Catalina 34

General Activities => Main Message Board => Topic started by: Stu Jackson on July 30, 2009, 04:12:09 PM

Title: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on July 30, 2009, 04:12:09 PM
Recently, Stewart Napoleon, Hull #1472, Desiree, posted his experiences with oil in his engine, here:  http://c34.org/bbs/index.php/topic,5073.0.html (http://c34.org/bbs/index.php/topic,5073.0.html)

I want to take this opportunity to say a great big THANK YOU to Stewart for his topic because it MADE me look EXTREMELY carefully at my engine and its parts.

What I found was a MAJOR crack in the casting of my alternator.  I discussed it with Harv at Blue Circle and just shipped it back to him today.  I'll keep you posted on what happens.  I'd been having trouble keeping my alternator belt tensioned, and with Stewarts' experience in mind, looked very, very carefully at everything.

The second picture is of the engine room, where a simple once over visually would most likely NOT have found this.  Believe me, I almost used a microscope! :D

Lesson Learned:  ONLY YOU can care enough about YOUR OWN engine to find these kinds of things.  There is no magic boat mechanic good enough to care enough about YOUR engine than YOU!!!  And there's no manual written about this...the alternator didn't even come with a wiring diagram! :D
Title: Re: Careful Engine Inspection
Post by: Ron Hill on July 30, 2009, 06:06:04 PM
Stu : Good Point !!
Looking at your #2 picture (enlarged) of the engine compartment.  I don't see any washers/spacer (the same diameter as the alternator casting or larger) to take up the space between the bracket on the alternator and the aft bracket that holds it on the engine!!!  It almost looks like the bolt is bent. 
That space must be filled or you'll get compression on the engine bracket when you tighten that bolt.

At least you didn't meet your "Waterloo" like Stewart did.   A thought
Title: Re: Careful Engine Inspection
Post by: Stu Jackson on December 03, 2009, 01:04:43 PM
Another good link re this topic is the Alternator Belt Tensioner FLIX topic (http://c34.org/bbs/index.php/topic,3667.0.html (http://c34.org/bbs/index.php/topic,3667.0.html)), where I just included this 2001 discussion on page 3:

http://c34.org/bbs/index.php/topic,255.0.html (http://c34.org/bbs/index.php/topic,255.0.html)

I have my new alternator in hand, just got authorization from my doctor to put weight on left leg, so will install it soon and get back to sailing! 

:clap AND  :thumb:
Title: Re: Careful Engine Inspection
Post by: Stu Jackson on June 27, 2012, 11:42:20 AM
The C34 Tech wiki on the alternator bracket repair has been updated (Oct. 2011) [http://www.c34.org/wiki/index.php?title=M-25_Alternator_Mount_Conversion_Kit_%22B/M_256891%22 (http://www.c34.org/wiki/index.php?title=M-25_Alternator_Mount_Conversion_Kit_%22B/M_256891%22)] to note that the bolts used should be metric, not SAE.  

I attribute the failure of my alternator casing to the wrong bolts.  

I was able to procure metric bolts at a local hardware store.

I recommend you check your alternator if you've updated the bracket on your M25 engine.  If you have the smaller (thinner) SAE bolts, they'll allow your alternator to wobble.  A LOT.  It contributes to belt wear even if you think you've lined up the pulleys, and lets the alternator droop and lose belt tension.

I've added a link to the wiki to the C36 Forum that shows pictures of the different bolt sizes.

I also included the full text of the wiki about the metric bolts here:  http://c34.org/bbs/index.php/topic,7005.0.html (http://c34.org/bbs/index.php/topic,7005.0.html)

It says:  

October 2011 - From E. Herlihy an O'Day 35 owner: Last November (2010) I installed the upgraded Alternator mounting bracket, with the kit available through Torrensen Marine, and while I was at it I installed a new Leece-Nevile / Prestolite 90 amp alternator on my Universal M25. If you are reading this far, you probably know that the new alternator uses EXACTLY the same housing as the old 55 amp Motorola. BTW the kit is now ~$180.00 When I opened the box containing the kit, I was happy to see that it included all the parts, including the Alternator mounting bolts. I did the installation using the new bolts, but noticed that they did not seem to fit perfectly. The SAE Grade 5 pivot bolt allowed "a little" play of the alternator, and the tension bolt never seemed to fit "right." At the time I assumed that the alternator was machined so that the bolt would jam, thus preventing the bolt from loosening. The real reason is embarrassing....

I thought it strange that both of these bolts, and the nut were SAE. 031555 - 5/16NC x 1 031615 - 3/8NC x 3-1/2 031762 - Nut 3/8-16 Hex Steel Zinc

However, EVERY other fastener is Metric. I assumed that Torrensen would know and include the correct bolts, however the extra play was because the bolts did not fit... you know what happens when you ass-u-me... The Pivot bolt SHOULD BE a Metric M10 fastener. The tension bolt (connects the tension arm and the alternator) SHOULD BE a Metric M8 coarse thread. I realized this because I was getting a little belt dust on the engine. After only 50 hours this summer, I thought that was unusual, or I would need to buy a lot of belts. In October of this year (2011), I checked the alternator tension, and the "little" play seemed a "little" worse than it should have...

Because by now I had stripped some of the threads with the bolt that was included with the kit, I purchased a slightly longer bolt, a nut, and lock washer to use as a tension bolt. I also replaced the pivot bolt with a slightly longer M10 Fine thread bolt. It fit perfectly (no play at all). I used 2 nuts and a spring washer to jam the pivot bolt, so that it will not vibrate loose. I can't speak to the kit available through Catalina Direct, but the Torrensen kit has the wrong bolts!

Lesson 1: If the components in the "kit" don't seem right to you, they are not. Lesson 2: DO NOT USE THE ALTERNATOR MOUNTING BOLTS INCLUDED IN THE TORRENSEN KIT if they are SAE, and you have a Leece-Neville or Motorola Alternator.
Title: Re: Careful Engine Inspection & M25 Alt. Bracket Bolts
Post by: Ron Hill on June 27, 2012, 01:23:39 PM
Guys : While Stu is on that topic, I wrote a "Tip" long ago that needs to be repeated. 

On the M25XP and the M25 with the alternator modification (adjusting arm under rather than over the alternator) the two bolts that hold that arm are short bolts.  The holes that these bolts screw into are threaded all the way through.  So why not get a longer bolt (by about 1/2") and have more threads holding the alternator and arm in place!!   A thought
Title: Re: Careful Engine Inspection & M25 Alt. Bracket Bolts
Post by: Les Luzar on June 28, 2012, 09:28:07 AM
I have never really looked that close at my alternator bracket. I am going to inspect it closely this weekend to see if I have a spacer or not! Just for fun!
Title: Re: Careful Engine Inspection & M25 Alt. Bracket Bolts
Post by: mainesail on June 30, 2012, 06:20:34 PM
Guts don't feel bad the Universal engines are not the only ones that have improperly sized pivot bolts. MANY factory engines including Yanmar, Volvo/Perkins and Universal often ship with the wrong sized bolt for the alternator to pivot on. With a 35A alt this is rarely a problem but when you go to 80A+ it quickly becomes belt dust bonanza.. Universal also shipped a number of engines where the Motorola alts had SAE holes and yet others with metric, go figure. The alt bracket upgrade, IMHO, is a rube Goldberg fix and rather poorly engineered, but still far better than the original.

Please be aware that the long alternator 3/8" bolt that comes with the kit is most often the WRONG size. It is much to sloppy a fit in the bracket. The hole in the bracket works MUCH better with a metric bolt. I replace it with a metric bolt and occasionally need to then drill the alt to the proper fit. The problem is the Motorola alts shipped in both metric and US sizes over the years. The upgrade bracket is drilled for metric but Westerbeke ships a 3/8" bolt.. Belt issues with the new bracket are often due to the sloppy incorrect bolt Westerbeke supplies. It allows the alternator to "cock off" and create uneven belt wear and creates wear on the alternator foot mount.

Also the new bracket has oval holes for a reason, but every one I have seen installed has never taken advantage of them. You may not need to but you really should align the bracket fore/aft on the motor so the belt is in proper alignment.. This may mean spacer washers under the thermostat end of the mount. The one I just did required two metric washers to shim it forward..

Sloppy Fitting Westerbeke Bolt
(http://www.pbase.com/mainecruising/image/141029501.jpg)

A much better fit:
(http://www.pbase.com/mainecruising/image/141029500.jpg)

New bolt on left, Westerbeke supplied "sloppy" bolt on right:
(http://www.pbase.com/mainecruising/image/141029502.jpg)

Forward Align
(http://www.pbase.com/mainecruising/image/141029503.jpg)

If you forward align place shim washers in the space:
(http://www.pbase.com/mainecruising/image/141029508.jpg)

Aft Align:
(http://www.pbase.com/mainecruising/image/141029505.jpg)


To Ron's point about the adjusting arm bolts, which is a good one, I go one step further.

I get a real long bolt, split washer and nyloc nut. I then adjust the arm and tighten the bolts hard. Once tight I install the "locking" nuts. I've yet to have one vibrate loose after this fix..

Alternator Ear End (gets both split washer and nylock nut. If the alt over heats it could melt the nyloc feature.)
(http://www.pbase.com/mainecruising/image/143848926.jpg)
Slotted end of adjusting arm: (this should never get hot enough to melt the nyloc if it does you have bigger issues.)
(http://www.pbase.com/mainecruising/image/143848927.jpg)

Title: Re: Careful Engine Inspection & M25 Alt. Bracket Bolts
Post by: Stu Jackson on June 30, 2012, 07:43:19 PM
New bolt installed today.

What a difference!

Pictures:

Crack in SECOND alternator.  Alternators should last longer than this one (2004 to 2009) when the first crack appeared, and from (2009 to 2012) BUT I was NOT sailing for most of 2009 and 2010 'cuz of my broken leg).

The small 3/8" inch bolt is, as Maine Sail notes, totally INADEQUATE to support the WOBBLE of the alternator.  The M10, 100 mm, bolt is very noticeably stronger.

Please check your bolts if you have an M25 engine with the alternator bracket upgrade kit.

Please also check if you have an M25XP.  Wouldn't hurt, eh?

This picture shows the start of the same kinda crack as pictured above with the previous alternator.
Title: Re: Careful Engine Inspection & M25 Alt. Bracket Bolts
Post by: Stu Jackson on June 30, 2012, 10:21:34 PM
Alternator belt sources

NAPA is a GATES belt.  Read the back of the packaging.

for 'no worries': I've changed the subject of this topic at least three times, to make it more meaningful.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts
Post by: Ron Hill on July 01, 2012, 12:45:54 PM
Guys : Stu is correct about Gates making the NAPA belts, BUT:

The NAPA dealer wanted $15 + while the auto store that stocked Gates wanted $8 + !!!

Your choice!!  

Also that bolt holding the alternator should NOT be stainless (for extra the strength).

A few thoughts
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts
Post by: Stu Jackson on August 07, 2012, 09:30:04 AM
Put the new alternator on yesterday.  The new pivot bolt was in.  The top bolt was a 5/16" by 1 1/4", didn't have enough length in the back to add the nylock.  The longer 5/16" bolts (1 1/2") did not have threads along the entire length and wouldn't work, so used Ron's "longer bolt" method.  A regular nut may work, we'll see.  The bottom alternator bolt was an M8 long enough to install a lock nut and nylock.

The belt stays tensioned now.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts
Post by: Stu Jackson on August 11, 2012, 06:01:41 PM
The belt stays tensioned now.

NOT!!!  Drats.  More investigation tomorrow.  I couldn't get a nylock on the adjusting bolt, too deep, will try a regular nut with a lock washer.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Ken Juul on August 12, 2012, 06:55:53 AM
Stu it may be that the new belt has stretched.  I'd re tighten and try again before re-engineering.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 12, 2012, 08:25:05 AM
Ken, thanks, the belt had been lightly used, but I will do so.  No re=engineering, just implementing Maine Sail's suggestions on the "nut & bolts."  :D
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 12, 2012, 04:46:03 PM
The 1 1/4" lag bolt didn't work because the shank didn't have threads all the way.  The 1" lag bolt was too short.  So I bought a 1 1/2" screw, put a washer on the front and a lock nut and regular nut on the back.  So far, so good.

This is the 1 1/14" lag with the 1 inch lag.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: 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.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 12, 2012, 04:56:57 PM
The screw w/ washer in front, nut and lock washer aft.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: mainesail on August 12, 2012, 05:06:23 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? :shock: 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.....
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Ron Hill on 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
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on 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?"  :D  Heck, the "KIT" didn't come with much of anything, re" washers...oh, yeah, lock nut & washer (standard!).  :D
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: mainesail on 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...
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 12, 2012, 06:29:51 PM
Will do, I love my ratchet set!  :D
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 29, 2012, 04:59:05 PM
You're right, the screw didn't work.

How's this?
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Ron Hill on 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
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: 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?
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: mainesail on August 29, 2012, 06:45:06 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.

(http://www.pbase.com/mainecruising/image/141029503.jpg)
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on 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. 
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: mainesail on 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.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Ed Shankle on 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
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on 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...
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 30, 2012, 05:57:44 PM
more
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Ron Hill on August 30, 2012, 06:09:13 PM
Stu : I assume that you have the alignment that you want!? 
If that's the permanent solution I'll quote Mainsail, "You must be joking"?!  Nylon is soft/especially when heated it's pliable and will NOT hold up in that environment!!!
  
I'd go to a machine shop and get a metal spacer made OR get a stack of metal washers to replace those nylon gidgets you inserted.
 
Also Nylon is compressible and you want something solid to really hold down that alternator in place solidly as the engine vibrates!!
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 30, 2012, 06:31:44 PM
I hear ya.  I'll keep an eye on it.  I'll get my son to help do it with metal washers.  All of the above.
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: mainesail on August 30, 2012, 07:33:02 PM
more

Stu,

Those shims would go well with one of those big red rubber bands from a punchy balloon, as your fan belt.... :D :D :D :D :D :D Please tell us they are temporary....
Title: Re: Careful Engine Inspection & M25 Alternator Pivot Bolts & Tension Nuts
Post by: Stu Jackson on August 31, 2012, 09:26:45 AM
Yes, they are temporary.