I am now ready to install my generator. Thank you for pointing me in the right direction to get the right field coils for my generator. I am now going to tighten the belts. I want to do it before I install my radiator to get some more space. I thought this was going to be an easy job? Generator is mounted to the bracket with the "strap". The bolt for the generator bracket (7/8 head) and the 2 for the fan hub (5/8 head) are all loose. Here comes finally the question!
I was reading somewhere you could brake something like the guide/slot in the intake when pushing the bracket to tighten the belt for generator/wp. Can you please explain how to avoid this. Thanks!
Mats Nilsson, Sweden

 

You are wise to do this with the radiator out given the opportunity. I find that this is one of those things that is easier once one has a feel for it. I use a narrow long pry bar to position the fan assembly (not much pressure). I don't immediately recall my fulcrum point, but it was pretty obvious at the time. Be sure to adjust the generator first. Part 12 of Chapter VI in the service manual covers the process, and there is this video that may help too:

 

The parts that can get broken off are the guide rails that the gen mount rides between (below). They usually get broken when the gen mount is cocked and the big nut is tightened.

If you have an engine hoist handy, a strap around the generator (towards the front) will let you raise the gen up in a controlled, pain-free manner. Remember that the belt doesn't need to be real tight, too tight will be hard on the WP and gen bearings.

 

As Ross said, an engine hoist works well. If you don't have one, I have laid a 2x4 across the fenders with a chain or strap under the generator. Use a pry bar under the chain/strap with one hand and tighten the 7/8" nut with the other hand.
Also, leave 1" of deflection on the belt. Too tight is a disaster if you drive your truck much at all. I lost a water pump bearing on a cross-country trip US and lost a generator bearing on a trip back from Lethbridge Canada. All because the belt was too tight. I finally learned my lesson.

edit: yes the manual says 1/2" but that's too tight in the real world IF you actually drive these as a daily driver. Your mileage may vary.....

 

Doesn't your shop manual tell you how much deflection the belt should have on a flathead?? The 53/55 manual says there should be like a ½" deflection in the belt between the Genny and the fan for a yblock.

 

Yes, 48-52 is also 1/2" deflection.

 

I dont want to overcomplicate it again!!! And the shop manual is good. Just wanted to ask you because I remember I read somewhere about the guide rails on the intake. Now I understand how the mount/bracket moves. Thanks a lot and have a great Christmas everyone!!!!!!

 

I had trouble adjusting my belts as well. I tried to find a spot to use as a fulcrum with not much success. In the end, I used an hydraulic jack and a 1x2. I put the jack under the truck, wedged a piece of 1x2 under the pulley, and used the jack to tighten the belts to spec.

 

What is the shop manual recommended way?

Tightening yblock belts is easier.

 

The manual is a BIG help.

 

You're right. That is a "big" help. One question though: where do I get my thumb calibrated to find "normal" thumb pressure?

 

Ya Abe you right as rain about the Y Block being a lot easier. Still run my Generator. But had to reweld my bracket, The shop manual does say 1/2 inch I have a little over a fourth. On my tension. I really like the Daco belts I bought at NAPA. Merry Christmas!AJ