820 water pump change

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

820 water pump change

Post by richard moss » Thu Sep 24, 2009 1:13 pm

Apologies for the pics - some are less than 100% brilliant.

The most common reason for having to change the pump is the failure of the seals around the shaft, leading to water dripping through the drain onto the aircon pump (if fitted) or straight onto the ground. The good news is that the failure is usually progressive, rarely catastrophic and it's an easy component to change.

The T series water pump is a superb piece of design - it's attached to the back of the PAS pump and can be changed without having to release the drivebelt and can usually be done in under an hour. The only problems are likely to be a lack of access due to the exhaust manifold/aircon pipework (not too bad) and the tendency to for the securing bolts to seize up. With that in mind, soaking the bolts with penetrating oil for a few days in advance will help, as will using a 1/4" drive socket set, several extension bars and hexagon sockets for a nice tight grip.

The picture below shows the pump outlet with radiator hose attached. This plate sandwiches the pump against its mounting and the bolts go through the outlet and pump into the mounting.
Image

The first thing I did was jack up the car and position a bucket underneath to catch the escaping coolant (so that I can reuse it as the anti-freeze is fresh). The I undid the clip on the hose from the pump outlet and release the hose.

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

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

Re: 820 water pump change

Post by richard moss » Thu Sep 24, 2009 1:13 pm

Once the hose had been released, I removed the 8mm bolt securing the aircon pipe to the metal coolant rail to allow me a little extra room to work.

Image

Then using 8mm sockets, spanners and extension bars the 5 pump mounting bolts can be removed. The two rearmost ones are best accessed from behind the exhaust manifold with sockets, the top and front ones with spanners and the bottom one with a socket in front of the manifold. Do this with the engine cold!!!
Image

The outlet plate can be removed, at which point a little water will escape, and then the pump can be levered off, at which point quite a lot of water will escape. With the pump removed you will see the drive dog on the back of the PAS pump - and this area will probably need a good clean out as water will have been getting in.
Image

Once removed, the old pump showed clear signs of a leaking seal and corrosion of the drive dog.
Image


The back of the outlet plate was pretty manky so needed a cleanup with wet and dry paper.....
Image
Image

and then the new pump could go on....
Image

but before fitting I used a thin scrape of instant gasket to hold the 3 rubber "O" rings in place. Note that these are shaped to fit the pump and need to have their flat face against the pump body.
Image
Image


The new pump slotted into place - you just need to rotate the pump impellor as it goes in to enable it to engage with the drive dog......
Image

the outlet plate refitted......

Image

and the 5 x 8mm refitted and torqued up to 7nm. As my torque wrench didn't go that low, I did them up by feel to "comfortably snug"....
Image

After that just reconnect the radiator hose, refit the a/c pipe securing bolt, refill with coolant and after starting up check for leaks.

Including tea break and taking photos the whole job took 55 minutes
1990 827 Sterling manual
1990 Jaguar Sovereign 4 Litre on LPG
1969 MGC GT (currently hibernating)

User avatar
lakesrally
Posts: 423
Joined: Fri Nov 28, 2008 1:00 am
Location: Lake District, UK
Contact:

Re: 820 water pump change

Post by lakesrally » Fri Sep 25, 2009 5:07 pm

Well done Richard. great, well detailed, post. Of no use to me as I do not have an 800 series car but I thought you should be told.

Regards
Stewart Devlin
1925 16/50 5-seat Tourer
1933 14 Pilot Saloon
1949 P3 75 Saloon

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

Re: 820 water pump change

Post by richard moss » Fri Sep 25, 2009 10:01 pm

Thanks Stewart, I'm pleased to say that it has been useful to a couple of people on rover800.info - as has the cambelt change one.

Half the time a job looks worse in the manual that it is in practice - these sort of "How to" threads can demistify the process.
1990 827 Sterling manual
1990 Jaguar Sovereign 4 Litre on LPG
1969 MGC GT (currently hibernating)

User avatar
lakesrally
Posts: 423
Joined: Fri Nov 28, 2008 1:00 am
Location: Lake District, UK
Contact:

Re: 820 water pump change

Post by lakesrally » Fri Sep 25, 2009 11:12 pm

I've just done something similar on the rebuilding of the water pump and fan for the 16/50 but decided not to bother boring half the world with it as there only a handful of these cars left and most of the owners are not on here, in fact I'm not sure if any are, so I am going to send it out to them on a CDROM. Your efforts though are much more likely to reach an appreciative audience.

Regards
Stewart Devlin
1925 16/50 5-seat Tourer
1933 14 Pilot Saloon
1949 P3 75 Saloon

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

Re: 820 water pump change

Post by richard moss » Sat Sep 26, 2009 12:21 am

Don't be bashful - post it all up! One day, 5 years from now, someone browsing this forum will need that information.
1990 827 Sterling manual
1990 Jaguar Sovereign 4 Litre on LPG
1969 MGC GT (currently hibernating)

User avatar
47p2
Posts: 694
Joined: Wed Sep 24, 2008 7:51 pm
Location: Glasgow
Contact:

Re: 820 water pump change

Post by 47p2 » Sat Sep 26, 2009 7:12 am

Stewart, I have to agree with Richard. It should be posted here in the forum for all to see

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

Re: 820 water pump change

Post by richard moss » Sat Sep 26, 2009 4:14 pm

I wonder if there should be a dedicated tech section where the posts can become a kind of reference library?
1990 827 Sterling manual
1990 Jaguar Sovereign 4 Litre on LPG
1969 MGC GT (currently hibernating)

Shaunburns
Posts: 1
Joined: Wed Mar 20, 2013 11:55 am

Re: 820 water pump change

Post by Shaunburns » Wed Mar 20, 2013 12:29 pm

Hello

Wonder if anybody has any thoughts on the problem I'm having, I have an mg zr with the 2.0 turbo t series from a 820, the head gasket went about a month ago so I had that replaced along with a recon head, before it was done the coolant system was building up too much pressure and ended up dumping it all after a long drive, but It still ran perfect, now though its
Running very rough, seems to have lost power and struggles to start, and the water pressure is building up and overheating within about 2 minutes of starting, I have noticed a very small leak around the back left hand side of the engine but can't really see where it's coming from, I have no coolant/oil mixing, only thing I can think of is the water pump but I believe that's at the front left hand side?

I appreciate any thoughts or inputs

Thanks

Post Reply