It's done it again

(Graham Jordan) #1

My Mark V has continued to smoke from the exhaust since having the engine rebuilt (badly by an engine reconditioning company). I decided to try some valve stem seals without removal of the head, a modification done by the local early Jaguar club here, but when I pressurised # 1 cylinder with 80 psi to hold the valve closed air came out of # 2. I tried compressing # 3 which also came out # 2.
I have since removed the head expecting to see a blown head gasket but there is no evidence of such?
Both the head and block were machine faced. I took great care in confirming none of the acorn head nuts were bottoming out and that the head gasket was correctly fitted. Tried two different torque wrenches to confirm setting. No cracks I can see. Whats left?
I will post some photos shortly.
Graham.

(Graham Jordan) #2

(Graham Jordan) #3

(Peter Scott) #4

Hi Graham,

If your valves are not well ground in then air pressure will not hold them in place with no spring present and it’s quite possible for the air to find its way into another cylinder.

With all the valve springs and spark plugs in place and the head inverted and level fill each of the combustion chambers with paraffin. If any chamber leaks before the others then suspect its valves need reground.

HTH

Peter

(Rob Reilly) #5

Just to be clear to everyone, paraffin in Britain means lamp fuel, i.e. kerosene, where in the USA paraffin means candle wax.

Are we seeing the head gasket separated, part stuck to the head and part to the block? I have never used that type of head gasket except on lawn mowers. Does anyone want to comment on the use of this gasket?
Here is what I have.

(Ed Nantes) #6

The type of Gasket Rob has is the ideal type. But Not readily availble to my knowledge. The one Graham has , I can’t positively identify now , but maybe a batch the Qland club had done.
WE find that now engines have been rebuilt with all sort s of pistons sometime in large oversizes that for these gaskets need t be made for oversize bores. And in the past the bores have sometimes been "moved’ RE-bored slightly off centre to allow for the wear being greater on one side.
I would have thought that valve seals if t was smoking mean attacking the symptom rather than the cause.
These days K line inserts in the stems give a tighter tolerance the valve stem. IF installed correctly. Not always a given.

(Graham Jordan) #7

Yes I can thank my engine rebuilders for the smoking. The seals were a stop gap method to save some embarrassment while driving and to confirm it wasn’t something like a broken ring.
Gasket was from the Qld jag club. That is the third one fitted post rebuild.
First time new pistons seized
Second time water came out the carbs as reconditioned forgot to torque the head down.
This is the third that I painstakingly fitted.
Next is # 4

(Graham Jordan) #8

Something of interest I just found.
An original head gasket set from the major Jaguar dealer Brysons in Australia.
Regards, Graham.

(Peter Scott) #9

That’s certainly a good Corrujoint gasket with the outer rim embossing too but I suspect the modern Aus gaskets you have been using are at least as good.

Peter

(Peter Scott) #10

Actually I take that back. I see there doesn’t appear to be any sealing around the water ports in the modern gasket so I would imagine it could easily leak into the push rod passages/sump or out the sides of the engine.

I think it’s true to say that the studs on the push rod side pass through the internal inlet manifold so you may have been drawing coolant into the cylinders. Are you sure the exhaust smoke was not steam?

The lack of sealing around those inlet side studs will have also permitted the engine to suck oil from the push rod holes so possibly you have a mix of oil and water vapour in your exhausts…

Peter

(Ed Nantes) #11

What next , first electric jaguars ,now steam powered.
The modern Aust gaskets[ not the Q land club ones which I thought were sourced from NZ are available with or without the extra crush rings for the water ways. We have used a lot of them without the extra crushes without problems. But they can be ordered for an extra cost.
I thought the original Factory corrajoint gaskets were steel not copper.
The cooper ones from Brysons might have been made by Farrahs in Fitzroy years ago. Unfortunately the corrajoint type needs[ expensive] tooling to press
Checking against another { uncalibrated] tension wrench is no guarantee. I recall someone complaining a head gasket didn’t seal properly even after check with a friends tension wrench as well. He later confided that both wrenches turned out to be inaccurate when he later sourced a better quality one. In aviation tension wrenches are required to be re-calibrated and certified annually. And Hylomar in a sample of professional mechanics tension wrenches found about half to to be inaccurate.
I also remember the day a newly restored SS100 was imported and taken out of the container, with coolant running out of the carbies. Turned out that recoils had been used in the deck , but left sitting proud of the surface. So the head gasket couldn’t crush.

(Peter Scott) #12

Hi Ed,

Well I must admit that all the Corrujoint gaskets I have come across have been copper and not steel. Are you sure you are not getting confused with the steel compression plates that were fitted post war to cope with low octane fuel? (They were sandwiched between two Corrujoints.)

Corrujoint
Note the spelling of Corrujoint too.

I also admit that I have no experience of the type of gasket shown in Graham’s first photo but it looks to me as if the pimpled areas could easily communicate in the absence of the crushes.

Peter

(Ed Nantes) #13

Sorry sir on my spelling of Corrujoint. [ The dog ate my homework, so not my fault]
But I have seen a few Corrujoint made in steel [ and in UK no less.
WE are still faced with the issue that making them would require a press tool[ or more if one considers1 1/2 ,2 1/2 and 3 1/2 litre versions

(Peter Scott) #14

Are these dimpled things made of Klingerite? I thought that Klingerite presented a smooth surface.

Peter

(Graham Jordan) #15

I filled the combustion chamber as Peter suggested but used oil. Yesterday I see it has crept into # 2 chamber so it wont surprise me if the head is cracked.
I’ll be taking it this week to the company that has just finished the machine work on my SS engine for inspection.
I have a selection of head gaskets so will post a photo of these later
Will let the forum know the findings.
BTW The valve stem seal fitment requires the collets to be machined slightly shorter to allow Holden (Australian car company) valve stem seals to be fitted just below the collets.

(- 1950 MkV, 1959 XK150,) #16

Hi Graham,

I hope that you find that your head is OK, however if not; this may be of help… Ebay Mk V engine parts

(Ed Nantes) #17

I suspect the pic indicates there are a number of ex wedding car MK Vs going round with Holden 202 engines and Trimatics.

(Rob Reilly) #18

This seller is in Sydney and has a bunch of listings for accumulated Mark V parts, doors, chrome, wings, etc.

I would be curious to know the reason for cutting rectangular holes in the bonnet side panels? Adding some sort of turn signals?

If anyone in the NSW area gets all this stuff, I hope they will pass along their contact info.

(Roger Payne) #19

I suspect its the same guy I visited just on two years ago.
Ran a wedding car business of maybe 20 classic cars, including at least three Mark V (maybe more); two DHC, and one a STRETCH Mark V SALOON limousine. Had an industrial premises near Sydney Airport, but was winding everything down to retire. But lots a Mark V parts, all pretty genuine mechanical, electrical and panels, that he had accumulated over 30-40 years, thus I guess the ‘must sell’.

(Rob Reilly) #20

You mean this one? I didn’t get the chassis number.