XK engine in a Mk V


I have been offered a MkV without the original engine. The seller says I can fit an XK engine into it and is supplying one. In principal I do not object. Tim, Peter and Pekka think its not a good idea and worse, it seems it would require far more modification than just new engine mounts, including cutting into the bulkhead and lengthening the bonnet. I’m OK with new engine mounts, but not the rest.

The seller is very insistent that he has done it before, without major mods apart from engine mounting points and has sent me a snapshot showing the car from his photo album. He says it does require an ‘electric ventilator’ to be added. I have no idea what he means but have asked for clarification.

Could I get some comments please on the photos the seller has sent me? I am not sure who is correct any more! I am not a purist, so am not against some mods, but I draw the line at cutting bulkheads and extending the radiator.

Finally, can anybody give me an idea of how easy/difficult it would be to source the correct motor and gearbox if I went that route, and approx idea of what I might expect to pay?

Thank you all for your help. Squibble


Sorry, wrong title. I mean an XK engine.

(Jag-ur) #3

Ask Cordell Newby he knows his MkVs well… and MAY have a spare engine.

(Rob Reilly) #4

I certainly would NOT do it. Or the price would have to be VERY low and the condition otherwise to be VERY good before I would.
The XK engine is too long for the Mark V engine bay. People did this swap when good carburetor XK engines were cheap and plentiful and the cars with blown engines were cheap.
To fit it in you must cut away part of the front frame cross member to give clearance for the crankshaft damper. Be sure the oil filter is not too long and has enough clearance over the right hand torsion bar. Also remove the tachometer drive shaft and substitute another blanking plate like the one on the other camshaft, so you would have no working tachometer. You have to remove the fan and substitute an electric fan. You have to rework the radiator ports because they are the wrong size. You would need a bell housing and starter motor from an XK engined model, assuming you want to use the original JH or SH type gearbox. You would have to fabricate front engine mounts, throttle linkage and exhaust.
These days a swap to a Chevy 350 and automatic would make more economic sense and you’d have your basic street rod, though that’s still no good for me.
You are much better off to try to find a restoration candidate Mark V engine or buy a car with an original type engine.
There ought to be some in England.
A large stash of Mark V engines and other parts was found in Australia not too long ago. Maybe they could be tracked down.

(- 1950 MkV, 1959 XK150,) #5

I suspect he means an electric push fan on the radiator, as to shoe-horn the XK engine in, the water-pump mounted fan would be removed.

(Ed Nantes) #6

And also consider that the diff ratio that was suitable for a puhrod engine of 125hp is not going to be that pleasant with 160 = HP so that would need altering.
I also think that any second hand 70 yo engine would be unlikely to be in serviceable condition without needing work done.
Perhaps one needs to work backwards from, How much are you planning to have spent by the time it is on the road? Then deduct REALISTIC amounts to cover mechanical and body work. Bear in mind a full paint job these days runs to AU$ 15 -20,000.+


Hello Rob, many thanks for your timely and considered advice! With so much advice on the forum not to proceed, I would be silly to go ahead. There are just too many modifications which I don’t want to do and which would adversely affect the final value of the car. I have decided I will not buy this car.

(Timothy M Fox) #8

Ask the dealer to give you a firm quote on the fitting of the XK engine, then get him to do it telling him you will pay him the quoted amount when the work is complete. That will test his voracity, not to mention competancy! :wink:

Buy a well sorted, original MKV from a Jag Club member in Europe and just enjoy driving it!