Driving in my car last night, and there was a slight knock sound from the engine bay, so i pulled over and it seemed to be idling roughly. Stopped up for a bit, and checked under the oil filler cap, and theres a light browny type mayo looking material. When I drove the car home, it seems to drive fine, and theres no sight of it overheating at all.

I can service the car myself fine etc, but have never done anything major on the car bar changing the whole exhaust from cat back, so do you think there is anything i could try? Does anyone know what the possible problem may be, and how much I may be looking at to fix? (money is well tight after just takin out my first mortgage)

Cheers in advance for the great advice I always get back!

A bit of mayo-type stuff under the filler cap is not so surprising if you do a lot of sitting around in traffic. If you do mostly motorway miles it's more likely to be a sign of trouble. But I can't think of any reason why anything to do with the head gasket should cause knocking noises of any sort. Check valve clearances because it's very easy to do (the Haynes manual on any pushrod-engine car will give you the general idea on how to do it - clearance on the Skoda 1300 is 0.2mm in and ex): also look after the basics like spark plug gap and condition, which could easily give you a rough idle if wrong - and look for other signs of trouble on the plugs while they're out (for instance, if one of them looks significantly different from the others in terms of wear, nose colour etc. it could be an indicator that something's wrong with one cylinder).

If it does turn out to be head gasket, a gasket costs about £25 IIRC, and although you should ideally get a head skim (£30 last time I had one, though that was probably over 5 years ago) and new cylinder head bolts, plenty of us have dispensed with both of those and lived to tell the tale. Fitting the gasket on the 1300 is a piece of cake, the only special tool you need is a torque wrench and even if you can't beg, borrow or steal one they are about £15 these days. The only mistakes you could make that would really knacker you, apart from well obvious stuff like leaving bolts out, are forgetting to drain the coolant before you start, and forgetting to connect the oil feeder when you put the head back. If you decide to go ahead and give it a go yourself, report back here for more tips!

a little mayo can be condensation, but lots if it would indicate a head gasket.

i've just done the head on my 1.6 . as said before, have it skimmed and get new bolts as for the gasket, you can usualy get a "head set" that will have all the seals/gaskets you need plus more.

to get this done at a garage is silly money, £700+. but if you can spare the car being off the road for a few days, then go for it.

Torque Wrench - Screwfix.com, Where the Trade Buys £12.49 you also need a 10mm hex key 1/2" drive attatchment, I picked up a nice one for about £6/7 from Halfords. One of those long wheel braces will help get the old bolts off if they're stuck.

Knocking -Have you got plenty of oil in?

As for the mayo i wouldn't worry about it as it is likely to just be a bit of condensation. Mine is the same and has done about 80,000 miles. So long as you put new oil in every 6,000 miles and change the coolant every 2 years and don't nail it all the time it should see you right for many miles to come.

I had an old triumph acclaim in the past and i drove that until it was making frothy coffee for me! I drove that until it physically couldn't cool the engine.

:P

change the coolant every 2 years and don't nail it all the time

The coolant system is sealed and there's no reason to change the coolant - in fact it tends to give more headaches than it solves due to limescale deposits and introduction of more oxygen (more rust!) to the system. And as for nailing it, engine reliability is usually best when it's driven hard within the 2000-3500rpm (on an oldish lump like the Skud 1300) range. Driving hard at low revs causes bearing failure, high-revving wears everything, but at a nice steady 3000 a bit of heavy throttle is actually good for it - drives out condensation, keeps bores clean etc.

Was there something about antifreeze/rust inhibitor evaporating and thus becoming less protective over time ?

And what does 2000/3500 rpm equate to in mph in 2nd 3rd 4th in a 1300 ? Cos I dont possess a tachometer.

Thanks for the advice! I service the car every 5000 miles, and theres still plenty oil in it. The knocking doesnt seem to be an issue now, just the mayo, and I have noticed some white smoke coming from the back. Just think I will bite the bullet and go for changing the headgasket.

Pinkskud you said it would take a couple of days to do, any indications on cost? Also, what does having it skimmed involve?

Thanks anewman, torque wrench has been ordered!

Was there something about antifreeze/rust inhibitor evaporating and thus becoming less protective over time ?

Yes, in the days of non-sealed systems that was an issue, and if your cooling system has deteriorated (like mine on my Favorit) so that it no longer holds a reasonable amount of pressure then maybe that's an issue - but modern antifreezes do basically go on for ever and the rust inhibitor certainly does. I've never changed the coolant on any car for any other reason than having to drain it to do a head change or something, and often not even then. The only trouble I've had with blockages was a Favorit where some previous owner(s) had routinely topped it up (the fact it needed topping up suggests there was a leak) with just water and the cabin-heater matrix was so blocked I had to remove it, dismantle it, and rod it through. Never seen anything like it! By contrast, when my mate terminally pranged his 1994 Granada a couple of years ago, the original antifreeze was still in it and looked like new after 150,000+ miles.

The actual job of swapping a head gasket takes less than 2 hours with practice, or a long morning or afternoon for a first-timer. Use your skill and judgement to see what needs taking off: for instance, obviously you have to take off the injection assembly but you can usually leave a lot of cables and stuff in place and just undo the assembly from the manifold, or the manifold from the head, and swing it out of the way. Ditto exhaust - here's it's usually easiest to undo a union under the car somewhere first 'cos exhausts don't bend! I find on 1300s the exhaust manifold is more likely to come off the head without trouble (for all the nuts are helluva inaccessible - you'll need a ring spanner or a socket on a wobble extension) than the pipe off the manifold. Drain the coolant.

Get the rocker cover off (the gasket should come away from it and the head intact), and undo the oil pipe union to the rocker shaft. From memory, there are 10 bolts and 4 studs, or something like that, on a 1300. Make sure you've got a good quality socket to undo them - if you knacker the heads you'll never get a pipe wrench on there! Best is to crack them off a quarter-turn at a time each until they are loose, then spin them off.

Because the 1300 is a pushrod lump you have no timing belt to remove, and in fact if you aren't going to get a skim (see below) you can theoretically leave the rockers in place. However, it's very easy to remove - just undo the two bolts on each of three (I think) pillars, a little at a time, until they're all slack, then spin them off and pull the whole assembly away. Careful - it may fall apart in the middle (can't remember). Take the pushrods out. Always keep pushrods in order. Usual trick is to push them through a bit of cardboard in sequence so they can't get mixed up. If you are going to get the head skimmed you'll need the rocker gear off it, of course.

Now you can pull the head off. I've never had much trouble with Skud heads, but if it's reluctant try tapping it with a wooden mallet here and there. I know some folks who just spin the starter motor but I don't like the idea of the head jumping off and falling on the road! The Haynes manual is full of dire warnings about disturbing the liners in the block, but in practice they're normally rusted tight and would need a hydraulic press to shift them. Have some kitchen paper handy to wipe any spilled coolant out of the bores before it causes rust and/or gets into the oil.

Skimming means putting the head upside down under a milling machine and taking off enough metal to leave a smooth, clean, FLAT surface. Ask around or use your local Yellow Pages to find an automotive engineer who can do that. You'll normally have to remove the valves for that: it's perfectly possible to skim a head properly with valves in place but machinists don't like it, it's about 2 minutes'-worth of extra bother. Again, keep valves in order. Removing them is easy with the proper tool (from any motor factor), but the collets like to freeze in place and usually need some encouragement to free off with a hammer. If you're really dedicated, polish the valves to a mirror finish while they're off - it helps breathing and if they're really shiny they will last a while before building up new soot and gunge deposits. Use common sense removing and refitting valves: if the removing tool slips off the springs can send things quite a distance, so don't lean over the work!

While the head's off, make sure the top of the block is clean of carbon and bits of gasket. A cheap steel ruler makes a good scraper. Clean the piston heads if you can be bothered, and carefully remove all loose bits of muck afterwards.

Putting the head back is the reverse of removing it! Follow tightening instructions for the head bolts. I've had one or two threads strip, which is a real pain: the only fix is a 'Helicoil', which requires a bit of careful drilling out of the hole and fitting of a steel thread insert. Be careful when refitting rocker gear to ensure no pushrods are left out, or contacting in the wrong place. You'll need to reset clearance whether or not you've had a skim.

Hm, that looks a bit frightening, doesn't it? Honestly, do two head swaps on pushrod motors and you'll regard it as hardly more trouble than doing a couple of front brakes. Good luck!

:)All great advise, but IMHO doing a head gasket change in 2 hours would be a bit of a rush even with experience. As you said it's important to make sure all the gasket surfaces are very clean, this on it's own can take nearly as long as the spannerwork! It's also important to ensure the liners protusion is correct.

Whatever you do, please don't use the starter to release the head from the block, or turn the crank after the head is removed. The liners may well go up and down with the pistons!

The old Skoda engine is a doddle to work on though, and is an ideal engine to train on.

Go for it, we are here to advise if you get stuck.

but IMHO doing a head gasket change in 2 hours would be a bit of a rush even with experience

Well, all right, maybe the passage of time has made me look on it more favourably, as you might say....

Watch out for the Alternator bracket- took 3x longer to get that barsteward sorted than it did to strip the head and replace gasket!

As Daverapid says- just holler if you get stuck!

cheers guys! All ordered up today, so waiting on the parts arriving tomorrow hopefully. Just ordered a full gasket kit, saves the hassle of missing anything out i hope! so expect something on here if anything goes wrong :P

Ross

once did an estelle HG in 55minutes

anyway, white smoke and knocking? doesn't sound as simple as a HG to me - white smoke would be but sure they dont clatter when the HG is gone?!

The coolant system is sealed and there's no reason to change the coolant - in fact it tends to give more headaches than it solves due to limescale deposits and introduction of more oxygen (more rust!) to the system. And as for nailing it, engine reliability is usually best when it's driven hard within the 2000-3500rpm (on an oldish lump like the Skud 1300) range. Driving hard at low revs causes bearing failure, high-revving wears everything, but at a nice steady 3000 a bit of heavy throttle is actually good for it - drives out condensation, keeps bores clean etc.

Sorry Richard but i am going to have to disagree with you on the coolant as I do not believe that there ever is a truly sealed system and have had a series of cars of all makes with supposed sealed systems. None have ever been truly sealed including the skoda and require a small amount of topping up from time to time. I have also had a fair bit of experience in flushing out systems on previous cars because coolant wasn't changed with chunks present.

I agree with your other comments though but what i meant by nailing it was redlining it!

My Favorit used to let a little coolant disappear and need topping up. After flushing it out, changing the thermostat and replacing the heater matrix it doesn't seem to have lost a drop in a long while - but I suppose that's more luck than any skill in my case.