Head Gasket replacement

[Simon and Julia]

Think I know what to do..........but I would really appreciate an idiots guide to repalcing the head gasket on a '60 850, so I don't miss anything important!!
Thanks.

[mk1]

To remove the head;

Drain water, undo rocker cover, disconnect bypass hose, top hose & heater hose, remove inlet / exhaust manifold from head & exhaust pipe, put to one side. disconnect plug leads. Undo 4 1/2" nuts securing the front of the rocker gear, undo cylinder head nuts, starting in midle & working in a circular route round all 9 nuts. remove the rocker gear, remove the cylinder head.

Clean both the head face & the block face using a sharp scraper & pertol, when both surfaces are perfectly clean refit new head gasket ensuring the the lettering "FRONT" is up & near the radiator. Replace the bypass hose with a new one, replace rocker gear, do cylinder head nuts up to correct torque (this is crucial!!!!!) once again starting on the middle one at the front, then the two middle back ones, then the 2 front ones next to the middle one, continue to work outwards in this fashion until all nuts are torqued to the correct degree.

Replace all the other bits, re set the points and off you go.

Not exactly a full blow by blow account, but something like.

[medwaybeat]

And label / number the plug leads before you remove them

[guru_1071]

pertol

the beaks make handy scrapers....

[graham in aus]

Replace all the other bits, re set the points and off you go.

I think Mark meant to write: "Re set the Rocker arm clearances" you can use the rule of 9, number one down, check number 8 etc

Good description though Mark!

[graham in aus]

Oh and that's a Petrel Guru, not a pertol!



Is Mark getting annoyed yet?

[mk1]

I never get annoyed

And Graham is of course correct I meant re set the rocker gaps, not the points.

[999 ORX]

A handy tip/correct good way of cleaning up your faces of your head and block (on a cast iron face, and not on a alloy head) is to use a flat implement with some emery cloth wrapped round it .
I use a nice big flat file with a big long piece of emery cloth (never just use the file on the face thats not a good idea!) this way it ensures your removing muck evenly.
If you can get some brake cleaner its even better than "pertol" as it leaves the surface clean and grime free.. enjoy!

ps dont get brake cleaner down the bores!!! spray it on a cloth and wipe it.

[guru_1071]

Oh and that's a Petrel Guru, not a pertol!

g

you should never let minor spelling mistakes get in the way of a good sledging!

[Simon and Julia]

Well, thanks to the advice, I have now removed the head!! Excuse my excitement but this is a major event for me!
Although I generally go by the rule if it wasn't broke don't fix it..........the top of the pistons have a light covering of coke that is quite rough in places and the face of the block is generally in need of a good clean.
My questions are:
Can I gently clean the top of the pistons, is it worth it?
Best to use to clean the block? Petrol? What if it gets in the coolant holes??

Hope that makes sense....any other wise words (relevant or otherwise!) greatly accepted.

[Smiffy]

If it's a standard set up ie. the original combined exhaust/inlet manifold, it's easier to split the down pipe off and take the manifold off with the head.

[Simon and Julia]

I have torqued the head bolts correctly at 40 lbs/ft. I have replaced two studs only as the others were stuck solid. I am getting water leaking up from two of the head nuts now. Should I re torque to 50? Haynes seems to vary.
Regards.