Discussion
Gee Boo said:
OR .... how do I search PistonHeads to find this subject ???
type .... pistonheads tvr classics essex valve clearances.... into Google search 
Or buy a copy of this ..... clicky here
It will also tell you the sequence to adjust them in.
plasticpig72 said:
For adjusting Tappets there is a very simple rule. Number of Cylinders times 2 +1.
So 6×2+1=13 magic number.
When 1 is open adjust 12(total 13)
When 4 is open adjust 9 (total 13)
And so on. If a four cylinder Engine magic number is 9.
Alan
Unfortunately this is not always true, Alan. So 6×2+1=13 magic number.
When 1 is open adjust 12(total 13)
When 4 is open adjust 9 (total 13)
And so on. If a four cylinder Engine magic number is 9.
Alan
The 'Number of valves + 1' rule only works if the valves are arranged consistantly eg E I E I E I E I .
On some engines (notably, 'Endura' versions of the Ford Kent ) they can be arranged symmetrically eg E I IE EI IE , where clearly this rule fails as some valves are 'the wrong way round'. So the valve to be adjusted is in the cylinder you've calculated, but not necessarily the valve you thought!
A more universal rule therefore is the 'overlap method'. If there is a cylinder where the valves are balanced at overlap (the exhaust valve is closing and the inlet valve is opening), then there will be another cylinder where the valves are both fully closed, and can now be adjusted. This cylinder is easily found by checking where both rockers rock (have clearance) simultaneously, as their followers are both on the back (base circle) of the cam.
plasticpig1972 said:
Thanks Twinkam,
never too old to learn.
I've always used that rule from my Apprentice days in HM Dockyard as Fitter and Turner.
I'm lucky i've never come across an Endura Ford Kent and didn't know they existed.
Cheers
Alan
No prob, it was what we all used 'back in the day' .. and engine design didn't really change that much until the 90s I guess. Thankfully there aren't too many engines that need valve clearance adjustment nowadays as most take care of themselves.never too old to learn.
I've always used that rule from my Apprentice days in HM Dockyard as Fitter and Turner.
I'm lucky i've never come across an Endura Ford Kent and didn't know they existed.
Cheers
Alan
The Fiesta and KA continued to use basically the Kent block but with a different head with siamesed ports (the cam was different, obviously!) until about 2008 I think. Come to think of it, the Cologne V6 engines had siamesed exhaust ports too (= exhaust valves are adjacent), so the rule of 13 wouldn't work on them either.
What Dockyard were you apprenticed at, Alan?
Edited by TwinKam on Tuesday 28th July 12:22
I had to adjust the clearances on a friend's V6 escort, after another friend had done them. Some were so tight there was no way the valves were closing, probably why one had a broken retainer, some so loose they rattled.
After everything was sorted, the engine sounded and drove so much better. A lucky escape.
After everything was sorted, the engine sounded and drove so much better. A lucky escape.
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