Head gasket blowing??????

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Clive46s
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Head gasket blowing??????

Post by Clive46s »

I have an early model Ford Dexta(957e 14309) recently I had an occaisional misfire. Gave her a good service included cleaning up Injectors and she ran a lot better. Week or two later started her up and heard a ticking noise like an exhaust gasket blowing, further investigation showed that there was mix of water & diesel
flowing between head and block (gasket) naturally assumed that the head gasket had blown so bought and fitted new h/g tarqued her down to 60lb/ft. Tried to start her and found that diesel vapour was still blowing out worse in fact, I had the head skimmed which was warped refitted head situation no improvement and loosing too much compression to start. HELP!!!!!!
N.b. blowout was beneath the exhaust manifold, ther was a slight leak with combustion chambers and new gaskets have been fitted.

pbufton
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Re: Head gasket blowing??????

Post by pbufton »

cracked liner perhaps?

Tubal Cain
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Re: Head gasket blowing??????

Post by Tubal Cain »

Hi,

It would appear that you have lost compression on all three cylinders! You say that you have fitted new gaskets to the combustion chamber caps?

If that is so, were they the full face gaskets which are now being supplied as against the copper ring gaskets?

If the answer is yes and you still have the original copper ring gaskets heat them with a blowlamp until they are red hot let them cool and refit them. By heating the copper you will soften it so allowing it to be compressed..

Over time the combustion chamber caps become distorted around the bolt holes and if you refit them with a full face gasket they are unable to make a seal with the cylinder head due to this distortion. You can check the caps with a straight edge to see if they are distorted. If you do find high spots they can be removed with careful use of a file at the edges of the caps.

Gerald

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Re the liners, I have checked as best I can with lights and magnifying glass but nothing obvious thanks anyway. REgarding the combustion chamber covers. I have fitted the new type of "triangular" gaskets, and there is a little leakage, but the problem that surpasses all others is the amount of diesel vapour that is being forced out, between the block and head. WE tried to tow start her, just to get her fired up, but there was so much loss of compression, that we had no chance. It was chuffing that bad that it sounded more like an old steam loco! Anyway thanks so far. I am wondering whether in fact the block is warped? However most of my local experts feel that this would be very unusual? Any more tips welcome

PghBill
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Re: Head gasket blowing??????

Post by PghBill »

To lose enough compression to prevent starting seems like more than a gasket leak to me. Have you checked you timing? Valves not closing or opening at the proper time could cause a major compression loss.

Nick
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Re: Head gasket blowing??????

Post by Nick »

Its obvious to me that if the gasses are coming out between the block and head, something has to be warped or faulty. Did you fit the correct head gasket? It should be copper. If yes, then when you take the head back off, put a straight edge accross the block and shine a torch, see if you can see light under it. While your at it, check the head aswell just incase.
Had the head been skimmed before?
It could possibly be that something got stuck under the head or the gasket got damaged when the head was re-installed so it wouldnt clamp down tight enough to create a seal.
Let us know what you think.
Oh yay, look, another seized bolt! Lets get a hammer.....and some kano.....and some cider!

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Many thanks pghbill but I think that the gap between head and block is the cause of loss of compression and nick, unfortunately seems to be pointing me in the direction that I was really trying to ignore. Nick many thanks for your comments. I don't know if the head has been skimmed before, it's quite possible as she has over 7k hours on the clock, and of course something like 50 odd years behind her. I have tried the straight edge across the block approach, but it hasn't really been conclusive or at least that's what I had myself believe. My only hope of it not being the block are that having checked the studs, I was able to screw them into the block a few more threads. The only other hopeful bit is that having taken the head off and replaced it now about four times, that I did it with the water/thermostat housing in place rather than fit the head and then the housing. The reason that there may be a glimmer of hope here is that at some stage someone has welded a piece into it and I wonder whether this may be distorted, causing it to touch the block before torquing up. THis of course could prevent the head going down square. So I have now commenced putting it back together gingerly. It was your suggestion about something preventing it going down square that made me rethink matters. I will post result when completed. Oh the gasket is the copper one, initially supplied by Agriline and the second one was from Phoenix at Hereford who specialise in tractor engine rebores etc. So here's hoping!!!!!
Clive

tom lad
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Re: Head gasket blowing??????

Post by tom lad »

hi

any chance of photos ??

good luck
Some mornings I wake up grumpy, but most mornings I let her sleep in.

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Morning Tom Lad, just going out now to replace thermostat housing and retime her and going to turn her over yet again to see what happens!!! Being a bit of a pessimist can't think that the problem will be sorted, so what would you like photos of?
CLive

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Re: Head gasket blowing??????

Post by PghBill »

Clive
Hope it works out to be something as simple as the thermostat housing.
Keep us posted

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Thanks for all good wishes, however, having put everything back together and turned her over, out came the diesel vapour, exactly as before, blowing out through the gasket below the injectors. if you can let me know what photos you would like to see, Tom lad, I will download them
clive

tom lad
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Re: Head gasket blowing??????

Post by tom lad »

hi
so the gas is comeing from the head gasket joint .

which bit was welded ?
Some mornings I wake up grumpy, but most mornings I let her sleep in.

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Good morning Tom lad
yes that's right, the vaporised diesel is blowing straight out, about midway along the head gasket, below the exhaust manifold. The bit that was welded was the underside of the thermostat housing just above the bottom right retaining bolt (when looking from the front). Having tried to start her up yesterday she was firing, but clearly didnt have enough compression to fire all three cylinders, when I took the head off again, no 1 cylinder was dry (so assumed that was firing) but no2 and no3 were saturated with diesel. This corresponded to the blow out area (trust this makes sense)
Clive

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Re: Head gasket blowing??????

Post by ol'Blue »

I have been following this along and wondering to myself what might be causing this issue. As long as the head is off at the present, I believe it might tell us some info if you could set the head down on the block with NO gasket in place, and use a very thin feeler gauge in the area of concern.

Lay the feeler gauge on the block. put the head down on the block with just gravity, and a couple loose bolts holding it in place. then every inch or so along the surface insert and pull the feeler gauge in and out. if yo u have little to no resistance between those 2 cylinders then you have confirmed your thoughts.

This test wont tell you which surface is warped, but, this might at least confirm or deny your suspicions.....

Are you absolutely sure your torque wrench is in spec??

are you putting a little oil on your head bolts before torquing?

Any chance you have debris in the bottom of the bolt holes in the block causing the bolts to bottom out before they can clamp the head??

Is there an update to the torque sequence for the new style gaskets your using??

Is the head gasket different between the original dexta engine and the super dexta?? (different bore)


I sure hope you can get this figured out, hate to see a good old Dex. parked......

dave
1964 Super Dexta, ol'Blue

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Thanks ol'blue - I have been chewing over your helpful suggestions - shan't do much today though as I have just got home from dentist who kindly removed one of my upper molars! - anyway with regard to your thoughts ---- I will try the feeler gauge suggestion.As the head has been skimmed by a reputable company it is likely that any defect would relate to the dreaded block! Not 100 per cent sure about torque wrench, but have compared mine with my sons and they do match settings etc. I didn't use oil on the stud threads as I'm sure I've read somewhere that you shouldn't. Is that right? As to debris in stud holes, I have done a few but they were clean. -- perhaps I should do the rest to be sure. I have actually begun to wonder whether I should replace all studs, as I have now stripped the thread from three nuts (torquing them down so many times now) I haven't seen any updates re new gaskets torques, but the new ones certainly appear identical to the original Perkins that I took off. Actually I have been wondering about the gaskets, but the suppliers have assured me that they are the right ones for the job. -- I might just revisit that query though. Thanks for all the food for thought
Clive

ol'Blue
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Re: Head gasket blowing??????

Post by ol'Blue »

I have always used oil on my threads when torquing down an important component. Your torque wrench does not know the difference between 50lbs of clamping force or 30lbs of clamping force and 20lbs of galled thread, dirty thread, and friction between the head of the nut/bolt and the clamping surface. The purpose here is to get an even clamping force between all your head bolts/studs, so as to hold the head down flat and even.

If you have any studs/bolts that have been compromised, lets get them freshened up and by all means clean the rest of the threads up nice.

If you are using bolts down into the block, use an appropriate tap to clean and renew those internal threads also.

if your using studs and nuts, you should be able to spin each nut down on the stud, by hand, past the point that it would contact the head if the head were on at that moment.

using a little oil under the nut and between the washer, will allow it to achieve a more true clamping pressure, rather than adding rotational friction to what your torque wrench reads.

I believe in my heart, you had in the beginning a simple head gasket failure. And since then for what ever reasons, you have not been able to get the head and gasket back into the original clamped position.....

Good luck with the tooth......ouch....

dave
1964 Super Dexta, ol'Blue

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Re: Head gasket blowing??????

Post by Bensdexta »

ol'Blue wrote:As long as the head is off at the present, I believe it might tell us some info if you could set the head down on the block with NO gasket in place, and use a very thin feeler gauge in the area of concern.
Lay the feeler gauge on the block. put the head down on the block with just gravity, and a couple loose bolts holding it in place. then every inch or so along the surface insert and pull the feeler gauge in and out. if yo u have little to no resistance between those 2 cylinders then you have confirmed your thoughts.
As a variation of this technique, perhaps you could clean both head and block mating surfaces spotless and mark say the head, with tool-makers blue die.

Then gently clamp it down on the block snug, remove it and see where the dye appears on the block. Dye will appear at the hard points and will show you where any gaps are.
Bensdexta - 1961 working for a living!

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Hello one and all. Many thanks for all suggestions so far. Well I have not gone into hibernation, but have been doing a bit of networking locally. I have found a local dexta man of many years experience ex fordson franchise service manager etc. He agreed to come and have a look at my engine and so I held off doing any more work on her. His immediate response was to say that the block and head seemed fine and he did not think that the problem was head gasket related. We put her back together,having cleaned up the combustion chamber covers and refitted them etc etc. I turner her over, and low and behold out came the diesel vapour after a metallic clicking sound. We both observed the vapour coming out and although it appeared that it was coming from the headgasket, my new found friend assured me that it was from the ccc's. He agreed that it looked like head gasket but felt that it was simply the effect of the pressure from within. I am yet to be convinced. However, I have now ordered a new set of ccc's and gaskets from Agriline and await delivery!!!! I will keep you posted!!
Clive

ol'Blue
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Re: Head gasket blowing??????

Post by ol'Blue »

Is there another name for "ccc's" I am confused, but glad you got another set of eyes on the Dexter with you....

dave
1964 Super Dexta, ol'Blue

PghBill
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Re: Head gasket blowing??????

Post by PghBill »

Dave,
I'm sure he is referring to Combustion Chamber Covers.
Bill

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Sorry folks, yes ccc's was my lazy abbreviation for combustion chamber covers -- still awaiting delivery
Clive

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

well Im back again!! Update on progress. After a fairly lengthy wait, the combustion chamber covers arrived on Thursday, together with new gaskets, and an exhaust manifold (as the old one crumbled apart after Id taken it off again for the umpteenth time) Yesterday a.m. my new found friend and I set to work replacing the covers etc. When she was finally back together we topped up the water and started turning her over. Eventually, aided by that stuff I try to avoid (easy start) she coughed into action, blowing smoke from every conceivable orifice. As she warmed up, the combustion chamber covers improved until only a small amount of fuel vapour etc was being blown out. She started to run very smoothly for a while then low and behold out poured water from the overflow pipe!!! On further checking there was evidence of bubbling and pressure, as the water poured out until only a small amount was left in the system. We concluded that after all this, there was a crack or similar in the head? We hypothesised over a pot of tea (and roll up in my new friends case) and decided that possibly, there had been so much pressure escaping from the combustion chambers,that there was little pressure going into the cooling system. Now that we had blocked off this escape (by replacing combustion chamber covers and gaskets) the pressure was going back into the cooling system hence the bubbles in the water and continued overflow. Help!!! Are we now on the right lines? Is it a cracked head after all? Are there any other likely causes e.g. Liner cracked. I don't really want to buy a new head if there is the possibility that the cause could be somewhere else!! Can anyone advise further please!
Clive

Nick
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Re: Head gasket blowing??????

Post by Nick »

You could have your head crack tested, that would save you buying one if it isnt cracked. i think they are only £150 from agriline, a new head with valves etc
Oh yay, look, another seized bolt! Lets get a hammer.....and some kano.....and some cider!

Aussie Frank
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Re: Head gasket blowing??????

Post by Aussie Frank »

Hi Clive,

I find that if I try running an engine after it has just been reassembled with the radiator cap on sometimes you can get an air lock in the cooling system which will cause the symptoms you experienced.

I would start it one more time with the cap off and just top up the radiator as needed. If it still bubbles furiously you probably have a cracked head or gasket problems. If it settles it will have been an air lock. Normally I would have expected at least some other signs in the way it was running if the head was cracked, although it may only be a minor miss.

You are not likely to have a cracked liner causing this as they are dry liners.

Regards, Frank.
Real tractors don't need tin work to be beautiful.

Clive46s
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Re: Head gasket blowing??????

Post by Clive46s »

Hi Nick
Many thanks for your thoughts. The evidence now is pointing pretty much towards a cracked head, which is showing more now that the combustion chamber covers have been replaced plus their gaskets. having weighed up all the facts, and having discussed the matter with my local Dexta friend I feel that the best option is not to bother with pressure testing the head, as this does appear to be the cause of all problems. The cost of a test is £45 + vat plus a fair bit of travelling, so I really feel that it would be better to put the money towards a head.
Hi Frank
Many thanks for your thoughts also. I have run her several times now, having filled the water system many times over and she is still pushing out water, bubbling and blowing out like a kettle when warm. I can only conclude that as you say, the problem lies with a crack etc THanks for the confirmation re liners, as that was at the back of my mind. As you see from the above I have decided to go for a cylinder head and have one on order at this very moment (plus all of the flaming gaskets again of course). So thanks again folks. I will update, hopefully towards this coming week end
Cheers
Clive

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