Head gasket case

Hi,


I am suspecting a head gasket failure but would welcome any ideas.
I have a 96' P38 4.0 V8 which has started pressurising the coolant and as a result it is loosing a significant amount without any visible leaks.
It has been using far too much fuel as well in my opinion. There is no white emulsion in the oil but i hear these things can deteriorate if left.
I have four options apparently,
First is to change the head gaskets, second to change the engine,
third to scrap the car and fourth to try a sealant like irontite in the hope it might solve the issue.

I am not made of money, my worry is that if i change the gasket and then something else goes wrong it is a waste of time. She is not a young vehicle also...

I also read that irontite sealants are not guaranteed and are not the best of ideas anyhow...............do the job properly is what i digest.

What sort of cost should be involved in changing the gaskets or engine?
Is irontite a good idea?


It has a LPG conversion, tidy inside and out, lots of new parts replaced over the past year and regular oil changes - still i fear no one wants a project!
Last question: If i replaced the gaskets how long should the engine be good for, or is then prone to further failure?


thank you for your time................

if it where mine id warm engine and check rad is hot all over core and so cooling ,all hoses hot so thremostat working remove heads ,check gaskets ,block with clamp both water ways one bank at time,make plate with tyre valve for front water way behind front cover ,fill that bank with hot water as hot as possible, pressurise block 30-40 psi check liner edges for leaks,leaks fit top hat linered block ,doesnt fit head gaskets

irontite is a temp repair but is proberly the best sealer you can use if treatment is done correctly all other sealers are a waste of time!

96 my rr p38a at the age is going to need cam followers and some major work to the engine if it is a porus block swapping it out for another will only be a waste of time there are no decent blocks out there i average one-three rebuilds a month at the moment and one every two months is a second hand swapped engine which is worse than the one that it replaced!

i would have it done and checked before throwing good money at it if you want to keep it