KDSS - UNfrozen! :) How I did it... (2 Viewers)

[TonyP]

Another approach:

If you have the ability to use air tools, these types of things work wonders. Just make sure to use quality bits.

Eastwood Screw Buster Remover

Loosens Rusted, Corroded, Undercoated, Painted and Over Tightened Screws.

www.eastwood.com

 

[bloc]

Another approach:

If you have the ability to use air tools, these types of things work wonders. Just make sure to use quality bits.

Eastwood Screw Buster Remover

Loosens Rusted, Corroded, Undercoated, Painted and Over Tightened Screws.

www.eastwood.com

That is a damn good idea..

 

[dcs111]

That is a damn good idea..

I wish I would have seen this before trying the more practiced methods in posts here! PSA below

For anyone who may deal with the infamous rusted KDSS shudder valves, I will provide some detail as to what happened:

- 2013 LC - lived part of its' life in NY and to my knowledge there would have been no reason to open the valves at any point in the vehicle's life, until I recently decided to upgrade the suspension... vehicle has always been maintained by Toyota and as prescribed. There is some rust on the underside, but save for the KDSS I would say it is really cosmetic. Nonetheless, these valve screws and surrounding body were really rusty...

1. I wire brushed the housing, valve screws, etc to the point where I did not feel the wire wheel was providing any more help in attempt to reduce rust.
2. Next found a set of mechanic's picks and removed scale/ rust from between screw head and housing.
3. Next soaked the screws/ body with PB Blaster for several days
4. I procured some Kroil, 5mm hex, and a map gas torch in prep for next steps :| Once the kit arrived, I decided to attempt to break one of the screws free... oh man
5. The socketed section of the screws where the 5mm hex would go were malformed by rust and scale and so I had to tap the bit into the screw with a small hammer to achieve a full seating of the hex socket. I did not want to apply too much torque and so I decided to double the torque rating for install (10ft/lbs) to (20ft/lbs) for my attempt at breaking the valves free; unfortunately my torque wrench min was 25 ft/lbs and so that is what I used. first few attempts to loosen/ tighten with oil only and it was pretty clear these things are rusted in hardcore... I probably tried this for 5 pops of the TQ wrench in both loosening and tightening direction - no joy... Next to try some heat...
6. I decided I would try MAP gas on the housing surrounding the screw (lots of research on best means to apply heat and the general consensus is to apply to the nut, which in this case is the housing). I wanted to be "measured" in approach and so I had ordered an infrared temp gun, but was too impatient to wait. next option was to go with timed application of heat, starting with 10 seconds. At 10 seconds, the outcome was essentially the same - no joy. I took the same approach several times at 15 seconds and then to 20 seconds of heat. I also tried application of oil while the assembly was allegedly hot with no luck. I am guessing I tried 50 or more times to torque the hex socket at around 25-30 ft/lbs when it gave. And the remainder of the 5mm bit is now FIRMLY embedded in one of the shutter valves.
7. In doing some research on maximum oil temperatures in hydraulic systems, it seems that 160 degrees is about as hot as you want to go on a pressurized system. this is from a tractor forum and so someone may have more pertinent info, but this is all I could find. Anyway, I am doubtful i got close to that, but in hindsight should have waited for the infrared thermometer to try for a more precise approach to raising metal temperature (and less clicks on the TQ wrench).
8. Also, I am sure I was raising the temp of the socket as I did not remove it during each torch application. As an aside, I did not apply heat directly to the tool itself and so not sure of the impact on the tool.

If anyone has any suggestions on removing the tool metal from the valve screw, I would appreciate it. I have a meeting with a welder tomorrow to discuss welding on a bolt to complete the effort...

 

[CharlieS]

I had a very similar experience (documented elsewhere here). Week or more of penetrating fluid, scraping, wire brushes. BFH whacks to the bit, butane torches, hand impact driver... Map gas and snap on sockets ended up working for this one. More heat than I was happy applying, in fact.

The last 200, I had to use the welded nut technique. This was a situation where I had the end of an Allen bit broken off, was firmly stuck and I couldn’t get it out.

I think the heating and cooling of both of those approaches does more to help break the corrosive bonds.

I am not sure, but I thought I heard that it was a bad idea to use a torque wrench in removal. Messes up the calibration or something?

 

[dcs111]

I had a very similar experience (documented elsewhere here). Week or more of penetrating fluid, scraping, wire brushes. BFH whacks to the bit, butane torches, hand impact driver... Map gas and snap on sockets ended up working for this one. More heat than I was happy applying, in fact.

The last 200, I had to use the welded nut technique. This was a situation where I had the end of an Allen bit broken off, was firmly stuck and I couldn’t get it out.

I think the heating and cooling of both of those approaches does more to help break the corrosive bonds.

I am not sure, but I thought I heard that it was a bad idea to use a torque wrench in removal. Messes up the calibration or something?

re: torque wrench that sounds about right, but i was happy to sacrifice a TQ wrench vs screw this up... well probably accomplished both

 

[dcs111]

re: torque wrench that sounds about right, but i was happy to sacrifice a TQ wrench vs screw this up... well probably accomplished both

I am happy to report that the trip to the welder was a success! It took several attempts (I think 5) for us to figure out the correct combination of parts, but both valves now open! She looks a bit Frankenstein, but what you see in pic is a washer with diameter larger than existing hex bolt tacked to the hex and then the head of a bolt welded to the washer. We found that the extra metal was needed to avoid shearing when breaking the rust bonds...

 

[CharlieS]

Was there any explanation of why a bolt was used, rather than a nut? Using a nut allows you to weld a rosette inside.

 

[bloc]

Was there any explanation of why a bolt was used, rather than a nut? Using a nut allows you to weld a rosette inside.

I'm guessing that's what the washer was for, before welding the bolt to it.

 

[dcs111]

I'm guessing that's what the washer was for, before welding the bolt to it.

Not an expert an welding, but can confirm the washer did the trick; every other option we tried prior sheared somewhere.

 

[DuckNinja93]

As several folks here have discovered, the KDSS cast housings are prone to rust (this is possibly the understatement of the year). The valves - which need to be opened in order to level a vehicle while installing a suspension upgrade - are conveniently located in the place most vulnerable to road salt and corrosion. These valves are often rusted and considered "frozen" even on newer models that aren't in the "rust-belt" of the country.
Some Mud members have had them replaced under warranty and others are considering selling their vehicles because they don't want to replace this expensive item ($2K sounds familiar) just to get a lift.

My KDSS main housing looks like it was dragged out of the bottom of the ocean. It's the only item on my rig that looks this bad (thank goodness). I should have removed the cover before taking this photo, but you can see that it is in awful condition. The rust was covering the 5mm hex bolt heads to the point where I didn't even see them at first!View attachment 1210821

(BTW - what is that connector for?)

After breaking off the heads of a few bleeder valves on brakes, I resigned myself to the fact that this would be a longer process - waiting days and even weeks before I really took a stab at loosening them.

I hit the screws with PB blaster once a day for a few days - thinking I would let that stuff really penetrate. It seemed clear that nothing was happening so I researched better penetrants. That's when I discovered KROIL.

I sprayed Aero-Kroil on there and could actually see it loosening rust almost right away. After a few sprays, I used a stiff wire brush and a dental pick (neither are shown in the picture) to get in the grooves around the screw-heads. With a few more sprays of KROIL I could now see the outline of the heads and some of the rust was coming off. I waited a day and tried to loosen them with my 5mm socket - but they wouldn't budge and I could feel one starting to strip.
View attachment 1210838

A little discouraged, I sprayed more KROIL and then inserted the 5mm allen wrench in the screw heads and tapped gently with a hammer. I tapped a bit on the edge of the screw heads as well (all around).

I waited a few more days....

Today I sprayed a little Kroil and used another wire brush to remove more rust. The screw heads started looking cleaner and really well defined. I tapped the screw heads again with the wrench/hammer inside the screw head and around the outside of the screw head. Now when I sprayed I could actually see the Kroil making little bubbles around the head of the screw. (or that was my imagination).
View attachment 1210837

I waited another 1/2 hour and then took my 5mm socket and gingerly applied pressure....I felt a little "crack" as it released and I almost pee'd in my pants with excitement. The second went just as easy!
View attachment 1210836

Now I loosened them 3 turns, cleaned the threads a bit, applied grease and tightened and loosened them again. YAHOO! - now I can get a lift!

 

[DuckNinja93]

Thakn

As several folks here have discovered, the KDSS cast housings are prone to rust (this is possibly the understatement of the year). The valves - which need to be opened in order to level a vehicle while installing a suspension upgrade - are conveniently located in the place most vulnerable to road salt and corrosion. These valves are often rusted and considered "frozen" even on newer models that aren't in the "rust-belt" of the country.
Some Mud members have had them replaced under warranty and others are considering selling their vehicles because they don't want to replace this expensive item ($2K sounds familiar) just to get a lift.

My KDSS main housing looks like it was dragged out of the bottom of the ocean. It's the only item on my rig that looks this bad (thank goodness). I should have removed the cover before taking this photo, but you can see that it is in awful condition. The rust was covering the 5mm hex bolt heads to the point where I didn't even see them at first!View attachment 1210821

(BTW - what is that connector for?)

After breaking off the heads of a few bleeder valves on brakes, I resigned myself to the fact that this would be a longer process - waiting days and even weeks before I really took a stab at loosening them.

I hit the screws with PB blaster once a day for a few days - thinking I would let that stuff really penetrate. It seemed clear that nothing was happening so I researched better penetrants. That's when I discovered KROIL.

I sprayed Aero-Kroil on there and could actually see it loosening rust almost right away. After a few sprays, I used a stiff wire brush and a dental pick (neither are shown in the picture) to get in the grooves around the screw-heads. With a few more sprays of KROIL I could now see the outline of the heads and some of the rust was coming off. I waited a day and tried to loosen them with my 5mm socket - but they wouldn't budge and I could feel one starting to strip.
View attachment 1210838

A little discouraged, I sprayed more KROIL and then inserted the 5mm allen wrench in the screw heads and tapped gently with a hammer. I tapped a bit on the edge of the screw heads as well (all around).

I waited a few more days....

Today I sprayed a little Kroil and used another wire brush to remove more rust. The screw heads started looking cleaner and really well defined. I tapped the screw heads again with the wrench/hammer inside the screw head and around the outside of the screw head. Now when I sprayed I could actually see the Kroil making little bubbles around the head of the screw. (or that was my imagination).
View attachment 1210837

I waited another 1/2 hour and then took my 5mm socket and gingerly applied pressure....I felt a little "crack" as it released and I almost pee'd in my pants with excitement. The second went just as easy!
View attachment 1210836

Now I loosened them 3 turns, cleaned the threads a bit, applied grease and tightened and loosened them again. YAHOO! - now I can get a lift!

Thanks for this POST! I ran into this problem when starting my 2" lift this weekend. Found your post and that gave me faith to keep at it. I used PB Blaster and it took about three hours of wirebrush, scrapping, and constant socking - when it finally broke loose, woot! Again, your post saved my bacon. I'm slimming up my KDSS w/ waterproof grease and will check them monthly. Horrible location for this system.

 

[Mdog97]

Took off the protective / skid plate at last weeks first oil change, found the valve body fully encrusted in rust, but everything else underneath relatively clean. I had forgotten to bring my Kroil to my friend's shop, so I used whatever penetrating oil they had, sprayed some on the bolt heads, and left the skid plate off in the trunk.

Today I crawled under the truck and tried the bolts. The outboard one broke free with some force, but I really had to go full monty on the inboard one to get it to break free. I upgraded from the 1/4" drive to 3/8" drive socket set with a longer ratchet to get more leverage, which also upgraded from 12 point to 6 point sockets, which I think helped avoid potentially rounding off the bolt.

I wasn't on completely level ground, and I didn't want to induce a lean where there was none before, so I only loosened about 1/2 turn each, sprayed some LPS3, and re-tightened, and then reinstalled the skid plate.

I used 10 ft-lbs on my small, seldom used 3/8" drive Snap On mechanical torque wrench - is that the correct torque figure for these bolts?