86 W126 420SEL, 2 questions - PeachParts Mercedes-Benz Forum

davestlouis · #1 03-18-2006, 04:59 PM

My 420SEL has always had a power steering leak, but now it's getting bad enough that I'm finally going to address it. It's leaking from the soft line that comes out of the side of the pump and is perhaps 12 inches long. My dealer sells the line in bulk, in 12 inch increments. What size is the line, and is there anything special about the line or clamps? How much pressure is it under?

On a different subject, on the same car...I bought replacement spark plug wires from the dealer...the ones on the car run through black plastic sleeves to keep them bunched together on top of the valve covers...what should I do with the new wires to bunch them together?

Gary Ganaway · #2 03-18-2006, 05:19 PM

don't know about the power steering line but on the plastic sleeves, I slit them and placed the new wires inside. this material is stiff enough that even with the slit it was very hard to open and put the new wires inside.

Also, make sure that when you put the air cleaner back on that this sleeve soe not push against the throttle linkage. I did this and when I took car on test drive it would hardly go. Found the sleeve stopping the linkage.

Hit Man X · #3 03-18-2006, 05:59 PM

The line I recall is about 11-12mm ID. When I purchased online I received about one meter, just shy of four feet. I think it was about $11. The clamps do not cut the line that come on the vehicle, so reuse them. They work well.

While it's apart, I'd toss in a new filter. Maybe reseal the pump too if it's leaking, I spent about $4 per car for a seal kit (including front seal). The one meter was enough to do my SD and the SDL.

No 7 spark plug took so long to do as the EGR valve is in the way.

I haven't installed my new plug wires yet, but I like that idea of a small slit down the covers. I'd probably zip tie them back shut after installing.

davestlouis · #4 03-18-2006, 06:04 PM

I already got the filter. I don't think the pump itself is leaking, so for the moment I plan to change the leaky line and filter and cross my fingers. Just one of a hundred small things the PO didn't bother with. The PO used to have a large income, then he lost that job and had been living hand-to-mouth so he did oil changes and that was about it for the last 2 years or so. He had 107 SL that he sold the same week I bought the 420, and I suspect that car was in the same boat as mine...lots of little stuff needed to be done.

Hit Man X · #5 03-18-2006, 06:15 PM

Okay good deal. Is your PS cap seal okay?

davestlouis · #6 03-18-2006, 06:31 PM

I presume the seal is OK...no leaks from the lid or body of the pump. The hard line out of the pump isn't even greasy, but the soft hose is, and has been dripping/oozing onto the hard line it connects to down on the apron.

Hit Man X · #7 03-18-2006, 08:29 PM

All the seals I picked up for the caps were some new rubber, it appeared the old were made of paper. They were maybe $1 also.

I haven't been under the hood of the 420 for about a week but I recall there are many return lines on its way back. I do not think 12" would be sufficient to replace them.

Consider flushing the system too since you'll have most of the old fluid out. PS fluid is correct now, ATF was a thing of the past.

kodiakj2 · #8 03-26-2006, 12:47 AM

I am sure that this is a bit late, but one foot is plenty to replace that return line. I took a small piece of the original line down to Kragen and matched it to some Goodyear radiator hose. Bought a foot of it ($5.75) and still cut it down about 3 inches from there. Previous posts are right on about the clamps...reuse the originals. This is on my 500 SEC.
As for the plug wires, I bought a few extra spark plug wire holders that fit onto the valve covers from Performance Products for $2.50 each. I put one below the original wire holders towards the plugs and one between the distibutor cap and the original holders on the valve covers on each side. This allows the wires to lay flat under the air cleaner. Makes it look very clean under the hood.
I got really bored one day and hand polished the power steering pump lid with steele wool (00) which made it shine. Got addicted to the polished look so I kept polishing things under the hood...now have a polished air cleaner, cruise control accuator housing, warm up regulator, valve covers and oil filter housing lid. I can now see if there is one drop of out of place fluid or leak on the top end of the engine and the entire engine bay!

vickersw · #9 03-26-2006, 12:59 PM

Just a note of caution... the line discussed is the return line. Not much pressure to wory about, so most any hose would work. However, the fluid Mercedes uses is different from normal cars. You should use hoses recommended for Mercedes use or the hose will deteriorate in time. The hydraulic fluid will cause the hose rubber to break down. The problem will come back with a vengeance!