Jump to content

620 power steering?


sandcarsunltd

Recommended Posts

I like Redeye like to keep my 620 stock looking inside and out as much as possible. I'm still tempted as I have a welder friend who takes on removable projects, but won't he won't spend the time/effor on mobile ones away from his shop.

 

So let's see if my brain absorbed all tasks correctly for a possible "to-do" list for this conversion. It may still be do-able for my 2 wheel drive 620!  

 

A) Need an early 280ZX or 200sx steering box (prob like the one on my 80 200sx? No I'm not going to rob Peter to pay Paul ;)  Will have to use 620 Pitman arm and flip it 180 degrees. Might have to have a tab welded to frame, or make an L bracket to frame, for 3rd mount hole to be utilized for strength. (Will have to acquire this box when one lands in a jy nearby.

 

B) Need a 720 PS steering column with flex joint, and rag joint for adapting. But don't need any switches or clam if I can sleeve it. Will still be able to use 79 620 ig/turn/hazard switches and clam shell if sleeved.   

 

C) Need the early D21 pump and reservoir (remote reservoir or combo.)  The attached/detached reservoir depends if I can fab a bracket, fit it below smog pump without hitting steering box or dragging the ground.

 

D) On a 2x4 620 will there be steering linkage issues like: hitting the pan, or need to flip any linkage? Or is that only for 4x4?

 

E) Am I leaving any parts out, or mods needed?

  • Like 1
Link to comment
  • Replies 55
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

No the 620 pitman arm goes on the same. The 280zx box has the arm facing to the front but the steering is behind the wheels. The 620 has the steering in  front of the wheels so it goes on 180 or facing the back. Draw a diagram and it will all be clear.

  • Like 2
Link to comment

Just put a 720 front frame clip on your truck And then you have the vented rotor disk brakes the power steering and steering column.

 

My brother and I have fabbed 9 different columns for my 520 and then swapped frames and fabbed 2 more columns for it.

  • Like 1
Link to comment

I already have a 79 620 with new disk brakes. Next time it needs brakes I might consider upsizing. Nice tip Charlie.

 

When you go to the 720 rotors and calipers do you need to use  different master cylinder, or one with a larger bore? &/or a bigger vac booster?

The 78 & 79 620s and the early 720 with the non vented rotor are a bolt on upgrade to the later 720 early D21 vented rotor disc brakes.  All you do is change the spindle, rotor, caliper and left and right brake hoses to upgrade to the vented rotor and larger caliper brakes.

  • Like 2
Link to comment
2eDeYe" post="1560853" timestamp="1524842152"]It bolted in a bit hack. But it wasn't in the best position. The rag joint setup I used at the beginning did not last either. 

 

I redid it later and sleeved/welded the end of the 620 column on to retain the stock column surround and ignition location. I changed out the rag joint to a u-joint slip shaft. 

 

The finalized column stuff starts on this page of my build thread.

 

http://community.ratsun.net/topic/35996-1978-620-king-cab-4x4/page-50

 

Great photos in your build thread of the sleeved column! Looks doable.

 

Yesterday I found local a complete standard 720 steering column, and a 620 outer tube to sleeve it, a d21 Pump w attached reservoir, and another w remote res. Have to wait for a Z to hit the yard.

 

Do you have a pic of the 80-83 yota steering universal joint looks like? Drove 80 miles to see the only 80-81 yota listed in any jy, was dissapointed to find it had a torn rag joint. Maybe the yota had a standard and ps model like the 720’s?

 

  • Like 2
Link to comment

Redeye, did you use a standard 720 steering column or a 720 power steering column that you welded the 620 sleeve over?

 

 

I don't think there is any difference. 

 

 

 

Great photos in your build thread of the sleeved column! Looks doable.

 

Yesterday I found local a complete standard 720 steering column, and a 620 outer tube to sleeve it, a d21 Pump w attached reservoir, and another w remote res. Have to wait for a Z to hit the yard.

 

Do you have a pic of the 80-83 yota steering universal joint looks like? Drove 80 miles to see the only 80-81 yota listed in any jy, was dissapointed to find it had a torn rag joint. Maybe the yota had a standard and ps model like the 720’s?

 

 

Thanks.

 

 

I don't but it ends up looking like this one. 

 

IMG_3624.jpg

 

 

 

I couldn't find one either which is why I built mine from the 2 rag joints lol. 

 

vIMG_3614.jpg

 

 

I would recommend buying a new one. :D

  • Like 2
Link to comment

I found out 720's have both standard and power steering columns, and the power steering column I found had tilt wheel and different column linkage than the one in Redeye's . I ignored it and matched up the manual column to the one in your pics. I have pics, but did not have time to upload at home, sorry.  Work IT prevents me from doing so at all.

 

If I could find the specific Toyota vehicle it came off I surely would consider buying a new one vs. re-working gnome sized u-joints, lol. I measured the existing steering shafts and I came up with 11/16" dia on the splined shaft end with a 36 count on splines. But I don't have a steering box to measure the input shaft. I'm guessing the steering box shaft would be the same size shaft???

 

There is a company called Borgeson that makes aftermarket universal steering couplers, but they don't make one with that measurement on both ends of the universal joint for some reason. It is either larger, smaller, or smooth bore. And they start about $70 each. If I was sure the steering box input shaft measurement was the same, I could contact them and see if they'd assemble one with that same measurement on both ends since they already have one end that is the correct size.

 

It looks like the tiny u-joints are slightly tabbed or staked. When you were disassembling and reassembling them  did you find they came apart and reassembled easy without ruining the caps?  I thought I'd try to hammer back the tabs first with a small punch, then see if I could press them out with a vice vs. hammering them?

 

There isn't a lot supporting that steering column besides the base bolts around the flat rubber sheet with outer rubber tube (does that thing flex?), and the two sheet metal screws on the bottom of the dash. Do you think back in the 70's Nissan had any thoughts about steering wheel collapse in an accident?

 

Am curious about solid plate steel as your choice to plug the hole vs.rubber, sheet metal, fiberboard, etc . I'm guessing your choice is for column support for HD  4x4 and monster tires vs. a stock 2x4?

  • Like 2
Link to comment

DZM,

Noticed you installed your PS pump on driver side where smog pump normally bolts up. Since you said you can't shorten the original pressure hoses I'm guessing you must have sourced a different pressure side hose from something since you didn't have to use the long metal lines  to cross over under the radiator?  Do you recall what vehicle you sourced them from?

  • Like 1
Link to comment

Check out page 32 of this Borgeson catalog. From what I read, it looks like there are a number of options of what we could use to mate to the steering box. Also check out the joints. There appears to be a number of them available in the same spline - collapsing shafts as well. 

 

You don't need to use the 11/16"-36 spline to the shaft connecting the steering shaft to the box, you can use a joint that has 11/16-36 one side and anything else on the other. 

 

http://www.borgeson.com/Images/09Catalog.pdf

  • Like 2
Link to comment

The 720 shaft and the steering box I used had the same splines. 

I just pressed the joints apart and cleaned up the stake marks before I pressed them back together. 

 

 

 

For power steering lines I just used ones from a hardbody pickup, of coursed it helps that I have a hardbodY KA already. :lol:

  • Like 1
Link to comment

Right on Lee and Redeye for finding that link with the right universal specs!    I must have accidentally linked to another website with Borgeson products,  because the one I was looking at was different.   (If I had a welder and could remember my welding skills your solution would have been just as easy Lee.)

 

I'll see if I can post some pics later of the two different columns I found.

 

The 720 standard steering lower column shaft is solid and uses a rag joint on the lower end, and is connected by a universal joint up top. This one is already loose and has rough bind/rough spots in it, so I didn't want to reuse it. And I really don't want to gamble on another one from the JY.

 

Also, there is no adjustable sliding splined piece on the standard column like the one in Redeye's pic. But I did capture that piece from the other 720 with PS in the JY, and they didn't charge me for it. The lower u-joint in that one is still tight and has equal resistance in all directions, so I don't mind re-using that one in the upper position that is straight and has no angle to it.   

 

Thanks for the tips on hoses R. It really helps when all I know are 620's and the earlier models!

 

Of course there are no Z's in the So Cal yards when I finally need one to mock everything up, and nobody parting one out in So. Cal. Murphy's law! But one will pop up sooner or later. 

  • Like 2
Link to comment

I was at the LKQ in Wilmington last year looking for other stuff, and I saw a 280ZX there with a power steering box. Unfortunately, I didn't know that I needed to be looking for it at the time...until a couple weeks later. Fortunately rebuilt 280 boxes aren't that expensive, from what I recall. 

 

I'll be doing this conversion when I do my SR20DET swap. 

  • Like 1
Link to comment

I used to roam the yards at least once a month, used to see Z's all the time compared to 620's. Now I'm older, so I arm-chair roam the inventory lists till something I'm looking for drops. 

 

Also looked at Rock Auto for inexpensive rebuilds.  AC Delco is a name I respect. Their rebuilts fo for $130. By the time you add shipping, core charge t's $200.

 

Meanwhile I'll work on the rest of the steering conversion system to make sure it works first. And I'll keep my eye on Pick A Part for a gear box at $42 to gamble on for the initial set up. If it works well, or needs help I'll consider the rebuilt.

 

Or maybe I can trade my 5 speed to someone for a nice set of ZX ST wheels for my 200SX and a steering box for my 620? B) 

 

Thought I might make the trek to the Manteca  Datsloco meet in a few weeks just for fun.

  • Like 3
Link to comment

As far as I have found all 720 power steering columns are also tilt columns.  These are found in the deluxe and ST models.

Nissanpartsdeal.com lists one manual steering 6/79 to 6/80 for standard cab 2WD & 4WD with standard steering, and another manual steeringfor 7/80 -_______ which I guess could mean just that year, or means thru the rest of the 720 years?

 

Then as you stated, all the K/C, GL, and K/C 4x4 had power steering. I didn’t look it up, but would assume that means with tilt wheel too.

  • Like 1
Link to comment

Redeye,

I think I answered my own question about your choice of plate steel for the plug vs. another material.

 

Looks like you made a mini-620-sleeve to go inside the plate-steel firewall plug, then built up weld around the mini-sleeve to the plate plug. This would support the inner 720 column tube since it does not extend all the way to the gear box and bolt to it, like the orig 620 column tube did.

 

What I can't tell in the pics, is if you ended up welding/ tacking the inner 720 column tube to the mini-620-sleeve or not? I'm guessing you did, and that is what the V-notches are for in the mini-620-sleeve?

  • Like 1
Link to comment
  • 2 weeks later...

Hey Redeye,

Trying to save room for smog pump &/ or PS pump...Do you recall what vehicle your Toyota steering gear box came out of that bolted on the outside of the frame? Did you have any complications or turning radius issues with it being outside vs. inside? Was curious why DZM thought it might not work, or be ideal?

Link to comment

DZM,

Noticed you installed your PS pump on driver side where smog pump normally bolts up. Since you said you can't shorten the original pressure hoses I'm guessing you must have sourced a different pressure side hose from something since you didn't have to use the long metal lines  to cross over under the radiator?  Do you recall what vehicle you sourced them from?

 

Only one line is under any pressure. The other is just the return to the reservoir. You can't shorten the hose but you can the hard line. IIRC there is a flex line between the pump to the hard line so the engine vibration doesn't break it. I think I just shortened the hard line and used a flair tool and a brass compression fitting. I remember I had to drill the fitting to fit the hard line diameter.

 

Looked like this...

 

parker-compression-fitting-vs68ab9908759

Link to comment

Hey Redeye,

Trying to save room for smog pump &/ or PS pump...Do you recall what vehicle your Toyota steering gear box came out of that bolted on the outside of the frame? Did you have any complications or turning radius issues with it being outside vs. inside? Was curious why DZM thought it might not work, or be ideal?

 

No matter what box you go with, you'll want the inner tie-rod end to be in the same spot. Moving it anywhere will have a huge affect on bump steer and a possible number of other steering maladies. Most pitman arms don't have provisions for a steering link, so unless you're using the Datsun pitman arm, you may as well be guessing how the steering will perform. Unless you have the ability to engineer the proper - or close enough - steering geometry, then have at it. Going with the 280ZX box and stock 620 pitman arm is that you can position the box to retain the stock geometry. 

  • Like 2
Link to comment

I have done this conversion but on a rather radically re designed 620 4 wd. There is a build thread somewhere on this sight that covers it. 

Yota IFS box, Suzuki grand Vitara pump  , Modified 620 column using astro van steering column components, etc. Still working great after 4 or 5 years on the trail. It may not work well clearance wise on a 2 wd....

 

 The L 20 B I used for the pump mock up.

p_001.jpg?1
 
26fb485c110d64b15d17.jpg
 
Column conversion p_002.jpgp_003.jpg
 
 
 
Shortened the 620 column to the fire wall then machined an oil light bushing to carry it 's pass through at the fire wall.
The rest of the column is just Astro van wrecking yard components. 
 
Yota Ifs box.
p_004.jpg?1
\
 
 
I had thought about using the idler arm from the 620 but opted not to for strength. As you can see from this pic. the geometry will work though .
On a 2wd with normal tire sizes it would be plenty strong.
p_007.jpg
 
 
The truck:
p_002.jpg
 
Hope this helps. 
  • Like 4
Link to comment

 

Only one line is under any pressure. The other is just the return to the reservoir. You can't shorten the hose but you can the hard line. IIRC there is a flex line between the pump to the hard line so the engine vibration doesn't break it. I think I just shortened the hard line and used a flair tool and a brass compression fitting. I remember I had to drill the fitting to fit the hard line diameter.

 

Looked like this...

 

parker-compression-fitting-vs68ab9908759

I wouldn't mess around with modifying the pressure line. The pumps run at roughly 1300-1450 psi and a failed line could cause a fire.

'

Build one instead.

 

Pretty sure the threads in the pump are the same as the threads in the Toyota box, in which case, you can buy an adapter fitting to -6AN, then using high pressure hose and re-usable steel fittings from Aeroquip, making a new pressure hose is easy.

  • Like 2
Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.