Universal M-25 & M25XP Alternator Bracket Upgrade & Alignment

[mainesail]

Hi All,

After many pokes by my site readers I finally finished my article on replacing the alternator bracket on an M-25... There are lots of details & pictures... Hope this helps....


M-18 & M-25 Alternator Bracket Upgrade (LINK)

[Ron Hill]

Guys : As Mainsail points out you are looking for trouble if you use an undersized diameter bolt when mounting a heavy alternator.

In the case of some Balmar and other brand alternator cases, if you can't use a larger diameter bolt, get a sleeve to take up that slop between the bolt and the case hole.  A tight fit is imperative!!

A thought

[Stu Jackson]

ALTERNATOR REPAIR SHOP

I took BOTH of my Blue Circle alternators into a local alternator shop here.  I'd saved the one with the broken pivot arm shown in Maine Sail's link, and also brought the one I'd been using in, too.

I learned about this shop from Chris Stewart on the C36 Forum (http://www.c36ia.com/forums/showthread.php?t=1191).  Gen Star, 1367 Willow Street, Oakland, CA, 94607, 510-893-6161, 800-828-3131, John Stack.  He's very helpful, explained the guts & gore of the inside of alternators, and bench tested the one I'd been using to check it worked.  Turns out the bits & pieces Harvey used on the Blue Circle didn't rate for the offered amperage, and there are better bits and parts that could have been used.  Ya get what ya pay for, although I'd go Leece Neville before Balmar, same thing without the markup.

While I was, ahem, "at it," I took the opportunity to move my alternator bracket to the Forward Position as Maine Sail described in his link.  This will allow me to align the alternator pulley with the other two pulleys (finally!  ).

This level of detail was not available back in 1998 when I broke my old bracket (from the tech wiki: http://www.c34.org/wiki/index.php?title=M-25_Alternator_Mount_Conversion_Kit_%22B/M_256891%22).   Don't forget the Critical Upgrades, too.

While it always says: "Align the pulleys," the instructions for the bracket upgrade don't mention it.  This ability to align the bracket applies to BOTH M25 and M25XP engines.

Yesterday I had PB Blasted the four nuts on the manifold studs and the adjuster arm bolt and nut.  They released today quite easily, no stripping anything.     I spent some time at our local hardware store to replace all the nuts & bolts with new (metric ss) ones.

Lessons learned:

1.  Now we know how to align the alternator pulley! 

2.  It's always good to have a reputable alternator shop known locally.  Find one in your neighborhood, it's worth its weight in gold.  You can save bundles of $$, since it's the guts that go, and the cases can be replaced, too, without spending the $$ on something new.

3.  Keep reading Critical Upgrades, the C34 tech wiki, and Maine Sail's website.

Like Ron says: "We can make the information available, but we can't make you read it!"   

I'll post back when I get the rebuilds back from John.

Thanks again, Chris.

[added to the Tech wiki bracket article]

[Stu Jackson]

Forward alignment.

[Stu Jackson]

#2

[Stu Jackson]

The new "case" fits between the ears without any shims.

[Stu Jackson]

ARGGH:

From another forum just today:

I've read numerous articles regarding the faulty bracket which secures the alternator to the engine. Ours is a 1987 M-25 which has the old bracket. I've since purchased the replacement parts which did not come with any instructions. I found a procedure on-line with photos to follow how to do the changeout. It seems a bit tedious. I'd like some input from some owners here. This seems to be rather important considering the potential damage which can occur. Should I proceed with this or ignore it and hope it doesn't happen to me? Some words of wisdom would be appreciated. We've had our boat for 14 yrs. The current bracket seems fine...SO FAR!

****************************

My reply:


I couldn't help myself ---

Yes, do it. What's your entire engine worth to you?

This includes a link to Maine Sail's excellent article, as well as to one I wrote back in 1999, when I had the bracket replacement ON MY BOAT, as yet uninstalled, and the old bracket broke!

Alignment is critical.

So is getting the correct pivot bolt and arm bolts for your alternator.

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

In my case, I did NOT have to remove the entire manifold, plus my studs were short but still long enough to hold the new bracket.

If you don't have to remove the manifold, it's a rather simple task.

I helped a good friend do his on his M25 on his E32. We had to remove the old studs on his, they were too short, but MS's article explains how to do that. URBAN MYTH: many say that you have to take off the manifold if you have to remove the old studs. Not true.

HERE'S ANOTHER REASON TO DO THIS:

I have a good friend with an M25XP. He neglected his raw water pump and it leaked all over his engine. He had to replace his oil pan. He also just learned his timing gear cover is shot, rusted though. Now here's the part that oughta interest you: they don't make these engines anymore. The timing belt cover is no longer available.

They are difficult, if not impossible to find.

So, WHEN, not if?, your alternator bracket fails catastrophically because it is a casting, and it RUINS your timing cover, you will have $7,000 to $12,000 to spend on a new engine.

All because it was too "tedious" to do four hours of work for a $200 replacement bracket.

Why people ask...

But, you and another Ericson owner have figured: "It's been working so far, why bother?"

Yeah, right...

Why ask?

For the past 25 years many, many skippers have been URGING other skippers to DO THIS.

We're not doing it 'cuz we feel better that you DON'T.

C'mon...

Please excuse me for my exuberance about this issue, but we have seen altogether too many skippers who have lost their entire engines because they didn't know about this issue. Now we're "exposed" to one who KNOWS it exists and is asking whether he should do it.

NAHHH, why bother???

************

Quite frankly, it is truly disappointing that folks, when warned, simply refuse to spend a short amount of time to avoid catatrophic failures.

[Stu Jackson]

Here's the improved alignment, compare it to the picture (of mine) included in Maine Sail's article.  Note the shims below the thermostat housing.

[Stu Jackson]

Two test cruises and it works just fine.

A lot less vibration, no belt dust, belt stays tight.  Could be that the ring terminals on the back of the alternator might stay on for a change! 

[Ron Hill]

Stu : I've always used self locking nuts when I connect ring terminals!!

A thought

[Stu Jackson]

Yes, Ron, so do I.  What broke, on ALL of the ring connectors made by the factory wiring harness that came with the regulator, was the electrical connection - the wire to the ring.

[KWKloeber]

Yes, Ron, so do I.  What broke, on ALL of the ring connectors made by the factory wiring harness that came with the regulator, was the electrical connection - the wire to the ring.

I know it's an old thread, but saw the link from Stu and noticed the note about the terminal wires breaking.   Just a FYI, JTSO, etc -- take if for what it's worth from experience/fabricating many a harness and then, YBYC.........

What I will NEVER, EVER do -- NADA, NIET, etc., is use a 'ring terminal' on an Alt or starter solenoid, etc., where there is flexure to the wire (i.e. the cable can't be tied down next to like, say, where it can be using a mounted terminal strip or buss bar, ESPECIALLY anything over a #6 ring.   They are IMHO, totally inappropriate for that use -- the metal ring body is WAY TOO LIGHT and eventually they WILL flx and cold-work-harden stress and eventually crack.  In fact also, if you crank down and tighten, say a 5/16" ring, you can actually twist the body of the ring right around.   

If you look at rings side-by-side, as the wire gets heavier and heavier (say, blue #6 post ring to a yellow 5/16" post ring, where the flexibility of heavier wire goes to the basement,) the ring body material "meat" decreases and decreases.  DUHHHHHHHHHH. STUPID, STUPID, STUPID.  Who would think of keeping the amount of "meat" at least CONSTANT for each size terminal?  Not ring manufacturers, they simply punch a larger hole.  Double DUHHHHHHHHH.







Instead, use a starter lug or a power lug (reference MaineSail's DIY site for the difference.)  The smallest avail, is 10 awg x #10 post (typically the size of the alt neg terminal; Alt + is typically a 1/4" post) but if you have a 10 awg charge wire, or a 10 awg harness power wire to the solenoid, strip it longer and just fold the strands back onto itself (effectively making a nearly identical 8 awg cir-mil wire, and crimp.  of course the alt + and - should be 8 awg or larger anyway, but...... ) 



Cover with MIL SPEC AHST so there's no flex point right behind the lug (don't use simple double-wall AHST.)  Just go w/ experience on this one and you will NEVER EVER have another issue with connections at those locations.  And of course use a boot on the exposed + terminals!!!