Fitting head gaskets

tcm

...
Joined
11 Jan 2002
Messages
23,958
Location
Caribbean at the moment
Visit site
Re: eh?

bottom dead centre is always 180 crank degrees opposite from top dead centre, innit? - it doesn't matter what the other cylinders are doing, or even if there aren't any. So wiggo is right, imho?

With the cyl head on, you can't see the valve open or shut. But you can see the little pushrod come up, and then go down, halfway between is TDC near enough, so 180 degrees near enuf the other side it'll be properly shut and the valve clearance can be set with crank thereabouts - the clearance has to be accurate, the crank position can be anywhere nearish BDC cos the cam is circular at either side of BDC.

<hr width=100% size=1>
 

Wiggo

New member
Joined
10 Sep 2003
Messages
6,021
Location
In front of the bloody computer again
Visit site
Indeed. T'ain't nowt to do with the config - with the valve wide open, the piston's at the bottom of it's stroke. 180 degrees later, it's at the top, so the valve is fully closed. It probably closed a long way earlier, but that 180 makes sure of it...

<hr width=100% size=1><-- insert witty sig file here -->

<A target="_blank" HREF=http://www.fairlinetarga29.info>Buy my boat!</A>
 

Nauti Fox

Well-known member
Joined
28 Oct 2003
Messages
10,696
Location
Kent
www.facebook.com
Oops. work interfered for a short while.I think I'll stick to TDC with a brazing rod down the injector hole,pretty foolproof I hope!
Al.

<hr width=100% size=1>
 

Nauti Fox

Well-known member
Joined
28 Oct 2003
Messages
10,696
Location
Kent
www.facebook.com
Thanks for your help guys,now about lightening the heads, so I can actually lift the things without doing my marital prospects a damage................

<hr width=100% size=1>
 

BarryH

Active member
Joined
31 Oct 2001
Messages
6,936
Location
Surrey
Visit site
Angle Grinder!!...............apliance of science, best tool by far. Second only to the lump hammer.

<hr width=100% size=1>
captain.gif
 

ccscott49

Active member
Joined
7 Sep 2001
Messages
18,583
Visit site
Re: eh?

Quite right, brain in gear next time, before engaging fingers! But at bottom dead centre on the power stroke the exhaust valve is already openimg or in fact open, you need the piston at TDC on the power stroke for both valves to be closed completely. ie on the back of the cam.

<hr width=100% size=1>
 

OzGirl

New member
Joined
3 Dec 2003
Messages
38
Location
Oz(NSW)
Visit site
Back to the original question - certainly no sealant with copper/composite gaskets, but we've always smeared the mating surfaces with an ordinary motor grease before bolting down. G'day folks.

<hr width=100% size=1>
 
Top