M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: Avtovaz on November 28, 2011, 04:22:38 PM
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my m42 motor overheated on t eh weekend, not exactly sure how, but it had a hard run, then stopped, and driven slowly for 2-3 km. when i stopped i heard water and steem comming from the bonnet area but as i had not long been threw water, i thought it was just water exapotrating off the rad etc.
I was checking the temop guage, and it was fine. I noticed the car went onto 3 cylinder, and it was then i stopped , the car cut out. I tried to start it again and the starter a 325i one would not turn the motor very fast at all.
When it cooled the motor turns liek it has no compression.
I think when i went threw the water a stick has wedged teh viscus fan, and whe i stopped the motor got hot quite quickly. Then driving off its started to cool down and then the damage has happened.
some questions
at no point did the temp guage go up, it was always on normal, but it had no water in it, why was that?
what is likely to be salvagable from this motor? I mean, i just rebuilt it and i dont want to throw it away but having said that, there is a 200k m42 on ebay cheep, and also there is a m44 for £300
what should i do?
thanks!
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I would start with a compression test. Check the radiator expansion tank for pressure when engine is cold. should be none Check / drain oil and check for milky color . Remove spark plugs, Look for wet plugs that smell like antifreeze look inside each cylinder to look for water on top of the piston, rotate engine using the starter and see if water jets out of any of the spark plug holes. I would also replace this water temp sensor asap, good luck with this.
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Remove all of the spark plugs,look inside each cylinder for water on top of the pistons, rotate the engine using the starter, check for water exiting the spark plug holes, conduct a compression test on all cylinders. Check each removed plug for wetness and the smell of antifreeze. Check the radiator expansion tank for pressure when cold, should be none. Drain the engine oil level (if its high thats where the water went) and then drain oil and check for milky color. Change the engine water temp sensor asap. Good luck with this.
***I approved this post, I know it's a duplicate. Feel free to delete or change it as required***
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yes, I overheated mine and did not realize it either. If you loose water, then the sensor is not sensing anything, and the guage sometimes just sit at half way, not indicating an overheat when your head is actually toast. Maybe...thats what happened to me anyhow. The head has a crack in it too, its not just the gasket. If you have a little luck, you may get away with a replaned head and a new gasket, but in my case the head is done.
they do NOT tolerate being overheated
Geoff
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Right, sounds just about right then, is the bottom end going to be scrap too?
I have just worked out that its £100+ for a head, and £50 for a gasket set so i can get a second hand motor for about that.
I have found out today that a stick or simular has come threw teh grill on teh bumper, smashed the rad couling, knocked the rad off one mount which has stopped the visc fan from turning. So overheating was inevitable...
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The bottom end is very robust and should be fine as long as normal oil pressure was maintained while all of this was taking place.