1998 V70 Alternator Bearing Rebuild Thread

[yanga001]

Hi Everyone,

My alternator has been noisy for a while now and the rebuild target has sat on a desk for about 4 months now. The goal is to rebuild the spare as i know the voltage regulator and diodes are good on my current one and on the spare. The problem is the whine and whirl that comes from the alternator. My car has a few things on the radar in terms of work to be done however it is a nice thing to keep me busy.

Anyways, following current recommendations i have been spec'ing SKF based bearings however i noted that the standard "6203-2RS" recommended in most places did not match up to SKF's naming scheme.

From what i gather, the front bearing needs to be a 6203 in terms of series and fit. The 2RS seems to be modeled and denote different things depending on the manufacturer.
SKA does not have a vanilla 6203-2RS but labels them with a few extra letters. Price wise, differences seem to come from the number of seals on the bearing and some frictional characteristics.

Now i know a basic remanufactured seems to set one back 100-200 dollars however i also was told these remans are not the bees knees. Therefore i would rather do the work and replace the bearings to get a little bit of a quieter ride.

The hotlist for the front bearings in order of assumed quality are detailed below:
-https://www.bearingscanada.com/6203-2RS ... gIapfD_BwE
Native 6203-2RS by VXB 8.73

https://www.qualitybearingsonline.com/6 ... 40-x-12mm/
SKF 6203-2RSL low friction seal on both sides 16 $

https://www.qualitybearingsonline.com/6 ... 40-x-12mm/
SKF 6203 2RSH/C3GJN
has grease rated from -30 C - 150C with seals on both sides 22$ C3 tolerance rating

Now i am a little convinced i am overthinking this, however i was wondering if anyone had answers for these questions:
-does it matter if its a double seal or single seal (my money is on double being better but idk)
-will a c3 tolerance be acceptable for the alternator? (seen mixed things on people using native 6203-2RS versus some using c3 tolerances)
-cost wise 6-10 $more on a bearing does not concern me too much as long as i can ensure the bearings will not go out again

For the rear bearing recommended as a 6303-2RS i found the following:

https://www.qualitybearingsonline.com/6 ... 47-x-14mm/
SKF 6303-2RSC3GJN $29
same idea with the grease, c3 tolerance, sealed both sides

https://www.qualitybearingsonline.com/k ... -12x37x12/
Koyo 6303-2RS (heard to stay away from Koyo) 13$

https://www.qualitybearingsonline.com/6 ... 47-x-14mm/
SKF 6303-2RS C3 13$ the close one with slightly higher tolerances ie C3

The SKF is rated for higher RPM which really is not necessary for my purposes on the NA boat. However, if wear wise it makes a difference over a 5 year period then an extra 16$ now means nothing compared to having to open up the alternator again.

In addition to this ill be grabbing a generic bearing puller for the procedure.

I look forward to any input on this.

[454cid]

Following!

I think I'd take a look at what's actually in the alternator that you're going to rebuild assuming it's an original Volvo supplied alternator, and not a re-manufactured unit. That's also assuming you're satisfied with a factory original level of longevity, and don't feel the need to try to exceed it.

[yanga001]

Yea I’ll take apart the spare over the next few days to see what they normally use. I am satisfied with the current longevity of it means I get a few years out of the alternator. I like to upgrade some things so the fancier bearings reflected that mentality.

[yanga001]

Started the teardown today, will add all photos at end, however i got the rear off the alternator.

The rear bearing is a Nachi 6203NSE2.

It is a japanese bearing and it has a blue seal while modern ones have the red seal so it appears to be oem.

I might toss the frame in an ultrasonic cleaner to make it shine. There is a decent amount of surface rust inside however i want to be careful to not short out the coils on one another.

Will tackle the rest of it next weekend it seems.

[yanga001]

https://www.bearingscanada.com/6203-2NS ... 012-c3.htm seemingly similar spec link for replacement nachi

[454cid]

I might toss the frame in an ultrasonic cleaner to make it shine. There is a decent amount of surface rust inside however i want to be careful to not short out the coils on one another.

The field coils can't be removed? I would be very hesitant to put the coils into an ultra sonic cleaner, for fear the wire coating would come off.

I just ordered a voltage regulator for my alternator, but I'd really like to rebuild the whole thing.

[yanga001]

I might toss the frame in an ultrasonic cleaner to make it shine. There is a decent amount of surface rust inside however i want to be careful to not short out the coils on one another.

The field coils can't be removed? I would be very hesitant to put the coils into an ultra sonic cleaner, for fear the wire coating would come off.

I just ordered a voltage regulator for my alternator, but I'd really like to rebuild the whole thing.

I would not toss the coils nor stator into it, however the frame is dark from grease accumulation.

Need to find the proper philips to hopefully not strip the 4 philips on the front of the frame.

Might get a new slipring too.

[yanga001]

Got some time today to work on it. Removed the inner coil by hammering the pulley with the bolt on it. Stripped the threads a little on the pulley but it still workable. Tossed both outer frames in a soapy ultrasonic cleaner. The Pozzidrive screws are just satanic and started to strip with the correct driver. I am tempted to drill it out and replace the screws with a nut and bolt. Ill check clearances, but it was a hell of a lot easier to tap out the shaft from the front plate then trying to remove the screws.

I am getting the sense that rebuilding alternators may not be something that is cost effective for a one off. However, i do believe the bearing replacements are an easier way if and only if those 4 pozzi screws were gone...

Slip ring is a bit worn out, however it will probably last for the duration of this vehicle.

Will put all the photos in one post once this is concluded.

[scot850]

I am finding this thread very interesting. Thanks for updating us.

Neil.

[abscate]

I am getting the sense that rebuilding alternators may not be something that is cost effective for a one off.

It’s great too go through these experiences, and you learn a lot doing them. Sometimes this realization is priceless.