Water pump explosion!

Need your opinion/help.

New water pump bearing collapsed ,viscous and fan go ahead impact/destroy my new radiator! “*&!///”


1)car come with a BURGESS pump with more bearing size, looking for
this pump replacing parts but didn’t find , ALL tell me wasn’t original pump.

  1. buyed an original pump with smaller bearing , insert metal fan and new viscous clutch run engine some hours and drived 20 minutes …bang!

here new clutch , older not available.

what you think?

  1. Fred uncorrect work?
  2. uncorrect or faulty bearing ?
  3. heavy metal fan + viscous ?

Hard to say definitively, but it looks like the bearing seized, then freedom then destroyed itself, spitting the rest of it forwards into the radiator.

May be a military engine part? Never seen that size on street car.

This pump appears to be a Series 3 XJ6. There were two versions of the pump. The early used the smaller bearing and the pump body housing is smaller to match. Jaguar started using the larger bearing somewhere in mid production on the Series 3. The shaft size on the larger bearing is larger. If replacing a larger bearing pump with a smaller bearing pump, there is a sleeve adaptor that needs to be used to center the fan clutch as the hole is to large to center on the small bearing. If you do not use the sleeve, the pump can / will be out of balance from the fan vibration and quickly destroy itself. There is nothing wrong with the smaller bearing. All of the XK engines use it into the last of the XKE’s. The larger bearing is the same as used in the later V12 pumps.

1 Like

come in forum later ! try turn car to good way using kindness + knowledge from users.:hugs:

Dears ,used small size pump, small size bearing and pulley come with this pump,
(down in picture), i needed an adaptor to fix fan?

In your opinion what i plan to do? i’m fear to kill another radiator…

Did the fan, clutch and pulley come off in one piece, Fred - leaving the axle intact…?

The very excessive wear on the spindle groove implies wear over time. Was the replacement pump a used, and uninspected, unit - already failing…?

Pulley is a press fit on the spindle(?) - a failed bearing may lock up the spindle to the pump housing and the belt would tear the pulley loose…? What about the lock-screw securing the bearing to the pump housing - was it in place?

xj6 85 Sov Europe (UK/NZ)

  1. yes 1 piece only ! axle ok , bearing only .2 hours working only.
  2. yes a used pump OE for 1s 2.8 , and i add all kit to this chassis (Bearing,seal,gasket, impellor)
  3. lock-screw was in place

what you think ? don’t esitate tell me made bad work!


Measure the hole opening on the fan clutch and compare to the size of the bearing shaft. If not the same, you will need a sleeve adaptor or get one of the larger bearing pumps. We include the sleeve with the small shaft pumps so it can go either way.

Follow Dick Maury’s advice. And, go further, get the replacement from his company. Coventry West.
A USA company circa Atlanta, GA. Well worth the shipping to get it right…

I messed up the pump on my V8. More complex!! Solved with an electric pump designed for the application. Electric fans as well… Much better…



Obviously the assembly just ‘slid’ off the axle, Fred - leaving two initial alternatives. As Dick says; there is a mismatch between the axle diameter and the pulley/clutch - which wouldn’t stand much before detaching…

Or, the fit was OK, but if the axle get stuck, for whatever reason, the force on the pulley with the engine running will tear anything not bolted oose. ll hinges on the pulley - the rest is bolted to it…

One assembling point; the impeller pressed on, and care must be taken to get the clearance between impeller and pump body correct (0,015" +/- 0,003" is given) And that this clearance is not disturbed when the pulley is pressed on…

Whether contact between rotating parts and the pump body will be silent is sort of unlikely - and marks should be visible. And a well fitted pulley should make a slipping belt screech, less the belt very very tight indeed. Which in itself would cause excessive stress on the spindle - overloading the bearings…?

As the event is seldom encountered - imagination has free play…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Thank’you aLL.

Dick you say about a “play” between A and B ?

to all ;

What you do in my shoes ?

I apreciate your help.

Not sure what you are asking here. The bearing shaft is the end that goes into the impeller. Usually a different diameter than the other end. The shaft on the other end of the bearing protrudes and has a given diameter that should match the hole in the fan clutch. If not, there is a mismatch and an adaptor will be needed.

The play referred to is at the impeller end, Fred…

There is no specified play at the pulley end - but there is a warning about disturbing the impeller play when the pulley is pressed on…

None of this explains why the assembly came off - and it should be clarified to avoid a repeat…?

xj6 85 Sov Europe (UK/NZ)

Sorry,3 years work doned 9.4 km satisfaction and depression now.
Sorry, before repeat same bad work …would try uderstand and
Ask more explanation as possible.

Knowledge and courtesy founded here is my only source.

Hipotesis : This is your car Frank , what would you do ?

  1. same kit/same work?
  2. remove viscous ?
  3. change metal fan with plastic ?
  4. remove fan/clutch / add CC 12 v fan to radiator ?
  5. Buy an already refurbished pump ?
  6. ???


Although the question was not asked of me, I’ll offer my opinion, again

Get a refurbished pump from Dick Maury at Coventry West…

I’m a firm believer in “Murphy’s Law”. If a thing can go wrong, it will go wrong. And I have a codicil. " and once having gone wrong, will remain so".

I see it here… do not repeat. Go in a different direction… As suggested above…

Good luck…


1 Like

thank you Carl , thank you all!

already wrote Dick.

apreciate your courtesy and help.

wrote here all next step!




obviously there are different types and shapes around and your problem was that they got mixed up in a negative way.

So, (1) you will certainly not repeat what was so obviously wrong - and, no, I don’t believe that it was you who messed up the job.

And (2) you might try to get things straight on the second attempt. Go to square one with original parts.

Following the SI parts manual you should have viscous coupling RTC1002, if your car is equipped with air condition, and viscous coupling C.28018, if it isn’t.

Interestingly, a major supplier lists the same replacement part for both …

Now, as for the shaft all engines seem to have used C.23417/1

Said supplier lists a replacement part and states that “This bearing is now manufactured with a longer centre shaft than original which spreads the bearing load and increases the life span of the bearing. 5/8” diamter shaft with a full length of 4.875"." BTW, it looks pretty much like the lower one in your first picture.

Finally, the water pump is supposed to be C.28820. It is sold reconditioned, but I’m afraid they wouldn’t take in your Burgess pump … All in all probably around 500 EUR, but still better than having such a beautiful car and not being able to drive it.

Good luck


75 XJ6L 4.2 auto (UK spec)

First I would ascertain, one way or another, ‘why’ the assembly fell off, Fred.

Which may indeed be difficult the main clue is that the pulley/clutch/fan detached as a unit - which means that the interface between pulley and water pump spindle failed. And there is no problem with the unit itself…

As far as I can see; you mated an original pulley to un ‘unoriginal’, or at least different, pump/spindle. While Jaguar usually configured updates/changes to be interchangeable - unless plainly seen as different. But Dick has a point - there may be subtle and unknown differences relating to manufacturers - Jaguar did not make water pumps - or pulleys. Somewhat far-fetched; pump manufacturers may be metric or imperial - and parts would not be interchangeable. Ie, mating a metric spindle to an imperial pulley may not work. Or indeed, as Dick also says, a sleeve would be required if the actual dimension of the spindle was changed for other reasons…

Which also raises the point; a replacement pump as rightfully suggested by Carl, may have the same problem - unless verified ‘old style’ to fit the pulley…:slight_smile:

Question arising; what did you experience when the pulley was fitted to the spindle. It certainly should not just slide on…:

xj6 85 Sov Europe (UK/NZ)

What Series XJ and year is your car ?

the Viscous clutches shown in your pic, the one on the left is from a S1 XJ6
The one on the right is the later item

As alluded to by other, a kit with sleeve is needed to replace the NLA early part with the later VC

In addition, it runs much closer to the radiator…close enough to hit in some vehicles ?

If you need parts, and can buy them from Dick Maury, I recommend that

dear used:

(famous) supplier give NBC2215AA because c.28018 not aviable + c.23471/1 like you wrote.

Viscous are different like Tony wrote more heavy and wide but to my eyes well fixed.