1998 V70 NA RMS rear main seal - pull engine? Anything else while there?

[Andrew Vanis]

1998 V70 NA 230k mi

Pretty sure the RMS is leaking (pics below) driver's side of center.

1) is there a way to confirm that it is the RMS or could it be something else? Maybe dye or pressurizing the oil system? And does it matter since that something else would require the same service procedure as the RMS?

2) is this 850 engine and transmission removal topic and PDF to the best how to for the V70?

viewtopic.php?f=1&t=28973

2.1) is engine/trans removal still the preferred way to repair a RMS leak?

3) what else to do while I do this leak repair? Take the view as-if the car has not received any periodic maintenance.....I'm thinking:

PCV system
Motor mounts if showing wear

What else?

Thanks
Andy

[Sveedy]

You could just remove the engine, and leave the trans in place. That's the way I went. Didn't have to fool with the axles that way.

[jmartin919]

At 230K would it not make sense to have someone go through the trans while it's out?

[foggydogg]

Make sure it's not cam seals first.
While it won't make much difference in the end, it could be a transmission input shaft seal too.

[Andrew Vanis]

Make sure it's not cam seals first.
While it won't make much difference in the end, it could be a transmission input shaft seal too.

1) how to check if it is cam seal?
2) "won't make much diff" - it it's cam seals? or transmission input? Or either? And in what way won't it make a difference?

Thanks for the feedback folks.

[scot850]

If I can suggest, first of do the rubber/latex glove test on the oil filler hole. This should give you an idea how bad your PCV system is blocked.
If your PCV system is blocked, it is pointless doing the RMS or even cam seals. If the PCV system is pressurizing the crankcase, then I would replace it, but as suggested this could be done as part of possibly pulling the engine.

Once the PCV system is in good health, If the leak is not too heavy, it might be worth pouring in some Blue Devil or AP-205 and giving the car a good long run. It might be good enough to stop the RMS leaking like it did on a 97 850 my brother has. It was done in 2016 and still running without an RMS leak. I had refreshed the PCV system prior to this, but the car had been sitting for a long time and we were driving it from Calgary to Santa Rosa CA. It started leaking after a hard 1100km one day stint. Through a bottle of Blue Devil seal conditioner in and by the time we got to his house it had stopped leaking.

Neil.

[erikv11]

Neil's post is spot on, start there before getting into the weeds.

First, test the PCV. If it's bad then fix it, then monitor for oil leaks again. ATP AT-205 is the only snake-oil-in-a-can I would consider using, and I'd try it for an RMS leak.

foggydog's cryptic comment is just to point out that the only way to do either one, RMS or input shaft seal. is to remove and/or separate engine and trans.

I wouldn't consider 230k miles very high for your transmission, it could be fine for another 230k.

Getting into the weeds: Yes, that link is very good for removing engine/trans from your car. I would pull them together in order to replace both the RMS and the input shaft seal. And do some other service while it's out: cam seals, timing, PCV.

But first, glove test the PCV.

[Andrew Vanis]

But first, glove test the PCV.

Here it is. Looks like PCV system is ok. Agree/thoughts? Does this change anything in the decision tree for the RMS leak repair?

[Sveedy]

I replaced both seals without removing the trans. Just slipped off the torque converter to access the trans input seal.

[scot850]

Yes your PCV is blocked. Clean the system, and while you have a bit more room, clean as much dirt and old oil off the block and then once reassembled, run and monitor for new leaks.

Neil.