Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: ctaylor738 on February 11, 2023, 13:51:51

Title: Electric Power Steering Installation Completed
Post by: ctaylor738 on February 11, 2023, 13:51:51
I'm proceeding with the install of electric power steering from EZ Electric Power Steering in a euro 280SL with manual steering.  The unit arrived a couple of days ago.  It consists of a complete column with the motor installed, a control unit, several wiring harnesses, an adapter to connect to the speedometer cable, and 113-specific instructions.

It looks like a very complete and high-quality setup.

The steering box in the car has a huge amount of play and will be replaced as well.

Looks like an interesting project, stay tuned.

Cheers,

CT

Title: Re: Electric Power Steering Installation
Post by: 450sl on February 11, 2023, 19:51:20
Hi Chuck, very interesting. : let us know how you get on..

Mark
Title: Re: Electric Power Steering Installation
Post by: Jack the Knife on February 11, 2023, 21:02:13
Good luck, will follow this with enthusiasm.
Title: Re: Electric Power Steering Installation
Post by: franjo_66 on February 13, 2023, 22:15:18
Thanks for sharing Chuck
Will also be following intently !
My manual steering is becoming more of a chore each day.................
Title: Re: Electric Power Steering Installation
Post by: Cees Klumper on February 14, 2023, 02:25:51
Looks very solid.

Do you have to send back your old steering column, so they can use it to make another unit?
Title: Re: Electric Power Steering Installation
Post by: ctaylor738 on February 22, 2023, 17:27:45
We're away until mid-March, so I won't be able to start on this for another month or so.

EZ offered a used steering column for the conversion for 450 euros, or we could have removed the one in the car and sent it to them.  We went with the first option, since that will reduce the time the car is off the road, and allow the car to be converted back to manual steering in the case of an "as built" restoration. ::)

Cheers,

CT
Title: Re: Electric Power Steering Installation
Post by: ctaylor738 on March 07, 2023, 03:16:38
Here we go.  The dash is apart and the old column is out.
Title: Re: Electric Power Steering Installation
Post by: ctaylor738 on March 09, 2023, 05:55:01
Moving ahead, the new column is installed under the dash, no issues with fit.

Title: Re: Electric Power Steering Installation
Post by: ctaylor738 on March 27, 2023, 22:27:12
The system is now operational and works as advertised.  My friend and partner Ray did the install and offers the following comments:

One (general) - There was no wiring diagram, just the direction, "Connect all plugs belonging to both the computer and steering column."

Two - The car has air conditioning. The evaporator takes up the space under the glove box, so the ECU will not fit in the directed location. I mounted the ECU on the cabin-facing side of the air distribution box for the car's heater, over the transmission tunnel, with the wiring facing up. That was possible on this car because there was sufficient  space between the heater box and the back of the A/C evaporator case. Only two mounting screws were used to not interfere with the operation of the heater internal distribution flap.

Three - It was difficult getting the new steering column to move sufficiently to the right to engage the two retaining bolts from the dashboard. Interference came from the power steering column-mounted motor attachment contacting the left side of the heater distribution box. I needed to move the column assembly about 10mm to the right to engage the left support bolt (front-to-rear slot, the right bolt is slotted side-to-side and was not a problem.) Applying a little side force on the column allowed the heater box (plastic) to distort just enough, and, combined with modifying the bolt (using a grinder, tapering the mounting bolt to a cone on the engagement end), to allow threading into the (welded) receiver nut. Note that the left support nut is completely accessible (the right nut is not) while doing this, so, it might be best to leave this nut loose and slightly enlarge the slot.

Four - With the adapter, the speedometer cable barely clears the windshield wiper linkage.  We have pointed this out to EZ Power Steering and suggested that the tube be shortened.

Cars without power steering had a steering ratio of 22.8:1 (4.1 steering wheel revolutions from left to right) the cars with the factory power steering had a ratio of 17.2:1 (3.2 steering wheel revolutions from left to right).   So while the system allows the car to be easily maneuvered at low speeds, at higher speeds the steering seems a bit ponderous with the combination of the power assist and manual steering.  If you desire a sportier feel, you might consider using a sealed-up power steering box.  We also pointed this out to EZ, suggesting that they offer this as an option.  C&M Hydraulics confirmed that the worm from power steering box will not work in the manual box. 

EZ further commented:

"Please note that if you decide to use a hydraulic steering box (without the pump) that we recommend connecting the in- and outgoing hydraulic lines with each other so the oil can still move freely from one side of the steering box to the other.

Please note that the Powersteering box has a torsion rod to determine how much assistance (and to which side) the assistance must be given. When the pump is not connected this torsion rod will give a minimum amount of play, some sporty drivers have it welded so there is no play whatsoever."

That's it.  We'll continue to follow the car and report.

CT
Title: Re: Electric Power Steering Installation Completed
Post by: franjo_66 on March 27, 2023, 23:16:59
Great work Chuck !
Thanks so much for sharing the journey and providing the insights to some of the challenges encountered.

Title: Re: Electric Power Steering Installation Completed
Post by: Tomnistuff on April 24, 2023, 21:55:33
Hi, Chuck,
In your last post, you used the word "ponderous" in describing the combination at high speed of electric power steering and the 22.8:1 steering ratio of the non power steering 280SL to which the electric power steering was added.  To me, ponderous would  be like "a bit too much steering wheel turning required compared to the much lower turning required by the electric power steering".
I guess what I am really asking is for a clarification of the use of the word "ponderous".
I will probably add electric power steering to my 66' 230SL this summer and would like to understand the possible "surprises" I might expect.
Thanks,
Tom Kizer
Quebec, Quebec, Canada