PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Here is a good thread I used when I was researching the Ram Assist project:
http://www.naxja.org/forum/showthread.php?t=8589&highlight=ram+assist

That thread has links to who sells good hydraulic rams, and what sizes you would want for a single ended hydro assist setup. Also there are links to other pictures of tapped power steering boxes, and how to mod your power steering pump for more flow and pressure. A good research thread.

I chose the 1.5in bore 8in stroke 3/4in shaft ram from www.surpluss center. $84.
I bought my hydraulic lines 3footers with 3/8in NPT and (-6AN) fittings $45 for both, and the saginaw box rebuild kit $50 from www.westtexasoffroad.com

Teh 90 degree 3/8in NPT fittings are normal pipe fittings, Home depot carries that, I got the blue 3/8in to (-6AN) fitting from the local hotrod shop. I should have got the kind that angles down at 45 degrees. look at my pics. the 45 degree would have been better.

Here is a picture fo the rebuild kit.


These are my old seals I replaced.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Before drilling the holes for the Hydraulic lines you will need to fully disassemble the power stering box. Thats one reason to do a full rebuild with new seals and bearings at this time.

1. First remove the pittman arm
2. Remove the 3 steering box bolts holding it to the frame.
3. Remove the high pressure and low pressure line going to the power steering box. place a oil sheet on the floor about a qt of fluid will come out. keep the lines tied up and clean.
4. Remove the shaft from the steering wheel to the box, be carfull the box is heavy.
5. Now work on the box at a clean bench, use pliers to remove the c-clip on the pittmanarm shaft. Remove the top 4 bolts at the other end of the shaft. make sure the pittman arm was centered, then this shaft will pull out. A lot more fluid will spill out, get a bucket.
6. Now remove the LARGE c-clip at the end of the box that goes against your bumper. At the top of your box there is a pin hole push through the pin hole to help get the clip out. Slide the pittman arm shaft back in, and turn it. This will move the big pistion and push the cap out of the end of the box. Now pull the pittman arm shaft out again.
7. Keep turning the steering wheel shaft till the piston comes out of the end of the box. You will probibly hear the bearings fall into the big piston. they will, so dont loose any.
8. Now remove the c-clip at the steering wheel shaft side.
9. With a hammer you should be able to tap the ring (yellow in my pics). The ring has three indentations on it you can tap on. Just screw it out. Then the spiral shaped shaft and the smaller piston will pull out.

10. Now you can drill the holes for the ram. The top hole will drill all the way through. I used an 1/8in bit for pilot holes to keep it centered. The bottom hole only drills half way till you hit the hydraulic line hidden inside the casting. Both holes are 7/16in (look at the pics for locations)
11. Tapp the new holes with a 1/4in NPT tap. The top hole is easy, the bottom hole will only go till the tap bottoms out. Then I cut about 3/16in off the tip of the tap, then continued with the bottom hole till it bottomed out again. The tap was like $6 at Home depot.
12. Clean the box with paint thiner to get all the grit out, then use a air sprayer to get all the metal shavings out. Paint it and stuff. Then put the 3/8in to -6aN fittings on the box using pipe tape.
13. Put new seals on the pistons. kinda tideious. (see pics)
14. Re assemble.

Now some pics of the internals...
All the internal parst:


The large piston, with with spiral shaft in it. The Bearings roll through that little tube you can see in the pic. When you remove the spiral shaft the balls fall into the large piston. I used thick bearign grease to hole the bearings in place inside the large piston. Then screwed the spiral shaft in fromt eh otehre side of the box on re-assembly. The large piston has a new rubber seal under the new puple seal.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

The small piston:

This is three pieces, the splined shaft, an inner sleave, and the outer piston.
Push teh splined shaft out and replace the one O-ring on the inner sleave. Replace the three O-rings and the three purple rings on top of them on the piston. It can only be assembled in one way.

The bottom of the piston sits on the top of the spiraled shaft. They also fit only one way.

This is my 1/4in NPT tap after cutting it shorter.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Drill the holes here:

The top hole is centered to the seam in the casting. The bottom hole will be line with the internal hydraulic line. You can see the hydraulic line very well in this side shot



Pic of the 1/4in NPT to -6AN fittings installed and the box put back together.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Ahh, good tech. That will prove very useful soon enough.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

This pic shows the overall setup, with hydraulic lines and ram.
I put some 90 degree 3/8in to 3/8in NPT fittings on the ram end so the lines would not hit my oil sump on teh engine. I also could have used some 45 degree 1/4in NPT to -6AN fittings at the box to help keep the line furter from the flywheel.

The top port on the box will be high pressure for left turn.
The Bottom Port pushes will be high pressure for right turn.

Box mounted:

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Im gonna mount the ram to my diff cover. My cover is plated with 1/4in on top of the 1/8in stock dana 60 cover. It will hold up.

The ram needs to be mounted so the bolt hole is perpendicular to the tierod. This ram has a 3/4in hole for a 3/4in bolt. There is no bushing for misalignment.

Im trying to decide if I will mount it like this with the hydraulic line comming out the side, or if I should cut the bolt mount off and re-weld it so the hydraulic lines can come in from the top. (Im worried about air getting trapped inside the ram with the lines on the side, aslo better rock protect if they the fittings are on top.)

My tierod is 1.25OD DOM, I am gonna take a piece of 1.5in HREW 120 wall tube and cut a full length slit in it. I will slide it over the tierod to make a large surface area clamp. I will weld tabs for the ram mount onto this sleave. This is better then using u-bolt straps and is better then just welding the tabs to the tierod. Ill get finish pics when Im done. I should have it mounted up tonight.

The ram has about 3/8in more throw then my tie rod, thats only 3/16in in each direction. I dont think that is engough to brake something, I expect the system to have some flex in it, I dont think this could crack my dana 60 kunckles.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

I got it mounted.

I used some 1.5in 120 tube over my 1.25in Tierod, cut a slit to make it into a large clamp. I chose to keep the hydraulic lines comming out the front so Id have better clearance under the draglink.







I works like a champ. Ill have to trail test it this weekend.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

right click - "add to favorites" - save


thanks man! this will be very useful in a month or two. now that you've done it, do you think it would be worth the extra $60 for a ram with heims? how did the box rebuild go for a first-timer? that's the only part that kinda intimidates me...

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

mad maXJ said:

right click - "add to favorites" - save
thanks man! this will be very useful in a month or two. now that you've done it, do you think it would be worth the extra $60 for a ram with heims? how did the box rebuild go for a first-timer? that's the only part that kinda intimidates me...

Click to expand...

Look at my ram mounts. You can see the ram is slightly higher at the diff cover so I have some donward angle on it. This angle will put a twisting torque on the tierod mount and the jam nuts that hold the tierod. If I had a hiem at the Diff cover end It could allow the tie rod end to push down and twist around the tierod. But since I dont have any heims The ram can not shift on me, so it actually is good to not have heims for the way mine is mounted. The lack of misalignment (heims) made it more diffucult to make my tabs, they all had to be at perfect angles.

If I was gonna mountdirectly to a high steer arm I would need the misalignment of a heim. I still could easily weld a heim on the end of this ram if I ever need one...Im sure Ill change my steering configuration, and relocat this ram in future project, but it works great on my current setup.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

ashmanjeepxj said:

This pic shows the overall setup, with hydraulic lines and ram.
I put some 90 degree 3/8in to 3/8in NPT fittings on the ram end so the lines would not hit my oil sump on teh engine. I also could have used some 45 degree 1/4in NPT to -6AN fittings at the box to help keep the line furter from the flywheel.

The top port on the box will be high pressure for left turn.
The Bottom Port pushes will be high pressure for right turn.

Box mounted:

Click to expand...

Ash - two things - ditch those cheesy brass fittings - try the http://www.fittingsandadapters.com/ site for some good steel ones that will last way longer than either the brass or the alum - (you have to be really carefull with torquing those aluminum ones as they can crush the flare or score it causing leaks... The steel will take side loading much better, not leak due to thermal expansion next to the cast box; and are rated to 8000psi

The second item is you have grossly exceeded the bend radius (3" or 4" radius - or bends that are 6" to 8" in diameter are the norm for SAE 100R1 hose) of that hose coming out of the box - If you cannot route it any other way keep an eye out for kinking and the failure of the inner liner - it will just be a matter of time

Finnally (one extra) - if that ram will move across its stroke in that mounting you can ignore this but you really want that thing perpendicular in the horizontal axis to the ball joints/ kingpins and the mounting points to be in the same verticle plane as the ball joint/ kingpin axis (ie: caster angle)

If it is not binding you may be OK but that is putting a fair amount of downforce on that tie rod and eventually into the knuckle... :gag:

Just some observations


Matt

PS - the item you are calling the small piston is the spool / orbital motor for the power assist portion of the box - the steering shaft splines are on a torsion bar that twists that inner collar with the flutes cut in it to actuate the flow of fluid and begin the power assist

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Matt said:

Ash - two things - ditch those cheesy brass fittings - try the http://www.fittingsandadapters.com/ site for some good steel ones that will last way longer than either the brass or the alum - (you have to be really carefull with torquing those aluminum ones as they can crush the flare or score it causing leaks... The steel will take side loading much better, not leak due to thermal expansion next to the cast box; and are rated to 8000psi

The second item is you have grossly exceeded the bend radius (3" or 4" radius - or bends that are 6" to 8" in diameter are the norm for SAE 100R1 hose) of that hose coming out of the box - If you cannot route it any other way keep an eye out for kinking and the failure of the inner liner - it will just be a matter of time

Finnally (one extra) - if that ram will move across its stroke in that mounting you can ignore this but you really want that thing perpendicular in the horizontal axis to the ball joints/ kingpins and the mounting points to be in the same verticle plane as the ball joint/ kingpin axis (ie: caster angle)

If it is not binding you may be OK but that is putting a fair amount of downforce on that tie rod and eventually into the knuckle... :gag:

Just some observations


Matt

PS - the item you are calling the small piston is the spool / orbital motor for the power assist portion of the box - the steering shaft splines are on a torsion bar that twists that inner collar with the flutes cut in it to actuate the flow of fluid and begin the power assist

Click to expand...

Good to know.

I will replace the all fittings with steel ones If I tear it down to swap to a 45 degree fitting at the box.

The ram is mounted as flat as it can for my restraints. If I get rid of the leafs Id have more room to make it flater. The tierod bairly clears the bolt going under the ram, and the bracket on the tierod bairly clears under the leaf.

The doward force cant be that bad. Looking at my Pics My Diff end of the ram is less then 1in taller then at the tierod end, lets just say it is 1in taller. If My ram is 13in when contracted it will have the most angle on it. That angle would be 4.4 degrees. If it continued to push down at a 4.4 degree slope over the 8in of throw, with the mounts not flexing at all, it will push down on my tierod .6 in. There is alittle alowable movement in the ram mounts/bolts, and there is a good amout of flex the tierod would handle before sending a side load to the new king pins. Its a d60.. it'l take it

It dosent Noticeably bind. But Ill have a friend cycle the steering and Ill watch to see If there is any noticable defection in the tierod to worry about.

The bend radius of the hoses, are you talking about the ram ends?
The picture is weird but I will check it. The hoses have a spring you can bairly see in the pics that pulls them against the cross member. So they come down about 8 in infront of the ram, then they bend back and to the ram. Ill check though. I think the hoses have the most bend on them at the box end.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

so...does this setup split the hydraulic force between the box and the ram, or does it use the box as a valve and all the pressure is used to run the ram? does it retain the safety and control of the mechanical linkage?


-looks easy...nice job, great info.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

jjvande said:

so...does this setup split the hydraulic force between the box and the ram, or does it use the box as a valve and all the pressure is used to run the ram? does it retain the safety and control of the mechanical linkage?


-looks easy...nice job, great info.

Click to expand...

yes, no, yes.

my miss conception was that With no drag link hooked up and the ram not mounted I though that the steering wheel woudl turn both the pittman arm and the ram... but that is not how it worked...

With both unloaded and the engine running The ram would fully extend. Id turn the wheel full clock left then when it tapped out the ram would start to contract. So you can not just un hook you drag link and have full hydraulic steering...

With the pitman arm connected to the drag link and the ram unmounted, Id turn the steering wheel like 1/2in and the ram would go fully out then I could continue turning the wheel. If I changed direction the ram would go fully in then I could turn the steering wheel. You can also not just fix you pitman arm and have full hydraulic steering. Your steering wheel would only move like 1/2in in each direction, it would be like on-off steering...

With the ram and the pittman arm connected they are mechanically conneceted so they share the same load.

It was fun to test it all the different ways.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Where did you get the rebuild kit for the steering box? I have checked all the local parts places and they can't get them.

I have a local GM dealer, is there a gm box that uses the same parts and maybe they would have a kit?

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

andyr354 said:

Where did you get the rebuild kit for the steering box? I have checked all the local parts places and they can't get them.

I have a local GM dealer, is there a gm box that uses the same parts and maybe they would have a kit?

Click to expand...

ashmanjeepxj said:

I bought my hydraulic lines 3footers with 3/8in NPT and (-6AN) fittings $45 for both, and the saginaw box rebuild kit $50 from www.westtexasoffroad.com
Here is a picture fo the rebuild kit.

Click to expand...

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Ash-

Yeah - all that stuff was more to take in consideration later if you have any issues :shhh:

The bends I was concerned about were right at the box - I had problems with this in my original setup - the rubber portion of the hose should not make a bend that is smaller than 6" in diameter or 3" radius (that is the extreme limit for 1 wire SAE 100R1 hose - 2 wire stuff needs a larger radius still) 4" radius or 8" diameter bends are better...

Basically you end up with seperation of the inner liner of the hose and even if the external hose cover looks OK the liner can kink and limit flow...

The torque require to twist that little torsion bar and open the spool valve is what prevents you from having a deleted draglink - if you were to chain the pitman arm up you would have semi-hydro steering when you reach the limits of the chain and spring open the valve


jjvande: As far as pressure goes; you are just increasing the surface area of the stock piston in the box by adding the ram (the same fluid pressure is shared through out the entire system) - this allows for more force from the same pump PSI and shares the some load between the axle/ knuckle instead of all at the frame/ steering box/ drag link/ knuckle...

:looney:

EDIT: The rebuild kit is also avail from NAPA ~46$ (last checked ~1.5 years ago)

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

HOLY CRAP!

this is seriously the coolest thread I've seen yet on this board. Thanks for the seriously awesome tech man.

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Very nice write-up. Let us know how it works once you test it out on some trails, Judd :cheers:

Re: PICS: DIY Hydraulic Assist, Box Modifications, Ram selection, Saginaw Rebuild kit....

Matt said:

As far as pressure goes; you are just increasing the surface area of the stock piston in the box by adding the ram (the same fluid pressure is shared through out the entire system) - this allows for more force from the same pump PSI and shares the some load between the axle/ knuckle instead of all at the frame/ steering box/ drag link/ knuckle...

Click to expand...

you can also think of the added ram as just a mechanical advantage, Its hydraulic, but its similar the mechanical advantage of gearing.

Changing your transfercase low range from 2:1 to a 4:1 increases mechanical advantage. With gearing you loose speed to gain torque.
With the steering you also loose responce (quickness) for the gain of added power, but realistically with a 1.5in bore 3/4in shaft ram your speed is minimally impared. A larger flow pump in this system could help increase quickness of the steering.

does that make sense?