Hello everyone, i just bought a 1992 BMW 325i convertible. They previous owner said it was overheating. I just replaced the thermostat and realized that the coolant was very rusty looking. I filled it up with water so i didnt waste coolant because i am going to have the radiator flushed. There is a little bit of water leaking from the front of the motor, it is splashing off the belt. There is white smoke billowing out of the exhaust. It wasn't doing this at all when i ran the car to find the leaks. I ran it quite a few times but the temperature never got much over the blue area on the guage each time. I ran it for a few minutes so i could check out the smoke, which of course doesnt smell like coolant because its full of water. I checked the guage and it was really hot, but not quite to the red yet. The car is also now running a little rougher than it was before. Do you think it is the head gasket? Any help is appreciated. Thanks in advance.
Last edited by lovinfishin9; 10-12-2008 at 08:25 PM.
sounds like headgasket to me
remove the 3-4 cyl plugs and use a flasjlight to look into the cyl. i bet you see coolant/water. you may have even cracked the head in the 3-4 cyl area. they are common to do that
+1, sounds like headgasket. Start the car with the radiator cap off, coolant full. Rev motor lightely, if necessary. If you wash the hoodliner, you need a headgasket.
Chris Powell
Racer and Instructor since, well. decades, ok?
Master Auto Tech, owner of German Motors of Aberdeen
BMWCCA 274412
German Motors is hiring ! https://www.bimmerforums.com/forum/s...1#post30831471
Yeah it does spew out of the radiator. Why does a bad head gasket cause it to come out of the radiator like that? Just curious.
pressure and hot gasses being vented from the cylinder into the cooling system
Sorry, lovinfishin, that confirms it. Someone decided to "make it home" after the needle said hot. Thank you, former owner.
Chris Powell
Racer and Instructor since, well. decades, ok?
Master Auto Tech, owner of German Motors of Aberdeen
BMWCCA 274412
German Motors is hiring ! https://www.bimmerforums.com/forum/s...1#post30831471
IDK how strapped for cash you are, but they make this liquid glass stuff that seals blown headgaskets. I have never used it in a bimmer, but it didwonders with my winter beater. Check it out, its this additive that you pour into the coolant and run till it gets hot,then you flush the coolant out and see if the leak is sealed. Repeat if necesary. Only do this if you absolutely cannot afford a head gasket fix.
1994 530iA
Alright im working on replacing the head gasket but the manual i have says to remove the vibration damper to remove the timing cover. How do i hold the crankshaft from turning to loosen the bolt. The book doesnt say.
And im going to replace the timing belt while im in there.
Good luck with that, M50's don't have belts inside. And be aware that if your head gasket is blown, your cylinder head is likely warped, possible cracked. Take the head to a machine shop, and have them check it over, and advise you. You need a Bentley manual, AT LEAST, for this job. You might need to replace the head bolts: any M50 guys wanna chime in?
Chris Powell
Racer and Instructor since, well. decades, ok?
Master Auto Tech, owner of German Motors of Aberdeen
BMWCCA 274412
German Motors is hiring ! https://www.bimmerforums.com/forum/s...1#post30831471
It is an M20 single overhead cam, so it has a timing belt. And i already planned to take it to the machine shop. Im gonna take it down tomorrow probably, i got the damper off.
Must be a convertible? I was picturing an E36, that's why I thought M50. Glad you found the smaller pulley bolts. While you're in there, do the water pump, you don't want to have to go back in. Crossed fingers for your head being ok.
Chris Powell
Racer and Instructor since, well. decades, ok?
Master Auto Tech, owner of German Motors of Aberdeen
BMWCCA 274412
German Motors is hiring ! https://www.bimmerforums.com/forum/s...1#post30831471
Yeah i was thinking about the water pump, and yes it is a convertible. And yeah my fingers are crossed too.
well i didnt get a chance to take the head to shop until today cause they were closed, then i had to go out of town. Its got a crack under the cam about 6-7 inches long across two cam journals. Anyone know where i can get a head for cheap, the shop quoted me $1000 for a rebuilt one.
Headgasket.
Check the water pump also, that could have been the source of the leak up front and all your troubles. Oh yeah, M20? Do the timing belt while you're in there.
If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower. - Mark Donohue
good news guys i found a rebuilt head with less than 100 miles on it for 80 bucks.
Alright, i've been in Pennsylvania for the last week, but i finally got the head done. With the head off i could see that all the coolant passages were gummed up from whatever the previous owner put in it. I want to completely flush the cooling system including the heater core, im pretty sure its clogged up too. Does anyone have a link or advice on how to do it.
I got it all flushed out. But I have a problem. White Smoke from the exhaust. And there is coolant spraying out where the timing cover meets the block on the passenger side. Oh yeah. it's not the same leak as before, that turned out to be a hose.
Last edited by lovinfishin9; 11-02-2008 at 05:19 PM.
Well i guess im just really aggravated and not thinking straight. Its spraying out where the water pump meets the block, time to tear it apart again.
In case you haven't figured out the white smoke, sounds like you could still have oil/coolant in your system...
This is one of those projects you need to take your time with!! I actually just rebuilt my M50 head on my '94 325is cause I had floated all 12 exhaust valves.. OUCH!
That being said, make sure you torque everything properly, seal everything properly, wait the allotted times during torquing... and don't even think about sneezing around the top end of your engine while you have it open - Crap in the oil/head could kill the whole project.. There's no such thing as too clean. Change your oil before you start it, maybe even 2-3 times... (get rid of the coolant!)
Pelican has a great writeup for this sorta thing (If you are in-fact doing this with an M50).. See their Technical Articles here:
http://www.pelicanparts.com/bmw/tech.../tech_main.htm
Post up any more questions you've got... I'll see what I can answer!
Well, i think theres still just coolant in the exhaust, because it only does it when the exhaust heats up. And the water pump leak was due to a loose bolt but im replacing the water pump now anyways. Thanks for the help and advice though, I would be lost without this site, even though I have 3 repair manuals.
well, im lost now, everything was fine, the car was running perfect. It started to idle rough and sometimes die when the rpms dropped to idle. I cleaned the iac hoping that would fix it. I took it out for a drive and it was running a good bit hotter than usual. it died almost as soon as i let off the gas and it wouldnt start back up. i checked the oil and coolant, guess what theyre both mixed. The coolant is really thick its mixed up so bad. i finally got it started and drove it home, it died when i let off the gas and wouldnt start again for a while. I started it up to move in into the garage and it's blowing white smoke again. I'm about to give up.
did you have that new head checked? Did you put the HG in wrong?
If it got hot enough from the po, your block could have a crack allowing water into the crank case...
Last edited by understr; 11-15-2008 at 05:46 PM. Reason: Automerged Doublepost
Head is fine, Head gasket was put on right. A cracked block is about the only other thing i can think of.
Damn, this sounds pretty damn close to what is happening to mine... . More investigating to come.
M52 project underway....
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