Tappets - Help, Run out of adjustment

[markevo30]

I've just been setting the tappets after a top end strip down and everything was going well until the very last tappet. On no. 4 i've wound out the screw as far it will go and there's no gap at all, let alone for the feeler gauge.

I loosened the rocker assembly and as soon as i did a gap appeared so it's not far off.

Has anyone else come across this before? What can be wrong?

 

[Tofufi]

Are you sure the engine is in the right place in its rotation?

If you're 100% sure it is, that's not good news...

 

[markevo30]

Yes I'm sure.

I've just spun the engine round so the inlet valve is compressed and the exhaust valve is fully closed and there is a small gap, about 0.05mm.

Bit of a head scratcher.


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[Moseley]

Could be an indication that the valve is about to snap if it has stretched that much. Have you tried turning the crank 360 degrees and checking the gap again?

 

[paul_q]

If you have swivel foot rockers make sure it's on the flat surface.

 

[markevo30]

I've taken off the rocker assembly and had a look to see if the valve seems to have stretched. It looks ok to me. I'd have thought you'd be able to see it sticking out a bit.

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[Happystamps]

Does the pushrod move when you rotate the engine?

Are you 100% that the pushrod is correctly seated?

 

[markevo30]

Does the pushrod move when you rotate the engine?

Are you 100% that the pushrod is correctly seated?

Yes the pushrod moves as it should and its seated right too. I've had a play with it.

I think I'm going to have to strip the head off and get the valve out to measure it to see if it has stretched. I've ordered a spring compressor of fleabay.

A couple of other thoughts though before I do that.
Should there be any gaskets between the barrel and the head? If there was it would give me a bit more room to play with.

There seems to be some spacing (square washers) beneath the rocker assembly (see photo). Does it look right?

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[Graham L]

Yes I'm sure.

I've just spun the engine round so the inlet valve is compressed and the exhaust valve is fully closed and there is a small gap, about 0.05mm.

Bit of a head scratcher.


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Thats not really the way to set them up, did you start at TDC on number 1 cylinder as thats where you start from, not when the inlet valve is compressed as you set the inlet and exhaust at the same time on each cylinder. Starting at number 1 and then rotating the engine counterclockwise 180 degrees and set number 2 and so on.

 

[markevo30]

Yes I'm sure.

I've just spun the engine round so the inlet valve is compressed and the exhaust valve is fully closed and there is a small gap, about 0.05mm.

Bit of a head scratcher.


Sent from my iPhone using Tapatalk

Thats not really the way to set them up, did you start at TDC on number 1 cylinder as thats where you start from, not when the inlet valve is compressed as you set the inlet and exhaust at the same time on each cylinder. Starting at number 1 and then rotating the engine counterclockwise 180 degrees and set number 2 and so on.

Thanks Graham, but i did set them in the correct order of 1,2,3,4. I just spun the engine to see if there was a gap at any point of the engine's rotation when i was trying to figure out what was going on.

I've just been doing a load of reading up on the samba whilst at work :msn4: and i think i know what the problem is. Something i didn't realise i had fitted were ball foot adjusting screws (i'm no engine expert). It seems that as well as fitting the rocker shims provided with these aftermarket adjusters you may have to grind a bit of the rocker to allow for the adjuster to be wound back further. If you read into it more it can all get very complicated trying to reset the rocker geometry back to factory to avoid wear on the valve guides. This seems to involve a combination of fitting the shims, grinding the rockers and shortening/lengthening of the push rods. As i'm running a stock motor i'm just going to fit some standard adjuster screws and see what happens.

Thanks for everyone's input on this, i'll hopefully come back with some good news when i get the stock screws.