KDSS valve rust- WARNING

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Well, I'll add my experience to this thread, with my 2013 4Runner Trail.

I had to do an entire lift kit swap, due to rust breaking UCA's, coils. Had a shop install a Dobinsons setup and Treaty Oak KDSS spacer kit. Well, they never opened the valves to free flow the system.

I get home and see fluid dripping from the accumulator. After a few days spraying the s*** out of the cover plate bolts, I gave up and drilled them out. I expected the worst and that's what I saw.

Aluminum has corroded from dirt and salt sitting on it, despite my spraying that area with water over several years.

I'm waiting on a new part to arrive from Japan ($593). My hope is to spray the lines, remove the fluid from the drain valve, remove the lines, carefully, and install the new part. Then I need to find a dealer to recharge it.

Two questions for some help:

1. How should I drain the system?
2. Anyone know of a dealer in Massachusetts or New England area?

-Art
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View attachment 3681650View attachment 3681651
Might want to post to the 4Runner forum. The LC requires a special tool to pressurize the system to 600psi.

FYI on my LC I slathered marine grease over the KDSS screw heads and they’re still like new 8 years later even with Chicago road salt.
 
Any chance someone is in the NJ area that could help me clean the KDSS valve on my ‘21 LC?

I’m mechanically challenged and will probably mess it up somehow if I try doing it myself. Looks like a decent amount of rust is already forming there.

IMG_2492.jpeg
 
Thanks for the reply!

Again a dumb question, but is this the full sequence?

First remove the cover which is attached by two bolts?

Then I rotate the two valve bolts no more than three turns, wire brush/apply grease. Screw them back in three turns and replace the cover.
I think that’s overkill, but yes it would work fine. If you get small wire brushes you can clean off the hex head valve screws without removing the cover. And there really isn’t a need to open the valves before cleaning and spraying. The oily stuff will get far enough into the threads to save them from being rust-welded in there. In fact, I think on a ‘21, you probably don’t even need to clean off the rust if you use lots of Fluid Film.
 
I think that’s overkill, but yes it would work fine. If you get small wire brushes you can clean off the hex head valve screws without removing the cover. And there really isn’t a need to open the valves before cleaning and spraying. The oily stuff will get far enough into the threads to save them from being rust-welded in there. In fact, I think on a ‘21, you probably don’t even need to clean off the rust if you use lots of Fluid Film.
Awesome. That is very helpful info.

I figured I had to unscrew the valve bolts to properly grease them. But I guess that’s only necessary if the assembly is very badly rusted.

I’ll order that wire brush from Amazon and give it a go. Thanks again.
 
I would definitely remove the cover. See my post further up about my 4Runner. I'd spray the area for years, thinking it got rid of all the dirt and salt; nope, it built up and corroded the aluminum block to the point of having to replace the entire accumulator.

I had to drill out my bolts.

Then get all the dirt off, scrape off the rust, spray the valve bolts with Liquid Wrench, back them out two turns and back in.

Finally, get some good marine grease and cover everything with it. Or, spray it with Fluid Film or PB Blaster - lots of it. A yearly treatment is good.
 
Yes, that's an option for me. When I reinstall the sliders I can bolt on a plate between the slider brackets, just under the accumulator. That way, I can still see the assembly and wash/spray it as needed, without having to worry about removing the rust prone cover bolts. Of course, I can unbolt the plate to gain access for service.

Not exactly going totally coverless but better. Protection and access.

Also, the OEM bolts are steel going into aluminum. WTF were they thinking?!
 
Given the option I would definitely open the valves (NO MORE THAN 3 TURNS) to make sure the applied grease/rust protectant gets pulled into the first few threads. Since you already have a little rust there is a risk that it migrates up the threads into the more sensitive parts of the shutter valves.

I would also wire brush the bolts before loosening to get any scale off them and make sure the socket doesn't slip at all.

When you tighten the bolts again, they do not need to be super tight. Technically the spec is 9ft-lbf, though I doubt you have a torque wrench in that range.
 
Given the option I would definitely open the valves (NO MORE THAN 3 TURNS) to make sure the applied grease/rust protectant gets pulled into the first few threads. Since you already have a little rust there is a risk that it migrates up the threads into the more sensitive parts of the shutter valves.

I would also wire brush the bolts before loosening to get any scale off them and make sure the socket doesn't slip at all.

When you tighten the bolts again, they do not need to be super tight. Technically the spec is 9ft-lbf, though I doubt you have a torque wrench in that range.
 
Very thankful for this thread. Fortunately my 2016 looks pretty good. Recently got my lps3 in and will tackle this.. I'll update what i find.
 
Thanks @linuxgod

I was planning on this lps3 to coat it. I'll definitely keep this taken care of. Appreciate it!
Never used it before. I use marine grease on the valve screws and then spray the underside of my truck with fluid film, which I think is similar to LPS3 each November. My KDSS screws still look and turn like new. That marine grease is still there each fall, whereas the fluid film has pretty much worn off by spring. I’m in Chicago and get salty roads so it probably doesn’t matter what you use in Texas but I still think it’s worth coating down there because even salt air is probably bad for them, and you can’t see the corrosion happening until it’s too late being that it’s under the truck. I happen to like marine grease because it seems to stick around for years, so if you aren’t planning to regularly deal with coating your truck down there you can probably coat once every 5 years
 
I happen to like marine grease because it seems to stick around for years, so if you aren’t planning to regularly deal with coating your truck down there you can probably coat once every 5 years

Just as a data point I am in Texas and put LPS3 on my KDSS valve when I got my 200 going on seven years ago. My winter-road use is limited to a couple big ski trips per year up to colorado, if not all the way to montana/wyoming/idaho/wherever.

Texas is so easy on these things (and/or LPS3 so good) that I haven't had to reapply it so far.

Personally I'd lean your direction if I lived in a place with regular salting of roads, but if that level isn't needed the LPS3 is much cleaner and very effective.
 
Just as a data point I am in Texas and put LPS3 on my KDSS valve when I got my 200 going on seven years ago. My winter-road use is limited to a couple big ski trips per year up to colorado, if not all the way to montana/wyoming/idaho/wherever.

Texas is so easy on these things (and/or LPS3 so good) that I haven't had to reapply it so far.

Personally I'd lean your direction if I lived in a place with regular salting of roads, but if that level isn't needed the LPS3 is much cleaner and very effective.
Cool. In my experience fluid film only lasts one winter before rain eventually washes most of it off. So I assumed LPS3 would be similar.
 
Cool. In my experience fluid film only lasts one winter before rain eventually washes most of it off. So I assumed LPS3 would be similar.
I think the shield over the KDSS valve really helps knock down the direct road spray, but that’s just a hunch.
 

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