TR2/3/3A Fan to Fan Hub Extension Torque Data TR-3

[Tinkerman]

I'm bolting my fan to my fan hub extension and find no torque data in the manual. Do I just mush it down until it stops? There are some rubber washers in the fan hub, not sure just how enthusiastic I should get.

Any thoughts would be greatly appreciated.

Tinkerman

 

[martx-5]

There should be sleeves inside those rubber bushings so the rubber will only squish just so much. I don't remember the size of the screws, but if 1/4", about 10 ft/lbs., if 5/16" about 15 ft/lbs.

Edit: you are right about no torque data in the manual for those bolts, but if you look at other torque data for the same size bolts, that will give you the info you need. That is how I got the figures I gave you.

 

[DNK]

I was going to say that the size of the bolt usually determines torque. But then I saw he mentioned rubber and I would need you torque geniuses to say if that changes anything.

 

[martx-5]

I was going to say that the size of the bolt usually determines torque. But then I saw he mentioned rubber and I would need you torque geniuses to say if that changes anything.

The rubber doesn't change anything in this case, as there are steel sleeves inside the rubber. Therefore, the torque is to hold the steel sleeves onto the hub extension. It's just that there is rubber between the sleeves and the fan. I think I got that right. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

 

[Tinkerman]

Art, you are correct the steel sleeves are cushioned by the rubber grommets. I also suspect that the steel sleeves serve as an upper limit to the amount of torque I can put on the bolts. All that makes sense to me, but I thought I would throw it out there and see what you all had experienced. My concern is that since there are rubber grommets if they are not tightened to the same torque I could have a wobble problem with the fan. My wife some times , quite often I might add, tells me that I tend to over engineer everything. I might be doing that now.
I seem to remember as a young man not sweating the little details, now I do. Guess it comes with age and experience, heh.

Tinkerman

 

[martx-5]

... My wife some times , quite often I might add, tells me that I tend to over engineer everything. I might be doing that now.
I seem to remember as a young man not sweating the little details, now I do. Guess it comes with age and experience, heh.

Tinkerman

She's right. Listen to her. I find myself caught in the same trap as you. Getting older just seems to make us sweat the smaller stuff more, when it should be the other way around. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif

I'm going through this TR3 engine rebuild now, and I can't tell you how many times I went over things I just went over twenty minutes ago. Man, I spent a half a day fiddleing around with degreeing in a cam, and wound up putting it on the the original marks! /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif

Edit: If you do have wobble, which you probably will, it's because the fan is bent. (That should open up a can of worms). /bcforum/images/%%GRAEMLIN_URL%%/sick.gif /bcforum/images/%%GRAEMLIN_URL%%/jester.gif