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See that bolt I've circled at the top of the ABC gubbins at the front?
It's dripping and making a mess (this is after I've cleaned up a bit!) of everything in the area, not to mention my driveway...
I'm not sure what that bit is called, it's above the valve body itself... and it looks like it's going to be a PITA to get at.
Has anyone got any ideas of how to reseal that without having to take the whole lot off the car? I'm guessing it's going to need a bit more than just nipping up tight.
I'm thinking unwind it a bit if I can get a spanner to it, then either some sort of silicone sealant or maybe PTFE tape around the thread before doing it back up again?
Silicone sealant is not going to work under 2000 psi. PTFE tape is not recommended in automotive work, because little pieces come off and then clog things further down.
I would expect this bolt to have either a copper washer or an o-ring.
Personally, I would remove just this bolt, check for an o-ring, and if none, re-install with a copper washer.
Silicone sealant is not going to work under 2000 psi. PTFE tape is not recommended in automotive work, because little pieces come off and then clog things further down.
I would expect this bolt to have either a copper washer or an o-ring.
Personally, I would remove just this bolt, check for an o-ring, and if none, re-install with a copper washer.
I didn't think PTFE was a goer really!
The bit in bold is going to be the trick though. It's pretty inaccessible on the car, and I don't know how long/deep it is - if it's just a shallow bolt, it might be possible to get it out and in again (but would there be room for a washer??)
If I have to take the entire assembly out, then I suspect I'd likely end up with more leaks putting it back together....
While I have some spare ABC parts, I don't have that part to experiment with. Maybe someone here knows how long the bolt is or has a spare part to play with.
Now that we have the part number, I see them available used on Ebay for anywhere from $15 to $55. Looking at the pics, I think I see a metal sealing washer under the bolt.
To remove it, you would first remove the fluid lines; you need a "crawfoot flare nut wrench", likely 17mm, maybe 19mm. Like this:
It appears there is one more mounting bolt then holding it to the chassis.
However, if you can access just the mounting bolt, you might be able to move it enough to get the side bolt out and replace the sealing washer.
I'd found the part number in the meantime as well, and zoomed in enough to confirm the sealing washer.
The 2 front pipes are flexis and could easily be undone and moved out of the way; the trouble is going to be the rigid hose that bolts in the far end to my leaky bolt - it's a short pipe that goes down to the valve block.
I'm not sure I could get a wrench on it at all, it was hard enough to see it even! That's the thing that would probably stop me getting just this block out. I'm not sure how possible it would be to bend this out to an angle a bit, then push it back? Picture below.
I have messaged a private seller on ebay with this part to ask if they would undo that bolt and see how deep it is... probably won't hear back, but never hurts to ask
I'm a bit fed up, as I replaced the accumulators a few weeks ago and thought I had the system sorted, several hundred miles of red ABC error free driving... when I noticed the drip, I first assumed I didn't get the front accumulator tightened up enough - no such luck!
If I can't get any further specific information, I guess I'll start trying it step-wise - start with the bolt, then see if I can free just the small block, then go for the whole assembly if I have to.
Anyone know wheer to get caps and plugs for the lines and their holes, to keep them clean and not lose too much of the new CF I flushed it with?
That's the return manifold and I think that 'bolt' is a regulating valve to maintain some backpressure. It is very low pressure compared to the rest of the system.
Turns out a friend of mine used to repair hydraulic systems in a Ford factory, he's giving me a tube or two of specialist sealants (Loctite, can't remember the numbers) that might well cure the drip without removing everything. Can't see I've got much to lose giving them a go
Just sold my '11 Porsche TurboS cab for an '03 SL55!
It's really not that tough to remove the whole sub-assembly. It takes about 3-4 hours to R&R the unit. You'll find that all of the hoses have quick disconnects that ideally require a special fork like tool to pull them, but I've done it several times using needle nose pliers.........but I've regretted not having that tool.
HOWEVER, as I recall, if you just undo the bolts/nuts that mount the sub-assembly, the whole thing can be moved around such that I believe you can pull that cartridge valve (or maybe it's just a plug) and change out the O-ring. Forget the Loctite......even if you wanted to use that, you'd still need to unscrew the plug/valve as for that to work, it has to be in the threads to work, you can't just put it on the outside around the hex and expect results, I've used it also in other situations and, have extensive aircraft hydraulics experience.
2016 S550 sport, 2018 GLC300, M3, Zo7, 2021 Sierra Denali
A sealing washer is a crush washer. Soft..aluminum or copper. I would not be using any sealants in the abc system. The FIRST thing to try is get a little turn tightening it and see if you get lucky sealing it. Its the keep it simple stupid method. Hopefully you get luck...good luck.
Couldn't tighten that bolt, the spanner just slipped off and took a small gouge out of the top corner of the hex.
But it did loosen off ok and came out a bit before hitting the bracket, at least once I had the 2 pipes on the front out of the way:
As you can see, the washer is loose on the bolt and my friend thinks it may have been a dowty washer with a rubber centre originally.
Anyway, I could see a thread or two, so decided I'd try the Loctite. Dripped some all around, made sure it was both sides of the washer, and tightened back up.
The bolt tightened by an extra flat/60' this time (the slip-gouge proved useful as a marker)... and didn't start leaking.
I waited a couple of hours (spec says 45 mins for this Loctite) and ran the car for 10 minutes or so, raising and lowering... no leak
I'm leaving it overnight and checking again before putting the wheelarch liner and undertray back in, but fingers crossed this has fixed it.
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ABC leak at the front
