PAS assistance level

[Jake]

Hi There, I've got 2 saloons and both have PAS.
My question is this, are there different racks or levels of power assistance?
The steering to one car is significantly lighter to turn that the other!

[johnnydog]

Actually, that is quite common! I have had several PAS Triumphs over the years, and the feel of the steering does vary - as you say some are lighter then others. This also applies to manual steering as well.
Other factors do come into it - i.e. the efficiency of the pump, tyre pressures / tyre size and steering components (if bottom ball joints, track rod ends and upper suspension strut mountings are new, they could arguably be stiffer than worn joints / mountings that may have certain degree of play in them.) Wear in the ball of the track rods themselves would no doubt create a lighter feel too.
And there are two sizes of PAS steering wheels on the 2500's. Mk2 PI's had a larger steering wheel than the S, which could be a factor too.
I was once told by an 'old boy' mechanic that on the Triumph, an indication that the rack seals are getting worn to the point that they can start leaking fluid into the gaitors, is when the 'steering feel' is very light.
How much truth there is in this, I'm not sure, but whenever I have tried a recently reconditioned or rebuilt rack, the feel always seemed heavier than before the overhaul.

[Jake]

Um, plenty to think about there, I reckon everything is pretty much new in the steering department on both cars.
The other thing I've just noticed looking underneath the car is there seems to be a spectacular amount of oil about on the drivers side, this on the car with the lighter steering! Looks like its spraying out of somewhere? guessing that's another "little" job for the weekend....
Any tips on where they usually leak from might be helpful, i'll need to have a good clean up before I ever find the source as it is at the moment

[Mike Stevens]

Hi Jake,

Try squeezing the gaiters at each end of the rack. The air in each end is vented to the other end by one of the metal pipes. If you can hear gurgling noise when you squeeze one end it suggests that you have fluid in the gaiters - which shouldn't be there!

Also check the pipe unions on both the rack, the control valve and pump inlet/outlet. Sometimes they weep.

The assistance amount is regulated by a control 'hole' somewhere in the control valve. I am led to understand that as this 'hole' gets older, the amount of fluid going through it at high pressure slightly enlarges the hole, with the older the rack the bigger the hole. This then increases the assistance.

Now, I don't really know if this is true, but in my experience older racks have more assistance than newer ones!

It is possible to rebuild a rack and rebuild kits are available, however, a rebuilt rack is a lot easier and they aren't too expensive!

Cheers,
Mike.

[Jake]

Thanks Mike, I’ll be investigating on Saturday
I’ll post an update shortly

[Dave B]

Another thing to check is that the top mount on the front suspension legs are able to turn freely.
The easiest way to check is to disconnect the track rod end and see if the leg turns smoothly.
I once had a PI that needed a lot of effort to turn the steering and it turned out to be the top mount bearings seized!

[Jake]

Hi Dave, I've recently rebuilt the from legs on the white car which is the one with the lighter steering so I know the bushes are fine on that one. What i'd like is if the steering could be a little less assisted on that car. I'm going to have a good look underneath at the leak and mounting bushes etc at the weekend.

[Jake]

Well, I've had a bit of a clean up underneath to help me see what happening. Found the little "plug" bolt (Part number 129242) its in the end in the rack cap for the pinion was only finger tight. I've nipped it up but I don't think there's any hydraulics in there? ALSO the high pressure hose was dripping where is goes into the rack, again I've nipped that up (about a 1/6th of a turn is all) Seems ok now.... The rack and hoses were all replaced about 5 years ago and it has only done about 3,500 miles since.
Also noted there's a "weep" from the front engine seal so guess I'll do that next and keep an eye on it to see I don't get any more leaks!
Should I remove the timing cover to fit the new seal or can I do that in situ?

[Dave B]

The plug serves two purposes, it can be temporarily replaced with a grease nipple so you can grease the rack, also you can centralise the rack using similar to a 3/16" drill to locate a drilling in the rack when its in the central position, helpful when checking tracking etc.
As for the seal, I would say you would have to remove the timing chain cover, which means the radiator has to come off to access the fan & crank pulley fasteners. If its a Mk2 remove the grille as well to improve access, but you'll probably wish your arms were 6" longer. The cover is held on with a mixture of slot head and hex head screws as well as hex nuts. Take a photo before you start to remind you what goes where.
Before replacing the cover, remove the short spacer from the crankshaft nose that the seal runs on, then loosely fit the cover and refit the spacer through the seal before tightening the rest of the fasteners.

[Jake]

Thanks Dave, some words of wisdom in there, obviously a man who has done a few of these jobs before.
I didn't know about the hole in the rack to centralise it!
When I got the car someone else had reassembled it with new rack etc. Tracking miles out, wheel at 5 to 12 etc.
I got it tracked at a local garage then checked it by setting the track rods ends evenly. By counting the turns to remove them ie 5 on the left and 15 on the right (it was that bad) so average 10, sort of worked. Then removed the column and centralised for the the self cancelling cam, then removed and refitted the steering wheel!
Kept me busy for awhile. Might have to check it again now! when I'm not busy.
I thought as much for the seal, Chris Witor mentions it on his web site.
I've ordered the seal, timing chain cover gasket and new PU fan mounts ready for another weekend.
Is there a view on the more expensive leather seals Chris offers if I'm going to change it....?