! When you did the head please tell me you replaced the valve stem seals, if not it could be the source of consumption.
I’ve done everything you did except: did not replace oil lines, and the transmission hasn’t been disconnected since the clutch was redone 7 years ago. So the rear main seal is 7 years / 65,000 miles old. Valve seals were done with the valve job 100% yes! any experience with the point in the front of the transmission where the slave cylinder goes in? That is either the leak or a source of leaking, or oil is wicking it’s way up to that area. I can’t tell which. That would be leaking transmission fluid not oil I guess. It’s a mess there at any rate. Maybe that’s what’s leaking and then wicking up the seams, and spreading across the bottom of the oil pan and onto the back of the engine.
No the only thing near there is the crank position sensor. If it’s the rear seal it will come out the bottom. My oil lines to the filter were very soft. Check yours if there soft get new ones
Agreed. That sensors o-ring is probably the culprit if there is a leak in that area Sent from my iPhone using Tapatalk
I might have time to get the front end off tomorrow and have a really good at everything. I replaced the CPS o ring last year, I’m sure it’s possible it’s leaking or has leaked ever since if I didn’t get it installed properly. But when I look up the front of the engine and transmission from underneath, there is a lot of fluid (oil or tranny fluid not sure) on and all around the rubber boot that covers the entry of the clutch slave cylinder where it enters the transmission. But I haven’t been able to see it clearly enough to tell if there is just oil collecting there that’s come from somewhere else if that point is leaking. I won’t be able to see it or get photos of it until I can pull the front off again.
Yea pictures really help. It’s the weekend you don’t have anything better to do the work on the Mini.
Pretty much feels like it! But as it turns out, won’t be getting into it this weekend. thinking we can make time for it over the next couple weeks though. So it goes. And goes.
If you have oil on backside of the motor and already changed the oil housing gasket, you might check the oil pressure sender. It will have a wire and connector going to it, however when they fail oil comes through the connector. It sits midway up on backside of block. Access is either from pass side wheel well or top of motor. If this is the problem, buy an oem one as the aftermarket typically don't work well (they leak when new).