zero 1162 Report post Posted January 12, 2016 I was driving along today when I saw the temp gauge at the nearly three quarters mark, luckily I was right near my destination so pulled straight into the driveway. I stopped the motor, but kept the fan going and put the heater on full hot. Oil was pouring past the radiator (!) cap and all over the engine and the driveway. sorry my cellphone pics are so bad; Car is my 2004 e46 wagon with the n46 (I know, I know) motor and auto trans which has done about 135k. Just prior to me buying the car two years ago the engine oil cooler was replaced under warranty. I've maintained it well (much better than the previous owner), with new ccv, new seals and orings, new radiator and tank, new waterpump, new spark plugs and belts, new hoses, rebuilt the vacuum pump, cleaned the thottle body and maf, regular oil changes with castrol edge 5w30 etc. Any ideas? Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted January 12, 2016 They leak oil & water..... now they are starting to make icecream 10 Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted January 12, 2016 Seriously though...going by the colour I'd say trans cooler... which would be a trans overhaul as well if it is. Fyber clutch plates in autos don't like hot water 1 Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted January 12, 2016 (edited) Whoa, sorry to see that dude. Can transmission fluid actually leak into the coolant Glenn? Of course I don't know how these systems work but didn't think these systems were in any way linked. My first guess was emulsified oil, it could be that colour but I wouldn't think that consistency. What does it look like under the oil cap and on dipstick? Hopefully not that colour! Edited January 12, 2016 by M3AN 2 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 Dipstick is clean, and looking through the oil cap hole is clean, oil cap had a little bit of mayonaise on it. Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted January 12, 2016 Dipstick is clean, and looking through the oil cap hole is clean, oil cap had a little bit of mayonaise on it. Well, you need to listen to Glenn before me! But if there's mayo on the cap and mayo in the radiator, if I hadn't seen Glenn's comment, my guess would be head gasket gone in a big, big way to cause that. 3 Quote Share this post Link to post Share on other sites
gjm 3258 Report post Posted January 12, 2016 Head gasket was my first guess, too, but the consistency of the leaked fluid is just too good. Even emulsified oil tends to be a bit lumpy - mayo, as Nathan says - and not like paint. I could have a quick look in a half hour or so, if that would help? 1 Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted January 12, 2016 Whoa, sorry to see that dude. Can transmission fluid actually leak into the coolant Glenn? Of course I don't know how these systems work but didn't think these systems were in any way linked. My first guess was emulsified oil, it could be that colour but I wouldn't think that consistency. What does it look like under the oil cap and on dipstick? Hopefully not that colour! Trans cooler on most cars is just a pipe running inside the bottom/side tank of the radiator with trans fluid running through it. If it leaks, trans oil and coolant will make babies. Im guessing the trans doesnt have a dipstick? stupid lifetime oil. 3 Quote Share this post Link to post Share on other sites
polley 916 Report post Posted January 12, 2016 I'm with glenn, trans cooler. 2 Quote Share this post Link to post Share on other sites
_ethrty-Andy_ 2132 Report post Posted January 12, 2016 if it is the trans cooler built into radiator like some earlier cars then can happen to any automatic BMW, not necessarily caused by being an N46 engine.... 2 Quote Share this post Link to post Share on other sites
gjm 3258 Report post Posted January 12, 2016 if it is the trans cooler built into radiator like some earlier cars then can happen to any automatic BMW, not necessarily caused by being an N46 engine.... You can prolong the interval between this happening with regular coolant changes. Sadly it is possibly one of those "it'll happen eventually" problems. Nathan - I did pop 'round this arvo but I think you were out. 1 Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted January 12, 2016 yeah, its actually not a great idea and they fail regularly on most makes. We just finished a customers Merc E500 that needed a trans rebuild because coolant contaminated the trans oil. Ended up running an external cooler instead of in the rad so it didnt happen again. It wasnt a disgustingly spectacular looking milkshake though. 2 Quote Share this post Link to post Share on other sites
gjm 3258 Report post Posted January 12, 2016 Ended up running an external cooler instead of in the rad so it didnt happen again. It wasnt a disgustingly spectacular looking milkshake though. Much better idea and a good mod if folk can be bothered. Removes the possibility of this issue (if not the possibility of leaks). 1 Quote Share this post Link to post Share on other sites
allan 295 Report post Posted January 12, 2016 (edited) All that love and care an it still goes and does the dirty is this any help http://bmwfans.info/parts-catalog/E46-Touring/Europe/318i-N46/apr2004/browse/radiator/oil_cooling_automatic_gearbox_a5s_r/ this is going to hurt $$$ wise no matter what. Depending on what is found maybe a manual conversion and engine transplant could be a thought to compare dollar wise. Edited January 12, 2016 by tim 325 1 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 Thanks for everyones concern - its been a pretty sh*t day to be honest. I spoke to Glenn just after it happened, and if it is trans cooler, then the transmission will eventually fail anyway from having water in it. I have a m54b25 and auto in my parts car (also a e46 wagon) - wondering if its better to swap this in than mucking about with transmission etc? I rebuilt an n46 cylinder head, ready to swap with my current one which has worn valve stem seals, but if I have to swap transmissions too, it doesnt feel like its worth the extra hassle/expense. Can anyone say how easy/hard and cheap/expensive it is to swap the m54 into a car that originally had an n46? I have all the parts in the parts car, except for some of the loom - do i need to swap looms too, or just add to what is in the n46 car? Just weighing up my options at the moment. Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 Well, you need to listen to Glenn before me! But if there's mayo on the cap and mayo in the radiator, if I hadn't seen Glenn's comment, my guess would be head gasket gone in a big, big way to cause that. The mayo on the oil cap and in the radiator look different to me. I think they are different substances but I'm no mechanic. Car is not driven hard at all, and wasnt when it happened, but of course all possibilities have to be investigated, so thanks for the head gasket suggestion. Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 Trans cooler on most cars is just a pipe running inside the bottom/side tank of the radiator with trans fluid running through it. If it leaks, trans oil and coolant will make babies. Im guessing the trans doesnt have a dipstick? stupid lifetime oil. Yea, no dipstick on the trans. I was going to replace the fluid this year anyways as part of preventative maintenance, but never got that far. Quote Share this post Link to post Share on other sites
gjm 3258 Report post Posted January 12, 2016 Thanks for everyones concern - its been a pretty sh*t day to be honest. I spoke to Glenn just after it happened, and if it is trans cooler, then the transmission will eventually fail anyway from having water in it. I have a m54b25 and auto in my parts car (also a e46 wagon) - wondering if its better to swap this in than mucking about with transmission etc? I rebuilt an n46 cylinder head, ready to swap with my current one which has worn valve stem seals, but if I have to swap transmissions too, it doesnt feel like its worth the extra hassle/expense. Can anyone say how easy/hard and cheap/expensive it is to swap the m54 into a car that originally had an n46? I have all the parts in the parts car, except for some of the loom - do i need to swap looms too, or just add to what is in the n46 car? Just weighing up my options at the moment. You have a big BBQ, with lots of beer, and invite a carefully selected group of people to bring their toolboxes and cranes over. Probably best to check it's a viable swap first... Sorry, I have no idea about that bit, or what (specifically) would be involved. 1 Quote Share this post Link to post Share on other sites
Ahmedsinc 414 Report post Posted January 12, 2016 (edited) If you have a parts mule to steal from I'd do the conversion. You will need to get it certed as it's a greater than 20% power increase AND you're increasing the displacement. Cert should be straightforward as you've got all the OEM parts at hand for the exchange, will probably have to install driveshaft hoops though. Not 100% sure as you'll have an OEM non modified DS but best to speak with an inspector directly. Full engine, loom, dash, EWS, TCM and trans plumbing to go from a - b. Diff too, not sure if the subframes are different between the small case & medium case types on E46? Maybe bigger brakes from the 325i as well, if applicable? I'm not savvy with E46 rotor sizes except for the 330i stuff. It'll be a big job, but at least you'll have a driveline setup that will last longer than 146,000km. Sorry to see it happen to you but I can't say I'm surprised! Edit: for all the hassle involved why not go to the M54B30 & a manual box? Not exactly cheap but the benefits would be worth the effort Edited January 12, 2016 by Ahmedsinc Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted January 12, 2016 imo unless youre really attached to the car, it would be best to grab a replacement auto from hellbm or brent, install that and either run the car as is, or sell it and get something M54B30 powered. It just wouldnt be worth the cost, effort and work to convert it. 2 Quote Share this post Link to post Share on other sites
Ahmedsinc 414 Report post Posted January 12, 2016 imo unless youre really attached to the car, it would be best to grab a replacement auto from hellbm or brent, install that and either run the car as is, or sell it and get something M54B30 powered. It just wouldnt be worth the cost, effort and work to convert it. Not a hell of a lot of B30 wagons around, but you're dead right on the cost scale. If he can do the B25 conversion for minimal outlay it'd be a damn sight better than another N46 thats only going to grenade itself in short order 2 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 If you have a parts mule to steal from I'd do the conversion. You will need to get it certed as it's a greater than 20% power increase AND you're increasing the displacement. Cert should be straightforward as you've got all the OEM parts at hand for the exchange, will probably have to install driveshaft hoops though. Not 100% sure as you'll have an OEM non modified DS but best to speak with an inspector directly. Full engine, loom, dash, EWS, TCM and trans plumbing to go from a - b. Diff too, not sure if the subframes are different between the small case & medium case types on E46? Maybe bigger brakes from the 325i as well, if applicable? I'm not savvy with E46 rotor sizes except for the 330i stuff. It'll be a big job, but at least you'll have a driveline setup that will last longer than 146,000km. Sorry to see it happen to you but I can't say I'm surprised! Edit: for all the hassle involved why not go to the M54B30 & a manual box? Not exactly cheap but the benefits would be worth the effort Thanks. Cant go manual as wife can only drive an auto. I would love to go m54b30 but just cant afford to buy another engine. The brakes are identical on both cars, as is the rear axle carrier. I think the diffs are the same except for the ratio? Here is the realoem on both cars; My 2004 318i black wagon; http://www.realoem.com/bmw/enUS/select?vin=PR00173 2001 325i parts wagon; http://www.realoem.com/bmw/enUS/select?vin=eg15996 1 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 imo unless youre really attached to the car, it would be best to grab a replacement auto from hellbm or brent, install that and either run the car as is, or sell it and get something M54B30 powered. It just wouldnt be worth the cost, effort and work to convert it. My parts car has the same trans cooler if I go that route - then I just need to buy and swap the transmissions. Quote Share this post Link to post Share on other sites
Ahmedsinc 414 Report post Posted January 12, 2016 Thanks. Cant go manual as wife can only drive an auto. I would love to go m54b30 but just cant afford to buy another engine. The brakes are identical on both cars, as is the rear axle carrier. I think the diffs are the same except for the ratio? Here is the realoem on both cars; My 2004 318i black wagon; http://www.realoem.com/bmw/enUS/select?vin=PR00173 2001 325i parts wagon; http://www.realoem.com/bmw/enUS/select?vin=eg15996 Well that will make it easier then. Im accustomed to E36s where theres a difference between the diff carriers. My parts car has the same trans cooler if I go that route - then I just need to buy and swap the transmissions. You don't already have the trans? Need to factor that into the budget, plus the cost of the TCM and any required wiring. Pretty confident that the looms will not be interchangeable. Whats the car worth as a parts mule? Might yet be more cost effective to cut your losses and get something less inclined to commit suicide on your drive home from work? 1 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 12, 2016 You don't already have the trans? Need to factor that into the budget, plus the cost of the TCM and any required wiring. Pretty confident that the looms will not be interchangeable. Whats the car worth as a parts mule? Might yet be more cost effective to cut your losses and get something less inclined to commit suicide on your drive home from work? I have the trans in the parts car connected to the m54b25, but the n46b20 engine uses a different trans. If I simply just swap out the trans on my car (no engine conversion) then I need to buy a trans. I dont need to buy another trans cooler though, as I can steal the one off the parts car. I will have to remove and clean so many parts on my n46 as the sludge will be everywhere. I will have to put a radiator flush through too, to get all the sludge out of the water galleys in the engine. Quote Share this post Link to post Share on other sites
