"Best" 5mm hex (allen) socket? (1 Viewer)

[bloc]

@bloc since you may be the only person to ever have one of these apart - isn't the primary sealing surface the interior conical end of the shutter valve screw against the taper of the valve body, not the rubber o-ring?

My completely unsubstantiated and uneducated theory is that there is so much thermal mass in that giant block of steel that the o-ring doesn't get that hot during a brief welding operation, even though a lot of heat is applied in a concentrated area.

There are two sealing functions on each of the screws. The conical end seals one circuit (top or bottom of the cylinders) from the central accumulator circuit. The o-ring then seals this accumulator circuit from atmosphere. Under normal operation the accumulator circuit is the same pressure as the cylinders.. over 600psi. The cylinder circuits can see more or less depending on what’s going on but the accumulator circuit should stay around there.. exactly what the accumulators are designed to do.

So yes the orings have a very important function. I think you are correct about the valve block likely taking a lot of thermal energy before the area of the orings gets to a dangerous level though.

 

[FrazzledHunter]

I would imagine the problem is the bolts being upside down.. it doesn't have a chance to seep in there

I've unstuck brake bleeders, saving me the cost of a new caliper, by attaching a cotton ball to the calipers with wire ties, rubber bands etc... (whatever is lying around) so that the cotton ball touches the threads. Then I saturate the cotton ball with Liquid Wrench and let it sit overnight or even drive around with it like that for a few days.

I know that the bolts are upside down but tying a cotton ball saturated with penetrating oil might keep them wet so the oil penetrates. Might this approach work?

 

[silverhorse]

Anything is worth a shot ..I even tried heat but I didn't want to heat it for long

 

[CharlieS]

Success!! I got the other screw to break loose. Even the snap on socket was twisting (twisting, not snapping, which was nice), so I decided to try more heat. I used a mapp gas torch and gently heated it. I hit it with another dose of kroil while it was still warm, and gave it another shot. It ever so slowly popped loose, in three tiny lurches, then it was free. I am so psyched. This was after a week of twice daily kroil, and five broken bits. What a way to end the week. Woo hoo.

 

[teambell]

Congrats!

 

[bloc]

Very nice! Now go the three full turns out and put your choice of grease or anti-seize on all the exposed threads, then turn it in and back out a couple times to spread it around. Final torque 10ft-lb/120in-lb

But no more than three! (I know you know this but for anyone new, it is critical you don’t go past three turns out!)

 

[Markuson]

Very nice! Now go the three full turns out and put your choice of grease or anti-seize on all the exposed threads, then turn it in and back out a couple times to spread it around. Final torque 10ft-lb/120in-lb

But no more than three! (I know you know this but for anyone new, it is critical you don’t go past three turns out!)

I don’t remember ever hearing a torque value for these valves. Thank you.

 

[Nola622]

Success!! I got the other screw to break loose. Even the snap on socket was twisting (twisting, not snapping, which was nice), so I decided to try more heat. I used a mapp gas torch and gently heated it. I hit it with another dose of kroil while it was still warm, and gave it another shot. It ever so slowly popped loose, in three tiny lurches, then it was free. I am so psyched. This was after a week of twice daily kroil, and five broken bits. What a way to end the week. Woo hoo.

Congratulations! My snap-on 5mm twists like that as well. So the main take away for folks stuck on this in the future is that heat is the key. Once we had a Mig welder on ours it seemed like it had never been stuck.

 

[CharlieS]

I think the heat was likely what made the last bit of difference, but I also suspect that heat alone wouldn't have solved this.

I don't have any way of knowing but I suspect that I was almost there with the combined impact of several things - repeated application of high quality penetrating fluid (mostly kroil) over an extended period, cleaning well with a wire brush, and using a pick to clean around the perimeter - and the heating pushed me over the goal line.

This thread was very helpful to me and I feel like I now know about more good options for higher quality bits. I think it is definitely worth shelling out a bit extra to buy a high quality tool for this job.

And if you do apply heat, please be careful. I was pretty nervous since that is a high pressure system. No telling what damage and injuries could occur if it let go. And a vehicle fire is a potential risk. It was impossible to keep that much heat confined to just the small area that needs it with a mapp torch, so I went slow, monitored the heat as I went, and cooled the entire area afterward.

Thanks for the help everyone.

The one on the right side of this photo is the one that stuck. This is on a'16 that lived its life in the NYC area, otherwise minimal corrosion (frame welds only). In four years the kdss valve assembly is already pretty badly rusted.

 

[bloc]

I think the heat was likely what made the last bit of difference, but I also suspect that heat alone wouldn't have solved this.

I don't have any way of knowing but I suspect that I was almost there with the combined impact of several things - repeated application of high quality penetration fluid over an extended period, cleaning well with a wire brush, and using a pick to clean around the perimeter - and the heating pushed me over the goal line.

This thread was very helpful to me and I feel like I now know about more good options for higher quality bits. I think it is definitely worth shelling out a bit extra to buy a high quality tool for this job.

And if you do apply heat, please be careful. I was pretty nervous since that is a high pressure system. No telling what damage and injuries could occur if it let go. And a vehicle fire is a rear risk. It was impossible to keep that much heat confined to just the small area that needs it with a mapp torch, so I went slow, monitored the heat as I went, and cooled the entire area afterward.

Thanks for the help everyone.

With regard to the high pressure system - I don’t think you were in any personal danger. Even if the oring let go the oil would have to come out through the threads around the screw and that would slow it down dramatically.
But yes to fire risk etc.
Again, really glad you got this sorted. Proving that perseverance is key on these stuck valves.

 

[drfous]

So this thread got me looking at my valve.

Bought my 2020 in Sept. The original owner had the OME suspension done along with a KDSS relocation at a shop in NC.

When I checked the valve, it has regular bolt heads and not hex screws.

Did Toyota make a change? Or did the shop change it out?

Thx

 

[Yossarian]

Posted before, but why not again.

Factory info, 2 to 3.5 turns out MAX.

Factory torque specs.

Info directly from the source, Toyota TIS.

TIS (toyota.com)

 

[CharlieS]

So this thread got me looking at my valve.

Bought my 2020 in Sept. The original owner had the OME suspension done along with a KDSS relocation at a shop in NC.

When I checked the valve, it has regular bolt heads and not hex screws.

Did Toyota make a change? Or did the shop change it out?

Thx

Yes. Changed over in 2018, if I understand correctly.

 

[FrazzledHunter]

Yes. Changed over in 2018, if I understand correctly.

My '18 has bolt heads.

 

[dougparis]

Great!! But....now what? That was a fun ongoing trilogy!
Who is up next?

 

[dcs111]

Success!! I got the other screw to break loose. Even the snap on socket was twisting (twisting, not snapping, which was nice), so I decided to try more heat. I used a mapp gas torch and gently heated it. I hit it with another dose of kroil while it was still warm, and gave it another shot. It ever so slowly popped loose, in three tiny lurches, then it was free. I am so psyched. This was after a week of twice daily kroil, and five broken bits. What a way to end the week. Woo hoo.

I put the truck in the shop for suspension surgery this week and received a bit of bad news from the doc. looks like I will be following this group's efforts to remove rust and free up the infamous KDSS valves. wish me luck

 

[dcs111]

I usually use inductive heat on stuck bolts. The leads can be twisted to whatever you need to apply it to.

@rlynch356 do you have a make/ model for this inductive heat tool? TIA!

 

[rlynch356]

Amazon product ASIN B0851C6Q22

they all see the same, just different prices