LumberJocks

Powermatic 68 ..Looking for a pulley

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by jbay posted 06-07-2017 02:53 AM 1050 views 0 times favorited 14 replies Add to Favorites Watch
View jbay's profile

jbay

1861 posts in 739 days


06-07-2017 02:53 AM

Does anybody know of a good source where I can get a 3 belt/groove pulley that goes onto the motor?
Someone put a 2 belt pulley on it and I would like to correct it.
Thanks in Advance for any help.

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.


14 replies so far

View AlaskaGuy's profile

AlaskaGuy

3662 posts in 2149 days


#1 posted 06-07-2017 07:34 AM

A quick Google search to all the usual place come up as discontinued. Apparently the part# is 3717060. It’s a 7/8 bore.

I have an old Delta Rockwell 12-14 saw with a 3 grove pulley. Several years back I broke one of the belts. Never got around to replacing it. Honestly I can tell the difference in performance.

Personally I would mess with it if it’s a big hassle. Maybe a bearing/transmission shop could help.

-- Alaskan's for Global warming!

View jbay's profile

jbay

1861 posts in 739 days


#2 posted 06-07-2017 01:42 PM

Thanks
The pulley on it now has wider grooves than the arbor pulley, and is offset about 1/2”
Right now the pulley is flush with the shaft. To align the belts I would have to hang the pulley off of the shaft that 1/2” which I could, but don’t really want to. That will be plan B if I can’t find an aftermarket pulley to work.
I appreciate you taking the time to look that up for me.

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View jbay's profile

jbay

1861 posts in 739 days


#3 posted 06-07-2017 03:30 PM

Just got the motor out. Visual measurement of the shaft.

I’m thinking someone must have changed out the motor some time down the line.
I thought these came with 5hp motors?

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View runswithscissors's profile

runswithscissors

2565 posts in 1865 days


#4 posted 06-09-2017 04:14 AM

Applied Technologies has gobs of pulleys. Google them.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

View jbay's profile

jbay

1861 posts in 739 days


#5 posted 06-09-2017 01:29 PM

Thanks,
I googled them.
So far the only pulley’s I have been able to find are the type that require a bushing.
Any of the other fixed bore pulley’s (11/16 – 3/4” bore) only go up to 2 grooves.
Thanks for the site.

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View magaoitin's profile

magaoitin

246 posts in 789 days


#6 posted 06-09-2017 05:58 PM

Tricky…
I know it is probably a silly question, but have you tried searching Marathon's website for an authorized service shop near you? They could decode the model number and probably know where to find the pulley that fits that shaft.(heck they probably even have one on the self)

There are 2 commercial electric motor repair shops by me (Tacoma Washington) that have been an amazing resource for my “vintage” Powermatic 60. I have the original 1952 motor in mine and it has a 3/4” shaft like yours. (Mine is a 2 belt.)

First is Center Electric and the other is Electric Motors Service and Controls. Center Electric is a Marathon repair shop too.

You probably have a local electric motor repair place that does commercial rebuilds on small motors and skip the shipping, but its worth a phone call.

I don’t see a frame number on that badge, just the model number. I am going out on a limb and would say it is older than 1952? That might be the tough part for finding the part you need. A marathon motor repair shop would need to search that motor’s model number to match up the pully…if one exists. Since it is not the original motor, and it looks fairly old it might not be made anymore.

-- Jeff ~ Tacoma Wa.

View jbay's profile

jbay

1861 posts in 739 days


#7 posted 06-09-2017 06:09 PM

Thanks Jeff,
I’ll check them out. There is one service center on Marathon’s list that I may try.
I appreciate your time.

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View MrUnix's profile

MrUnix

6017 posts in 2039 days


#8 posted 06-09-2017 06:50 PM

What is the O.D. of the pulley? It obviously isn’t the original motor, which had a 7/8” shaft, so the PM replacement won’t be applicable – and being specific to the PM, I seriously doubt Marathon would have anything applicable. There are a few places you can find multi-belt sheaves with a 3/4” finished bore though, such as motion industries. – But you will need to find a matching one with the same O.D. or the speed at the arbor will change.

In reality, two belts are fine. If it’s working well as it is, I’d just leave it alone and make sawdust.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View jbay's profile

jbay

1861 posts in 739 days


#9 posted 06-09-2017 07:04 PM

The OD of the existing pulley is 3”, same as the arbor pulley.
I’m going to check a few more places first but if nothing comes up I will start making sawdust.
Thanks

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View AlaskaGuy's profile

AlaskaGuy

3662 posts in 2149 days


#10 posted 06-09-2017 07:44 PM

In my first post I said “Honestly I can tell the difference in performance.” That should have said ” “Honestly I can’t tell the difference in performance.”

-- Alaskan's for Global warming!

View MrUnix's profile

MrUnix

6017 posts in 2039 days


#11 posted 06-09-2017 08:30 PM

The OD of the existing pulley is 3”, same as the arbor pulley.
- jbay

That doesn’t sound right and apparently a PO just slapped on whatever they could find. The original pulley (P/N 3717060 – same as used on the PM66 IIRC) should be 3.4” in diameter. With a 3” pulley on both the motor and the arbor, the 1:1 ratio makes the blade spin at motor speed (3450 rpm). The arbor should be spinning closer to 4000 rpm. With a 3.4” motor pulley and a 3” arbor pulley, that makes it ~3910 rpm. The manual for the PM68 states the maximum SFM for a 12” blade is 13,000… with the 3.4”/3” combo, that puts it at 12,277 SFM. You could actually go with a 3.5” pulley, which might be easier to find, which puts it at 12,639 SFM (or ~4025 rpm). With the 3”/3” combo, it’s only 10,833 SFM.

Just saying :)

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View jbay's profile

jbay

1861 posts in 739 days


#12 posted 06-09-2017 08:52 PM



In my first post I said “Honestly I can tell the difference in performance.” That should have said ” “Honestly I can t tell the difference in performance.”
- AlaskaGuy

I figured that ;)

Thanks Brad,
What do you think about a 3 3/4 pulley along with using a bushing?

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

View MrUnix's profile

MrUnix

6017 posts in 2039 days


#13 posted 06-09-2017 08:57 PM

Thanks Brad,
What do you think about a 3 3/4 pulley along with using a bushing?
- jbay

That might be a bit too much… it would result in a SFM on the blade of ~13,541 (~4313 arbor rpm), which is over the stated max speed in the manual.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View jbay's profile

jbay

1861 posts in 739 days


#14 posted 06-09-2017 09:01 PM



Thanks Brad,
What do you think about a 3 3/4 pulley along with using a bushing?
- jbay

That might be a bit too much… it would result in a SFM on the blade of ~13,541 (~4313 arbor rpm), which is over the stated max speed in the manual.

Cheers,
Brad

- MrUnix


Thanks,
I’ll keep looking. What’s your opinion using the pulley and bushing combo?

-- If anyone would like to see my Portfolio, PM me and I would be glad to send you the link.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com