tired of looking tdc arrow!!!

[Lee Pape]

Because it was explained on the old Mother Board years ago that with the looser valve clearances on the 750's it was possible to set the valves too tight using the twirl method. If the valves are too tight you may burn a valve or a valve seat.

[Mr Wazzock]

Must not assume that because the pushrods are free to rotate, that the gap will be correct, or will be set correctly if required, getting the TDC mark in the window will make absolutely sure.

By the sounds of because the 650 gaps are so small, then if both rods are free to rotate then must be near as dammit at TDC. Personally I'm not convinced that that is good enough, but never mind.

.

[hotflash44]

No way did i mean that if the push rod spins the gap is correct, that's a shot in the dark method, what i did say was if the push rods are loose ,not in anyway applying pressure to the rocker, that the valve is totally closed. It has to be because the spring is pulling the valve closed. That being said it is time to make the correct adjustment. Cant see how the gap size, or 650 or 750 effects the adjustment procedure. Thanks Guys a lively discussion, if you feel im a lost cause just sign off as im probably to dense to understand. no biggie!

[Abaxter593]

No way did i mean that if the push rod spins the gap is correct, that's a shot in the dark method, what i did say was if the push rods are loose ,not in anyway applying pressure to the rocker, that the valve is totally closed. It has to be because the spring is pulling the valve closed. That being said it is time to make the correct adjustment. Cant see how the gap size, or 650 or 750 effects the adjustment procedure. Thanks Guys a lively discussion, if you feel im a lost cause just sign off as im probably to dense to understand. no biggie!

No one cares.

Sometimes it's easy to get confused, over the simple things.

We've all been there.

[BillyG]

You guys don’t explain things well and muddy the waters. The “Spin Method” was a way to set the valve gap on the older 650 engines where the gap was very tight at around .002. You adjusted valve when on TDC for that cylinder, so you could just spin the pushrod freely with no binding. From tight to just free spinning. Didn’t need a feeler gauges.

Checking if you are on the correct cylinder to adjust by spinning the push rods is different. As mentioned above, when on TDC, one cylinders push rods will spin whilst the opposing cylinders rods won’t. If the push rods on the cylinder you are adjusting won’t spin...rotate engine TDC mark around one turn and push rods will spin. Maybe.

Easy peasy.