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MG MGB Technical - valves set up

Iam back my with blown head gasket Mgb, i refit the new one tight as per spects to 6mn, and fit the carbs, water pipes etc...
next is i suppose adjust the head valves..never done. i got the feeler gauge and the guts to do..i appreciate help from the experts, step by step pls.
the sparks plugs are still out, the timming is ok.

This video tells you how.

Clifton Gordon

The video help a lot, the valves are done and engine is running again.
some guys says the valves should be adjusted when cold and some when hot...whats the best?

No bubbles in the coolant circuit ..for time being...i will take it for a spin today.
thanks again, i could not do this without your help.


Cold, it's not going to change while you are doing it. The only benefit to changing hot is in the winter when it keeps your fingers warm. Set to .015" thou or .38mm. I actually use a go of .014" and a no-go of .016". Use the 'rule of nine' which means that whenever a valve is fully down adjust its 'nines complement'. Basically this means that when 1 (the front) is fully down you adjust 8 (the back), when 2 is down you adjust 7, 3 down adjust 6, 4 down adjust 5, and so on. You don't need to adjust them in numerical order, just turn the engine in its normal direction and which ever valve goes down adjust its complement. Should only need two full turns of the engine. To turn the engine you can either use a 1 5/16" AF socket on the crankshaft pulley nut, or put the car into 3rd or 4th gear and nudge it along. However because of a quirk with my cam I find that the back three valves are still changing when their complement is fully down, so I turn the engine a bit one way or the other to find the maximum gap on those valves, and adjust them there. If you adjust hot it is .013", .33mm.
Paul Hunt 2

Took it for a ride, and its ok, but still overheats, the needle just goes past the N, and the engine feels a bit hot..when standing rise up to 3/4 of gauge..
i have to get a thermometer to compare..
i got new radiator,v belt , thermostate, head gasket, radiator cap, new alternator(bearings were shot to pieces)the water pump is ok, flush the engine coolant circuit, new spark plugs (running grey/whiteish)..

White-ish plugs sounds like the mixture could be weak, which will cause an engine to run hotter.

What year? What ambient temperature do you have? An MGB with electric fans will idle at around 3/4 on the gauge i.e. half-way between N and H as the fan kicks in and out. With mechanical fans it shouldn't idle that high unless the ambient is in the higher 20s, I'd have said. As you say you do need a thermometer to determine whether it *is* running hot or just showing hot.
Paul Hunt 2

Paul. its a 71 model with mecanical fan, about 20Ēc ambient temperature, i thought also by running weak it could rise the temp.i will feed in more juice and see.

Really you need to set them up correctly, not just richen them a bit and see what happens.
Paul Hunt 2

This thread was discussed between 04/10/2007 and 09/10/2007

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