Head Gasket

[JOHN'S TR6]

I took the TR6 to work this morning for the first time this year, giving it a good thrashing as many TR Register members suggest once in a while.

 

Having cleaned the externals of the engine over winter it became apparent that my head gasket is leaking oil with staining covering the dizzy pedestal and surrounding area.

May this moderate leak affect smooth running under 1900rpm?

 

I am moderately mechanically minded having done many jobs on the car, but I am a little more reluctant to take the head off.

 

If I did the job myself, would you suggest I have the head skimmed as a matter of precaution and is the job relatively straight forward for some one of Limited mechanical awareness of the internals of the engine? Bolt on bits, clutch and ring gear no problem .

 

In a way I would love to do the job myself as this is part of owning an old car I feel.

Oh yes, and the cost.

 

If I did go down the route of getting a proffessional to do it, has any one got any ideas as to a ball park figure to change the gasket and skim?

 

John

Edited May 12, 2008 by JOHN'S TR6

[charlie74]

before you go that far, just remove the valve cover and rocker pedestals and check the torque on the head bolts.

do you see any coolant in the oil when you check it? if not, a retorque might be sufficient.

c74

[JOHN'S TR6]

A retorque might be sufficient.

 

 

Charlie

 

Actually, thats a brilliant idea.

 

Thanks John

[Richard Crawley]

A retorque might be sufficient.

 

 

Charlie

 

Actually, thats a brilliant idea.

 

Thanks John

Always a good idea; it may fix the oil leak but I doubt it’s the cause of your fluffing problem under 1900 RPM!

[88V8]

Take a gander at this:

 

http://www.tr-register.co.uk/forums/index....amp;hl=pedestal

 

I wouldn't skim the head to cure what I guess is a trivial leak. Even supposing it does cure it, which is by no means certain, raising the CR is undesirable.

Regard it as localised rust prevention.

 

Ivor

[JOHN'S TR6]

Ivor

 

Thanks for that link. That was very interesting.

I will check the torque as charlie suggested but after reading the link, I am now half tempted to leave the head alone.

 

The oil pressure on normal temperature at tick over can be as low as 2 kg/cm2 but shoots up to 5 when revved.

 

Is that sort of low pressure on hot tick over normal? 10/40 oil

 

John

Edited May 13, 2008 by JOHN'S TR6

[Richard Crawley]

Ivor

 

Thanks for that link. That was very interesting.

I will check the torque as charlie suggested but after reading the link, I am now half tempted to leave the head alone.

 

The oil pressure on normal temperature at tick over can be as low as 2 kg/cm2 but shoots up to 5 when revved.

 

Is that sort of low pressure on hot tick over normal? 10/40 oil

 

John

I would advise you only use a good quality 20w/50; 10w/40 is designed for use in modern engines which run much tighter & improved machining tolerances; this can be the major cause of low oil pressure when used in older engines, they just aren’t designed for it. To save me working it out, what’s 2 kg/cm2 in old money?

[JOHN'S TR6]

To save me working it out, what’s 2 kg/cm2 in old money?

 

 

Richard,

Thanks for the oil information. Looking at the gauge 2kg/cm2 seems to be about

30-35 lb/sq"

 

John

Edited May 13, 2008 by JOHN'S TR6

[Richard Crawley]

To save me working it out, what’s 2 kg/cm2 in old money?

 

 

Richard,

Thanks for the oil information. Looking at the guage 2kg/cm2 seems to be about

30-35 lb/sq"

 

John

Looked it up; 1kg/cm2 = 14.22 lb/in2. Based on that, your pressures are 28.44 lb/in2 & 71 lb/in2. The tick over pressure is a little lower than I would like but using a decent 20w/50 would almost certainly increase it. 70 lb/in2 is very good for a hot engine; in fact I’m a little surprised you can achieve those sort of pressures with a 10w/40 oil, have you tweaked anything?

[IanR]

Hi Folks,

 

Not sure if I posted this already so apologies if I have.

 

Since this thread is exactly the same faut as I reported a while back in "an annoying little oil leak" and also referred to above, I thought I tell you that I did in fact remove the head and fitted a new head gasket, but this time with a good but carefully applied covering of Wellseal. Result... well there is good news and bad news. The good news is the oil leak has totally stopped. The bad new is the the core plug between coil and alternator, which was NOT leaking befoe I took the head off, has now started to leak a little. Buggar!!

Since I have filled up with 4life coolant and also removed the troublesome block tap does anyone know of a coolant additive that does not clog up the rad but stops minor leaks to avaoid draining down yet again

 

Overall I think I should have left it alone but I like things NOT to leak

 

Cheers

[88V8]

does anyone know of a coolant additive that does not clog up the rad but stops minor leaks to avaoid draining down yet again

 

Kalimex K-Seal, your local shop, pour and forget.

 

You will find a multiplicity of 'cures' in the shop, that's what a generation of wet-liner engines does for the market, but eschew all other brands.

 

Cured the six leaking core plugs on my V8 that wept about 1 pint every 200 miles, fixed the blowing headgasket on my 205 GTI, pour and forget.

 

Also available on-line.

 

Ivor

[IanR]

Kalimex K-Seal, your local shop, pour and forget.

 

You will find a multiplicity of 'cures' in the shop, that's what a generation of wet-liner engines does for the market, but eschew all other brands.

 

Cured the six leaking core plugs on my V8 that wept about 1 pint every 200 miles, fixed the blowing headgasket on my 205 GTI, pour and forget.

 

Also available on-line.

 

Ivor

 

Thanks Ivor ill see if I can get some and give it a try

 

Cheers

[JOHN'S TR6]

Richard

 

I think I was talking rubbish earlier today with the oil pressure. (My boss was on the prowl)

On giving it a better look on the way home, the hot pressure on tick over was approx 34 lbs sq"

On Hot while running about 50 lbs sq" . Under load it crept up a tad about 55.

 

The 70lbs is while cold.

Do you think that the 10/40 is going too thin when hot?

What make should I look out for on the 20/50?

 

The car felt dreadful on the way home yesterday. It coughed and spluttered. I felt a bit depressed by the time I got home.

Today it was a dream, plenty of go, a bit smoother lower down the rev range. Normally a bitch under 1900rpm.

The thing is, with my TR6, you never know what mood the car is going to be in.

 

John

[dykins]

Richard

 

The thing is, with my TR6, you never know what mood the car is going to be in.

 

John

 

 

...just like a woman

 

..everyday an unpredictable adventure

 

Regards

 

Peter

[Richard Crawley]

Richard

 

I think I was talking rubbish earlier today with the oil pressure. (My boss was on the prowl)

On giving it a better look on the way home, the hot pressure on tick over was approx 34 lbs sq"

On Hot while running about 50 lbs sq" . Under load it crept up a tad about 55.

 

The 70lbs is while cold.

Do you think that the 10/40 is going too thin when hot?

What make should I look out for on the 20/50?

 

The car felt dreadful on the way home yesterday. It coughed and spluttered. I felt a bit depressed by the time I got home.

Today it was a dream, plenty of go, a bit smoother lower down the rev range. Normally a bitch under 1900rpm.

The thing is, with my TR6, you never know what mood the car is going to be in.

 

John

70 when cold is fine but it’s dropping a bit low when hot & I would advise changing to a 20w/50 oil; I’m using Millers at the moment but Penright also has a good reputation; years ago I used nothing but Duckhams in all my engines but I’ve been told it’s not the oil it once was.