My Mk IV waterpump is failing: It throws grease and the fan shows some wobbling. Can a standard machine shop replace the bearings? Are replacement pumps available?
Thanks for the help.
Phil
Alan Gibbins in UK has repair kits for the pump. , A much better way than the places who feel they can modify them with modern internals.
In regards the fan , which means the pulley… The bearings may have turned either on the spindle of the body or in the pulley … If the pulley. I think there are bearings available which are one size over in OD . i.e . you use the bigger one of the standard two up towards the front and get the next bigger for the rear.
If the spindle is worn , you may have to get it built up and ground back to size. YO may neeed to check the impellor as the vanes may have rubbed against the body and worn down.
Everything is do-able . it’s only money.
Many thanks for your help. I have sent an email to Mr. Gibbins.
This weekend, I hope to pull the water pump. Is it easiest to leave the radiator, bonnet, radiator shell in place, or remove them?
Thanks for the help.
Phil
To quote the Jaguar Service Manual for all Models1946-1948, p.34 in Section D:
“Water Pump. To Remove.
Remove bonnet and radiator complete. (Operations Nos. 81 and 55)
Remove fan belt, radiator water hose, disconnect by-pass hose.
Remove five bolts securing pump to cylinder block.
Remove pump complete with fan.
N.B.: It is advisable when refitting pump to insert a coil of lead wire under the bolt heads to create a seal against water leakage.
The pump may be removed without displacing the radiator, but in practice it will be found that the operation described is more convenient.”
For the Mark V, I have done it both ways though the shop manual only teaches pulling the radiator first. Leaving the radiator in place on the Mark V while changing the water pump requires the use of more profane remarks and bandaids. Knowing bolt lengths, positions, and parts clearances is important since it is tight and not everything can be seen during the process if radiator left in. Presumably all these caution remarks will apply to the Mark IV also. It will be good to get someone with actual Mark IV experience to remark.
Roger
The mention lead wire reminds me that it was a material called "lead linger"a soft wire which wrapped around the thread , a bit like teflon tape used now by plumbers. It was also used on things like the bolts for the oil filter which went through the gallery where oil was under pressure. Years ago I wrote an article in the CJA mag , from memory titled Lead Lingers Leads to Less Lubricant Loss Later’’ I think I was having a Lois Lane moment. It’s not so much removing the pump with the radiator on , it’s getting it back with the gasket in useable condition , and cleaning the front surface of the block. Removing the rad is not that bad , i did it by the side of the road many years ago when the mills pin in the pump shaft decided to retire.
Perhaps less relevant but in my SS Jaguar the gap between the fan centre and the radiator is only just big enough to get the fan belt through. I can’t remember whether the water pump is held by bolts or studs but if the latter I suspect that I would not be able to withdraw it over the studs without hitting the radiator core.
Peter
The pump is held by bolts. It might be possible to undo the 4 x 1/4"bolts that hold the fan to the pulley, to get that out of the way[ a bit] The MK IV water pump sits a fair bit higher than the SS pump
The trick will be preparing the face of the block and getting the gasket on . And of course, if the pump is coming off to be repaired , the rad off and on , will be only a small part of the enjoyment.
After reading the various responses, I’m going to follow the approach summarized in Roger McWilliams’ post and remove bonnet, radiator, etc. Thanks to all for your help. I especially enjoyed the comments about Lead Lingers and Lois Lane moments! I suppose a resin-cored or flux-free solder would work in place of the lead wire.However, in the past, I have never used any of them and have had no leaks.
Phil
Hi,
I have done it a couple of times, the first “kit” lasted ca. 10 kms before it turned into junk. Then I got the mentioned set of bearings and seals and all is well in that department for 2600 miles. 
It is actually quite easy to take out, although I have a MKV, but I have a MKIV engine in it. Still in most cases easier to take the radiator out of the way.
Cheers,
Pekka T. - 647194
Fin.
Ahhh, that might explain why I had serious trouble getting the oil filter block bolts leak free! In the end I used pipe tape and some permatex on the threads. It would always seal ok in the garage with cold oil, then after ca. 20-30 mins of driving it would start a “drip-drip-drip” type of embarrassing leak. Now it’s ok.
Cheers,
Pekka T. - 647194
Fin.