Fan blade hitting radiator

[pdx2002]

I put my car up on jack stands to swap out an old drive line. When I brought it down I noticed the fan blade is now hitting the bottom of the radiator when the motor runs. I checked the transmission mount and noticed it was way past its prime, so I replaced that. Now the sound is even worse! I figured by raising the back end of the transmission, it may move the bottom of the fan blade away from the radiator, clearly it hasnt. I can see the spot where the blade hits, so I know it's at the bottom. Does anyone have any experience with this problem? Thank you, Andrew.

[colorobo2002]

Bad motor mounts.

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[Hans]

 Do you have the limiter bracket attached to rt side motor mount to prevent that? Is so, is it adjusted properly?

[pdx2002]

motor mounts are brand new.  I swapped them out 500 miles ago when I did a suspension refresh.  Come to think of it, we had this problem when we did the suspension, and it didn't exist before that.  So, I see what you mean about the motor mounts.  How could putting new motor mounts in create this problem?  I assume there are adjustments at the mounts.  Sorry for confusing feedback, the fella who helped me with the suspension has been working on these cars for years, and I didn't see how he adjusted the motor at that time.  I'll do some research on the limiter bracket, as that is new to  me.  Thanks very much for your kind suggestions, I'm trying to learn this stuff, and will pass the knowledge onto my kids. 

[Mike Self]

If you have an early roundie (68-sometime in 1970 or early 71) the OEM pax side motor mount is simply a bent over piece of heavy steel.  It will stress crack and fracture over the years, and allow the motor to shift.  That design was replaced with a welded up mount that has adjustable limiting brackets.  If you have a car with that early style mount, you should replace it.  The one on my '69 fractured and bent at about 140k miles, allowing the engine to start hitting the hood when I revved it.  Had it broken completely, it would have dropped the engine onto the center track rod, affecting the car's steering.

 

mike

[Hans]

There is a drawing in the Haynes manual.

[Buckeye]

You did not mention what year car that is, but from your avatar appears 74 -76. Anyway, below is showing R.H. mount and limiter bracket and setting on that bracket. Let us know what you find out.

[echappe]

Is it possible to move the whole drivetrain back?

[colorobo2002]

Yes, especially if you removed the subframe. There is play from the subframe all the way back to the rear diff.

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[Hans]

Thanks Buckeye for the photo. That is an important item

[pdx2002]

76' Siennabraun, 5/76 manufacture date. 

Yes, thank you very much for the photo. I'll source that from my Haynes manual. All suspension components were removed from the car when we did refresh, so the entire assembly could be slightly forward, however I would think that would have shown up as an issue when we reattached the driveshaft. I will attempt to adjust limiter bracket in the passenger side mount this evening and report results. I really appreciate the help guys! Andrew 

 

[jimk]

1 hour ago, pdx2002 said:

the entire assembly could be slightly forward,

Nope, the front subframe is dowel located.  The subframe to frame rail bolts couldn't be put back in if the dowels were not seated.  To shift the engine/trans rearward, the diff to rear subframe bolts need to be loosened or the guibo will be messed up.  Of course, there has to be available space in the diff mounting bolt slots for it to moved back.

Edited January 30, 2017 by jimk

[TobyB]

Quote

the diff mounting bolt slots

Phew- thanks, Jim, I thought we would never get here.

 

Anyway, what Jim's saying is that YES, you can move everything back IF you have adjustment left at the diff.  It has about 3/8" of movement built into it.

The 4 m12 bolts that hold the diff to the subframe have slots, and if you take one out, you can see where the diff is, relative to the slots.

I get under the car, loosen the diff bolts, hang off a subframe, and shove the diff with my feet.  That seems to be the best way to get it all the way back.

That moves engine, trans, everything back.  If you have adjustment left...

 

And is why when you buy an older BMW that's been hit hard enough to touch the water pump, you check the output shaft bearings on the trans, 

the diff input bearings and crush sleeve, u- joints in the driveshaft, etc.  A hit in front can bust the diff free of the subframe, if it happens just right.

 

t

 

[pdx2002]

Okay, that makes sense. The bonnet has paint peeling away on the underside. It reveals a red paint, so I know it's not original. Maybe there was front end damage at some point. I'll check the diff and see if there is any adjustment. Are you suggesting I put the car on jack stands to move everything? I would assume you need the wheels off the ground to do this.

[TobyB]

yeah, unless you're really skinny...

...or are rollin' on 26's.

 

Unless you see panel damage of the front support, it's not possible to shorten a 2002 very much at all by hitting it-

and not having it be pretty obvious that it's been hit.  Stuff will be seriously messed up if the car's been shortened 1/2" in the sheet metal...

 

I tried it once.

 

It hurt.

 

t