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Discussion Starter #1 (Edited)
I need to block off the hydraulics going to the height control rams as not only is there an oil leak from the offside ram and a fractured pipe as well.

This is on a 1978 RH drive Shadow 11.

Can anyone tell me where exactly where to insert the ball bearings to block off supply and return. Please do not say "at the rat trap" without a vivid description of which pipe, as all the colour coding has long gone from the pipe bands. Any pictures of the position of the unions to be blocked would be extremely useful.

Another issue is the lower steering column rubber coupling, UR23270P appears to have gone "soft" and when turning the column, the universal joint just below the coupling actually catches the metal work on the side of the subframe.
Has anyone ever had to replace this coupling because of this problem?
Thanks.

Jake.
 

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The rubber coupling gets hot and often splits. It is much easier to remove the two top bolt and nut fasteners that hold the steering shaft on top and the fasteners below to allow complete removal.
I usually add "witness marks" to maintain accuracy when re-installing.
Note: make sure steering wheel is straight ahead.
 

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Hi Jake

Don't use ball bearings as they will distort the seats. Use plugs and caps (available from Kelly).

There is no simple answer to which pipes to block off. The key is to map the hydraulics in your car to make sure you select the correct lines.

I have blanked off the height control on my car but it is a 74 "series 1" and therefore different to your 78 series 2. The principle of selecting the correct lines however is the same.

You will need to map the pipes leaving the rear of the rat trap to the rear of the car via the three, 3-way unions. The key to this is to follow the pipes in and out of the distribution valves. Each valve has a high pressure inlet (from the respective accumulator), a return (to the reservoir) and a high pressure outlet to a brake circuit. The high pressure for the height control is tapped off one of the 3-way unions. It is just a case of removing the rat-trap cover and getting under the car with a flashlight. It is a lot simpler than it sounds.

Then it's just a case of blanking off the high pressure line to the height control system and the return, at the 3-way unions. Undo the pipe, fit a cap and plug the union.

Pic 1 below shows the 3-way unions and the four pipes that go off to the rear of the car. I could not find a pic of the blanked off pipes - will post if I find it.

Pics 2 and 3 are the schematics I made for the upper and lower distribution valves on the 74 SY1.

Geoff
R01.jpg rat trap connections 1.jpg rat trap connections 2.jpg
 

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Hi Jake, I've temporarily blocked off my height control in the past and never went near the rat trap. I didn't use ball bearings because I was concerned that it would be too easy to overtighten the fittings and the ball bearing might distort the flared ends of my pipes. Instead I simply used a few brass UNF 3/8"x 24TPI end plugs. I'm going from memory and this was a few years ago but insofar as I can recall I plugged the pipe end where it enters the high pressure restrictor valve and put another plug in the threaded hole of the high pressure restrictor valve where the pipe had been. I did the same with the low pressure restrictor valve I also plugged the pipe end to the solenoid valve and the hole in the solenoid valve where that pipe had been. I also disconnected one of the wires to the solenoid valve to stop the valve from activating. It's an easy job with the car raised and all the components are relatively close to each other. I think I purchased the end plugs on eBay or online from one of the usual brake pipe suppliers.
 

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My post crossed with Geoff's. Geoff's method looks slightly less complicated and has the benefit of illustrations but either method should do the trick.
 

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I should emphasize that my diagrams apply to the SY1 cars. SY2 will be different - just a case of mapping the lines. Shadow11's method would work for both series of cars.

The third method is to blank off a line at random and drive the car to see if the brakes still work (only kidding).
 

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I would hesitate in using a metal ball bearing due to the risk of deforming the flare or the seat as mentioned by shadow 11.
Kelly has a nice kit to block off lines the correct way and I use it whenever hydraulic work is performed or when components are removed.
 

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PS :devilish: the nicest devil I ever did business with.
 
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