smiddy 76 Report post Posted May 27, 2008 Hi guys, noticing rummbling noise from front of car mainly when cold, suspected water pump. When engine is shut down noise continues till drive fan stops, on inspection bearing has some play and is rough. As an ex motor mechanic- be it 25 years ago was keen to fix myself. Any precautions or advise? Thanks. Quote Share this post Link to post Share on other sites
SIR E30 68 Report post Posted May 27, 2008 Hi guys, noticing rummbling noise from front of car mainly when cold, suspected water pump. When engine is shut down noise continues till drive fan stops, on inspection bearing has some play and is rough. As an ex motor mechanic- be it 25 years ago was keen to fix myself. Any precautions or advise? Thanks. Dont buy a second hand viscous coupling, you will never know if its good until its in the car and running.Also, a handy hint: The nut that holds the fan on is huge and has a reverse thread! Good Luck! Quote Share this post Link to post Share on other sites
westy 614 Report post Posted May 27, 2008 If it is the water pump pulley, replace the waterpump quick! The fan can make a right mess in there. But since it continues after the engines shutdown its probably the viscous coupling. Quote Share this post Link to post Share on other sites
SIR E30 68 Report post Posted May 27, 2008 (edited) Hey there, Ive been thinking about this today while working away. Ive come to the conclusion that it more than likely is the viscous coupling. The fan has a sort of clutch in it which is meant to slip and not spin fast when the engine is cold and when it heats up the clutch will grab and the fan will go at full speed. That explains why you hear the noise when the engine is cold. Does the temperature get higher when you sit still at lights or in traffic and then cool down when you drive off? If so thats a definite sign that your viscous coupling is gone! My E30 did the same thing a few months ago. I have the receipt in front of me, a new viscous coupling from SD European in Hamilton set me back $175 plus gst ($196.88) Make sure you get the right one, there is a 4 bolt and a 3 bolt version. Another thing you can do to check if it is the fan is when the motor is dead cold spin the fan with your hand and see how long it takes to stop. It should only take a few seconds. Then keep spinning the fan for about 30 seconds to a minute and if it starts to get loose and take longer to stop that means the coupling is stuffed. Happy trouble shooting! Jason Edited May 27, 2008 by SIR E30 Quote Share this post Link to post Share on other sites
smiddy 76 Report post Posted May 27, 2008 Thanks Jason,the fan spindle appears to have a lot of rock to and fro and can be heard and felt when spinning fan by hand. My main concern is the fix process: can a bearing be fitted, or is complete fan unit required? Thanks for your help. Quote Share this post Link to post Share on other sites
SIR E30 68 Report post Posted May 27, 2008 (edited) Thanks Jason,the fan spindle appears to have a lot of rock to and fro and can be heard and felt when spinning fan by hand. My main concern is the fix process: can a bearing be fitted, or is complete fan unit required? Thanks for your help. Yep you're in luck, you can take the fan blades off the coupling and replace just the coupling itself. Thats where the 3 or 4 bolt thing comes into play.Undo the bolts on the motor side of the fan 8mm or 10mm... cant remember, and its too dark to see at the moment. This will make the fan blades come off the coupling and give you better access to the big nut that holds the coupling on. Remember, the big nut is a reverse thread. Also.. Just be careful not to slip or push the fan into the radiator, this can cause damage or even death to a radiator!! My mechanic found this out the hard way... Edited May 27, 2008 by SIR E30 Quote Share this post Link to post Share on other sites
kerrynzl 3 Report post Posted May 28, 2008 Hey Wayne , try and do it the easy way. On a M50 - M52 engine there is a large nut on the waterpump pulley 32mm and L/H thread. You will need : A dozen cans of your "favorite drop" A 32mm open end spanner or a 1-1/4 imperial will do A hammer A trusting mate [ or a pissed mate will do ] Get your mate to hold the pulley around the belt as tightly as he can, with the spanner on the nut give it a twack with the hammer [ not in the Gus fashion though ], It should then come undone as a complete assembly, real easy. Now you have plenty of time to consume the leftovers from your favorite drop [ depending on how much your mate drank for bravery ] Seriously though, just crack it loose with a hammer and undo it [ they are not that tight ] Quote Share this post Link to post Share on other sites
smiddy 76 Report post Posted May 29, 2008 Hey Wayne , try and do it the easy way. On a M50 - M52 engine there is a large nut on the waterpump pulley 32mm and L/H thread. You will need : A dozen cans of your "favorite drop" A 32mm open end spanner or a 1-1/4 imperial will do A hammer A trusting mate [ or a pissed mate will do ] Get your mate to hold the pulley around the belt as tightly as he can, with the spanner on the nut give it a twack with the hammer [ not in the Gus fashion though ], It should then come undone as a complete assembly, real easy. Now you have plenty of time to consume the leftovers from your favorite drop [ depending on how much your mate drank for bravery ] Seriously though, just crack it loose with a hammer and undo it [ they are not that tight ] Thanks for that Kerry, you come round and do it! Iget brown liquid! Quote Share this post Link to post Share on other sites
