Technical Head gasket?

[tobywood13]

Hi all, I have a feeling that my head gasket has just blown. Car suddenly got very hot, I pulled over and saw that some brown water had sprayed around the vicinity of the radiator cap. The rad is empty, with brown sludge on the cap. Can’t see a sign of a leak anywhere else.

I’ve recently replaced all hoses, radiator, water pump, and thermostat to address a constant loss of water, and since the pump (last thing I did) it’s functioned fine without any obvious leaks. This happened at 60mph with no signs of overheating. Coolant was changed recently.

It has been taking slightly longer to start recently, just a few seconds, so may have been leaking coolant into the cylinders. Is this likely a head gasket?

I can’t see any mayo on the dipstick or the oil cap, just this sludge in the radiator.

I’m stood next to it waiting for assistance, and can hear a glug coming from the radiator every few seconds.

 

[bugsymike]

Hi all, I have a feeling that my head gasket has just blown. Car suddenly got very hot, I pulled over and saw that some brown water had sprayed around the vicinity of the radiator cap. The rad is empty, with brown sludge on the cap. Can’t see a sign of a leak anywhere else.

I’ve recently replaced all hoses, radiator, water pump, and thermostat to address a constant loss of water, and since the pump (last thing I did) it’s functioned fine without any obvious leaks. This happened at 60mph with no signs of overheating. Coolant was changed recently.

It has been taking slightly longer to start recently, just a few seconds, so may have been leaking coolant into the cylinders. Is this likely a head gasket?

I can’t see any mayo on the dipstick or the oil cap, just this sludge in the radiator.

I’m stood next to it waiting for assistance, and can hear a glug coming from the radiator every few seconds.

Does sound like it.
Has any rad seal type additive been used?
When coolant changed was all air bled from system?
If the brown sludge is not additive then it could be a long time build up of muck that was blocking the radiator and now has cooked the head gasket.

 

[tobywood13]

Does sound like it.
Has any rad seal type additive been used?
When coolant changed was all air bled from system?
If the brown sludge is not additive then it could be a long time build up of muck that was blocking the radiator and now has cooked the head gasket.

No rad sealant used. Bled it all through when I changed coolant and checked it regularly over the following days to ensure it was fully topped off. Radiator is brand new, as is water pump, hoses, thermostat, so not likely to be old sludge. I’ve been driving it everyday for a few weeks since changing the rad with no issues, including a 7 hour trip each way to Devon.

 

[bugsymike]

There doesn't need to be "mayo" on dipstick or in oil cap for head gasket issue.
If coolant has been going down for some time hence the need for all the parts you have changed , there is a very good chance at some point the coolant was so low it couldn't circulate around the engine, at that point it will rapidly overheat and blow the gasket/warp the cylinder head etc.
There are several tests that can be done to show a faulty head gasket issue, from filling the coolant to the brim starting the engine holding revs around 2000 then letting it idle and checking for gas bubbles coming up sometimes smelling of combustion, another test is a tool that sniffs that gas and changes the colour of chrystals due to combustion gas present, another test is a leak test done with more garage equipment which takes longer but is more comprehensive and can show which cylinder the fault lies in etc.
After over fifty years in the motortrade I have used all those methods, the leak test being the most accurate capable of showing even a very slow leak from gasket.

 

[tobywood13]

Topped it up from a nice elderly lady’s watering can, limped it the last couple of miles home. Definitely the head gasket, the exhaust gas is venting into the cooling system and pressurising it well over what it should be, as soon as I took the rad cap off it squirted all over the place and smoke/steam was coming out, but not normal coolant steam. It started misfiring at idle too, so I think coolant is getting into at least one cylinder.

New head gasket, bolts, oil, coolant needed.
Has anyone got a link to a parts list and good guide on how to get the head off? This will be my first head gasket, but it’s a pretty simple car to learn on. Also, if anyone on here is in East Anglia, any recommendations on somewhere to get my head skimmed?

 

[tobywood13]

I’ve looked on Ricambio, all the gasket kits seem to say ‘up to 1992’. My car is a 1993, with the SPI. Will these earlier kits fit my car?

I’m not worried about all the seals it comes with, just the head gasket, intake, and exhaust manifold ones. I’m hoping that they say ‘up to 1992’ due to one of the ones I don’t need to use.

 

[Pugglt Auld Jock]

I’ve looked on Ricambio, all the gasket kits seem to say ‘up to 1992’. My car is a 1993, with the SPI. Will these earlier kits fit my car?

I’m not worried about all the seals it comes with, just the head gasket, intake, and exhaust manifold ones. I’m hoping that they say ‘up to 1992’ due to one of the ones I don’t need to use.

At the risk of boring everyone. My go to for stuff like this is Shop4parts: https://www.shop4parts.co.uk/?gad_s...G0BEbyFY2VekrV3LNDnDk3KvATeegFM8aAs_LEALw_wcB They are very approachable and knowledgeable and won't mind at all if you ring them up asking for advice. Have VIN/chassis number/reg no ready to hand.

 

[jalopear]

Seguro junta quemada, desarmar y cambiar lo necesario.

 

[tobywood13]

I think I've found the correct head gasket and head bolts after using ePER.
Aside from finding somewhere near me who can skim the head, is there anything else I should order to replace at the same time?

 

[bugsymike]

I think I've found the correct head gasket and head bolts after using ePER.
Aside from finding somewhere near me who can skim the head, is there anything else I should order to replace at the same time?

Using a steel straight edge and 2 thousands of an inch feeler gauge check cylinder block for flatness after cleaning it.
It will be also interesting to see how distorted the cylinder head is using the same method before having it machined flat again.
Apart from that check or replace any damaged seals or gaskets when disturbed.
By the way are you 100% sure the intial cause of the head gasket failure has been rectified?
If you need cylinder head torque settings I may be able to supply details if you let me know the Engine Series number from your chassis/vin plate.
Trust you have a good accurate torque wrench as a Forum Member recently snapped several bolts due to a dodgy torque wrench.

 

[Pugglt Auld Jock]

Using a steel straight edge and 2 thousands of an inch feeler gauge check cylinder block for flatness after cleaning it.
It will be also interesting to see how distorted the cylinder head is using the same method before having it machined flat again.
Apart from that check or replace any damaged seals or gaskets when disturbed.
By the way are you 100% sure the intial cause of the head gasket failure has been rectified?
If you need cylinder head torque settings I may be able to supply details if you let me know the Engine Series number from your chassis/vin plate.
Trust you have a good accurate torque wrench as a Forum Member recently snapped several bolts due to a dodgy torque wrench.

Toby. When Mike is talking about a straight edge here he doesn't mean an engineers rule. You need something with a "properly" straight edge. It's called an engineer's straight edge and won't be cheap to buy. Probably in the 30 to50 quid range new - good thing to look for at a "serious" autojumble. You need to check both inline and diagonally across the head. If you don't know what to do just leave it to the engineering company. The block is cast iron and much more bulky so less liable to warp, but not impossible.

Torque wrenches? For a job like this you really do need a quality bit of kit a cheap £25 special from ebay ain't likely to cut the mustard. You can lay up a lot of future grief using an inaccurate torque wrench on a job like this. I have a Norbar, and older Britool with 1/2 inch drive for everyday stuff and a 3/8 drive Halfords Advance (Made for them by Norbar) for smaller stuff. I also have a digital torque adaptor https://www.machinemart.co.uk/p/040...1_1753814583_c848edcf360bb41c80518ce94cc60ab8 which would be absolutely ideal for this job. None cost less than £50.

Presumably the head bolts will be new but remember also to thoroughly clean out the threaded holes in the block - I always run a tap down them and then blow them out with my airline. Last thing you want is crud at the bottom of the hole stopping the bolt from tightening properly.

Edit. I think I remember when I did the head gasket on Felicity - the Panda in my avatar picture - the bolt at the front centre of the head needs a pretty thin wall socket. I ground one down to fit on my pedestal grinder. Your engine should have an oil spray bar for the cam lobe oil supply - Felicity had one - If so and before you strip it but after you've got the cam cover off, with the plugs out just spin the engine over on the starter motor and take a look see that oil is spraying onto every cam lobe from the oil spray bar. Don't do it for long as it can make a bit of a mess. Probably as well to take a good look at the spark plug hole threads. Much easier to do a thread repair (helicoil or similar) with the head off than after it's back on.

A lot of engineering companies which specialize in automotive work now have the ability to pressurise and crack test the head before you spend money having it skimmed. If she got really hot, and it sounds like she may have? then this can be a good thing to have checked out?

 

[Pugglt Auld Jock]

Using a steel straight edge and 2 thousands of an inch feeler gauge check cylinder block for flatness after cleaning it.
It will be also interesting to see how distorted the cylinder head is using the same method before having it machined flat again.
Apart from that check or replace any damaged seals or gaskets when disturbed.
By the way are you 100% sure the intial cause of the head gasket failure has been rectified?
If you need cylinder head torque settings I may be able to supply details if you let me know the Engine Series number from your chassis/vin plate.
Trust you have a good accurate torque wrench as a Forum Member recently snapped several bolts due to a dodgy torque wrench.

Nice to see someone talking in thous! I grew up with them. I can easily imagine what 2 thou or 5thou or 25 thou feels like. Quote me in metric and I haven't a clue though.

 

[bugsymike]

Nice to see someone talking in thous! I grew up with them. I can easily imagine what 2 thou or 5thou or 25 thou feels like. Quote me in metric and I haven't a clue though.

"The French are widely credited with originating the metric system of measurement. The French government officially adopted the system in 1795."
Got a lot to answer for!!!

 

[Pugglt Auld Jock]

Nice to see someone talking in thous! I grew up with them. I can easily imagine what 2 thou or 5thou or 25 thou feels like. Quote me in metric and I haven't a clue though.

Oh. I just thought, I think when these went from the older OHV engine to the OHC Fire engine they also went to angle tightening for the head bolts? In fact I've just nipped out to my treasure trove of haynes manuals and yes, they're angle tightened. So, Toby, you're going to need a degree wheel too - the good news is they're cheap as chips!

 

[bugsymike]

Oh. I just thought, I think when these went from the older OHV engine to the OHC Fire engine they also went to angle tightening for the head bolts? In fact I've just nipped out to my treasure trove of haynes manuals and yes, they're angle tightened. So, Toby, you're going to need a degree wheel too - the good news is they're cheap as chips!

Nick the kids protractor to do it I timed the injector pump on a York diesel I fitted in a LandRover using one of those in the 1980s, ran perfectly although I can't remember if my children got the protractor back or not.
I do have the correct degree wheel for angles when torqueing head bolts also.

 

[tobywood13]

Thanks for the advice chaps. I’ve been typing my reply and keep adding to it as you both drop further nuggets of FIAT related knowledge!

I will carefully check the flatness of both the cylinder head and block myself just in case it somehow remained un-buggered, any indication of warping and it’ll go off to the machinists for a proper assessment.

It’s always had a slow coolant loss issue since I’ve had the car, which is why I replaced all components of the cooling system gradually. I think the head gasket has always been slightly leaky, but finally gave up entirely. I’m confident that nothing else could’ve caused the gasket to go besides the gasket itself finally giving in with a coolant channel leaking into one cylinder (misfiring on one cylinder now), it failed in normal conditions with no prior indication.

Number on the chassis plate under the bonnet is 51291672. I have a good Sealey torque wrench which I deliberately only use when absolutely necessary to minimise the chance of it going out of calibration. Every other bolt I just do up to my preferred ‘snug’ or ‘FT’ spec. It’s never failed me yet! Any tips on the torque spec and tightening sequence for the head bolts would be greatly appreciated.

Never encountered angle tightening before. I assume you torque it up, then turn it 90 degrees more for example?

New head bolts on the way. What gauge tap would be needed for these holes? No air compressor in my arsenal yet, but I’ll buy a can of compressed air as that’s better than nothing.

Doesn’t seem to be too hard of a job, compared to most cars, it’s a good car to learn how to do it. Just need to be careful and meticulous.
Worst case scenario, I’ll bung in another engine. Good car to learn how to do an engine swap too, I suppose…

Haven’t been able to consult the Haynes manual on this job yet, as it’s in the boot of the Panda which is currently elsewhere. I assume this includes a good step by step guide online how to do the job? The broad strokes, like how to remove manifolds, what belts have to be removed etc.

 

[Pugglt Auld Jock]

Nick the kids protractor to do it I timed the injector pump on a York diesel I fitted in a LandRover using one of those in the 1980s, ran perfectly although I can't remember if my children got the protractor back or not.
I do have the correct degree wheel for angles when torqueing head bolts also.

Never thought of using a protractor, good call. I have a cheap Draper one, an earlier version of this: https://www.drapertools.com/product/34571/angular-torque-gauge-1-2-sq-dr/ and it works very well.

 

[bugsymike]

The Engine Series Number should look like one of these so you can check data.
Re a tap what I do when new head bolts are required I use an old bolt and run it down my bench grinder to give it three flutes , clean of any rough edges then use it as a tap as correct thread , use a speed brace to run it down and collect the dirt etc. If no air line a good squirt of WD40 or similar will wash the dirt out and then use a rag on a thin screwdriver to dry out the holes.
My angle gauge is a Sykes Pickavant, still in original box, although very well used.

 

[tobywood13]

The Engine Series Number should look like one of these so you can check data.
Re a tap what I do when new head bolts are required I use an old bolt and run it down my bench grinder to give it three flutes , clean of any rough edges then use it as a tap as correct thread , use a speed brace to run it down and collect the dirt etc. If no air line a good squirt of WD40 or similar will wash the dirt out and then use a rag on a thin screwdriver to dry out the holes.
My angle gauge is a Sykes Pickavant, still in original box, although very well used.

From the looks of this, you tighten the head bolts to 30Nm, then 90 degrees, then another 90 degrees. Annoyingly, my torque wrench starts at 60Nm.

 

[bugsymike]

From the looks of this, you tighten the head bolts to 30Nm, then 90 degrees, then another 90 degrees. Annoyingly, my torque wrench starts at 60Nm.

These books are usually fairly accurate as used by the trade, but a good idea to check a different source of information to confirm.
When asking how tight a bolt should be the "Strip the threads and back half a turn" may not be the answer, although when asking older mechanics as an apprentice it was a popular one.