how close should the fan be to the radiator?

[FiveSpeedSquirrel]

I am tracking down the radiator problem on my 1988 325is. The fan has punctured the radiator and after a mass exodus of coolant, I am replacing the radiator. I just bought the car recently from an auction, so i don't know much about its maintenance history.

I have looked closer and I see several areas where radiator fins have been flattened by the fan. I also see that the ends of all of the fan blades are chewed up, to varying degrees. The fan looks closer to the radiator on the bottom (about 1/4 to 1/2 inch) than the top (about 1/2 to 3/4 inch). There is also a lot of wiggle/play in the radiator itself, so I can imagine that when the car accelerates hard (as it did during "the incident"), the radiator would flop back to its farthest back position. The upper bracket with the two rubber grommets doesn't seem to be doing much in the way of keeping the radiator in place.

Is this clearance an issue for anyone else? Is my fan too close to the radiator? It seems to me that you would want at least 1-2 inches of clearance in this area just to be safe, since the fan is mounted on the engine and not some sort of fan shroud (like it would be on a FWD car).

I know that the issue could be my motor mounts, but with such obvious issues with the radiator, I figured it's a good place to start. My biggest concern is that I will replace the radiator and this will happen all over again.

[vr2jetta]

My radiator sits nice and tight in there. I cant check the spacing now because the wife has it at work (its close but there is at least an inch) but you may want to check all the rubber mounts (top and bottom) to be sure its in there tight. Also check to see if there has been any front end damage that could have pushed the mounting tabs closer to the radiator.

[FiveSpeedSquirrel]

I just looked up the fan on Pelican Parts... my fan looks like the one they have pictured for the early 325 (09/1987 or before), but it should resemble the fan from one of the later cars. Maybe that could be part of the problem.

[jlevie]

Damage to the radiator core support, wrong radiator, improperly mounted radiator, bad water pump, bad fan clutch, or bad motor mounts are all possibilities.

[FiveSpeedSquirrel]

how would a bad fan clutch or a bad water pump result in a clearance issue like this?

[jlevie]

Those parts when worn can allow the fan to wobble, resulting in reduced clearance during part of a revolution of the fan.

[FiveSpeedSquirrel]

Those parts when worn can allow the fan to wobble, resulting in reduced clearance during part of a revolution of the fan.

Is this kind of "fan wobble" something that I can watch while the car is running? I figure that if it's enough to make the fan strike the radiator, it should be perceptible while the engine is running.

[T Verdier]

I know people who take out the engine fan and just run the aux fan with a lower temp switch this sounds like the easiest way to deal with the problem. It doesn't take much to see if the motor mounts are bad I went through a couple of lower radiator hoses befor I changed mine. But when your motor mounts go bad usualy the motor doesn't move forward but side to side since the trany mounts keep it held back.
But I'm no mechanic this is just my geuss.

[tecks2k]

Those parts when worn can allow the fan to wobble, resulting in reduced clearance during part of a revolution of the fan.

This man speaks the truth ... just got done dealing with it. I had an E36 M3 radiator in my e30 which has less clearance then a normal e30 radiator and I recently just ran into the same problem.

As for replacement I ordered an E30 radiator, it allows for a lot more room between the fan and the radiator.