Topic: Drilling out ps pump restrictor

[superyota]

I recently burned up my ps pump. I'm running locked toyota axles, 40s, and hydro assist. I've also been running power steering fluid rather than ATF. No leaks or issues for the past 3 years til now. I'm planning on swapping my burned up pump for another stock pump for now. Just wondering how many people here have first hand experience in drilling out the restrictor and if they had problems with burning up the pumps or noisy pumps. Dies it make a noticeable difference when its drilled? Also, what are the people who are running ram assist using for fluid, ATF or ps fluid? Toyota says run ATF and the RA says run ps fluid. Will ATF eat up the ram seals?

Any input would be appreciated. Please also post up your rig specs(tire size, locked, fluid used, how long,etc).

[85runner_]

I have drilled out stock plate some. Not huge but bigger than stock. Can I notice it? Idk. I did it the same time I added the assist so hard to tell.

I use gm power steering full syn fluid. Little spendy but after reading up it was the best at the time. I don't know what's best now but it works. I can wheel hard all day. Pop the cap off dip my finger in and it's Luke warm at best.

You need to have a larger resi and a nice cooler if you don't already.

Toy buggie locked f and rear 40ds

The stock pump barley puts out enough psi and gpm. It works but I will be upgrading to a high output one to utilize the full potential of the steering system.

[OOPS]

I have full hydro and my buddy has HA and this is all we will run. Runs cooler and no whine!!!! Some comp drivers turned us on to it.

[superyota [OP]]

Hey oops, what pump are guys running?

[OOPS]

Hey oops, what pump are guys running?

PSC, cannot remember which one though.

[superyota [OP]]

So I took the high pressure line and fitting off. The pressure release valve was stuck way inside the pump. I was able to shimmy it back and forth til it popped out. While I had it out I drilled out the restrictor and stretched the spring out just a bit that sits in the pump just behind the restrictor. Put it all back together and it works better than it did before. Been reading up and seems like some guys have problems with burning up the pump quick after doing this. It doesn't squeal at all so I'm hoping it will last a while. I got plenty of wheeling still to do this season. Moved to Lincoln and I'm close to some prime wheeling so I'll post up and let you guys know how it works out.

[superyota [OP]]

Here is a good right up I found. Not sure if I bumped the pressure up or not. I stretched the piston spring. Figured this would make it less likely to get stuck. Anyone have experience with stretching the piston spring?

http://westtexasoffroad.homestead.com/powersteering.html

[jrock]

I really don't thing drilling the restrictor will change the pressure but it will change the GPM. You need to drill the restrictor but how much is up to you. I did one size drill bit larger, ~1/16", and my ram and box and very close in speed. But I still get a lot of lag when going stop to stop. For me its not the pressure but more o a flow issue.

[superyota [OP]]

I have 0 lag right now vs before it almost felt like it would bind up a bit when cranking back and forth. I'm more wondering about the piston spring that I stretched out. I read up and it says it holds pressure longer before it goes to bypass. Correct me if I'm wrong. Just wondering if anyone else has stretched the same spring and what the results were long term.

[jrock]

So what does that spring do?

[superyota [OP]]

From What the west Texas site says, it makes it hold pressure longer before it goes to bypass.

[jrock]

So the pump has an internal bypass? And so does the box?

Then there may be some credibility to stiffening the spring. Maybe someone should put a pressure gauge on a pump and find out

[superyota [OP]]

I don't think the box has a bypass. Just the pump does. According to the link I posted you need to shim the bypass by taking it apart. I didn't do that. I just stretched the spring the sits inside the pump that the bypass valve/piston sits against.

I also noticed in my neighbors ftoy, when we did the same to his, rather than one hole in the restrictor there were 2 small holes. We drilled the center of the two out to make it one big hole. Also the piston spring in his was half the length of mine. Not sure why they are different. Both 22re, just mine is older.