Gasket

Sorry my Englisch is not so good, i'm dutch.
I have to replace the head gasket of a OMC 4 cylinder sterndrive ( i think build 1970). The gasket is made from aluminium, do i need to add some liquid gasket too on both sides of the alu gasket. My friend tells that the seller told him to do so.. I think , it's asking for problems, you don't know how thick is is at some places and then create a leak.
second question: How do i adjust the valve lash. I saw a you-tube movie that you should lossen the nuts till the push-rodds can be turned, then fasten bij a halve turn.
Is this correct?.
third question: The carburator doesn't give any fuel when the motor is running stationair, the acceleration pump is working fine, but starting the engine is big problem, and it doen't run smoothly

The fire sequence is 1,3,4,2 isn't it?

Greet, Peter

Re: Gasket

Ok, the revision store said not to add liquid gasket, it's not good to do so. Now it seem that the head has been broken . The carburator isn't so simple, i found a document on the inet, i hope sombody transllate this.
Still not knowing what the fire sequence is

Re: Gasket

Most people use a newer composite type gasket (FelPro is one popular brand) . Gasket technology has come a long way since 1970.
Those original metal gaskets are not as forgiving. Most call for sealant both sides, but follow whatever instructions came with yours.
I like to verify lifter adjustments with a compression gauge. I usually set them with a compression gauge on a boat:
crank with a remote start tool, loosen until the rocker starts to rattle, tighten until compression drops off, split the difference.

this should help you out with specs and firing order etc.
http://www.4shared.com/file/102988421/c4f26d54/OMC_64-86.html

Re: Gasket

Thanks for your reply, it's very clear. The link you give is great: 572 pages, wow.
I've seen this movie on you-tube:
http://www.youtube.com/watch?v=QAlCVA5cCQM
but I never heard about a negative lash, as in the movie the valve's will be open? Or has this old machine a hydraulic pushrods.....
Any way, thanks, i've something to read.

Re: Gasket

Went back to 4shared, to find a manual for a yamaha 28A-653 (20 HP) , was my computer infected by a virus. So be carefull with that site