Obama's Flow Is Adequately Hydrated

[IZwack]

So what is the exact purpose of this pump? Is it only keeping the reservoir filled or does it go inline with the main pump? It sounds like it's only going to feed the reservoir from the previous description.

Sorry for the confusion .. the idea is to put the electric pump inline so the flow circuit goes Reservoir --> Electric Pump --> Hydraulic Pump. The purpose of the electric pump is to feed the hydraulic pump because right now, the hydraulic pump starves and I can hear this weird noise as pockets of air make their way into the hydraulic pump.

 

[BrooklynBay]

Maybe you could use a gravity feed with a check valve to prevent backflow?

 

[IZwack]

Maybe you could use a gravity feed with a check valve to prevent backflow?

Backflow isnt the problem -- its the hydraulic pump starving.

BTW BrooklynBay -- you mentioned that you own that pump I linked to. How long have you had it and about how many minutes (or hours) have you had it turned on? I ask because reliability is very important. If this pump fails, I will have no steering. Typically, I only have my vehicle running for maybe 10-20 minutes and its back off for a little bit waiting for the rigs ahead to make it through the next course.

 

[BrooklynBay]

I bought it for a project I was working on but haven't used it yet. They only recommend using it for water.

 

[IZwack]

Well I guess I should update this thing..

I decided not to go with the electric pump idea because its one more thing that could fail in the system. Sooo.. I built a large(r) reservoir that holds about 1.5 quarts. I'll get a pic of this sometime later.

But one setback is that now the pressure is back down. I have no idea what the deal is but now the pressure only holds a steady ~1250-1300 PSI. My guess is that the washer I placed inside the flow piston "coned" (as the flow piston's bottom isnt flat but is curved) .. so that now the spring is back to almost its original length. Soo what I'm going to do is completely eliminate the bypass capability within the pump by welding the flow piston shut and putting an external relief valve that will flow back into the reservoir. The advantage of an external relief valve of course is that the pressure can be adjusted by simply turning a nut.

This is the relief valve I ordered from NorthernTool -- made by Prince Hydraulics:

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200335623_200335623
Relief pressure is adjustable between 1,000 and 2,500 PSI.

If anyone has any experience with such a valve (a hydraulic relief valve), please chime in as I am new to hydraulics and have never used a valve before. What I'm interested in is the vavel's relief characteristic or behavior. To be more specific, when this thing reliefs, does the pressure go down to say almost no pressure or does it keep a higher pressure (say 1,000 PSI) ?

 

[IZwack]

Some pics of the reservoir..

Internls showing the strainer and a baffle. The baffle is angled so that the returning fluid (which comes from the left side) is forced downwards and away from the surface -- which minimizes aeration.

Reservoir before welding the mounting tab and painting. The bottom 5/8" angled barb fitting is the original one from my old SOHC pump -- the fitting was sliced at an angle using a cut-off disc and welded to the bottom of the reservoir. The protruding tube on the right side is the return line.

And finally the reservoir mounted and its accompanying bracket which bolts it down to the original reservoir holes on the block

 

[BrooklynBay]

What is the cap from? Did you make that too? Ford has a similar reservoir which they make for the Taurus SHO. I have it in my 88 with electric steering. It uses an OEM cap, and fits like a glove. The Ford hole spacing was the same for the reservoir as my battery tray which has a bolt in the corner.

 

[IZwack]

What is the cap from? Did you make that too?

I bought the cap from NorthernTool for $10 (although its available from other places too).
But anyways its a breather cap and comes with the strainer.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_55452_55452

The reservoir holds about 1.5 quarts of fluid -- with the fluid about an inch from the very top of the strainer. It was painted with Rustoleum hi-temp paint (I think meant for BBQ grills and such) because the EGR stuff is pretty close to it.

The weird noise resulting from starving the pump is no more but I still have to install the external bypass (as mentioned in post #125) and get this thing out on the trail.

 

[IZwack]

Removed the pump today to inspect why its pressure was back down and yes the stainless steel #4 washer did cone out. Its hard to tell from the picture below but it was enough to drop the pressure significantly. Its amazing how high the tollerances are, just a minute amount of washer deformation drops the pressure by a few hundred PSI.

The relief valve also came in yesterday but I'm still waiting for some parts before I install it.

 

[IZwack]

Bypass assembly

n-n-n-naked

 

[95exploderboy]

Hey IZ, I'm closely following your build since I am also doing full hydro. My only problem is that I am in a bit of a time crunch for the run at the end of the month and don't know if I will have the time to modify the pump. I was wondering how much you tested and drove it with the stock pump. The guy I am getting my ram from said the setup worked well with a stock cherokee pump so I'm guessing it should be satisfactory with the Ex pump for a run or 2. Do you think I should have any concerns with this? Could it depend on the cylinder size and other factors?

 

[IZwack]

Hey 95exploderboy -- whats going on?

Before I switched to full hydro, I was running a Toyota IFS gearbox setup (that was on its way out) driven by the stock SOHC pump and I could only turn the wheel maybe 1/3 each way with the vehicle sitting still on dry pavement (and tires at about 10 PSI) -- after that 1/3 it just got difficult. Of course steering was cake once the vehicle was moving (even at very low speeds) but standing still on dry pavement was a workout. This is how I ran the Jun '07 Rausch Creek run (you were there) and I would say that the stock SOHC pump with the cylinder I'm running (2" bore 1.25" rod diameter) felt about the same way as the Toyota IFS box setup. So its do-able but standing still is a little iffy.

It defnitely depends on the cylinder size and as mentioned, also the rod size (because the bigger the rod diameter, the less effective the cylinder is actually).

But hey thats great that you're aiming to get your rig out on the trail at the end of the month!!

EDIT -- I should mention that some Jeep TC-series pumps are actually pretty high in PSI .. some are rated to 1,450 PSI stock! CHeck this out:

1350-1450 PSI!

 

[95exploderboy]

http://www.pirate4x4.com/tech/billavista/PR-Hydro_Steering/TC%20Pumps%201.jpg[/url] 1350-1450 PSI!

Hmm... that burst my bubble.... Well if you said it worked but wasn't the best, i'll just run it for the weekend and see how it goes...

also, that link didn't seem to work

 

[IZwack]

Ok sorry about that -- I've updated my previous post and instead posted the image.

Yeah I think your best bet is to just run the stock pump and see how it goes. I mean if its not enough PSI, then its just a matter of swapping in a higher pressure pump (maybe a modified GM one like I was using).

 

[IZwack]

No class today so had a bit of time of daylight left after work sooo..


welded up the flow piston so it no longer bypasses pressure:

opened up the Prince pressure relief valve just to inspect how it works, and its exactly like the flow piston:

annnnd made a bracket to hold the relief valve onto the shock tower:

 

[Burns]

Nice

I would love to go full hydro but its not legal to drive on the street

 

[Turdle]

I am intrigued by the possibilty of this--

 

[IZwack]

What is that? A radiator? Are you sure you posted that in the correct thread?

 

[Turdle]

What is that? A radiator? Are you sure you posted that in the correct thread?

That is a hydraulic powered cooling fan and shroud--
No electric needed-just a thermocouple device to switch flow--
I think it is actually on that one

 

[Turdle]

Sorry-I kind of thought it went with the whole hydration thing--

I guess some vehicles have gone to this-it seems more reliable-