zoom-motorsports 0 Report post Posted September 26, 2007 hi guys just doing a motor service on my 1990 525i it has the m20 motor in it was wandering what is the correct engine oil to put in it? also my motor smells like its running way too rich what would be a course of this ?? also when the motor gets too normal running temp the idol goes up and down and will somtimes stall ??? any help would be cool thanks. Quote Share this post Link to post Share on other sites
zoom-motorsports 0 Report post Posted September 29, 2007 just found out its ment to be 10w30 fully sythetic if that helps any one out. Quote Share this post Link to post Share on other sites
Boost Junky 1 Report post Posted October 1, 2007 Hi mate, it all depends on how many km's the motor has done and other considerations like if it smokes or not? If it has done around about 135,000kms or more you want to step up a weight in your cold rating. Id probably run a 15w50 or a 15w60. The first number is your thickness of the oil when the motor is cold, the second number is the thickness of the oil when the motor has heated upto operating temperature. So in theory the higher the hot number (2nd number) the less your oil is going to thin out. As far as the funny idle goes it could be the idle control valve? Just my 2c, Luke Quote Share this post Link to post Share on other sites
zoom-motorsports 0 Report post Posted October 1, 2007 Hi mate, it all depends on how many km's the motor has done and other considerations like if it smokes or not? If it has done around about 135,000kms or more you want to step up a weight in your cold rating. Id probably run a 15w50 or a 15w60. The first number is your thickness of the oil when the motor is cold, the second number is the thickness of the oil when the motor has heated upto operating temperature. So in theory the higher the hot number (2nd number) the less your oil is going to thin out. As far as the funny idle goes it could be the idle control valve? Just my 2c, Luke mean thanks mate its high kms 300.000 so a 15w50 would be heaps better im not sure if its the same motor as it doesent burn any oil ive just rebuilt the head as the guy i bought it off snapped the cam belt haha so new valves and valve train cam belt etc etc should last me a wile so i can hunt down a 2.5 non vanos m50 motor as for my idle control valve i took it off and cleaned it out it looks like its working ok as the thing turns ??? Quote Share this post Link to post Share on other sites
Boost Junky 1 Report post Posted October 2, 2007 Yea definitely a 15w50 then. If its not smoking then that should be fine if the block hasnt been rebuilt then ur rings are doing pretty well for 300,000 haha but like you say you dont know if its the original motor. Oh dear not good im having my M50 2.5 non vanos head rebuilt as we speak, the bill has gone from $400 up to $1300 im doing the M50 conversion so worth it man. Yea i dont know alot about idle control valves but i do know they can cause that fluctuating idle... also correct me if im wrong but if u are low on water or have air pockets in ur cooling system that can cause it also? Luke Quote Share this post Link to post Share on other sites
zoom-motorsports 0 Report post Posted October 2, 2007 Yea definitely a 15w50 then. If its not smoking then that should be fine if the block hasnt been rebuilt then ur rings are doing pretty well for 300,000 haha but like you say you dont know if its the original motor. Oh dear not good im having my M50 2.5 non vanos head rebuilt as we speak, the bill has gone from $400 up to $1300 im doing the M50 conversion so worth it man. Yea i dont know alot about idle control valves but i do know they can cause that fluctuating idle... also correct me if im wrong but if u are low on water or have air pockets in ur cooling system that can cause it also? Luke no way i didnt know that about the water. what are u putting the m50 into? and what power are they standard with vanos and without??? Quote Share this post Link to post Share on other sites
Boost Junky 1 Report post Posted October 2, 2007 Putting it into my E30. I think the non vanos put out about 148kw at the motor not sure about the vanos Quote Share this post Link to post Share on other sites
euroitalian 60 Report post Posted October 4, 2007 hi guys just doing a motor service on my 1990 525i it has the m20 motor in it was wandering what is the correct engine oil to put in it? also my motor smells like its running way too rich what would be a course of this ?? also when the motor gets too normal running temp the idol goes up and down and will somtimes stall ??? any help would be cool thanks. Engine management sensor can cause erratic idle/rich mixture/engine cut out. This is the blue 2 pin one in the thermostat housing. With the engine stone cold, should have around 2.9K resistance, and this will drop as engine heats up Quote Share this post Link to post Share on other sites
