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Author Topic: Mounting Leece Neville 8MR2069TA alternator on M35BC Engine  (Read 393 times)

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John Langford

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Mounting Leece Neville 8MR2069TA alternator on M35BC Engine
« on: August 04, 2017, 11:40:39 PM »

Has anyone done this? My present alternator is mounted on a heavy duty bracket attached to the block. The bracket looks like it is original (same paint as engine). It has two arms. There is a long bolt connecting the forward to the aft arm with a lock nut at the aft end. Between the two arms - in order, looking aft - there appears to be a washer, then the 1" spool of the alternator with its 1/2" mounting hole, and then some kind of long hollow spacer over the bolt. I can't provide a picture because it is obscured by the alternator.

 It is quite difficult to access the nut so I am seeking advice before trying to disassemble all of this and trying to fit the replacement alternator. One question is how does this arrangement stabilize the alternator? The diameter of the alternator mounting hole (1/2") is much larger than the diameter of the bolt.

I appreciate that this may not make a lot of sense if you can't see it. But if anyone knows how this works I would be grateful for some advice.
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KWKloeber

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Re: Mounting Leece Neville 8MR2069TA alternator on M35BC Engine
« Reply #1 on: August 04, 2017, 11:56:40 PM »

Is the TA your  current alternator, or a replacement?
I thought on the 35B, the stock alternator has a 2 inch foot, not 1 inch foot??
 The pivot bolt for the alternator is 3/8 inch, I would think that the stock alternator should also be the same.

Did you check the service manual to see if it includes anything on the alternator, or adjusting it?
« Last Edit: August 05, 2017, 06:38:49 PM by KWKloeber »
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mainesail

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Re: Mounting Leece Neville 8MR2069TA alternator on M35BC Engine
« Reply #2 on: August 08, 2017, 03:21:28 AM »

Has anyone done this? My present alternator is mounted on a heavy duty bracket attached to the block. The bracket looks like it is original (same paint as engine). It has two arms. There is a long bolt connecting the forward to the aft arm with a lock nut at the aft end. Between the two arms - in order, looking aft - there appears to be a washer, then the 1" spool of the alternator with its 1/2" mounting hole, and then some kind of long hollow spacer over the bolt. I can't provide a picture because it is obscured by the alternator.

 It is quite difficult to access the nut so I am seeking advice before trying to disassemble all of this and trying to fit the replacement alternator. One question is how does this arrangement stabilize the alternator? The diameter of the alternator mounting hole (1/2") is much larger than the diameter of the bolt.

I appreciate that this may not make a lot of sense if you can't see it. But if anyone knows how this works I would be grateful for some advice.

John,

Who did you buy this from?

Did you let them know it was for a 2" foot mount? The 8MR2069 takes a rather fancy shim/spacer that is difficult to find. The shaft is 17mm so you're only likely going to find Delco fit pulleys that have a bushed/raised area on the back side that needs to be machined off to match your offset..

I have shims and 3/8" pulleys but generally only sell them as a package with an alternator and I don't stock extras. I will dig around and see if I have any extras for my inventory count...
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John Langford

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Re: Mounting Leece Neville 8MR2069TA alternator on M35BC Engine
« Reply #3 on: August 08, 2017, 11:43:14 AM »

Thanks to both for replies and useful thoughts. Sorry for delay in responding; I was on the road. 

More information might help get to a solution. 

The existing alternator is a Leece Neville 8MR 105amp model with a 1" spool and apparently a hole size the same as the 2069 replacement.  As noted, there is presently a spacer over the 3/8" bolt to fill the space in OE mounting bracket. Assumedly that would work with the replacement. I have a pulley installed on the 2069 that is very close to the same OD as the existing alternator but can't tell at this point if the new pulley will line up when installed. I don't know the brand of the pulley but no machining was done to it prior to being fitted.

If all of the above makes sense I am still puzzled by two things. The head of the existing 3/8" mounting bolt is round and flush with (set into) the forward end of the mounting bracket. How then is it possible to tighten the nut on the aft end? Second, am I going to find some sort of spacer inside the 1/2" mounting hole of the existing alternator that can be used to stabilize the alternator on the 3/8" bolt? The alternator does not wobble.

Finally, I should have made it clear that I bought the 2069 as a replacement to be used if the either the Heart in charge regulator or the existing Leece Neville alternator went south while I was cruising. They are both working at the moment but they are both 17 years old and I like to be prepared.

Any further thoughts appreciated.
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Re: Mounting Leece Neville 8MR2069TA alternator on M35BC Engine
« Reply #4 on: August 08, 2017, 12:04:45 PM »

 It's probably a carriage bolt so you don't have a hex head  exposed. You may need to replace it with a hex head
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Twenty years from now you'll be more disappointed by the things you didn't do, than by the ones you did.
So throw off the bowlines.  Sail away from the safe harbor.  Catch the tradewinds in your sails.
Explore.  Dream.  Discover.   -Mark Twain
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