40 replies to this topic

[miniman5]

helo! just wonderign i am going to grind the valves in so ile need a valve spring compressor ile be abel to borrow one is this a fiderly job? seen the doing it on a harley on TV so its basicaly the same, what grinding paste should i use?

[Cir-clipalot]

Head gasket should be dry but check the heads straight before you replace otherwise youll be doing it all again in a couple of days.
Valve spring removal- piece o' p*ss just make sure you give the top of each stem a tap with a hammer as per haynes otherwise when you compress the spring the collets and top thing (sorry no good with technical names) will stick to the spring whereas it should stand proud allowing you to release the split collets.
good luck!

[Dan]

Only use fine paste. You don't want to be taking off too much metal, just enough to match the surfaces.

[miniman5]

so about half a pea's worth?


ohh another Q lol


in trhe gasket set the guy showed me and in the books there are 4 little rubber things what are they?

[TimS]

they are vealve stem seals, you put them on your inlet valves,t hey can also b placed on the exhuast valves but arent commonly used

[miniman5]

ohh ! i though they would be tiny little things lol, will the engien be loads beter than before once ive done it? at the momment it blows at the exhaust manifold and burns a little oil. will it respond better pull beter of what?


ohh abot uhe rockers, when i put them back on will i need to ajust them of not?? jsut plonk them on and bolt them up??

[Dan]

You need to use enough paste to do the job without using so much that it takes for ever to clean it out. Use a little to start with and if it's not working then add some more. Just a thin smear over the valve seat is enough. Just make sure you use fine paste.

Yes, you will need to re-adjust your rocker screws again after doing this.

And about what you said before, don't use any kind of sealant on your head or manifold gaskets. Always fit these dry.
A little blue sealant (non setting, don't use any kind of RTV or silicon which will dry solid) around the rocker box gasket faces helps to seal the cork to the metal, and you can use a little bit of the same on your thermostat and heater stub gaskets too if you like.
There are no gaskets under the rocker posts, and don't put any sealant under them. Make sure the rocker oil feed (which runs through one of the rocker posts) stays nice and clean, both in the head and in the post.
REMEMBER to keep your pushrods in the right order (keep them pushed into a cereal box with holes punched in it and numbered up 1 to 8), and any studs that might come out as you remove the nuts need to go back in the hole they came from.
The center front stud might be a little tight in the head, don't worry it's meant to be. It's also a head dowel to locate the head nicely.
As you take the valves apart it's VERY important to keep all the parts of each individual valve as a set and put them back in the position they came from. If you know anyone with a young child (I mean younger than yourself ) then get eight empty, clean baby food jars off them if you can. They are great for keeping the valve parts together. As you strip each valve put all the bits in a jar and number them 1 to 8 (1 is the water pump end). And then when you are regrinding only do one valve at a time and keep all the others in their jars.
You are only re-lapping your valves so don't go mental and I wouldn't bother with putting the grinding stick in a drill if I were you, it's very easy to remove load of metal if you do that.
While you have it apart, take out the temperature sender and give it a bit of a buff with some fine wet and dry sandpaper. ONLY take off the build up of crud on the surface, don't break through the copper. When it's nice and shiny you get a better reading from the gauge which is a good thing after you've changed the gasket, in case anything goes wrong and the temperature starts to climb when you restart it.

Hope that all helps!

[miniman5]

wicked thats anserd near all the questions! but raised a few more!


i didnt know the push rods would come out....


do they jsut drop back in?


hello again lol

how can i tell if the head is warped? and should i skimm it any way to raise the compression?

[miniman5]

hello just brought loadsa stuff! got a gasket set oil filter engien paint and a valve grinder suker thingi!


also lookign at the valve stem oil seals have a coil/spring type thing on one end, which way do they go in??

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[TimS]

the spring bit sits at the top, you will see the old ones when u take the valve springs off

[Leonard]

answering the question from falk, a thou is one thousanth of an inch. this is 0.4572mm

[Dan]

Lift the rods and give them a little twist and they will come out. You can feel them pop out of the oil in the tappet. Do it cautiously, one at a time and keep them in order. When you refit them make sure you get them seated into the tappets properly. Give them a twist again and you'll feel if they're in place. It's easy enough. If a tappet comes out of place don't worry, the 998 block has tappet chests that you can access to refit them properly.

To check if the head is flat you need a steel rule (in good condition). Hold the edge of it against the head and see if you can see light through under it or get a 1 thou feeler blade under it. Do it accross the front and back of the head gasket face sided to side, then do it front to back, do it between each cylinder, then diagonally each way to check how flat it is. If it doesn't need skimming then don't do it as it will rasie your compression ratio. It's easy to check and there should be a diagram or photo in Haynes to describe what to do.

[miniman5]

ok so dan when i lift the head of the rods will come with it?!?!?