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Discussion Starter #1
Anyone got one.....? a way to repair or create a new version of that nasty little formed gasket in the main body of the EHCS?
Had to try refilling mine (again) as it wouldn't go up when the temps got over about 22 C... hydraulic fluid didn't seem thick enough to work, so I used 20W-50 motor oil, and it seemed to work fine... until I noticed it started leaking from around the skid plate. Been using the EHCS all week and just putting a rag under it, its been working fine but I knew there was a leak somewhere.
Finally got to remove it again today, and there was the tiniest little bit of gasket poking out of the edge of the unit. Must have over-filled it.... sigh...
Pulled it all apart and the gasket is complete but has a slightly damaged edge that I guess isn't sealing properly.
I tried putting a little silicone sealant under the gasket where it had popped out to help seal it, but during the initial test after refill I noticed some oil leaking again.

Any ideas what to use to get a proper seal? Is there a gasket goo or liquid rubber sealant anyone can recommend for this purpose?








my wonderful bike lift....

 

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20/50 oil blew your seal out. I haven't had one of these apart so I don't know what their using for a relief.

It blew the weakest point. In hydraulics a few things can happen with over pressure, it stalls the motor, blows a seal, splits the housing.

You need a new seal, silicone will never seal it. Even if you were able to seal that area, you will have another failure point using motor oil. Dead head a fixed displacement pump and it will fracture.

Find the original cause of no operation (I would guess you're bleeding flow past a sealing surface, the motor oils flow was restricted through the leak to build enough pressure to operate the stand until another seal failed), repair it, use hydraulic oil.
 

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Most sealings of the LT are silicone sealings, means fluid sealings from "Threebond". Since I am working for that company as a Sales Eng., I highly recommend you a product what is called TB 1227C. Great working product!!

Throw away the old one and replace it with the product as mentioned. You can get it in catridges.
 

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Wrencher Extraordinaire
2005 K1200LT
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Here is what I did. Cleaned it up and smeared a bit of grey silicon seal on the area and let it cure a few days before I refilled it. Has lasted four years so far.

That happens when you put too much oil in. Only put 125 -150 ml. I use hydraulic jack oil commonly available at all out auto parts store ere on this end of the world.
 

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Discussion Starter #5
Thanks all.
John, it looks like yours blew in exactly same spot as mine did.
I put it back together with a little Selleys roof & window silicone sealant while waiting for seasoned comments ;), but only put the sealant into the groove under the gasket along that long edge. When I "bench tested" it (minutes later) it seemed to still leak a little fluid but hadn't popped the gasket again, so I put some more silicone along the outside edge and let that cure overnight.
I've used the stand twice now since then, and it doesn't appear to be leaking (yet)... will keep fingers crossed and see if it stays dry outside (and keeps working in higher temps).
I've still got the 20W/50 in it, as the jack oil just wouldn't work when it got hot.
At worst I'll have to rip it off again in a couple of weekends time and try something else.

Rudy, thanks for the product info, I'll see if its available in Oz.
 

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Wrencher Extraordinaire
2005 K1200LT
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New2rt said:
20/50 oil blew your seal out. I haven't had one of these apart so I don't know what their using for a relief.

It blew the weakest point. In hydraulics a few things can happen with over pressure, it stalls the motor, blows a seal, splits the housing.

You need a new seal, silicone will never seal it. Even if you were able to seal that area, you will have another failure point using motor oil. Dead head a fixed displacement pump and it will fracture.

Find the original cause of no operation (I would guess you're bleeding flow past a sealing surface, the motor oils flow was restricted through the leak to build enough pressure to operate the stand until another seal failed), repair it, use hydraulic oil.
This is not the pressure side of the system. This seal only blows out if you over fill the unit as the "relief" dumps into this area. If it is full then it blows the seal (best case) or cracks the housing (worst case). I had over filled mine before we were able to get the original designer to cough up the fill parameters of 125-150 ml. Mine has been sealed like this for five years. I concur with using hydraulic oil vs motor oil.
 

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jzeiler said:
This is not the pressure side of the system. This seal only blows out if you over fill the unit as the "relief" dumps into this area. If it is full then it blows the seal (best case) or cracks the housing (worst case). I had over filled mine before we were able to get the original designer to cough up the fill parameters of 125-150 ml. Mine has been sealed like this for five years. I concur with using hydraulic oil vs motor oil.
It's not but it can become pressurized. Especially if you stall the cylinder, overfilled, and thermal expansion (fluid over relief gets hot) The original issue was loss of operation.Based on that I would say he's loosing flow due to a worn or damaged seal. The 20/50 is heavy enough to restrict the flow past this leak and build enough pressure to operate the stand.

You need to find the original reason why the stand doesn't operate. 20/50 is a band aid that will lead to future problems.
 

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Discussion Starter #9
Well, so far its fingers crossed and 3 days in no further sign of leaks, and with about 130ml of 20W-50 in it, its still working OK.
I definitely overfilled it when rebuilt 2 weekends ago, causing the blow-out. My bad.
Have rebuilt it several times now, without ever finding out why the Marzocchi pump couldn't be re-tightened as expected after the first pull-apart without adding an additional paper gasket ( it locked the gears up without it). All the seals appeared to be fine, my initial problem was the motor was stuffed.
Waiting for the temps to get back into the mid 20's to see if the heavier oil does its job, where the hydraulic fluid couldn't.....

And despite the issues, I love having the EHCS, and so does my back that's already had 1 operation years ago... :)
 
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