14 replies to this topic

[jackog_mayfair]

hi guys
i recently posted a topic about whether or not i had blown my head gasket or had a piston slap. so to find out i am changing the head gasket. so this is basicly to get instructions on how to change it. me and a friend are going to change it tommorrow but dont have a clue where to begin. so if any of you have a link to some web page or have good instructions we could follow it would be much appriciated.
thank you
o by the way its an austin mini mayfair 1989 998cc!

[danrock101]

take the head off, take the old head gasket off, put the new head gasket on, put the head back on




Should be a guide in haynes
Basicly
Take everything off the cylinder head
undo the head nuts in the spiral pattern
if it doesn't come off then you've forgot the bypass hose
pop new gasket on
head back on
nip the head nuts up then torqe them up in the spiral pattern, you can do it in 2 stages say to 35 lb/ft then 50 or 60 what ever you're going to do them up to, I always do it about 60.
change the oil
top up the coolant
set the valve clearances
run it around a bit, re-set valve clearances
but don't forget to put everything back on the cylinder head first (manifolds, hoses, leads, bypass hose! etc)

Edited by danrock101, 28 April 2011 - 02:29 PM.

[hepple]

Make sure you clean both engine and head surface thoroughly with 240 sand paper and a block of some sort with a flat surface. I made this mistake and it lasted around 5 miles . Also, it might be worth getting your head skimmed in case its warped.


James

[998dave]

As above, buy a Haynes, it tells you, with pictures what to do, and has the torque settings in.

[Liam Mini 35]

1) Undo the accelorator and choke cables from the carb.
2) undo the bolts at the back of the head that hold the carb and exhaust on, remove the carb (you may want to remove the engine steady to allow you to pull the engine forward so you can get the carb off
3) disconnect the radiator hose and heater bypass hoses. Caution lots of water
4) remove the rockers
5) loosen off the head nuts in the required sequence. Dont remove one at a time! May cause head to warp
6) remove cylinder head
7) remove head gasket
8) clean block and head surface
9) fit new gasket unsuring it is on the correct way round
10) refit head etc reverse of removal

Hope that helps.

Edited by Liam Mini 35, 28 April 2011 - 02:55 PM.

[998dave]

1) Undo the accelorator and choke cables from the carb.
2) undo the bolts at the back of the head that hold the carb and exhaust on, remove the carb (you may want to remove the engine steady to allow you to pull the engine forward so you can get the carb off
3) disconnect the radiator hose and heater bypass hoses. Caution lots of water
4) remove the rockers
5) loosen off the head nuts in the required sequence. Dont remove one at a time! May cause head to warp
6) remove cylinder head
7) remove head gasket
8) clean block and head surface
9) fit new gasket unsuring it is on the correct way round
10) refit head etc reverse of removal

Hope that helps.

1) And fuel line, and carb overflow, and PCV return pipe.
2) Should be nuts and studs and requires studs to be removed.
3) Drain into suitable collection device by removing lower hose, then dispose of coolant responsibly.
4) Can't be done until after 5.

This is why you should just use the Haynes...

[jackog_mayfair]

thanks for all the suggestions people they are all helpfull and have given me an idea of where to begin. i will purchase a haynes manual as well!

jack

[998dave]

Will have to be the dark blue one or later for a 1989 car.

There's a light blue that only runs up to 1988, though it will still have most things you need.

[jackog_mayfair]

Will have to be the dark blue one or later for a 1989 car.

There's a light blue that only runs up to 1988, though it will still have most things you need.

thank you for your help!

[lapider]

take your time make sure both machined faces are clean and try and get any carbon or old gasket off.

and while your at it you could de coke the head.with the two outer pistons elivated i put a rag in the two lowerd pistons that are now siting down in the bores and cleaned up the raised pistons with fine wet and dry sand paper and a wire brush drill attatchment. then rock the car whilst in gear or spin the fan in neutral to get the two piston tops that were originilly recesed within the bores to lift to the top and do the same on them. you may want to re seat the valves where youl most likley need this tool

http://www.minisport...OL660210SP.html

to remove and replace them and then this tool and some valve grind paste to re seat them

http://www.minisport...OL660904SP.html

oh and a life save for anyone refiting valves and trying to fitt the fiddily little collets back to the valve stem use a bit of lm grease to stick the collets to the stem.

de coking the head isnt necisary as your car will run fine without but it will improve preformance and it was common back in the old days when the mini was around

[lrostoke]

Just to add a lot of instructions mention the gasket will say Top on it , tried all sorts and not had one yet that does.

Easiest way determine top is look at the gasket faces, one side will be flat the other will have rings where the opposite face bends over it. The side with the rings goes up.

Watch these

Edited by lrostoke, 28 April 2011 - 05:28 PM.

[jackog_mayfair]

Just to add a lot of instructions mention the gasket will say Top on it , tried all sorts and not had one yet that does.

Easiest way determine top is look at the gasket faces, one side will be flat the other will have rings where the opposite face bends over it. The side with the rings goes up.

Watch these

thanks for the videos! the head gasket that ive ordered and have now says top so thats ok

[jackog_mayfair]

take your time make sure both machined faces are clean and try and get any carbon or old gasket off.

and while your at it you could de coke the head.with the two outer pistons elivated i put a rag in the two lowerd pistons that are now siting down in the bores and cleaned up the raised pistons with fine wet and dry sand paper and a wire brush drill attatchment. then rock the car whilst in gear or spin the fan in neutral to get the two piston tops that were originilly recesed within the bores to lift to the top and do the same on them. you may want to re seat the valves where youl most likley need this tool

http://www.minisport...OL660210SP.html

to remove and replace them and then this tool and some valve grind paste to re seat them

http://www.minisport...OL660904SP.html

oh and a life save for anyone refiting valves and trying to fitt the fiddily little collets back to the valve stem use a bit of lm grease to stick the collets to the stem.

de coking the head isnt necisary as your car will run fine without but it will improve preformance and it was common back in the old days when the mini was around

thank you for the advise it really does help!

[Dan]

DO NOT clean the block and head faces with sandpaper!

[afhuey]

DO NOT clean the block and head faces with sandpaper!

^^^^^^
+1...DO NOT!

Get a gasket scraper and be sure to clean out your bores before you reinstall. I use a Shop Vac (w/a plastic nozzle) just before I install to ensure all the bits of crud are out from inbetween my pistons/rings and cylinder walls.