Valve clearance

[airlifter]

I am adjusting the valves on the TR6 after I finally got the valve timing sorted out.(With a lot of help)

I don't have the book in front of me right now but it says to move the crank until two valves are open and check the clearance on another two. Would it not be just a easy to find TDC on #1 and mark the mark 120 degrees and 240 degrees on the damper to find TDC on the other cylinders and check each cylinder by the marks?

The first three would be the first in the firing order and the second thee marks would be the next three in the firing order.

Am I way off on this?

Thanks, Pete

 

[Andrew Mace]

What I've always found "easiest" to remember and to deal with is the "Rule of 13" ("Rule of 9" on a four-cylinder, of course). Think of the valve closest to the front of the car as #1 and the one closest to the rear of the car as #12. Check clearance on #1 when #12 is open, #2 when #11 is open, #3 when #10 is open, etc. -- the two valves always add up to 13 on a six (and 9 on a four).

 

[martx-5]

I've messed with the "Rule of 13", or the "Rule of 9" if a four banger, but I find it too easy to go astray and lose your place. I do like the idea of marking the crankshaft at 120° intervals. I marked my TRactor engine at 180° intervals, and it makes setting the valves a whole lot easier. Go for it.

 

[Andrew Mace]

I've messed with the "Rule of 13", or the "Rule of 9" if a four banger, but I find it too easy to go astray and lose your place....

I can sympathize with that, which is why I've been known to make sure I check each valve IN ORDER STARTING WITH #1, even if it means turning the engine several extra times! :thumbsup:

 

[TR3driver]

Would it not be just a easy to find TDC on #1 and mark the mark 120 degrees and 240 degrees on the damper to find TDC on the other cylinders and check each cylinder by the marks?

Problem is, you still have to look at which valves are open to know if that is TDC with #1 firing, or TDC with #6 firing. Then at 120 degrees, you need to know if #5 or #2 is firing, etc.

Generally I find it easier to work with turning the engine backwards, just because my driveway slopes away from the garage (so I turn the engine by leaving it in gear and pushing the car backwards). As each cylinder comes to the point where both valves for that cylinder are open, I set the both valves on the "opposite" cylinder. For me, the easy way to find the "opposite" cylinder is to trace the plug wire back to the distributor cap, then jump to the opposite side and follow that wire back to the plug.

But your method would work, as long as you keep the cylinder numbers straight.

 

[airlifter]

"Problem is, you still have to look at which valves are open to know if that is TDC with #1 firing, or TDC with #6 firing. Then at 120 degrees, you need to know if #5 or #2 is firing, etc."

I put #1 at TDC with #1 firing(Both valves closed) and set #1. When I turn the engine to the next mark I adjust the next cylinder in the firing order. I do this until all valves are adjusted. I just wondered if there was something different about these engines that would not let this work.

There must be a hundred ways of doing this and everybody will use the one that is more comfortable with them.

Thanks for all the feedback, Pete

 

[martx-5]

"Problem is, you still have to look at which valves are open to know if that is TDC with #1 firing, or TDC with #6 firing. Then at 120 degrees, you need to know if #5 or #2 is firing, etc."

That's real easy. If you have it a TDC, just look at the valves on the two cylinders whether six cylinder (#1 & #6), or four cylinder (#1 & #4). The cylinder with one of the valves open (exhaust I believe) is the one<span style="font-weight: bold"> not firing</span>, therefore the other cylinder is on compression.

Look closely at this animation. You can stop it with any cylinder at TDC, and see how the valves are opened or closed. Then just proceed to the next one in the firing order. You'll only have to go around two revolutions of the engine.

Every other method I've used always seems to require at lot more then two for one reason or another!

 

[TR3driver]

That's real easy. If you have it a TDC, just look at the valves on the two cylinders whether six cylinder (#1 & #6), or four cylinder (#1 & #4). The cylinder with one of the valves open (exhaust I believe) is the one<span style="font-weight: bold"> not firing</span>,

Or maybe not so easy :laugh:

If a cylinder is at TDC (each cylinder has it's own), then it should have either both valves partially open, or both valves fully closed.

My point was just that, with my method, you only have to watch the valves. Not the valves, plus the front pulley, plus the firing order (either forward or backward, depending on which way you turn the engine). On a TR3, the front pulley is kind of hard to see, especially if you are working outdoors in bright sunlight.