Alternator alignment issue

[NewToTheRoad]

So it looks like the PO at some point replaced the alternator, but it has no markings so I don't know what it actually is or what it's rated for.  What I do know is that there is a lot of belt dust which tells me it's out of alignment.  It's a bit difficult to tell from these pics but I'm pretty sure the alternator needs to go slightly further aft.  From what I can tell though the alternator bracket itself (bolted to front of engine) is flush with the engine with no shims.  Therefore I can't see how it can slide any further aft.  I think my 3 options are:

   1)  Change belts yearly and live with the dust (replacing one in pic with a Gates belt this week)
   2)  Replace the alternator with one that fits better ($$)
   3)  Have someone machine a custom bracket that allows the alternator to be positioned aft ($$) - There is a hose just under the tension bracket that could make this tricky.

Are these my only options or am I missing something?

note:  will use straight edge against the pulleys to determine actually how far out of alignment

Thanks!
Bryan

[NewToTheRoad]

Better image

[KWKloeber]

With my usual caveat about "eyes and hands on" it looks like the alt may need to be cocked a bit instead of wholesale moved aft?

Make sure the mount bolts are the correct ones - see the 101 on the Westerbeke bracket/incorrect bolts.

Worse come worse, you could shave a bit off the rear of the foot and shim the front. 

Send pix w/ straight edge.   

The model no. should be stamped into the frame, and/or a tag with the reg no. on the back. Have you had it off?

Change to a Dayco TOP COG belt.
AGAIN!!

-k

[NewToTheRoad]

K,
  I have not had it off yet.  I have read the post about the incorrect bolts, but didn't factor that in.  You might be on to something but yes, I need to put a straight edge on to be sure.  As soon as I do I will post back.

B

[Stu Jackson]

Bryan,

Are we referencing the same issue and Tips?

Universal M-25 & M25XP Alternator Bracket Upgrade & Alignment 101 IMPORTANT

http://c34.org/bbs/index.php/topic,7917.0.html

If so, perhaps your three options have a fourth solution:  move the bracket on the side of the manifold.

A front view picture would help, too.

Let us know.

[KWKloeber]

move the bracket on the side of the manifold.

Stu,

If the bracket is bolted tight to the water flange as Bryan's is, then he can't slide the bracket/Alt aft (as he wants to) only forward (with shims then installed.)


pic courtesy mainesail

-k

[Stu Jackson]

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>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
It's a bit difficult to tell from these pics but I'm pretty sure the alternator needs to go slightly further aft. 

>>>>>>>>>>>>>>>>>>>>>>>
Therefore I can't see how it can slide any further aft.  >>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Can we tell how I failed Reading Comprehension 101?!?   

Sorry about that.  I'd still like to see a photo from the front. 

Seems we agree on the source.

[KWKloeber]

Stu

I messed a little with Bryan's photo. 

If (big if) there's minimal distortion in it, it appears that the Alt needs to move aft about 1/3 the width of the belt.  There's only 0.15 degrees difference (statistically insignificant; basically they are parallel) between the water pump pulley (dashed line) and Alt pulley (dot-dot-dash line), so (contrary to my post below) it appears the Alt is not simply cocked CCW a bit.  Still, I'd verify that the correct bolts were used and is shimmed correctly, before attempting to move it backward.

All this is very rough because there is no doubt distortion in the photo view.

-k

[Ron Hill]

Guys : The only way to really tell alignment is to put a straight edge on the lower engine drive pully to the alternator pully.  Then play with thick/thin washers on the alternator/bracket until the straight edges match!

Easier to try that first than modifying the alternator case or the bracket itself!!


A thought

[KWKloeber]

Then play with thick/thin washers on the alternator/bracket until the straight edges match!

Ron,

I know of no way to move the alt backward by shimming.  If shims are placed to "cock" the alt so the pulley sits farther aft, then the bracket won't sit flat against the exhaust manifold.

Is there another way besides shaving some off the back of the foot of the alt, and shimming behind the front lug on the bracket?

-ken

[britinusa]

Better image

from this pic (and it's risky to put everything on a single pic) it appears that eh alternator is out of alignment with the port side being further forward than the stbd side of the alternator, hence the gap shown on the alt pulley.

Accepting that when the belt is tightened, it would have a tendency to cause that gap, the other cause of the alternator being out of alignment like that could be the bolt being too thin.

Paul

[KWKloeber]

Paul

That's what I initially concluded also.  But, when I split the pulley grooves in half, and extended a line across the pulley half, to the other pulley, the two pulleys appear to be in parallel (well, within 0.15 degree anyway.)  I also did the same, projecting lines across the face of each pulley and got similar results.  Naturally, there's the inherent limitation of distortion due to the focal point being, well, a "point" as it were, rather than a parallel panorama.  So, I'm not hanging any hats on that.   The metal straightedge will tell the tale!

-k

[britinusa]

When I thought my alternator was out of alignment and needed to be moved aft, here's what I considered.

On Eximius, the bolt supporting the alternator passes through the tongue of the mounting bracket and then through the alternator then through a spacer and then the rear tongue of the bracket.

I considered having a new spacer manufactured about 1/16" shorter and then using one or more thin washers in front of the alternator tongue effectively moving the alternator aft by the thickness of the thin washers. Additional washers would be needed aft of the new spacer in order to ensure no compression stress is applied between the alternator mounting bracket tongues.

ie. Original setup: Bolt | Mounting Bracket | Alternator Tongue | Spacer | Mounting Bracket | Nut & Lock Washer

ie. Alternative Setup: Bolt | Mounting Bracket | thin washers | Alternator Tongue | New Spacer | thin washers | Mounting Bracket | Nut & Lock Washer

As it happens, the alternator was in alignment.

Paul

[NewToTheRoad]

I apologize but apparently I wasn't receiving updates that there have been replies.  Thanks everyone for the input.

Here's an update -

I went to change the belt and for the life of me couldn't get the alternator to pivot.  As a result I was forced to remove the pivot bolt and drop the alternator to get the old belt off.  What I found was that the boatyard, just prior to me purchasing, installed a too small belt of 40".  This turned out to be a good thing though as it forced me to stop being a wimp (no exp working on engines) and just take the darn thing off.  What I found was what you all have been hypothesizing - it looks like I have the SAE bolt.  For the time being I reinstalled it with a Gates 7410 belt.  The alternator now easily pivots out and just shy of the door.  There is a lot of side to side play though, so I picked up an M10 100mm bolt and will install this weekend.  With the undersized belt the alternator was jammed against the engine and probably cocked a bit due to the bolt size so that could explain a lot of the misalignment.  It looks better with the new belt but I want to get the new bolt in before I report back.

Note:  I want to do the straight edge test but it looks to me that the pulley on the alternator is thicker than the pulley on on the engine.  So, I imagine I will need to account for that offset, meaning that the straight edge perfectly flat against both pulleys would mean out of alignment by the difference in thickness.  Right?

I have been also experiencing an issue this season where I have been hitting the start button, after 20-25 sec glow plug warming, and just get a click down below.  No chug chug of the engine turning over like usual.  If I go through the sequence 2 or 3 times more she then turns over.  Didn't do this last season.  Based on my research here I will start by assessing\cleaning the ground wire on the engine after I drop the alternator to change the bolt.  It should be more easily accessible without the alternator in the way.  I also read where the starter might need cleaning but I will start with the wiring assessment and move from there.

Thanks again everyone!  You all, and this site, as usual are invaluable.

Bryan

[mainesail]

Just clamp a spacer to the crank, such as a short piece of 1/4" thick aluminum to account for the alt pulley thickness. The distance from the straight edge to the edge of the belt should be identical at both ends.