Power Steering Pump Leak

[Jordan]

Found a leak under the power steering pump.  I've determined that the leak is coming from behind the pully (see first pic).  The drip forms on the inside edge of the pully, no where else.  Looking at the parts diagram, am I correct in assuming it is probably seal #93 that is leaking (see second pic)?  How difficult is this seal to replace?  Can it be done in-situ?  Is it possible to replace this seal without removing the rad?  I'll no doubt have to drain the power steering fluid as a minimum so will likely replace the filters in the bowl at the same time.  Has anyone had to replace just this seal and what am I looking at procedure wise.  Many thanks for the continued assistance.

[rwmastel]

Marcus,

Is that called a seal in the parts catalog?  Wondering if it's a spacer or something else, and the leak needs to be stopped from the inside with part 98 and/or 99.

[MikeSimon]

The power steering pump has a shaft seal. It is a standard design (not dimension) lip seal. Back then, Vickers used single lip seals to seal against pressure from the inside. later they became double lip seals. The pump has a bore that connects the inlet area to the area behind the seal to help draw oil away from there into the inlet area. I think the seal is still available out there. The pump has to be removed, the pulley has to come off.

[mdsalemi]

Found a leak under the power steering pump. 

Marcus, you can purchase the rebuild kits for the PS pump readily in a number of places. It is an easy fix, not in situ but out of the car.

I simply opted recently to exchange my PS pump for a rebuilt. But it's (according to many) not that big a deal to change the seals.

https://www.authenticclassics.com/mercedes-Power-Steering-Pump-Seal-Conical-p/auth-008400.htm
https://www.authenticclassics.com/mercedes-Power-Steering-Pump-Seal-Cylindrical-p/auth-008399.htm

I got my rebuilt pump from Autohaus AZ. https://www.autohausaz.com/pn/1154600980

[Jordan]

Thank you Mikes and Rodd.

Rodd, yes part #93 is listed as a radial seal ring.  I thought because it is an external seal I could possibly do it in-situ but I guess not.

Michael, did you replace the pump yourself?

Is there some way to determine if I have a straight shaft or conical shaft without removing the pump first?  My car is an October '66 build, about 1000 before the last 230SL.

Lastly, can I remove the pump without removing the radiator?  It looks tight but I am hoping so.

[mdsalemi]

Michael, did you replace the pump yourself?

Is there some way to determine if I have a straight shaft or conical shaft…

Well, I just looked at my shaft and said that looks conical to me and sure enough it was…

Since I was replacing the steering gear as well, (I don’t really have the working space or Lift to do any of this) I let my mechanic take care of it. He did a perfect job. And yes, it was easier for him to remove the radiator to get access to the pulley from the pump and removing the pump. When you have a lift, these things are relatively easy. I can barely move in my garage when the car is in it so working on it is out of the question, At least anything serious.

[Pawel66]

I am not a mechanic and I managed to remove the steering pump without removing the radiator. But
- you have to have a way to lift the front the way that ensures comfortable access
- there is a risk of damaging the radiator; place some cardboard on it to protect it
- a lot depends on how cooperative pulley will be
- v belt is easy to remove (cut) tricky to put back

There is a lot of threads about removing the pulley and working with v-belt there, good to study them.

My conclusion is: since I have Quick Jack now and I can lift the car high enough to remove radiator from the bottom - if I were to do it again, I would remove the radiator.

[Jordan]

Thanks Pawel.  I have a 4 post lift so can get under the car pretty easily.  I will try removing the pump without removing the rad since it sounds like it can be done.  If I run into difficulties I can always take out the rad but hopefully it won't be necessary.

[Pawel66]

Keep in mind you have a couple of standard (not metric) bolts there, holding the pump.

There are more threads there, I found this one: https://www.sl113.org/forums/index.php?topic=30276.msg219254#msg219254

[miked_md]

I recently did this repair on my 67 230SL.  The seal kit was $4.95 from Pelican parts.  It included the shaft seal and two O-rings.  I removed the pump and bracket together without removing the radiator.  The pulley came off without too much effort once it was out of the car.  Almost no room between the pulley and the radiator.  If you remove the radiator you can replace the shaft seal without removing the pump, but not the internal O-rings.  Replacing the seal and O-rings was the easiest part of the job.

Classic case of a $5 part and five hours of labor!

[VikDasor]

I recently did this repair on my 67 230SL.  The seal kit was $4.95 from Pelican parts.  It included the shaft seal and two O-rings.  I removed the pump and bracket together without removing the radiator.  The pulley came off without too much effort once it was out of the car.  Almost no room between the pulley and the radiator.  If you remove the radiator you can replace the shaft seal without removing the pump, but not the internal O-rings.  Replacing the seal and O-rings was the easiest part of the job.

Classic case of a $5 part and five hours of labor!

What method did you use to remove the pulley. I have been fighting with it for few days and soaking it up repeatedly with wd40 and plus gas. Also have tried 2 different pullers and few ways that are shown in the forum but no result.
The only thing I have not tried is heat.

The shaft is conical.

[rwmastel]

Other posts make it seem like this should be the easier part of the job.

I've found Liquid Wrench and PB Blaster to work betthan WD40, but I'm sure we could have 100 posts just on that topic!

Tapping around the perimeter of the back of the pully hasn't worked?  If it's out of the car, I assume you could get a puller on it.

If you have a way to heat it, then proceed.
Heat may be your best bet.

[Kevkeller]

I made a puller but I have a lathe and mill. The tool you need pulls it from the center area so you don’t damage the rest of the pulley. Do not pull it from the outer edges.

It did take a lot of torque for it to finally pop off.