blondeau67

I just installed a 4 row aluminum radiator into my '87 Trans Am. Not a fancy one, but better than my leaky plastic-tank OEM radiator. It's partially back together, I need to make brackets to bolt it to the stock mounting points rather than the zip ties I used to get it home from where I did the work.

My issue is that my electric fan now seems to be hitting the inside of its shroud, even though I am fairly sure we tightened the bolts that mount it to the upper mounting bracket all the way. Does anyone have any idea why the fan might touch the shroud now or what could cause it in general? We didn't knock it around or anything, but could it be imbalanced? Could it be imbalanced because it is on a slight angle since the new rad is taller and thicker than the stock one?

When I get home I am going to make sure those bolts are tightened, then I can add some pictures. Until then, thank you for any help!

91banditt2

iTrader: (1)

A 4 row rad seems a bit over kill for a 305 or a mid 350.
Are you running a pusher or puller fan? Are you using a factory single/double fan setup? If you are and your using wire ties the plastic fan mounts which are fairly flexible could be tweeked a bit causing the fan to scrape. My 2 row Champion plus puller fan mounted to an aluminum fan shroud is about 2-3" from the water pump pulley, with the 4 row could there be interference with the water pump pulley/bolts?

blondeau67

It was like $10 more than the 3 row. I am guessing puller, if it means what I think it means. Also factory electric single fan. Hm I suppose our idiotic selves could’ve tweaked the plastic. The clearance to the water pump is still 2” or so.

the rad is on an angle so I am wondering if that puts the fan off-balance? Could I bend up the bit of core support that doesn’t allow it to sit totally vertical to slide the radiator back straight if the fan is off-balance?

91banditt2

iTrader: (1)

A puller fan would be mounted between the rad and the motor pulling air from the outside through the rad
A pusher fan would be mounted on the outside of the rad pushing air through the rad
Typically electric fans don't really care about how they're mounted.
The radiators in these cars don't sit in the core support vertically, they do have a slight angle.

Scott's 83' Z

Something to check. I have ordered AC Delco (single fan) blade assemblies from Rock Auto but have gotten two that were warped. It was enough to cause the fan blade to not rotate inside the shroud without rubbing.

blondeau67

Ah so that shouldn't be the issue then. This rad is definitely on more of an angle than stock though.

As per the fan being warped, this fan is the one that has been on it since before I bought the car. It never made a noise until we got the new radiator in. I suppose we could've warped it when taking it out/putting it in though, which would suck.

8t2 z-chev

the fan bracket is distorted out of shape from non-original mounting-just rework the mounting points so the four bolts are straight and bracket will spring back into shape.