Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts

Stu Jackson · August 12, 2012, 04:54:27 PM

The front of the 1 1/2" screw. 5/16" SAE, the M8 is on the foot of the alternator.

Stu Jackson · August 12, 2012, 04:56:57 PM

The screw w/ washer in front, nut and lock washer aft.

mainesail · August 12, 2012, 05:06:23 PM

Quote from: Stu Jackson on August 12, 2012, 04:54:27 PM
The front of the 1 1/2" screw. 5/16" SAE, the M8 is on the foot of the alternator.

Stu,

Please tell me this is a joke?

There is no way you will ever get a Phillips head tight enough to keep that adjuster arm from moving. You also want a thick washer to better distribute the load to the arm on both sides of it. You can buy grade 8 washers that are double the thickness. Get yourself a grade 8 or 10 bolt with hex head and your issues will be gone.....

Ron Hill · August 12, 2012, 05:31:49 PM

Stu : I fully agree with Mainsail. Even though this end of the adjusting arm is almost stationary and only rotates, you need a hex head bolt/washer/lock washer !!

In NO way do you ever want bolts that are too long (just about flush in the rear) or stainless or not a hex head. The bolts need to be steel. You can use stainless washers flat or lock, but the bolts need to be steel.

My thoughts also

Stu Jackson · August 12, 2012, 05:39:50 PM

It's so much fun to get to do things all over again. By the time I'm done, I may actually have a clue. Makes sense, the front of the screw is making the pressure on the arm. Lag bolt woulda been much better, 'cept that didn't work last time, using Ron's "long bolt" theory. But for sure, it's 5/16" by 1 1/2". Learn somethin' new everyday. Thanks, guys.

The REASON I bought the screw was that they didn't have any lag bolts without shanks in that length. Would simply doubling up on the washer work or is that "just not done?"

Heck, the "KIT" didn't come with much of anything, re" washers...oh, yeah, lock nut & washer (standard!).

mainesail · August 12, 2012, 06:27:38 PM

Just go to a Fastenal or your local nut & bolt wholesaler and get that bolt threaded the entire length...

Stu Jackson · August 12, 2012, 06:29:51 PM

Will do, I love my ratchet set!

Stu Jackson · August 29, 2012, 04:59:05 PM

You're right, the screw didn't work.

How's this?

Ron Hill · August 29, 2012, 05:33:06 PM

Stu : The hex head bolt and a lock washer is the way to go!!

HOWEVER, if you look back at your photo in reply #10 you need to get the belt aligned by moving the alternator forward!! Get rid of the washer between the bracket and the adjusting arm and you might even have to have the bracket bent fwd !?!

The belt should have a straight shot from the water pump pulley and NOT be bending aft!!

A thought

Stu Jackson · August 29, 2012, 05:57:27 PM

OK, I agree. Today I tried to get the two washers in BEHIND the alternator into the bracket to get it lined up. Couldn't do it. Any Ideas?

mainesail · August 29, 2012, 06:45:06 PM

Quote from: Stu Jackson on August 29, 2012, 05:57:27 PM
OK, I agree. Today I tried to get the two washers in BEHIND the alternator into the bracket to get it lined up. Couldn't do it. Any Ideas?

See my earlier post in this thread with all the photos. The brackets are adjustable. You probably need to go forward with it.

Stu Jackson · August 29, 2012, 07:18:13 PM

Understood.

Here's the "BUT": The distance between the "ears" of the bracket and the alternator are different. I would think that the alternator should be tight in the "ears" but the space has me concerned, based on previous issues with the top of the alternator over the pivot bolt getting worn out from wobbling.

I simply couldn't get the new pivot bolt into the two bracket holes with the two shim washers.

mainesail · August 30, 2012, 04:33:53 AM

Shim washers often have to be made thinner. The fit of the alt foot in the mount should be snug. If it is too loose you will either have alignment issues or snap the bracket when tightening it..

For custom shims I use a belt sander to shave them to the exact thickness I need. Some patience, a piece of glass or other flat surface, and some wet sand paper can achieve the same outcome... I used to have a source for copper shim washers but it dried up.

Ed Shankle · August 30, 2012, 09:58:46 AM

Had the same problem Stu. So what I found that works is, inserting the round shank of a screwdriver from the back "ear" forward, add the shims, spacer and alternator. Wobble the screwdriver around to line up the hole, then push the pivot bolt thru from front to back. I used a phillips head because my larger slot screwdrivers have a wider than shank head.

Ed

Stu Jackson · August 30, 2012, 05:57:07 PM

FILLING THE SPACE

The Challenge: Fill the space between the end of the ear and the alternator.

Choices:

1. Remove alternator yet again and try Ed's idea (thanks, Ed, a good one).
2. Cut metal washers and slip them over the bolt - wouldn't work, too stiff
3. Try nylon washers, cut them and slip them over the bolt to fill the hole

Here's what I did. Ran the engine, good belt tension with the new bolt, and alignment was much better.

Hotter alternator? We'll see...