Head Gasket Precautions

[fastrack1966]

OK I have to give up, the KSeal did part of the job, the “Rock ‘n roll” on starting the engine is not as bad but I am losing litres of water every 40-50 miles. It’s not wet on the ground, and the white smoke is slight, but I think head gasket it has to be. As anyone who recalls the dreaded Diesel Head Woes spring 2004 will guess, if this has gone again after about 7-10,000 miles then what did I overlook? (Turbo Diesel 2 Litres)

1) Head bolts. Yes I reused them but I measured “a couple” and they were within the limits. If I restart this job I’ll spare no expense on bolts, are Rover the best quality?
2) Gasket Set: Used a set by FAI. May not be the best? Can anyone suggest the ultimate hi-grade head gasket makers please? Does it matter? Only when I rang the head skimmer yesterday did he mention thicker gaskets. I assume if I have a second skim I’ll need one.
3) Skimming - .010 inches was skimmed in 2004. Only just now I’ve checked my Rover manual and it says “Max reface .008 inches”. Does this mean the skimmer fouled up? Surely I should have used a thicker gasket if he is going anywhere near the max reface? If he has gone beyond it is the head knackered?
4) Torque settings: It’s a long time since I’ve changed a petrol HGask but I recall having to re-torque them after a few hundred miles. Does this not apply to diesels?

Due to other commitments I’ll not be starting this little job for weeks!
BJ

[B18 GPC]

OK I have to give up, the KSeal did part of the job, the “Rock ‘n roll” on starting the engine is not as bad but I am losing litres of water every 40-50 miles. It’s not wet on the ground, and the white smoke is slight, but I think head gasket it has to be. As anyone who recalls the dreaded Diesel Head Woes spring 2004 will guess, if this has gone again after about 7-10,000 miles then what did I overlook? (Turbo Diesel 2 Litres)

1) Head bolts. Yes I reused them but I measured “a couple” and they were within the limits. If I restart this job I’ll spare no expense on bolts, are Rover the best quality?
2) Gasket Set: Used a set by FAI. May not be the best? Can anyone suggest the ultimate hi-grade head gasket makers please? Does it matter? Only when I rang the head skimmer yesterday did he mention thicker gaskets. I assume if I have a second skim I’ll need one.
3) Skimming - .010 inches was skimmed in 2004. Only just now I’ve checked my Rover manual and it says “Max reface .008 inches”. Does this mean the skimmer fouled up? Surely I should have used a thicker gasket if he is going anywhere near the max reface? If he has gone beyond it is the head knackered?
4) Torque settings: It’s a long time since I’ve changed a petrol HGask but I recall having to re-torque them after a few hundred miles. Does this not apply to diesels?

Due to other commitments I’ll not be starting this little job for weeks!
BJ

Hey there ;

1 ; Payden head Bolts are very good!
2 ; With the payden gasket set aswell - part of the kit possibly..
3 ; i wouldnt worry one bit.
4 ; i wouldnt have thaught so..

[Diesel Phil]

Right, i hope you don't laugh me out of town, but could it be the fan is not coming on and so the water is overheating and escaping the rad cap pressure valve?

[B18 GPC]

rad cap pressure valve?


The Who ?

Sounds Erm.. Good though :confused:

[Diesel Phil]

The Who ?

Sounds Erm.. Good though :confused:
If the radiator fan does not come on, due to corrosion of the contacts of the thermostatic switch usually, then overheating will occur. Normally though this will cause some water to escape through the radiator cap which has a pressure valve built in. That carries out some heat with it, and as you drive along the radiator cools due to the rush of air. So long as you keep the water topped up and don't get stuck in traffic it doesn't go bang, it just evaporates off about 1 litre of water every 100 miles.

[e692wtt]

Expansion tank cap weak? Doubt it - the engines don't run especially hot, and the fan rarely comes on even in slow traffic on hot days.

On the Monty TD I drove on Staples2Naples last year, the heater worked fine but the temperature gauge rarely got over 1/4 of the way up the gauge (even flat out on the Autobahn) until the car got some serious stick up the Alpine Passes. The gauge then reached nearly half way... Having said all this, the expansion tank cap on that car didn't hold pressure at all and we only lost probably 2 litres of water in 3,500 miles of pretty hard driving.

I think the problem is more fundamental - maybe something as simple as a loose or split coolant hose.

Do the hoses go hard within a minute of starting from cold? This would indicate head gasket problems. Ditto if the heater has stopped working - the gases venting into the cooling system from the engine head uphill - and first stop is usually the hoses to the heater. If both of these tests are negative (that is, the heater works fine and the hoses don't harden pretty quickly) then the problem is elsewhere.

Another way to diagnose head gasket problems is to go to your local MoT station and ask them to 'sniff' the gases in the expansion tank (don't put the probe in the coolant) - hydrocarbons would indicate problems.

Hope this helps and reassures :) .

[Diesel Phil]

Hmmm.

Well, mine used to lose loads of water from the radiator cap (as i still call it from Mini days) until getting the fan switch right.
And it used to run cold too, but having swapped the thermostat it gets to normal in about 3 - 5 minutes. It uses less fuel at normal temp too (about 20-30 extra miles from a tank).
Swapping the thermostat increased the water loss, because that was done before the fan switch.

Mine does still get warm in traffic though, and uses water and oil.

Next time i change the oil i will use engine flush because I only filled it with about half the specified amount!

It still runs fantastically well though!

[fastrack1966]

Thanks everyone:
Water is bubbling at the expansion tank with cap off within a minute of starting.
Heater has been very iffy for months now, usually cold
No evidence that water is escaping around the rad cap
Just to confuse things the last time I checked the hoses were not hard.
Will try the gas test and the fan test next time a drive it warm enough, a day or two.

[e692wtt]

Hmmm.

Well, mine used to lose loads of water from the radiator cap (as i still call it from Mini days) until getting the fan switch right.
And it used to run cold too, but having swapped the thermostat it gets to normal in about 3 - 5 minutes. It uses less fuel at normal temp too (about 20-30 extra miles from a tank).
Swapping the thermostat increased the water loss, because that was done before the fan switch.

Mine does still get warm in traffic though, and uses water and oil.

Next time i change the oil i will use engine flush because I only filled it with about half the specified amount!

It still runs fantastically well though!

D'oh! :) 'Jonah' had a good secondhand head fitted, as well as a seemingly new radiator of unknown source (not a Montego one - it was free floating!!!) that was certainly thicker than the one that came off, before we went to Naples - and then had no cooling system problems at all. He came to us with a blown headgasket and a cylinder head with a face resembling swiss cheese, so he didn't behave very well before the new head :laugh: .

He had 152,000 miles on the clock at the time of the new head, 154,000 when leaving for Naples and 157,500 8 days later - and used a litre of 10w/40 (and the same amount of coolant) every 2,000 miles. I think that's pretty OK for a car that cost £60 :thumbup: . A little tlc would have cured the loss of coolant, and thicker oil would have reduced the oil consumption. I miss that car... :o

Oh, and I call it the 'radiator cap' too...

[fastrack1966]

Well I stuck my kneck out and went for another round-town drive:
1) After a mile I removed the rad cap and lost a pint of water into the air, stone cold of course.
2) After a few miles the temp gauge was about midway and the fan was still. When does the fan operate? I am reluctant to go out of town for a half hour run for obvious reasons.
3) Hoses do not seem "very hard", still squeezy.
Will ring around to try and get a gas test on the expansion tank. When I bought my gasket set two years ago why don't the shop ask "What thickness?". If the head is over-skimmed or even properly skimmed surely I needed a thicker gasket?
BrianJ

[G Force]

Hi Brian, just read this thread and this is what I think.

The head gasket has definitly failed or the head is cracked. Which ever the problem the head needs to come back off.

The machine shop should really of observed the max tolerance for skimming but if your figures are accurate then the 2 thou overskim is not the end of the world unless the head had been skimmed previously. If I remember correctly the main problem with over skimming above the tolerance, was that the purpose for the valve reccess shaped in the head would be negated and a detrimental condition called pocketing around the valves would exist, If I was faced with the decission on my own car of scrapping the head or a 2 thou overskim I would risk it. Over skimming by a large amount (as in if the head had been skimmed previously) would lead to the head being scrap.

Once the head is off I would carefully examine the gasket to see where or not the problem is, measure the head thickness between the head surface and lower cam journal and compare it with the new head thickeness to see how much is skimmed 0ff. If it is only 2 thou then get the head crack & pressure tested to see if it is Ok. Anything over get a 2nd hand head.

Once you have a servicable head I would use a new rover gasket. Make sure both head & block surfaces are clean & true.

Clean all block head bolt thread holes of oil & coolant. Check the head bolts again for stretching & necking. I would torque the bolts with the strain guage type torque wrench as it is too easy for some mechanics to overtorque with the click type wrench.

There are no thicker gaskets available because they are not neccessary when all specifications are considered.

The engine cooling fan only comes on when the radiator temp rises too high this usually corresponds with the temp guage needle nearly touching red.

Best regards gary :)

[talkingcars]

When we got our TD maestro it never got warm so I replaced the thermostat which cured that problem, now the gauge sits at about 1/4.

If I cane it (90mph+ where permited) she blows through the rad cap (sorry, I am that old) but otherwise uses no water.

The interior heater matrix will blow cold when the water is low in the system, regardless of why the water is low, it is not a gauranteed sign of head gasket problems.

To check the rad fan 1) short the contacts on the sensor on the radiator to each other or 2) leave the car ticking over, after 30 minutes it should have come on or 3) leave the car ticking over from cold with the cap off, measure the temp in the tank, once it reaches over 95' the fan should be on as the fan sensor is set for either 88 or 92' IIRC.

[MaestroTurbo]

When we got our TD maestro it never got warm so I replaced the thermostat which cured that problem, now the gauge sits at about 1/4.

If I cane it (90mph+ where permited) she blows through the rad cap (sorry, I am that old) but otherwise uses no water.

The interior heater matrix will blow cold when the water is low in the system, regardless of why the water is low, it is not a gauranteed sign of head gasket problems.

To check the rad fan 1) short the contacts on the sensor on the radiator to each other or 2) leave the car ticking over, after 30 minutes it should have come on or 3) leave the car ticking over from cold with the cap off, measure the temp in the tank, once it reaches over 95' the fan should be on as the fan sensor is set for either 88 or 92' IIRC.

You are also showing signs of HGF (never getting warm except when flat out, cold heater and blowing water out)

[talkingcars]

You are also showing signs of HGF (never getting warm except when flat out, cold heater and blowing water out)

I cured the "never getting warm, cold heater" problems by replacing the non closing thermostat.

It only blows water out when hammering it which I tend not to do (like I said, I am getting old), there is no mayo in the oil, no oil the water, uses no more oil than any other diesel...........

[e692wtt]

...

It only blows water out when hammering it...

It's not meant to do that :) . 'Jonah' our Staples2Naples TD Estate showed readings of half on his temperature gauge when flogged up mile-long steep climbs in the Alpine Passes - and that's a lot harder than running fast on the motorway - and flat out on the Autobahn didn't make the temperature gauge needle move upwards from around 1/4 of the way across at all. In all this flogging he lost around a litre of water in 1000 miles due to the system not holding pressure (no mixing of fluids, heater worked fine even though the coolant tank was empty, no pressurisation of the cooling system and so on). Edit: the engine showed no signs of blowing water out from the radiator cap, to clarify that.

Unless it is boiling up due to the radiator being partially blocked, there's a problem somewhere - and I'd also say 'head gasket issues'.

[fastrack1966]

Thanks Gary, that seems to be the definitive reply, and I'm waiting to see what the AA Technical have to say. One of my mechanics said its not worth keeping risky bolts, and I've found a set for £25 whenever I start,

BrianJ

[fastrack1966]

Well here's another thorough set of instructions for what not to do if I try and rectify what I did! Courtesy AA Technical:

"In respect of the head bolts, the workshop manual says (in the overhaul and
refit section): 'Check the cylinder head bolts for distortion. Use a
straight edge and renew any bolt showing a reduction in diameter of that
part of the thread that has not been in engagement with the block.'

Manufacturers either recommend a maximum amount which can be removed from the head or say that it must not be refaced. In the case of this particular engine, the original depth is 120.1 to 120.0 mm (4.728 to 4.724 in). The maximum permissible bow in the head is 0.1mm (0.004in). The maximum amount which can be removed during refacing is 0.2 mm (0.008 inches). Use of a thicker gasket to replace lost metal is not really acceptable and it might be necessary to obtain a replacement head.

Years ago the majority of cars had to have the head retightened after about
500 miles, but this no longer applies."

How on earth do we measure the bow in a head if the limit is a tenth of a mill?

BrianJ

[G Force]

How on earth do we measure the bow in a head if the limit is a tenth of a mill?

BrianJ

Hi Brian you need a precision engineers straight edge and a set of feeler gauges. You lay the staight edge length ways, width ways across several portions of the head surface, and diagonaly length ways in two directions, all the time checking if you can insert the 0.004in feeler gauge. if you can get the feeler gauge under the straight edge anywhere then the head is scrap.

Gary

[fastrack1966]

Thanks Gary, sounds like something I'll leave to the guy who is skimming it, again, if he does skim it

BrianJ

[darren74]

:laugh: i dont no anything aboute car engine,s but i just thought i would add to this thread and say hello :laugh: :laugh: :driver:

[exminiman]

i`m doing a head gasket in a few weeks....do i absolutely need new head bolts or can i re use the old ones?