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Topic: How are your alt bearing's (Read 816 times) previous topic - next topic

How are your alt bearing's

Just a thought for you guys, on my Detroit 6/92 we have had it for 7 years and never a problem with the alternator so I decided to pull it and have it checked for brushes and bearing's. Got it back today and the shop said it looked good except for the bearings said they were dritty so he replaced them.
Better here at home then on the road.
So if your so inclined might be something to think over.
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: How are your alt bearing's

Reply #1 –
Definitely in same category as generator end bearing. So nice that the ISM alternator belt is optional
Scott

Re: How are your alt bearing's

Reply #2 –
Yup, alternator bearings fall into "it might be a good preventive maintenance" item.

And absolutely, anytime you remove a belt, rotate and check all the accessories it is driving.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: How are your alt bearing's

Reply #3 –
Quote from: Andy 2 –
Just a thought for you guys, on my Detroit 6/92 we have had it for 7 years and never a problem with the alternator so I decided to pull it and have it checked for brushes and bearing's.

Inexpensive when you do it that way, considering what a tow costs, not to mention a side of the road alternator.  Good Job!
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: How are your alt bearing's

Reply #4 –
Guilting me into replacing mine. 20 years old and 70k miles. It's not the mileage it's  the calendar that affects the lube. I'll put it on the to do list. Actually a great idea and much cheaper than ALL the other options. Already did the generator bearing. And it was at the first stages of failure. 700 something hours and 20 years old.
Scott

Re: How are your alt bearing's

Reply #5 –
Before Mexico, I will pull the alternator and take it to a local shop. They bead blast it, change bearings, etc for under $100. It's been almost 30 years so probably a good time. Cheap insurance. I did that on our old Buffalo bus for the starter. Again, cheap insurance.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: How are your alt bearing's

Reply #6 –
Yeah forgot to mention it was 110 bucks to have it done, and yes it sure makes for the time you might have to listen to dw about your maintenance schedule 😁 just saying 👍
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: How are your alt bearing's

Reply #7 –
With the generator bearing its the going down the road with the generator being
stationary is what is the hardest thing on the bearing. With the M11 if the bearings
seized up, at least we aren't stuck on the road. Still, checking bearings is a great idea.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: How are your alt bearing's

Reply #8 –
Wait a minute. After only 31 years I might need to proactively have the bearings on my alternator checked out? What's this world coming too? What happened to quality? Just kidding of course. And the way it's mounted on top of the motor sure easy enough to get to. On my winter to do list as of now.
Andy, Looking forward to seeing you again. Was in your neighborhood. when we went to the FMCA rally in Gillette WY but ran out of time otherwise you would have had to put up with me.

See ya in Quartzite!

Steve
The Starship- 1990 Grandvilla Unihome U300 40ft
6V92 Detroit Diesel w/ 4 spd Allison w/ retarder. Build# 3575 , Foretravel# 17895
The Shuttlecraft- 2015 Ford Explorer
Steve ( N6EKV ) & Lori ( N6JTD ) Faries  w/ Marlee our precious pup.
Patterson CA.

Re: How are your alt bearing's

Reply #9 –
Mine should be fine. MOT replaced the alternator this summer.

Re: How are your alt bearing's

Reply #10 –
Guessing most all our rigs carry a similar alternator?

Whomever goes at this first, How about post the Bearing numbers along with the model of the alternator.

A quick search for Leece Neville alternator bearing shows a 63054N to be a common value for many HD alts. BUT not saying that is the value for yours. Check your own model number.
https://store.alternatorparts.com/63054n-ball-bearing-double-sealed-for-delco-denso-ford-leece-neville-motorola-prestolite-heavy-duty-alternators.aspx

If your number is the above
Any sourced 25mm x 62mm x 17mm double sealed would fit the application, BUT STAY WITHIN THE SAME SERIES meaning 6305 in this case.. I commonly by all my bearings from
https://www.vxb.com/

FYI....if you dont have a bearing puller or small press, this is probably not in your ability to perform DIY.

 


thanks.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: How are your alt bearing's

Reply #11 –
Not saying the bearing replacement is a bad idea but remember the alternator will only be as strong as the weakest link.The
Delco 28s's are a great replacement.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: How are your alt bearing's

Reply #12 –
Nothing wrong with Leece Neville alternators. My FD specified only LN. Never any problem.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: How are your alt bearing's

Reply #13 –
Quote from: mkc1962 –
Guessing most all our rigs carry a similar alternator?

Whomever goes at this first, How about post the Bearing numbers along with the model of the alternator.

A quick search for Leece Neville alternator bearing shows a 63054N to be a common value for many HD alts. BUT not saying that is the value for yours. Check your own model number.
https://store.alternatorparts.com/63054n-ball-bearing-double-sealed-for-delco-denso-ford-leece-neville-motorola-prestolite-heavy-duty-alternators.aspx

If your number is the above
Any sourced 25mm x 62mm x 17mm double sealed would fit the application. I commonly by all my bearings from
https://www.vxb.com/

FYI....if you dont have a bearing puller or small press, this is probably not in your ability to perform DIY.

 


thanks.
Yes I would much prefer to have the replacement bearings in hand before removal. And if I knew what mine took would order today. Probably I should start with figuring out what is installed on my coach. I'm confident it is the original but that doesn't do me any good till I get a part number of it. Easy job if you have the tools, and cheaper to have it done if you don't. Alternator, starter rebuild shops still exist but are becoming harder to find. In regards to my starter I will just replace with the updated gear reduction starter. Affordable and preferred IMO
Scott

Re: How are your alt bearing's

Reply #14 –
Scott,

fuly agree, like parts in hand before starting. Took me 2 months to get all of the cooling systems parts in hand, ,but now that is done.

The one source listed many of the possible HD alternators model numbers out there. I myself when I had my Alt in hand last week while doing the cooling hoses, noticed a metal tag with the ALT model number on it, but did not give thought to this at that time so  did not write it down. Luckily I cleaned up and blew out years of built up dust and such build up around the cooling fins, as well as clean the casing and now can clearly read the label with a mirror. If I see mine is on that source list, will get myself a set coming to maybe do one day soon. At the moment no noises or lack of electrical efficency noticed on mine. But I had an alternator on one of my other cars, went from 1 week to the next with a service check all ok then a bearing failure. That one damaged the stator in the  process, so had to be replaced. As Alts for our coaches can be quite pricey, figuring a bearing, brush update is cheap PM.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: How are your alt bearing's

Reply #15 –
Alternator bearings just come from most common metric sizes but have different grades. Very few specialized bearings that may be more difficult to find. Good to have a metric caliper when measuring sizes.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: How are your alt bearing's

Reply #16 –
IF you are purchasing replacement bearing for your alternator, and they're $8 each don't.  Bearing come in precision classes which used to be ABEC 1-9 and may still be but ISO numbers start with P.  If you're replacing alternator bearings ABEC 5 or P4 are probably your best choice for long life.

The four digit bearing number is an industry standard, the first two digits being the bearing OD and the second two the ID and yes these are metric numbers. 62054N is 25mm by 62mm by 17mm.  That would be the 6205.  62 = 62mm ON, 05 = 25mm ID and the 4N I'm guessing is Ball Bearing, Double Sealed and a precision class suitable for alternator service.!!!

FWIW I purchased am $8 bearing for a machine I was building at PH Precision, and the owner said "You've made a mistake, this isn't expensive enough" and I responded "It's only and idler pulley."  Hah!  Didn't last a month in 14 hour 4 day a week service and got replaced with an ABEC5.


1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: How are your alt bearing's

Reply #17 –
I have been pressing and pulling bearing of all sorts and sizes for over 45 years, and yes there are some that used to be better than others. IM not too sure about that any more.. I do tend to stay with the higher end brands Nachi, SKF, National, NTF, Timken. But also many of the no name brands as well. I have seen failures in ALL of them. An observation I made about 20+ years back, after I had just replaced a set of Timken on an Ac Condensing fan motor.  Yes I remember this incident well as it was hell of a hot summer, and with the motor out we were without AC. Nobody local had the fan motor, but the bearings I was able to find at a local napa. I replaced them 1 saturday, and by the next saturday they were toast. Now these were some of the highest quality bearings one could find at the time, and Timken still is. So I pulled the bearings. There were of the 2RS (double sealed variety). Any double sealed bearing one can easily pop the seals with the point of a pocket knife or similar. What I found inside was basically zero grease. BOTH of these new timken bearings were the same situation, basically zero lubricant. I pulled them both, took them back to napa, upon seeing they gave me another set. Right there at the counter popped the seal on the new one, same situation. everybody shook their head at the situation. I took the new bearings, greased them myself, popped the seals back in and never had another problem out of that motor it lasting until I upgraded AC's about 5 years ago.
EVERY bearing I buy, that is sealed, and I don't buy any that are metal capped, I pop the seals, check the lubrication condition, add if needed and carry on. Since that time,  I have rarely found any that hold sufficient amount of lubrication. I am pressing 2 rather large Honda CRV front wheel bearings this morning. I popped the seals on those yesterday after they arrived, sure enough 1 near dry of lubricant, the other a bit more would not have hurt it.

Measuring to be sure is never a bad thing, But have rarely seen a bearing that does not have its specs stamped on to either the casing band or more commonly on the seal surface/both sides. Its numbers specify what type of bearing it is, its application and seal type. Those series of bearing also fall in to certain size ranges. In the case of the one I Mention and those numbers it is just coincidental that the 62 happens to be the same as the OD. See bottom of post for breakdown of bearing numbers.

I can see where my statement of size above may have been misleading. I edited that. If you have a 6305, you need to stay with a 6305. I have seen many suffix values, but in the case of this 4n not quite sure as that is not part of the bearings standards. Usually a value of 2 means both sides, and the letter is the type of seal. But have seen manufactures with odd values as well.

I have lost count of the amount of alternator, small motor bearings I have done in my lifetime. There is nothing special or high performance about them. Most if not all will be ball type, have seen a few metal cased though wouldn't recommend, and I dont think I have ever seen one that was a roller type, roller type are usually reserved for heavy shaft or oil submersed applications. If you stay with the same number bearing you are getting the proper specification for the application. An Alternator generates no more heat than any other electrical motor, Its RPM's are usualy 2-2.5 times that of the driven gear, not incredibly high.

Yes keep applications the same, never replace a ball with a roller or vice versa. I personally dont care for any that are single sealed or metal sealed, but there are unique applications for such that yes even a double seal would work for.

Yes you can buy high quality for $8 or $20. I have never had a properly lubricated bearing that was $20 outlast a $8.

Bearing replacement and application selection is not complicated, but it does takes some knowledge, and usually a few special tools. Anyone can do so, but do so with proper knowledge and skill-set. I would say leave it to the pro's....but I am of the school that most anyone can achieve anything they want to if they set their minds to it, learn good technique and obtain the proper tools for the job.

Lets use a 6902 as an example:
S            6902        2RS
^            ^^^^        ^^
Prefix    Code      Suffix

Prefix:

    K - Cage with roller elements
    L - Removable bearing ring
    R - Ring with roller set
    S - Roll body of stainless steel
    W - Stainless steel deep groove ball bearing

Code:

(6)902 - This first number relates to the bearing type, typically most bicycle bearings will be a "6" which is a "Deep Groove". Occasionally you will find a "7" bearing which is a "Single Row Angular Contact"

6(9)02 - This second number relates the bearing series, which reflects the robustness of the bearing. As you go up the scale below from 9 to 4 the inner and outer race thickness will usually increase along with the ball size, this will be to help cope with extra load.

    9 - Very thin section
    0 - Extra light
    1 - Extra light thrust
    2 - Light
    3 - Medium
    4 - Heavy

69(02) - The 3rd and 4th digits of the bearing number relate to the bore size of the bearing, numbers 00 to 03 have a designated bore size depending on the number.

    00 - 10mm
    01 - 12mm
    02 - 15mm
    03 - 17mm

*Note: Numbers over 03 simply have a bore size which is 5 times that of the 3rd and 4th digit.

Suffix:

    2 RS - Bearing with rubber seal on both sides. RS provides a better seal but more rolling friction than 2Z.
    RS - Bearing with rubber seal on one side, one side open.
    2 Z / ZZ - Bearing with a metal seal on both sides.
    Z - Bearing with a metal seal on one side, one side open.
    E - Reinforced Design
    P2 - Highest precision
    K - Bearing with taper bore



Mike in AL
2001 U295
8.3 ISC 350
Build 5918
 

Re: How are your alt bearing's

Reply #18 –
Fan belts adjusted too tight are also a cause of bearing failures. You should be able to use your fingers and rotate the belt 90 degrees midway between pulleys. Less means it's too tight. More means you need to tighten it.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)