Alternative 800 expansion tank

Post Reply
User avatar
richard moss
Posts: 233
Joined: Wed Sep 24, 2008 5:23 pm
Location: Wolverhampton

Alternative 800 expansion tank

Post by richard moss » Thu Sep 24, 2009 1:15 pm

Copied from one of the Rover 800 Yahoo groups. Thanks go to Paul Kenny for the research and information.

As we know, the Austin/Rover original coolant tanks are dodgy at best and the replacements can be worse and often require a bank robbery to

Our Sterling cracked a tank over a year ago. I installed one out of a
Volvo 740 using a Volvo 14psi cap (Same thread as Rover but an awkward shape). Worked great under all Aussie conditions. My son then bought a parts car which had some spare tanks included.So, for originality we swapped back to Rover. Two more split tanks later and we found what we consider a great solution.

Use the VOLVO 1993 -850 Tank with 14psi cap.VOLVO PART NUMBER
7365089-001 (Ask for the one without the sensor hole if you don't have
the LCW light in your 800.Im told you could get the Volvo sensor type
and splice it into the Rover one) They are readily available new and
used and are cheap. The outlets are in good positions, I only had to
re route the bigger hose and put a short extension on the overflow
hose. At most, you need to drill two holes in the inner guard for
bracket. I mounted ours using an adjustable battery hold down (mounted
sideways) but you could also grab the original slide on Volvo bracket.

There is no reason not to use the 16psi Rover Cap, I just figure a bit
less pressure on the system is a good thing and the car doesn't notice
the 2psi difference at all. These Volvo tanks are used in another
model that runs at around 20 psi so there is no issue with over
pressure. Ahh a nice NEW tank- I no longer drive with one eye on the temp gauge! I reckon if it works here, it should work anywhere in the world.

The relevant pics are in :- ... 7/pic/list" target="_blank

A pretty neat solution I think."

Photos reproduced here:


1990 827 Sterling manual
1990 Jaguar Sovereign 4 Litre on LPG
1969 MGC GT (currently hibernating)

Posts: 1
Joined: Thu Dec 23, 2010 5:43 am

Re: Alternative 800 expansion tank

Post by Sadi21 » Thu Dec 23, 2010 5:47 am

Very good information thanks

Posts: 3
Joined: Thu Feb 17, 2011 10:17 am

Re: Alternative 800 expansion tank

Post by bradphil » Thu Feb 17, 2011 10:25 am

I encounter this last 2 days ago with my Rover 800 825 Sterling. I just brought it my a car center and he offer me a sterling parts tank to replaced with. A little bit pricey but i dont have a choice...anyway thanks for the info..

Posts: 105
Joined: Sun Mar 04, 2012 5:35 pm

Re: Alternative 800 expansion tank

Post by jefflee » Thu Aug 11, 2016 8:02 pm

Hi, Can anyone tell me the part no. for this Volvo header tank, is it 9141095 ?
1937-20 SS _ 1938-20 SS _ 1946-16 SS _ 1947-16 saloon

Post Reply