Radiator problems caused by suspension mods? - PeachParts Mercedes-Benz Forum

greasybenz · #1 12-10-2008, 01:11 AM

Hey guys havent been on the forum for awhile. And the poor 87 300D hasnt been driven for awhile either. Well here is the scoop. This is probably the 5th radiator ive gone through with this car (thank god for autozones lifetime warranty) the problem is that the fan shoves itself into the radiator under hard braking. Then pokes a hole and out comes the coolent.

Now i tried narrowing down the problem with the fan, the engine had too much give so i replaced the motor mounts and gave it some hard braking. 3rd radiator blew so i thought maybe the transmission mount, changed it and realized that the old tranny mount has as much play as the new one! so there went the 4th radiator.

Now my only guess is that the lower radiator mounts are bent making the radiator sit too close to the fan. I have the AMG suspension on the car which really lowers the car. Since i havent driven the car in a very long time that last i could remember was my dad borrowing the car and complaining about the nose scraping over everything. And im sure the front has hit the curb coming out of his driveway.

Am i missing some mounts that i need to look over that might causing the engine to move around to much? Or could it possibly be the lowered suspension causing the problems?

babymog · #2 12-10-2008, 09:51 AM

I'd bet the lower radiator support is bent rearward, putting the radiator too close to the fan. There should be inches of clearance.

Simpler=Better · #3 12-10-2008, 10:04 AM

I'm a 617 guy, but I have 2"-3" of space between the fan and radiator.

If messing with the radiator mounts doesn't work you can always remove the fan and put in a thermally regulated electric fan

greasybenz · #4 12-10-2008, 05:21 PM

Yeah i think the lower support bent from curb jumping. I guess my solution would be to go with an electric fan but im worried about clearance, from the looks of it i have about 1inch of clearance between the fan and radiator now. It might actually be a bit less then an inch

Any suggestions on good electric fans?

sixto · #5 12-10-2008, 07:31 PM

Hi Ruben,

I measure about 20mm between the forward tips of the plastic fan and the radiator core. I can't fit the width of the red dot key head between the fan blade tips and radiator core. 148mm from the flat front face of the head to the aluminum top of the Behr radiator (not the bump around the slot for the shroud), and 192mm from the head to the body color radiator frame. The fan gap is even throughout meaning the planes of the fan and radiator are parallel. Is your fan original? I don't know if these cars came with metal or plastic fans. Mine's plastic but I didn't own it for the first 200K miles.

I don't know what can cause an engine to shift an inch forward but I'd look into it

Make sure the mounts are on tight and the mount arms are tight against the block. Look for cracks in the crossmember and mount arms.

Go with a SPAL puller.

Sixto
87 300D

babymog · #6 12-10-2008, 07:44 PM

Metal fan is original.

greasybenz · #7 12-10-2008, 09:23 PM

Its a plastic fan, ill check the arms on the block.

Thanks guys.

winmutt · #8 12-10-2008, 09:34 PM

How much clearance is there? You didnt say which side of the fan is hitting first. Top middle or bottom?

MBeige · #9 12-10-2008, 09:34 PM

Why not just have it properly done and fix the lower radiator support crossmember instead?

greasybenz · #10 12-10-2008, 09:55 PM

Quote:

Originally Posted by winmutt

How much clearance is there? You didnt say which side of the fan is hitting first. Top middle or bottom?

The fan hits the red mark on this radiator. You can hear the fan brush up against the radiator under hard braking.

greasybenz · #11 12-10-2008, 09:57 PM

Quote:

Originally Posted by MBeige

Why not just have it properly done and fix the lower radiator support crossmember instead?

2 Problems.

1: The lower radiator support is part of the chassis. I can probably try bending back into shape but there isnt a replacement part.

2: Due to the fact i have lowered the car with the AMG suspension i have a feeling it will happen again if i have it fixed. So a better solution would be to find a alternative like an electric fan.

Johnhef · #12 12-10-2008, 10:39 PM

Look familiar? I'll bet the radiator support is bent backward. This is what happend to mine after hitting a dip in the road. No visible damage to the bumper, just a quick jolt to the rad support and pop goes the fan and radiator. I used a 1/2" extension and a 2lb hammer to knock it back into place.

greasybenz · #13 12-11-2008, 12:39 AM

Quote:

Originally Posted by Johnhef

Look familiar? I'll bet the radiator support is bent backward. This is what happend to mine after hitting a dip in the road. No visible damage to the bumper, just a quick jolt to the rad support and pop goes the fan and radiator. I used a 1/2" extension and a 2lb hammer to knock it back into place.

Oh damn! Yes! exactly like that only my fan isnt as bad, few chips is all.

Ill try doing the same to see if i can get the mount in the correct place. After you got it back into its correct position have you had the problem anytime after? Because i honestly dont want it to be a constant burden or i may have to retire the suspension and go back to stock.