engine and drivetrain Radiator/fan Clearance Problem

[paulram]

I picked up my car last night as I had it in the shop for a 5 speed conversion and did the radiator swap when my friend told me my old one was leaking. On the way home it seems one of my fan blades hit the radiator and put a hole in it.  I was certain we had more than enough clearance.  If someone can tell me what the problem could be that would be great.  I would not think a fan blade could flex that much but maybe it is just that simple.  The motor mounts appear to be fine.

 

After the install of the Ireland Radiator, the blade that was in the car was actually rubbing against the welds.  It was swapped out for what I think is called a tropic blade.  The profile of the blade was a lot less and gave us about 1/2" or more clearance. 

 

I drove the car locally to test out the new trans and other suspension items installed and no issues with the fan.  I got on the car quite a bit in my test drive.  No issues.

 

On my way home I went to fill up with gas. I turned right out of the station and heard a noise (which I know now was the fan blade breaking).  6 miles later I'm on the side of the road waiting for a tow.

 

I guess I should have either gone with the electric fan or the 320 Radiator. Anyway after a long night of misery, I still don't have my car...

 

The trans and suspension felt great for the 15 miles I drove it.

 

 

 

 

[M3M3]

Are you SURE the engine and tranny mounts are good? How about the left engine mount bracket? How about the movement limiter on the right mount?

The only way it will hit is if something is moving...

This is common issue btw. Many threads on it.

[thinksound_mike]

How are you engine mounts?  Were they replaced recently? This may cause the engine move forward which might cause the fan to hit the radiator, especially with less clearance with the larger radiator.

[paulram]

I have him checking everything now... In the meantime he's dropping a spare radiator into it temporarily until I figure out what I want to do.

 

It was a long night with tow and the sad drive home from Poukeepsie to NJ without the car... especially sitting in 1 1/2 hours of traffic at 11 at night cause they decided to repave Route 87...

 

Radiator... not good

[jimk]

The blades on the fan are quite long for plastic fan and bend forward when pulling lots of air.  What looks like good clearance at shut off condition, does not exist at high rpm.

[paulram]

So it would seem... The event happened when pulling out and making a hard right.  Again I didn't jump on the throttle.  Just wondering if the hard right and acceleration twisted everything just enough to make contact (especially if there is a mount issue).

 

I know the trans mounts are brand new.  Motor mounts appear to be good.  Will report on findings...

[peterschop]

There is one trans mount and two motor mounts. Motor mounts may look good but still be soft and flex. If you don;t know when they were changed last, your better off replacing them. My fan is not perfectly flat. Some blades are closer to radiator than others. With the belt off, turn your fan by hand to check clearance. As Marshall said, check the gap on the movement limiter on the right mount.

[MikeWooldridge]

I ruined a radiator and blade on my red car when road debris was picked up. If everything else checks out I would say that was your problem.

[Buckeye]

Has happened to several of us before. Easy fix. Here are a couple links to read on.......

http://www.bmw2002faq.com/topic/138820-passenger-side-motor-mount-bracket/

http://www.bmw2002faq.com/topic/84638-trans-cross-member-and-rubber-mount-question/

[bento]

Has happened to several of us before. Easy fix. Here are a couple links to read on.......

http://www.bmw2002faq.com/topic/138820-passenger-side-motor-mount-bracket/

http://www.bmw2002faq.com/topic/84638-trans-cross-member-and-rubber-mount-question/

Thanks for posting those links. I just replaced my motor mounts and that travel limiting bracket wasnt there. I had no idea anything was missing. Something else for the list... I'd prefer to keep my fan out of the radiator.

[Mike Self]

Paul--FYI those bent fins on your radiator can easily be straightened (out of the car of course) with a small pair of needlenose pliers and a little patience.  I've straightened much worse and had 'em looking like new.  

 

+ 1 on checking motor mounts, the left side motor mount bracket (notorious for cracking) and the tranny mount--replace this one with one from a Bavaria or E21 rather than the factory item.  

 

mike

[paulram]

Mike,  If you look at the bottom of the rows where the fan hit, they are leaking fluid.  I need to see if they can be welded.  It would seem a difficult if not impossible task but I'm sure anything is possible.

 

Anyway the right front mount is a bit soft, but not broken.  The engine sits pretty securely.  Mounts / flex are the only answer it can be.  I replaced the IE radiator with a 320 radiator and drove the car home up to 80MPH with no issues.

 

Feels like a new car.  Was just doing the 5 speed conversion but ended up with new bilsteins, IE Springs, ST Bars (from PO), new ball joints, control arms and all bushings replaced. Tons of other stuff done too that seem insignificant but bug you every day...

[Mike Self]

I see the holes in those lower tubes; you should be able to find a shop that can weld up the aluminum, but they will mess up the fins in the immediate vicinty of the holes.  

 

The bent fins above the holes are what I was referring to.  I've used jewelers needlenosed pliers (miniature versions of a regular sized one--get 'em at Sears) to straighten bent fins, one at a time.  Time consuming but makes the radiator look good as new.

 

A number of folks who've used the Ireland radiators have reported clearance problems, and more than a few were traced to cars that had previous front end sheet metal damage.  Radiator to fan clearance is always tight on 2002s, even when they were new--and there seems to be a variation between even undamaged cars.  

 

Just keep an eye on your plastic fan.  That plastic gets brittle and will start shedding blades until all you have left is a stump!  (Ask me how I know this!)  And a spinning blade can do a number on your radiator as it parts company from its hub (I was lucky there.)

 

mike

[nbcbird]

They also make a "comb" designed to straighten radiator fins.