Back to Technical Articles

Steering Box Mount Brace (Mklll)

By Karl Schluter -Low Zep

 

This is a common fault with Mklll’s and even low mileage standard cars can suffer this problem, which is exaggerated with wide tyres etc. The police MKlll’s in the UK, also had a similar fix for this. I have noticed on other Mklll steering box's, the lowest mounting lug is bad for trapping salt etc and corrodes from the inside out, weakening this tab. Do check this while undertaking this job.

 

 

 

 

The mount close to (A1) in the picture is prone to breaking for a number of reasons on these cars. My fix is first to get the tab alloy welded back on. Then have a band 50mm wide and at least 8 mm steel thick bent up to strap over the lower mounts (B). Bend it so under final tightening the bracket is pulled tight onto the steering box mounts (that is with the bracket sitting over the lower box mount, there should be a 3 mm gap between the underneath of the strap and the steering box tab on one side, that is taken up by the final tightening of the strap) this should end up looking like (F1). The strap that covers the lower mounts of the box, I recommend as the easiest of the two designs to make and install with the steering box still mounted in the car. The (F2) 3 point bracket is an improved version that is easiest made up with the steering box out of the car as it is a bit trickier. However, it is worth spending the extra time. A press etc at a small engineering firm and a piece of 2.0-2.5inch pipe to form the brace over, will make the job easier. (A2) shows this 3 point brace in position.

Then a plate should be made (8mm thick (C) )that is placed underneath  the mudguard that covers the mounting points of the box as fitted in picture (D). Be sure to remove any underseal before placing the reinforcing plate (C) into position.

 

You will need to use longer grade 8 bolts and nyloc nuts for the final tightening and remember that these nuts should only be used once.

 

(Thanks Ulf in Sweden for the photo)

 

 

IMPROVED STEERING BOX BRACE.

By Karl Schluter,

 

 

This brace design is in my opinion more effective than just the wrap around brace on its own.

The reason being this brace locates at the extreme top of the main portion of the box, which is being twisted by steering movement.

I myself cannot take full credit for this idea, it turns out early Datsun owners have the same steering box problem.

As a side note, it seems like a lot of bracing just to keep the Mklll box, however as many owners will tell you the box is a nice ratio and steers with nice feel and feedback.

The plates should be at least 5mm thick and use grade 8 bolts with Nylok nuts.

The plate on the box top uses the fixing points of the standard top plate therefore longer than stock top bolts will need used with spring washers. Remember oil will be released once you remove these bolts; a clever person could remove the bolts in an order that keeps the top plate in place while doing the mock up and final install! A cardboard or wooden pattern should be made first, much like I also do for engine mounts etc.

Either side securing plates could be used of the two designed: A, B, or the 1, 2, type that allows for the angle of the box.

 

 

Mock the main box plate (C, 3,) in place and its side plate (B, 2,) and mark where the two met for final welding. The A or 1 plate mounts from the inner guard area.

I would use this brace in connection with the lower strap brace at top of page.

 

Disclaimer: The advice and guidelines given in these articles are given in good faith. The owners and managers of the Galeforce Zephyr site will take no responsibility for any injuries or loss sustained while carrying out the described tasks and procedures or any consequences arising.  Please read the Safety First Article

 

Back to Technical Articles