Electric Power Steering in a 78 FJ40. (1 Viewer)

[thecrazygreek]

Removed the lower clamp, pulled the lower shaft cover, removed the two Allen bolts holding the outer lower cover. Lifted that out of the way and found a torx bolt holding the inner shaft pieces together.
Once I undo that I'll be able to pull the shaft apart and mount my flange.
Next up... I need to go buy the proper torx.

 

[78fj40mg]

There's always a way! Great discovery and disassembly work!

 

[thecrazygreek]

Thx... I'm hoping I'm correct on my assumption.

 

[Racer65]

Answer from the factory:

From the EZ unit the output shaft and tube can be removed, first remove the 2 bolts from the output tube, you can then slide the tube down to get access to the clamping bolt from the shaft. After removal of the bolt the output shaft can be removed to get it through the original flange, then install shaft and tube back on the EZ unit. The clamp on the output shaft is used in combination with the clamp on the input tube to get the EZ unit into the correct position after installation.

 

[Racer65]

Will update the install guide.

 

[Sol7]

Hi,
fine, that's an easy solution.
There are at least 2 different versions of the steering column: "Collapsible" and "rigid". Don't know if there are more differences, but the collapsible version has a u-joint, a 2-part shaft inside, it's extensible by approx 1', the flange has a 3-hole pattern and the inner diameter is wide enough that the shaft can be pushed through without disassembly. See attached side-by-side picture of the collapsible column.
During my install I was facing a different issue: Other than the "collapsible" column, the EZ steering has a fixed length between the flange which goes to the gearbox and the mounting holes below the dashboard. In my case it did not match.
After one hour of measure/install/thinking, my solution was to cut and weld the mount in a different position.
Don't know if this issue is specific to my car - the body might sit in a slightly different position since rebuild - but an adjustable clamp instead of a fixed mount on the column would have been nice.

Peter

 

[Coolerman]

Open up the gear box so we can see how that motor drives the shaft!

I personally think this is a much better solution for power steering. A lot of guys don't know how to weld/fabricate, and this is the perfect solution. I bet it will handle 31 to 33" tires for mild 4 wheeling.

Racer65, what kind of steering box will you have to run on the older trucks since they have the one piece column/steering box?

 

[Racer65]

Racer65, what kind of steering box will you have to run on the older trucks since they have the one piece column/steering box?

For the '72 and earlier trucks, it requires a mod to the existing one piece column, and involves cutting / welding. To give you an idea, I will post up a series of photos below. The way we're handling it for a TLC resto is to send the entire steering assembly (including the 3 speed column shifter) to the factory for the fab work, and then have them ship back a ready-to-bolt-on kit. The goal is to develop a kit with a set of instructions for a remote shop to handle the work, but we're not quite there yet.

 

[Racer65]

 

[Racer65]

 

[Coolerman]

That is awesome!

Quite a few changes to make for the older trucks with column shift!

Are you allowed to post pics of the gear box? Still curious as to how that motor turns the shaft while allowing the fail safe function.

 

[Racer65]

View attachment 1197558

That is awesome!

Quite a few changes to make for the older trucks with column shift!

Are you allowed to post pics of the gear box? Still curious as to how that motor turns the shaft while allowing the fail safe function.

There's a shot above. Are you looking for anything specific?
After the TLC project is finished, I'll be able to do a little more show and tell.

 

[toyotaspeed90]

Something to consider - for those who don't already have some sort of alternator upgrade - I do know that a vehicle Toyota sold with and without electric power steering, they did have a larger alternator to accomodate the additional power requirement (2nd gen Toyota MR2)...

Also curious how it will handle something like significantly larger tires (like 12"w+ tires)...

Seems like a pretty darn good option to keep complications under the hood and front of the frame to a minimum...

 

[x463]

I believe these units require roughly 50 amps. Since you aren't turning constantly it's unlikely you'll kill the battery thus the alternator upgrade may not be required.

I went ahead and did it anyway - had the OEM Toyota/Denso rewound. Ended up testing out at 105 amps after. Will be good for other additions to the electrical system as well.

 

[thecrazygreek]

Ok, took apart the Eps shaft and it's what has already been explained. The flange is now where it's supposed to be.

 

[thecrazygreek]

All reassembled and ready to mount into the truck.

On to the electrical!!

 

[Racer65]

 

[78fj40mg]

Good job!

 

[x463]

@Sol7 @Racer65 @thecrazygreek

Any installed photos? Curious how close the electric motor is to the fuse box once installed and how much is visible under dash. Also the EZ directions (at least the ones I have from NL) mention some trimming of metal at the dash opening to make it fit. Is trimming required?

Thanks -

 

[Sol7]

I was not lucky with the 9 o'clock position shown in the EZ installation guide,
so I turned the whole thing by 120° clockwise, see below...

Clearance to the upper clutch pedal was too tight - so grinded away a few millimeters from the (massive) pedal arm:

another view:

See the potentiometer on the right, the ECU sits behind the fuse box. A lot of wires in my case because of 24V system. The EZ system is running on 12V only, so additional Relais, fuses and a battery balancer is required.

Btw: Current draw measured is up to 40Amps under full load (fuse is 40A).
Idle current drops to a few mA.
My estimation is below 5Amp average for normal road use, below 1Amp on the autobahn, but might be a litte bit more when pushing a trailer in reverse gear around the trees in a dark forest...

Peter