Author Topic: Setting the tappets on new build  (Read 217 times)

Offline Superflash

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Setting the tappets on new build
« on: 24.01. 2021 02:52 »
So all the tappets are loose after fitting the rocker box. At some point I've rotated the motor just to see how things were going. Result is I've now lost track of where the timing gear alignment is. Please tell me I don't have to take off the inner timing cover to reset it all? Grief...... *problem* *problem*
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Offline Beeza

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Re: Setting the tappets on new build
« Reply #1 on: 24.01. 2021 03:16 »
Simple way is to get the right rockers rocking, one opening as the other is closing and set the left pot, and vise versa.
Ensure the push rods don’t come out of the rockers.

Offline Superflash

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Re: Setting the tappets on new build
« Reply #2 on: 24.01. 2021 03:21 »
Cheers. So I  just hope it's on the right TDC when setting the gear side tappets? Apparently you set them when the push rods are sitting on the base lobe on the cam.
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Online orabanda

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Re: Setting the tappets on new build
« Reply #3 on: 24.01. 2021 04:14 »
Start with , say, the inlet valves.
If you are going to adjust the inlet valve closest to you, rotate engine until the opposite (furthest from you) inlet valve is fully open (spring compressed). You can feel the top of the rocker; it's easy to detect the point when the rocker is at the very bottom (valve fully open). At this point the cam is on the base of its lobe for the valve you want to adjust, meaning there is no lift for the valve. Adjust the tappet.

Then rotate the engine and repeat the process; ensure the valve you have just adjusted is fully depressed, and then adjust the tappet of the opposite valve (because the cam lobe is not lifting the cam follower).
Then repeat this process for the exhaust valves.

Happy days.

Richard


Offline Superflash

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Re: Setting the tappets on new build
« Reply #4 on: 24.01. 2021 06:05 »
Problem is... all 4 valves are fully closed. I had backed off all 4 tappets when putting the rocker box on.  *sad2* . I suppose I have a 1 in 4 chance of the motor being on the right stroke when starting with the gear side inlet valve. Or.... I take off the inner timing cover to reset the dots.  :!
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Offline Beeza

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Re: Setting the tappets on new build
« Reply #5 on: 24.01. 2021 07:23 »
No need to take off the inner timing cover.
Screw the adjusters till they start to ride on and then lift the valves. And then both methods work well.
Again ensure the push rods are seated in the rockers positively, I cannot stress this enough.

After you have backed of the adjusters to the max, a push rod can easily slip out to the side of the rocker cup.

So after you have gone through all this, turn the motor through a few times and check that the adjusters are about even.
If you can, try and see/ensure  that the push rod ends are in their cups.

As per Orabanda, when one exhaust is at max open the the other side is at zero, and vise versa, also for inlets, hope this makes sense.

Offline Superflash

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Re: Setting the tappets on new build
« Reply #6 on: 24.01. 2021 07:37 »
Cool thanks. So I was worrying about nothing. Cheers
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Offline Beeza

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Re: Setting the tappets on new build
« Reply #7 on: 24.01. 2021 07:50 »
It is pretty easy and pretty basic, take your time and keep checking things,.
Best of luck mate.