I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley and
modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length. (They
kept trying to offer me narrower belts while I knew my vee pulleys were
intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates. The
computer system had brought one in from each near by store (each store only
stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask for
4 belts since I was confident that these would most likely be from the same
mfg batch. Never happened, even though they did come from the warehouse, of
the 4 belts, only 2 were the exact same length. The remaining 2, again,
don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never carries
it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use special
stock number designation to require that they be from the same batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts to
ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions

In article ,
"Steve" wrote:

I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley and
modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length. (They
kept trying to offer me narrower belts while I knew my vee pulleys were
intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates. The
computer system had brought one in from each near by store (each store only
stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask for
4 belts since I was confident that these would most likely be from the same
mfg batch. Never happened, even though they did come from the warehouse, of
the 4 belts, only 2 were the exact same length. The remaining 2, again,
don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never carries
it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use special
stock number designation to require that they be from the same batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts to
ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions



Did you try Hatch & Kirk in Seattle????


Bruce in alaska
--
add a 2 before @

Cars don't use matched v-belts, therefore, you can't buy them at an
auto parts store. You need to go to a power transmission products
distributor such as Applied Industrial (formerly Bearings Inc.).
Matched belts are sold as a measured, matched set. Just buying two
with the same lot number doesn't mean they match.

"Steve" wrote in
:

Note: I don't have an accurate way to actually measure belt lengths
but I install a pair, and measure the belt deflection while tensioned.


Will it make any difference having been stretched to the same length after
a few months on the pulleys under pressure? They'll both end up the same
length in the end....stretched to fit.

Serpentine belts would be better?

Brian W

On Tue, 29 Mar 2005 09:15:37 -0800, "Steve" wrote:

I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley and
modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length. (They
kept trying to offer me narrower belts while I knew my vee pulleys were
intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates. The
computer system had brought one in from each near by store (each store only
stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask for
4 belts since I was confident that these would most likely be from the same
mfg batch. Never happened, even though they did come from the warehouse, of
the 4 belts, only 2 were the exact same length. The remaining 2, again,
don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never carries
it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use special
stock number designation to require that they be from the same batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts to
ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions

Not sure what size belt you are using but an A type belt used on fan motors
work well . A good friend of mine used A belts on his stock car because car
belts kept flying off .
"Brian Whatcott" wrote in message
...
Serpentine belts would be better?

Brian W

On Tue, 29 Mar 2005 09:15:37 -0800, "Steve" wrote:

I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley
and
modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length.
(They
kept trying to offer me narrower belts while I knew my vee pulleys were
intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates.
The
computer system had brought one in from each near by store (each store
only
stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask
for
4 belts since I was confident that these would most likely be from the
same
mfg batch. Never happened, even though they did come from the warehouse,
of
the 4 belts, only 2 were the exact same length. The remaining 2, again,
don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the
belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry
the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never
carries
it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use
special
stock number designation to require that they be from the same batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts
to
ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions

Detroit Diesel uses a doube 1/2" belt that is actually molded into one.

Yeah, two belts in one. you can't get much more matched than that.
You might check with a dietroit diesel dealer and see if they can come
up with the size you need.

Tim

You need Gates V80's. All are made to high tolerances so any set you get in
that series will match. See:

http://www.gates.com/brochure.cfm?br...ocation_id=559

I use green stripes.

--


Keith
__
You can sleep in a trawler; you can't cruise in a house.
"Steve" wrote in message
...
I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley
and modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length.
(They kept trying to offer me narrower belts while I knew my vee pulleys
were intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates.
The computer system had brought one in from each near by store (each store
only stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask
for 4 belts since I was confident that these would most likely be from the
same mfg batch. Never happened, even though they did come from the
warehouse, of the 4 belts, only 2 were the exact same length. The
remaining 2, again, don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the
belt wear that results for unmatched belts. These guy incorrectly assumed
that the tighter belt would wear faster and eventually both belt would
carry the load. While, in fact, (as I understand it) the looser of the 2
belts wear due to it's slippage and just get larger due to this wear and
never carries it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use
special stock number designation to require that they be from the same
batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts
to ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions

And while on the subject of v belts, be wary of pulley sizes if you are
tempted to try kevlar belts. There is a minimum pulley diameter (3.25 inches
for A section, IIRC) below which a kevlar belt will quickly destroy itself.
I had two straight failures before I was able to get that little bit of info
from the manufacturer.

"Steve" wrote in message
...
I just upgraded my Volvo MD2B diesel alternator from 35amp OEM to a Delco
120 amp.

The OEM set up had only a single vee groove pulley and belt.

I made a new engine double vee pulley to match the new alternator pulley
and
modified the adjusting bracket.

Next I went to the local auto parts store (large local chain) to begin my
search for the correct belt size. My range of adjustment was limit due to
the much larger case size of the new alternator. Through trial and error
(many trips back to the boat), we established the correct belt length.
(They
kept trying to offer me narrower belts while I knew my vee pulleys were
intended for 1/2" 38 degree.)

I then ask them to take back the one 'correct' belt they had in stock and
order me a "matched pair" of that size/part number. The next morning I
picked them up and it was obvious they weren't matched. I didn't even have
to look at the mfg production numbers, even though they were both Gates.
The
computer system had brought one in from each near by store (each store
only
stocked one of this size).

Next we tried ordering them from the main warehouse and this time I ask
for
4 belts since I was confident that these would most likely be from the
same
mfg batch. Never happened, even though they did come from the warehouse,
of
the 4 belts, only 2 were the exact same length. The remaining 2, again,
don't even come close.

Note: I don't have an accurate way to actually measure belt lengths but I
install a pair, and measure the belt deflection while tensioned.

Something that these auto parts people don't seem to understand, is the
belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry
the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never
carries
it's share of the load.

During my 23 year in navy ships, our matched belt needs were supplied as a
bundled set with batch number markings. When ordering, we had to use
special
stock number designation to require that they be from the same batch.

I suspect I will have to go to a supplier of "Industrial" equipment belts
to
ever avoid this problem in the future.

Has an one else ever been through this??

Thanks,

Steve
s/v Good Intentions

"Larry W4CSC" wrote in message

Will it make any difference having been stretched to the same length after
a few months on the pulleys under pressure? They'll both end up the same
length in the end....stretched to fit.


Since you didn't read ( don't agree with) the last part of my original post,
I will cut and past it he

"Something that these auto parts people don't seem to understand, is the
belt
wear that results for unmatched belts. These guy incorrectly assumed that
the tighter belt would wear faster and eventually both belt would carry the
load. While, in fact, (as I understand it) the looser of the 2 belts wear
due to it's slippage and just get larger due to this wear and never carries
it's share of the load. "

Steve
s/v Good Intentions