I'd be really grateful for some advice on this.

I bought this Felicia: http://tinyurl.com/2wfepw on eBay last week on the basis the engine had seized. It turns out it hadn't seized but was failing to turn over due to coolant in the cylinders as a result of major head gasket failure. As soon as I cleared this the engine started fine, I ran it briefly and all seemed well apart from the obvious symptoms of a blown head gasket.

I have now removed the head and as far as I can see, there is no protrusion of the wet liners above the block. From what I have read, I understand there is little point just skimming the head and replacing the head gasket unless I also shim the liners to obtain the correct protrusion.

My question is whether this involves stripping the bottom end of the engine to push the liners up from below, or can it be done from on top? If it is going to involve a lot of further dismantling I reckon it's not worth it and I would be better off getting hold of a secondhand engine. But if it's possible to extract the liners from the top (how?) and just put in some shims, maybe that is feasible.

Any advice would be much appreciated!

You wont have to strip the whole bottom end, but you would have to remove the sump, and tap them up. theres room for maneouvre around the crank etc to get at them.

Thanks for the quick response. Do the pistons and conrods have to come out?

Would you say it was worth doing this or would I be better to get a replacement engine? - this one has done 70000.

Depends on how well you want to do the job really I would guess you could do it with them in place, but it wouldnt be recomended, Anglesmight get a bit odd for getting the pistons back into the liners and theres a chance of ring damage etc, but then there is if you things badly with the engine out of the car.

70,000 miles on these engines really isnt too bad at all, Ive heard of them going on to 180k before the body on the car gave way and the car was scrapped. My self Ive had them at around 130k running absolutely fine on nothing more than regular servicing.

Id say with the liner heights being out the right way to do it is to drop the block out remove the crank assembly, and knock the liners out etc out of the car, then put it back together with a new tiing chain, should give a good 100k more life yet, however if youve got to take the engine out anyway the temptation to spend £100 on another engine and drop that in instead of bothering to do the shim work has to be quite strong.

If you are going to replace the engine you will need to make sure you replace it with the same type, although the same basic engine has been around since the 60's there are lots of variants. You need to know if you have the 135 low compression or the 136 high compression type, its stamped pulley side of the block.

I suspect your engine is going to be MPI which you would need to make sure the donor engine is as well, the Carb and SPI variant of the engine had a different cylinder head, and so fuelling and ignition will be slightly different.

Thanks, that's extremely helpful.

You are right, my engine is a 136 MPI; wasn't aware of the different cylinder head on an SPI, so that is vital information. My initial reaction is that if I could locate a decent engine for £100 I would probably go for it as by the time I had the head skimmed and bought parts for mine it's going to be close to that anyway. On the other hand, finding one fairly local to me in the Glasgow area may not be easy and the cost of delivery may be a killer. Also, it would be nice in a way to keep the original engine, so the decision's not yet made!

no you cant do it with the pistons still in place because there's no way to compress the piston rings to re-insert them back into thier bores afterwards..

to do the job properly you need to thoroughly clean everything too, a little bit of crud trapped under the liner wil cause no end of problems, it is a skilled job doing it right and requires accurate measurements to be made, i would deffinately scrap that engine and find a decent one from a breakers yard, or even scrap the whole car and get another one off ebay

I wouldn't remove the engine. Drop the sump, remove pistons and rods, knock up the liners. Getting the height of the liners correct is a matter of trial and error with a selection of shims, time consuming but easy enough. Make sure everything is very clean, scrape out all the silt that will have built up. 70,000 miles isn't a big mileage, it'll do that twice again if looked after.

Thanks for the advice; there is something of a range of views there!

I thought I would just say what I have decided to do. I am certainly not going to scrap the car - bodily it seems to be excellent which is the most important thing and it is far better than I had any right to expect for £46. I bought the car in the expectation that the engine would probably be scrap, so anything better than that would be a bonus.

I have decided at this stage that I should not sink a lot of time and effort into the engine, since I know very little about its history. Although it appeared to run OK once I released the hydraulic pressure preventing it turning over, I simply don't know whether its life may have been shortened by being run with a badly blown head gasket and it would be a pity to invest hours of work only to have the bottom end give up after a few miles.

So I am going to restrict my work to what I can do from above. I have taken the head in to be skimmed today and ordered a new head gasket and I hope to fit these later this week. I have also managed to convince myself that there IS in fact some protrusion of the cylinder liners and that all may be well. I wonder if it is possible that they have risen up slightly after the head being off for the last 24 hours?

Finally, I am aware that head gaskets should normally be fitted dry, but I am wondering whether anyone has experience of using Wellseal gasket compound in conjunction with a new gasket on these engines. I have read some very positive comments about it elsewhere, including its use on wet liner engines, and I am tempted to give it a go.

You need to measure the liner protrusion its not much you need at all 0.07 to 0.13 mm! with a maximum of 0.04 difference between any of them. The amount youve convinced yourself you have may actually be fine but best to measure so you know for sure.

I wouldnt use any sealant myself, more likelly to be a weak point than fix a problem. But will let others advise on that if they have any experience otherwise.

Daverapid is a mechanic by trade and long term skoda enthusiast I would take any advice from him seriously, Im a fair home mechanic and rally driver, I know a fair bit about tuning, and theory and have more experience than most home mechanics due to the rallying but Dave does the job 8 hours a day every day.

i wouldn't ue sealant on a cylinder head gasket at all unless it was specified by the gasket manufacturer.

the liners shouldn't move when the head is removed, unless you've turned the crank

all this talk of liners and the like is a bit scary, are you sure the liners and knackered?? it may just be filling with water because there is a hole in the gasket, or even the possibility of a crack in the cylinder head

They can shift and the measurements involved are so precise that it doesnt take much to cause a problem, the shims themselves can break up, a heag bolt can be over tightened etc etc. Only way to be sure is to measure every time you have the head off.

Got the head back from skimming this afternoon and I am planning to reassemble tomorrow, so we'll see how it goes (or not).

Roadside Rescue quoted me

did you get car fixed?

Yes, the engine started first time after reassembly and has now covered 250 miles since the head gasket replacement with no sign of any problems. I'm not counting my chickens just yet but the signs are good. Thanks again to all who gave their advice.