Two different size hoses on The green plastic HSMO (Hydraulic System Mineral Oil) reservoir

I just got this XJ40 and have been trying to diagnose a brak problem. I noticed the two outlets on top of the The green plastic HSMO reservoir are different diameters. The two connecting rubbere hoses are also different diametrs. It seems the larger hose was connected to the small outlet and vice-versa as shown in the Pic below. I removed the larger hose from the smaller outlet pipe but I cannot remove the other pipe.

Logically i would think Big to big and small to small but why would someone swapp these around?

Questions.

  1. Am I correct and the lage pipe should go on the lage hose and etc…?
  2. Second does it matter if the hoses are swapped?

I can’t answer your question, mine were big on big, but if you need parts I just converted mine to vacuum assist.

Thanks for the info and the offer David.
I will need new parts as I will be keeping the car.

My 89 factory setup on green mineral oil tank… has Larger reinforced hose towards firewall it had worm drive hose clamp fitting towards front-radiator small hose and mine has spring tension clamp.

Thank you.

I just hope the other end of the hoses are where they are supopoosed to be. It is annoying when you do not know whether a cowboy worked on this car or someone who knows what they are doing.

I am having trouble with my Cruise control also so i may need to buy the Factory Repoair Manual as the Haynes is not detailed enough for my issues.

Thanks again.

I find a lot of valuable info by just searching the xj40 page on this site.

At the green mineral oil brake reservoir the larger hose, with reinforce fabric scrim, the one closest to firewall goes to the LOAD-CHARGE solenoid connected-screwed into the top of VALVE BODY.

The other green reservoir hose, the smaller of the two, the one closer to the radiator goes to the hydraulic brake booster. I’d be surprised if anyone even cowboys switched hoses…
Hope it helps

Dave, what do you think failed on your old hydraulic brake boost?

the accumulater. had a blow out and I could not find one for an 89.

Yes it clears things up for me very well. Thanks.
I have managed to prove that my Accumulator has ruptured by poking a piece of wire into it and the rubber if flat against the top of the bulb. No pressure at all.
I have ordered one from Jagdaim for about $300. This should fix my brakes.

Whole lot more to do on it though. See my Restoration post for more details. My 1988 XJ6 Restoration

I hope you got the right unit as 1990 models the fitting size was changed.

I am getting it fro Jagdaim so they should know as I told them mine was a 1988.

Best to always check part numbers against the VIN, not the model year.

Check here

https://parts.jaguarlandroverclassic.com/parts/index/hierarchy/id/C01/brand/jaguar/

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Thanks. i will try to use this site. After a quic look I cannot see any place to search using the VIN. i will have a closer look at the site later as I am busy now.

You first select the VIN range of your car then click through to the part needed. The final result will show you if there is a variant or superseded part number and that choice will be determined by the VIN of your vehicle.
Sometimes there isn’t a multiple part designation listed, but often there is.

It depends on the type of part selected, however attempting to order correct parts WITHOUT referring to these part catalogues can be a very costly exercise indeed.
Suppliers are generally fairly hopeless without exact part numbers.

Getting the part number or cross-referencing to aftermarket replacements can save you a pile of money (if that is a concern; many don’t care how much it costs) -for instance, brake accumulators that can fit the 40 can vary in price from under $100 to astronomical $$$.

Good luck

Thanks for clearing that up. You are right about saving money by making sure the part will fit when you can’t see before you buy.
I will give it a try.