Steering Rack

[stevejgreen]

Re: Steering Rack

The Marina Roadster was built around the rack, I'm afraid it a nose-cone off job, and for some the engine side panels too.
If you replace the rack, make sure it is like for like as Mk1 and Mk2 racks are subtly different with different mounting bushes.

[Blue Marlin]

Re: Steering Rack

Thanks Steve, I feared as much.

I do have a new rack so I will crawl over it and make sure they are the same. Just my luck they will be different mks!

[Blue Marlin]

Re: Steering Rack

Hi Steve,

Sods law, the racks are indeed different .

Are you able to tell which is which from the attached pics?

Regards

Derek100_0612.JPG100_0613.JPG100_0614.JPG

[lil_red_roadster]

Re: Steering Rack

Try measuring them - the early rack is, according to the Earlpart catalogue, 0.25" longer (40.5 vs. 40.25).
Failing which I'm sure Steve will come up with the other part number...21H542 can be seen above as the one fitted.
I found a TS-542 online but it specified it as for the entire run from 1972-80.
Mine is a 542 but the donor was a '74 MK1 estate which, somewhat inconsiderately, used a mix of MK1 & MK2 parts...so that doesn't help us much..!

[dcunn]

Re: Steering Rack

As ever, just thought I'd try to help by looking at mine - donor was a "P" reg 1.8TC - and it is different again .

[stevejgreen]

Re: Steering Rack

I am on my travels today. If you look here or there you will find the workshop manual section on steering. It includes some of the differences between the Mk1 and Mk2 racks.

[andyf]

Re: Steering Rack

If the nylon bushes keep wearing out con't you fit phosphor/bronze ones instead?

[stevejgreen]

Re: Steering Rack

I suspect that the issue is not with the standard bushes originally installed, but with the methods used to allegedly recondition the racks, quite possibly simply ignoring the bush completely, taking a worn rack, and simply cleaning it up. It could be that solvents used in the cleaning process exasperate the failure rate.
A phosphor bronze or sintered bush could easily work, if you could find a manufacturer or a standard part that would fit. The downside might be extra noise or vibration.
I am not in a position to develop the idea further, but if it could be done with standard parts the it could keep ageing cars on the road.

[Blue Marlin]

Re: Steering Rack

Found this Mot pass, but excessive play in steering rack ball joint.

and answered myown question. Mk1 fitted and Mk2 replacement (TS542). Apart from position of mount rings and (small) difference in length there seems to be no other differences. If I sourced a Mk2 mount for the OS can anyone think of a reason why this rack can't be used.

[tony.branson76]

Re: Steering Rack

The usual problem is the space between the rack and the radiator.
The steps are:
1. remove the steering column (it seems you have probably done this)
2. Loosen the track rod end lock nuts
3. split the taper joints at the end of the track rods, if they are recalcitrant taking the chill off with a gas torch may be necessary.
4. remove the track rod ends, count the turns so you can repalce them reasonably accurately.
5. wind the offside track rod in as far as it will go, you should then be able to shift the rack towards the nearside and get the remaining track rod through the body work so you can lift the rack out.
How much you have to move the nosecone and radiator forward seems to be different on each of my 3 roadsters.

[Blue Marlin]

Re: Steering Rack

Thanks Tony,

Beasted in and took nose cone and radiator off competely. Will push car out of the garage (tiny) and remove the rack soon. I'm going to fit the rack I've got and suck it n see. I wanted a good look at the old rad anyway!

[stephenlilley]

Re: Steering Rack

I replaced my steering rack today. I replaced a Mk2 with a MK1 and as the latter is shorter I used Spitfire track rod ends as they are longer. the whole process took around 3 hours. I didn't have to remove the nose cone. I used the process Tony has stated and all I had to do was to loosen the Rad and remove the top hose, push the rack to the near side and it lifted straight out. I think many Marlins will be different and this may well not work for all.

[stevejgreen]

Re: Steering Rack

Just for others, were the rack supports different sizes. Superflex now advertise two variants.

As far as I know the chassis dimensions are the same accross the entire range of Marinas and Italy's, so steering and suspension components should fit any model. The longer track rod ends will give greater thread engagement but I'm yet to be convinced if it's significant.
As far as I can determine the significant difference in racks, apart from 'value engineering' seems to be steering lock reduction. This may be associated with the introduction of radial tyres and reducing tuck-under on full lock with crossplys.

[Blue Marlin]

Re: Steering Rack

100_0614.JPG
The new MK2 rack I have has 2 different sized ends on it. The O/S is 35mm and the N/S is 29mm, whereas the MK1 is 29mm on both sides.
Rather large difference in price for MK2 SuperFlex bush kit also.
I am now in the process of odrering a replacement MK1 rack as I feel this will save a lot of mucking around with mounts and rubbers etc.
Nice shiny MK2 rack will probably be getting posted for sale when the dust settles here.

[stevejgreen]

Re: Steering Rack

All useful info. I might try and collate it all when I slow down on my European tour.

EDIT Now here or there