Thread: Do I have a Head problem or a shagged expansion tank cap?

Hmmm..

How long have you had the car?

Does the cooling system stay pressurised long after the engine has cooled down?

Is it running rough on startup after being left overnight?

Is it "using" coolant without having obvious leaks?

Can you hear the engine "ticking" periodically, with a repeat pattern ~ once a second when the engine is warm?

The first three point to a general head gasket / cracked block / slipped liner problem, while the last one is specific to a slipped liner. Another thing you can do is check all your sparks, and if any one looks cleaner than the others, you can bet you've got coolant entering. This is what makes it run rough in the morning - the cooling system pressurises, and the pressure slowly bleeds into the cylinder through a crack / gasket hole / between the liner & cylinder (depending on nature of prblem) and the spark doesn't spark while the cylinder's wet.

Another test is to check your exhaust for excessive liquid spluttering out from cold. Emphasis on excessive, some liquid is normal due to condensation in the pipes.

I'd say Chemweld is usually there for one reason and one reason only so, while I'd hope its only a blown gasket, I'd secretly be looking for a replacement engine. They're usually not worth fixing if its more serious than a blown head gasket.

Originally Posted by Offender90

Hmmm..

How long have you had the car? App 3-4 months

Does the cooling system stay pressurised long after the engine has cooled down?

Yes , I stays Pressuried long after the engine switched off

Is it running rough on startup after being left overnight? mmm, I'm not

sure about this one , I haven't been inside another Rangie to compare

Is it "using" coolant without having obvious leaks?

Yes , I have to fill up slighty with coolant or water from time to , it seems to drop slightly in cooland level ,but that just may be because the coolant is being pressurised and lost thru the exp tank cap

Can you hear the engine "ticking" periodically, with a repeat pattern ~ once a second when the engine is warm?

yeah I can hear an aweful what sounds like a griding noise may be not so much a ticking periodically coming out from inside the RHS of engine bay area , perhaps from the Tx / gear box but perhaps this may be a different issue all together

The first three point to a general head gasket / cracked block / slipped liner problem, while the last one is specific to a slipped liner. Another thing you can do is check all your sparks, and if any one looks cleaner than the others, you can bet you've got coolant entering. This is what makes it run rough in the morning - the cooling system pressurises, and the pressure slowly bleeds into the cylinder through a crack / gasket hole / between the liner & cylinder (depending on nature of prblem) and the spark doesn't spark while the cylinder's wet.

Another test is to check your exhaust for excessive liquid spluttering out from cold. Emphasis on excessive, some liquid is normal due to condensation in the pipes. Ok I will check tomorrow before setting of to do Comp test

I'd say Chemweld is usually there for one reason and one reason only so, while I'd hope its only a blown gasket, I'd secretly be looking for a replacement engine. They're usually not worth fixing if its more serious than a blown head gasket.

That's not what I wanted to hear

All is not lost.My disco has a slight ticking sound and pressurizes the header tank,so does the defender but neither use coolant,the disco was pressure tested last thursday and all eight plugs came out identical,smokey grey so it isn't time to panic yet.They are readily available at a reasonable price so don't worry to much.Look at it this way,worst comes to worst it would go real well with a 4.6!. Pat

Originally Posted by PAT303

All is not lost.My disco has a slight ticking sound and pressurizes the header tank,so does the defender but neither use coolant,the disco was pressure tested last thursday and all eight plugs came out identical,smokey grey so it isn't time to panic yet.They are readily available at a reasonable price so don't worry to much.Look at it this way,worst comes to worst it would go real well with a 4.6!. Pat

I like the way you think , a 4.6 would be real nice

chemi weld is a bugger to get out of the engine after you use it, if the whole thing wasnt pulled down and meticulously cleaned it will circlulate around for a long time...

it might have happened like this...

engine blows off exapsion tank blow out vavle, bubbles found in tank. Owner add chemiweld to get it home.

owner gets the head pulled and a new gasket as required (lets say it was the left one) is fitted problem has gone away, cooling system gets the drain and replace treatment.

youve purchased it and now the right gasket has decided to go south.




the level on the expansion tank isnt always right, every td5 fender Ive ever seen has the coolant consistantly turning up about 1cm to an inch below the "level" line and it doesnt matter how many times you top it up it always comes back to there and then never moves. keep an eye on your level and if it drops a cm or 2 and then stops moving Id stop worrying about it.

when you do all your other testing OOC Id fit a leak down tester and see if any pot puts bubbles into the coolant. do it cold and then hot..

if youve got the time the other check I like to use for the v8 is to give it a bit of a hard time and then park it up without shutting it down properly. leave it over night

in the morning pull the fuel pump relay/fuse then all the plugs and crank it over, (placing a piece of white gauze over each plug hole helps with the next bit) if it blows a mist out of the plug hole then coolant is getting into the combustion chamber.

Originally Posted by Blknight.aus

chemi weld is a bugger to get out of the engine after you use it, if the whole thing wasnt pulled down and meticulously cleaned it will circlulate around for a long time...

it might have happened like this...

engine blows off exapsion tank blow out vavle, bubbles found in tank. Owner add chemiweld to get it home.

owner gets the head pulled and a new gasket as required (lets say it was the left one) is fitted problem has gone away, cooling system gets the drain and replace treatment.

youve purchased it and now the right gasket has decided to go south.

I suspect that's exactly what's happend , I've owned the car for a short while and now the h/g on the otherside decided to let go...




the level on the expansion tank isnt always right, every td5 fender Ive ever seen has the coolant consistantly turning up about 1cm to an inch below the "level" line and it doesnt matter how many times you top it up it always comes back to there and then never moves. keep an eye on your level and if it drops a cm or 2 and then stops moving Id stop worrying about it.

when you do all your other testing OOC Id fit a leak down tester and see if any pot puts bubbles into the coolant. do it cold and then hot..

Where would you Normally fit the leakdown tester Dave ? sorry to sound clueless?

if you've got the time the other check I like to use for the v8 is to give it a bit of a hard time and then park it up without shutting it down properly. leave it over night

let's says I do the Wet / Dry Comp test and give it a hell of a time ,taking into account the COMP readings are normal , how does one ensure the engine not shutdown properly , do you mean not switch it off ? and let it Idle ? and if so for how long?

in the morning pull the fuel pump relay/fuse then all the plugs and crank it over, (placing a piece of white gauze over each plug hole helps with the next bit) if it blows a mist out of the plug hole then coolant is getting into the combustion chamber.

this sounds like a 2 man job where one cranks the engine and the other holds down a White gauze over plug hole?

As above Post, both my LR's loose coolant when I change it to a level and then stop.It is a bit below the seam line on the header tank but they both stay there. Pat

let's says I do the Wet / Dry Comp test and give it a hell of a time ,taking into account the COMP readings are normal , how does one ensure the engine not shutdown properly , do you mean not switch it off ? and let it Idle ? and if so for how long?

He means give the motor a hard blat .... IE race around the burbs // lots of revs 3 to 4000 rpm ... get the whole system real hot ... drive & race it into the garage and shut it down immediately

Then test the next day



Some peace of mind on coolant levels ...
My RRC tank always is at about "just below half level" when cold ... any higher and it just blows it out .. and my motor is fine

check the tank for fill level when the motor is warmed ... not cold ... as this will give you a better idea of how high the coolant level should normally be

Recheck the level the next day when cold .... and then compare the levels for coolant usage from there


It just might be a case of constant overfilling thats giving you grief ... rather than you have a problem

I hope it's just a case of the above that I have wrote ... rather than the item that you suspect