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400f not starting after tappet adjustment.


Doom64
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Hello, I adjusted the tappets today all were ok-ish apart from one which hardly moved so I adjusted that one so it moved, put it all back together and it won't start, it turns over and backfired but that's it.

Any help would be great.

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easy way is remove spark plug and both the inlet and exhaust tappet plugs use long piece of wire or thin screwdriver down plug hole turn engine over slowly watching the inlet valve open then close and then next time the piston returns to the top check the tappets of that cylinder and do the same right across all 4 cylinders as the only time the gap would be correct is on the compression stroke with both valves fully closed at tdc

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How do I make sure it's at the tdc?

Should be markings on the flywheel. You can always pop a long screwdriver down the spark plug hole to check. ;-)


Silly question: are you sure you put the HT leads back the right way round?


Edit: Beat me to it Steve! :-D

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Yep leads are on the right way.

And when Turning the engine over you can use the nut with the timing mark on to get tdc can't you?

And you have to make sure cylinder 2 and 3 are at tdc? because cyclinder 1 and 4 are at tdc at the same time.

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Please don't put a screwdriver down the hole .... never place anything metallic into the cylinder bore ... wood plastic yes metal noooo

Pistons may be at same position but camshaft will be at different points

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could I have buggered the timing up by doing the tappets?

Not ignition timing but valve timing yes .. if they are too tight (small) clearance then the valve will open too early and close later ...

So on its firing stage ( intake compression firing exhaust) of a 4 stroke the exhaust valve may be opening


And if too large then the valves will open later and close too soon .... causing compression at wrong time

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In case it hadn't been mentioned but I'm sure it has...


You didn't adjust them right.


Get your piston to top dead centre and adjust to within spec. It will start then.

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