Hey there,

My new water pump is finally on it's way amd should be herr anytime now. I consulted my German XJ-S repair manual (officially frommJaguar) and have found not a word regarding the water pump specialties. It says to tighten the screws and done.

I have read elsewhere, I think Kirby's book, that certain gaskets require different preparations. The old water pump - was replaced as it looks sometim in it's life - has liquid gasket (mastic/silicone/...) on a paper gasket.

My pump is coming with a newer gasket, one of those thicker 'fibre' style gaskets... Does this require any 'prelubrication' (i.e. treating it with a sealer or so) before I install the little bugger and can then finally seal up the engine?

Any advice about the job?

Cheers

Damien

PS: I've never been excited about a water pump... How low has my life sunk!?

 

I always run a smear, like a dressing, of Hi-Temp RTV on those thicker gaskets.

Not a bead as such, just a finger wipe.

Some say those thick ones self seal, OK, but it it dont, it is not a 5 minute task to redo it.

Last V12 pump I did, I used NO gasket, just a 4mm bead of RTV, slide it home, JUST, let it setup, about 4 hours, then tighten carefully and NO leaks. Basically the RTV sets, makes its own seal, and also takes up any imperfectrions in the mating surfaces.

Works real well on camcovers and trans pans, no gaskets to mis-align, and NO oil leaks.

 

Grant, thanks for your input!

Your tip with RTV was used on my tranny sump. Though I used a fair bit on that - just to be safe

I will fit with gasket but your idea of a smear sounds about like that what I had in mind...

Is there any tightening order to keep in mind? Like over cross? Inside to out? Etc?

Cheers

Damien

 

Daim
I suggest you use quite a bit of Loctite on the bolts and nuts, I had a pump just come undone twice (first time I fitted it, second time a very very good specialist) third time me plus Loctite, no problems since in many years of use. The power steering pump must be loosened at its fulcrum, and at the slider AND at the slider's block fixing or it will not loosen; AND one of the pump studs at that B bank side has to be completely removed to get the pump out. This stud has two uses, one as part of the pump fixings, and secondly as (I think - it was a long time ago) part of the PS pump fixing or slider. Also be careful about torqueing up this stud as it does not go that deep into the block, once again Loctite it.
The new gaskets are much better, but I humbly agree with the WoOz that a smear of copper high temp RTV is a very good idea that cannot possibly do anything but good.
Greg

 

Never swapped a water pump in a V12 Jaguar. I've done more than one in other critters.


In the beginning, circa 1946, we had a choice of four gasket "sealers"!


1. A heavy water pump grease. More to hold the gasket in place than to seal.
2. Red Permatex. I dried to a hard substance and was the dickens to remove the part and scrape of. But, it sealed very well along with a gasket, cork or paper.
3. Black Permatex. It dried to semihard. Much easier to deal with. Also sealed well, but some thought not quite as well as the red. Subjective in my view.
4. Indian Head shellac. Older than the afore mentioned. Dried hard sealed fairly well. Again, with paper or cork.


My approach developed over the years. If both surfaces are in fairly good condition, apply the sealer only to the removal part. Mostly to hold the gasket in place while maneuvering the part in to place.


If either or both surface is less than fair, a liberal application on both surfaces.


In at least two cases. RTV only, no gasket.


A. My IHC Scout II. A weird stacking of outlet parts that defied the proper alignment of a gasket in the assembly process.


B. The Ram Horn after market exhaust manifolds on the LT1 in my Jaguar. High temp O2 sensor safe RTV. Done circa 2004. Still just fine.


Carl

 

Greg my friend

All studs and co have been long removed and are all bought new. The tip with the loctite is a good'en. I'll treat the studs and screws with that stuff.

Though I wonder how the screws can come undone!? But after going into my manual, it is no wonder, as the are no torque specs...

Cheers

Damien

 

I was wondering the same thing. Can't say I've ever had it happen on any water pump job I've done, including Jags.

Torque spec on a water pump fastener? it's just something you develop a feel for . After running the fasteners in as far as you can with just finger strength on your wrench, give 'em each one additional small grunt...a quarter turn or so. They're small fasteners; 15-20 ft-lbs would be my guess


Cheers
DD

 

The screws are quite beefy... Compared to the tiny screws on the AJV8 cross pipe out of plastic, which get a good bit of grunt, I can imagine these screws easily taking something like 60 nm... Apart from the one cross headed screw on the bottom right of the pump... Allen or torx would have been a better choice there in my opinion...

 

Yes that large coutersunk Pozzi was a real PITA.

I did not use a gasket just RTV and my pump has been good for 6 years now no leaks.

 

Hmm, now I'm stuck between two ways... Pure RTV instead of a gasket or a gasket with a small smear of RTV on the contact areas...

 

One of Jaguar nastier pranks. Nearly as bad as inline fuses scattered throughout the car, hither and thither

I wonder how many first-timers have been flummoxed by that screw....hidden out of easy sight?



If the mating surfaces are really pristine I'll go without any sealers. Usually, though, I find some little defect that justifies use of some sort of goop. Permatex #2 has been my regular 'go to' product for years.

Cheers
DD

 

Considering the amount of labor involved if the decision ends up being wrong this is one time (OK, there are others!) where I'd be cowardly and go with a gasket and a smear.

Cheers
DD

 

I've been thinking about this all day. And I think I'll gomsafe by fitting the gasket and a smear of RTV. JUST to make sure I don't have anything to worry about later

 

Yeah, that screw was a shock, cos mine was missing as I removed my pump... It had been replaced with a ground-off normal screw/bolt... So I got a new one... With all other screws and co

 

Agree, veer to the safe side. And, If it were me as to the shrouded Pozi ? Bye bye, hello Allen. I just like 'em. So positive.


Carl

 

Allen would be best but I haven't seen tapered allens yet...

There are so many choices Jaguar could have made better

 

No sooner said than done Daim:
Socket Countersunk Head Screws M3 up to M24 A4 [Din 7991] : Avon Stainless Fasteners website


These people do European delivery no problem
UNC
Countersunk Head Hex Socket Screws (82° countersink UNC : A2 Stainless Steel , Fixings specialist UNC


Metric
Hex Socket Screws A2 Stainless Steel : Countersunk Hex Socket Head , Fixings specialist A2 Stainless Steel


Greg

 

Cheers Greg! Too late though... Am keeping the normal screw