So my m50 swap ran perfectly fine for a few days when i first dropped it in a month or so ago. Then it started overheating out of the blue. Building up pressure in the system like crazy. Didn't really drive it til yesterday. Turned out the hose to the heater core was kinked so i fixed it today so where it's not kinked anymore. every line is free flowing. Put it all back together and it overheated again, what the fuck. My buddy had a spare m42 radiator to replace my m50 radiator. Put it in and it runs fine, no overheating..yet. When i got it home today i noticed the radiator hoses were somewhat stiff (yet again). His hoses with the same setup are no where near like mine, they are somewhat squishy. We don't understand how there is so much (maybe air?) in the system. I let it run for a while and everything, air bubbles just keep coming out of no where. I don't really have heat unless im driving. When i'm driving it. the heat is beastin. If it's idling for a while, it gets colder to BARELY warm. I don't understand it at all. Any input would be greatly appreciated. Any questions just ask <3
m50 swap - lot of pressure in coolant system
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Is your thermostat in corectly and with arrow up? I drilled a small 1/8 hole in mine. Makes it easy to blead. Btw your hoses will be stiff when hotNASA
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Could be air in the lines or can be a bad thermostat?sigpic
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http://www.r3vlimited.com/board/showthread.php?t=170548Comment
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All in correctly. They're supposed to be stiff when hot? shit, let me go check them now, i'll post in a few minutes. It's all cooled down now.
Brand new thermostat (doesn't mean it isn't bad), but it does open, only when it goes passed half on the gauge.
90 325is alpine2 m50b25 becoming a dorifto car.Comment
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Sorry, r3v likes to give me "Page cannot be displayed" errors 24/7. I went out and the hoses are very squishy, not stiff at all. When the car is hot the hoses are very stiff, I don't think they are supposed to be that stiff though are they?
90 325is alpine2 m50b25 becoming a dorifto car.Comment
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Excessive pressure in the cooling system after driving the car and poor performance of the heater can be from a failure to fully bleed the system, or from a leaking head gasket. In this case I suspect the head gasket since attempts to bleed the system result in continuous bubbles.The car makes it possible, but the driver makes it happen.
Jim Levie, Huntsville, ALComment
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How do you have the lines hooked up going into your heater core?
The hose off the back of the head goes to the bottom line on the core and the hose coming from the front of the motor goes to the top of the core.
Also, when you bleed your cooling system you need to have your heat on full blast to help push the air through the system. It helps to raise the front of the car up on ramps or park on a hill to be able to let the air to rise out of the rad.
If need be you will have to hold the rpms up to 2.5k for a bit and then let it drop down for a bit and do it again.
When I did a customers car it took me 1.5 hours to get the cooling system to bleed out correct. Sometimes it just happens within minutes.
Good luck.Comment
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I think the headgasket is bad too, but it's so confusing. When i take the oil cap off there is yellow creamy shit built up on it. but when i check the oil there is no creamy shit on the dipstick. just clean oil.Excessive pressure in the cooling system after driving the car and poor performance of the heater can be from a failure to fully bleed the system, or from a leaking head gasket. In this case I suspect the head gasket since attempts to bleed the system result in continuous bubbles.
EDIT: nothing comes out of the head gasket externally. internally i am unsure. Also, i am running pretty much 3/4 water and 1/4 coolant. so i dont see how that would make the yellowish shit on the oil cap. i would think it would be real watery oil.
90 325is alpine2 m50b25 becoming a dorifto car.Comment
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yeah looks like that. oil on the dipstick tube is clean.
90 325is alpine2 m50b25 becoming a dorifto car.Comment
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90 325is alpine2 m50b25 becoming a dorifto car.Comment
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Second the compression test. Also, if you have access to a pressure differential tester, do that too. Also, can't believe no body mentioned water pump. Failed water pump (plastic impeller probably broken) will cause overheat and heat out of vents to drop at idle.Comment
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Composite impeller. It over heats and cold air comes out on idle and sometimes while driving because somehow air is getting into my cooling system. which could only be my headgasket or a cracked head.
90 325is alpine2 m50b25 becoming a dorifto car.Comment



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