Steering

Workshop manual data:

Castor Angle = 1 degree positive

Camber Angle = 1 degree positive

Swivel Axis Inclination = 7 degrees

Toe in Toe out- from handbook( is correct) = 1/8th toe out

I asked the list about the correct tracking:

1. I went to get the wheels aligned the other day and found three different settings. The workshop manual for the MK1 FF at section F.6 “Front wheel alignment” says toe in figure is 1/6 inch (one sixth). At F.9 it says front wheel alignment is a toe in 1/16 inch (one sixteenth). The little red book that comes with the FF, under Section J “steering and suspension” says front wheel alignment …………should have “toe out of 1/8 inch (one eighth inch). There appears a conflict on both sizes and on whether it is a toe in or out. Does anyone know the correct figure.

The replies were:

1.The toe in/out figures are meant to compensate for tolerances in the steering and suspension. The early Int/FF’s used a rack made by “Cam”, the later ones adwest, with presumably different tolerances. I do my tracking dynamically, with a drive over device (gunson trackrite), as it compensates for wear/new components, changed ride height due to new/old springs from stock, etc, exactly. The wheels need to point perfectly straight ahead when driving forward, and this the only thing the device attempts to measure.
2. am interested too. BTW, I guess the 1/6 is a misprint. That is not the way they usually give it: Normally it is divisible by 2 to the n’th. Could the other two measures indicate the change from crossplies to radials? I think that happened sometime during ’69 when the Int went Mk 1 1/2.
3. It’s 1/8th toe out. I’ve also confirmed this with Cropredy Bridge Garage

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Photo showing the seized power steering pump.I bought one second hand from Rejen for £50 but understand Rodley Motors ( American parts and service, Terrys Mill, Cutlers Heights Lane, Dudley Hill, Bradford BD4 9PD Tel- 01274 688968) do one brand new for a similar price when I contacted them though they were unable to reference my pump. The steering was however very light ( see list responses below) I was advised that second hand power steering pumps were also often falty and that my light steering could still be due to the pump.

Photo of new power steering pump. I replaced it with a reconditioned pump from Rejen. This is done to order and cost me £195.00 plus P&P (£14.00) Total £209.00. and the steering is still very light. I concluded it must be the rack so thats another job. Finally It has a 5″ diam pulley wheel which uses thinner fan belts. The crank to power steering pump pulley fan belt has been replaced with an American Diesel belt obtained from Regen part no. 2129277 price £11.95 + vat. The power Steering pump was originally replaced under warranty at 2126 miles due to a leak.( Part no. 2196082 ) for six weeks on and off I bought belts to try and get the right size to fit. I’m almost to embarrassed to say the I was adjusting using the pivot bolt for the power steering pump.

My power steering is light. I asked the list:

1. Firstly, my power steering is extremely light. I made a few enquiries and was told that a need to get my rack reconditioned as a ”
peg” inside has “gone” whatever this means? and that this is a common fault of these ” Aldwest” steering racks ( I understand that the early Int/FF’s used a rack made by
“Cam”, the later ones adwest). Does anyone else know of an alternative cause?

2. As some may remember my power steering is very light. Two suggestions as alternatives to a problem with the rack itself were 1) the power steering pump or 2) that the pin that passed through the splined shaft at the top of the valve body on the Aldwest steering rack ( covered by the lower U/J joint) had come adrift. Well I found the pin and all was in order there. Turning to the pump on disconnecting the return line there is a reasonable flow but the only way to discover if there is excessive pressure in the feed line to the rack is to pressure test it by putting in a “tee piece” attached to a pressure gauge. I need to buy a suitable pressure gauge. Does any one know the correct feed and return pressure? so I can get a suitable gauge. I can’t find any references in the manuals to this. Finally given the period system are modern fluids the problem as I am using a universal power steering fluid or anyone any other ideas as to simple checks to confirm where the problem lies.

The responses were:

1.When my steering went light, it was the powersteering pump that was at fault. Here in the USA, that was welcome news, rather than a rack.
2. The power steering on my Mk 1 used to be very stiff yet conversely the car wandered all over the road. Then I discovered that the odd “PAS extra” rack on my car was adjustable!. The first attempt was even more frightening -Talk about oversensitive. I have now just about got it right – it is very light but at least I can now steer in a straight line.
3. I had similar trouble with my Triumph Stag (my other car is an Interceptor MKIII). These have similar racks. What had happened is that there is a pin that passes through the shaft where the steering column connects to the rack, right at the end of the splines. This attaches the pressure control torque rod to the input. If this pin comes out there is no torque feedback and so the steering goes light. The pin is external to the rack and can be seen by removing the UJ attaching the steering column to the rack. I simply put a roll pin in the hole and voila the problem was fixed. Looking at my Interceptor rack, the set up looks the same. If that is your problem, it is really easy to fix. BTW, I have made a couple of mods to my Interceptor steering. One is to replace the two part intermediate steering shaft (with a disk vibration absorber and shaft support) with a single piece intermediate shaft using Borgeson UJs removing the support bracket. For the UJ by the Steering column, I used a UJ with built in vibration absorber. I did this to give more room for tubular headers. If anyone is interested, I can supply the part numbers. It is a very neat set up. I haven’t tested the set up yet, though. Also, I have fitted my Triumph with an externally adjustable steering pressure valve from Heidt’s Hot Rods. This allows me to dial in the steering feel I want. It works well on my Triumph and I will be fitting one to my Jensen.
4. I can’t remember if you said wether it had been light from the start. If so, it may be that you have the wrong setup. The loading in some power assisted systems (including Adwest pow-a-rack I think) is dependent on artificial loading, by means of a small torsion bar in the rack. That bar is specified by the car manufacturer, Jaguar specifying a light one, Aston and Jensen heavier ones. Could that be the “pin” they refer to?
5. The lower end of that central bar should be fixed to the pinion drive mating with the rack. It is pinned with a dowel pin at that end too. So with the control valve still on the rack it should not rotate freely. If the valve is on the bench the pinion should rotate with the bar. If that lower dowel pin has sheared the valve must be replaced. Trying to repair will give the power assistance some truly interesting characteristics if it works at all.
6. the pin sounds like the dowel pin. If it is broken the steering is extremely light, feel-less and transmitt all sorts of nasties from the road. If is worn (or the corresponding holes ditto) the steering will lighten. The Adwest and Alford and Alder valve houses are in some instances interchangeable, athough the housing itself is a bit shorter on the latter. And do check the torsion bar which is connected through the dowel pin. 7. The pin I talked about holds the torsion bar in place. I understood that the steering went light one day and this is not after a new rack or pump. If the rack or pump are new these may have the wrong specs. The torsion bar sets the rack force and hence level of assistance. The pump may have a flow restrictor, or a different pressure relief valve as these are different for different applications. I don’t know the exact pressure for a Jensen, but these pumps are widely used and the pressure should be in the 800 to 1200 psi range. My guess is nearer 800 psi than 1200 psi. One possibility is a stuck pressure relief valve in the pump.
7. Sorry to hear that pin is there. It unfortunately may mean a more difficult problem to fix. The good news is that rebuilding the rack and pump is not that difficult. My guess is that the problem lies with the steering torsion bar in the rack. This is in the pinion housing part of the rack, where the steering column attaches. It is possible also that the pump pressure relief valve isn’t functioning correctly, but that is unlikely. This can be checked with a high pressure meter. I got a surplus 3000psi meter and plumbed it into the high pressure side of my pump to check the pressure. I can’t remember the exact number, but it should be around 800 to 1200 psi. In my case, I had good steering, I just felt that it was too light for my taste. The adjustable pressure relief valve I fitted came from Heidt’s Hot Rod Shop. It was their Adjustable Power Steering Valve PS-101 at $79. (see their web site) They do have installation kits for certain installations, but for these one-off applications it is better to put your own set up together. There are four ports on the valve. The two lower ones are for the high pressure line and the two top ones for the low pressure return to the power steering pump. They are 1/4 and 3/8 NPT respectively. The high pressure input from the pump is an inverted flare fitting (I think 5/16) and the return is a push fit hose (3/8). To install the valve, you attach it to the side of the engine compartment so that the original hoses will reach it. Then you fit a 1/4 NPT to 5/16 (I think) inverted flare adaptor to one of the lower ports on the valve and a 3/8 NPT to 3/8 hose barb fitting to one of the upper ports (use good pipe sealant) and attach the original pipes to the valve. Then a second 3/8 NPT to 3/8 hose barb is fitted to the other upper port and a suitable length of new hose is led from the valve to the low pressure return on the pump. A new high pressure hose is also required to go from the valve to the pump. This has the pump inverted flare on one end and I chose to fit a 1/4 NPT to AN adaptor to the valve and have the other end of the new high pressure pipe fitted with an AN fitting although simply having the high pressure hose end made up with a 1/4 NPT would work fine. I had my local Parker hose shop make the new high pressure hose, for about $20. To adjust the valve, you screw it all the way down and test to make sure all is O.K. Then you gradually unscrew the valve and test until you have the steering feel right, with a good feel on the road and an acceptable level of parking assist.

8.Having dismantled an Adwest pinion to try to understand why one of my cars (jaguar XJ12 based) has steering which is too light, I found that if the pin that connects the torsion bar to the input shaft has failed, the steering will lose assistance, and feel heavy, not light. If the holes that connect the shaft to the torsion bar have ovalled, the steering will have play in it before there is any assistance. However… Per mentioned (in a subsequent message) that he was referring to a pin at the lower end of the pinion, which mine doesn’t have, so I guess there must have been several Adwest designs If you are considering using a pressure limiter to increase the ‘weight’ of the steering, the advice that I got direct from technical support at Adwest (when they still existed) was ‘don’t do it’. The reason that they gave was that this works for ‘average’ driving, but lets you down when you most need assistance. E.g. when you really need to swerve around that moose, the limiter reduces the max flow rate through the rack, and the steering goes heavy.

9When my steering went light, I was told that when Chrysler pumps go “bad” they over boost. So I bought a rebuilt off the shelf pump, installed it and the steering returned to normal. No futzing around with the rack was required.
10 I have used a pressure limiter that is simply an external, adjustable, pressure relief bypass valve. It does not obstruct the flow at all. If you look inside the valve, it has a straight through hole in the high pressure side with a vent into the low pressure side controlled by an adjustable spring. My experience is that it does not affect the dynamic behavior of the steering. The only downside I have found is that when you adjust for firmer driving at speed, you get correspondingly less assistance when parking as well, so the adjustment has to be a compromise between firm feeling at speed and adequate assistance when parking. Now if I could upgrade with speed sensitive assistance…
11)The lower end of that central bar should be fixed to the pinion drive mating with the rack. It is pinned with a dowel pin at that end too. So with the control valve still on the rack it should not rotate freely. If the valve is on the bench the pinion should rotate with the bar. If that lower dowel pin has sheared the valve must be replaced. Trying to repair will give the power assistance some truly interesting characteristics if it works at all.

12) The pin I talked about holds the torsion bar in place. I understood that the steering went light one day and this is not after a new rack or pump. If the rack or pump are new these may have the wrong specs. The torsion bar sets the rack force and hence level of assistance. THe pump may have a flow restrictor, or a different pressure relief valve as these are different for different applications. I don’t know the exact pressure for a Jensen, but these pumps are widely used and the pressure should be in the 800 to 1200 psi range. My guess is nearer 800 psi than 1200 psi. One possibility is a stuck pressure relief valve in the pump.

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Photo1 shows the lower universal jiont. After removing this from the lower splined shaft the pin becomes exposed. It is just a puch fit. Photo 2 shows the pin mentioned in paragraphs 3 and 6 above. In my case the pin was still present. Photos 3 & 4 show the grounding wire that connects the the two sides of the joint.

Photo showing the replacement rubber for the track rod end. I bought mine from Cropredy Bridge Garage. cost………

POWER STEERING RACK

I had to replace the power steering rack because the rack was worn.

It is an Adwest rack and its removal was very straight forward. took me about an one hour to actually remove the rack (plus half an hour to put the car on axel stands remove wheels etc).

The FF rack is not a standard Interceptor adwest rack because the left hand (nearside in England) mounting bracket is angled. That meant I had to take the rack off and get my rack reconditioned. I used Cropredy Bridge Garage.

I undid and removed the two hydraulic hoses where they attach to the power steering rack

I undid the pinch bolt on the lower steering column U/J where it attaches to the valve body of the steering rack. The little pin at the top of the splined shaft partly slipped out and fouled the in the U/J. It took me several frustrating minutes to find out that this was why I couldn’t just slip the U/J off the splines.

I slackened off the lock nut on each of the track rod ends and unscrewed the the the track rod from the end. Leaving the track rod ends attached to the wheel hubs.

I then unbolted the rack from the mounting bracket. I found the t the rack couldn’t be removed whilst the right hand bracket was still in place. I therefore had to completely remove the bracket. Not a difficult job as it is only held in place by three bolts that bolt into captive nuts.

Once the bracket was removed the rack could be partly manoeuvred out of the left hand wheel arch and then down and out under the car.

Photos showing the reconditioned power steering rack number 2 shows the offset mountings of the FF (which I understand can be achieved using the Interceptor rack). The last photo shows the line on the splined shaft that I presume is used to line up the bracket to allow the pinch bolt to be inserted without fouling.

Photo showing the new universal joint to replace the upper u/j on the steering column. The new replacements do not have grease nipples and are therefore maintenance freesteering