Timing Dimple

[mshmodela]

As a newbie, I was checking my engine timing per this Marco Tahtaras's method:

http://www.abarnyard.com/workshop/timing.htm

And found it tad difficult to detect the dimple, I suspect as Marco's paper point's
out my timing gear dimple is not as deep or large as to properly mate with the pin:





So, going to have to adjust the tip...

As I recall that some folks check the #1 piston directly for it's maximum from the spark plug hole, what might anyone use (Stiff wire or?) to check it?

Thank you,

[Big hammer]

I ground a bolt like the modified timing pin pictured and worked great!! I never have been positive about using timing pin, when turning over motor the modified bolt stopped the motor right on the mark!!

[mshmodela]

Originally Posted by Big hammer

I ground a bolt like the modified timing pin pictured and worked great!! I never have been positive about using timing pin, when turning over motor the modified bolt stopped the motor right on the mark!!

That's a clever idea and you're certain of having it centered in the hole without play --assuming the bolt size and thread match that of the timing pin. I guess I'll be off the hardware store for a bolt to grind...

Thanks

[johnbuckley]

Easiest way to check TDC .... get some soapy water and paint it around the Number 1 plug, slacken the plug off a bit, turn the engine and watch the bubble(s) expand as you approach TDC and as you get past it the bubbles start to shrink. If you're feeling particluarly conscientious you can also confirm you've got the correct spot with the timing pin and dimple.

[Slotblog]

When I was having trouble finding my timing dimple, a light and a mirror worked well for me. Never did use the pin, just centered the dimple in the hole visually and it worked great.

I took the number 1 plug out and could see the piston coming up to TDC, so I knew I was close or 180 degrees off. I think they call that a bilateral solution set... LOL.

[Tiny]

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I use a coat hanger to watch the piston come up. Take the plug out of number one insert a wire over the valves to the cylinder bore and turn slowly. When i get close I close my eyes and feel for the pin to rest in the dimple as I s l o w l y turn the crank. My timing gear doesn't have much of a dimple but if I close my eyes and do it by feel I get it every time.

[mshmodela]

Originally Posted by johnbuckley

Easiest way to check TDC .... get some soapy water and paint it around the Number 1 plug, slacken the plug off a bit, turn the engine and watch the bubble(s) expand as you approach TDC and as you get past it the bubbles start to shrink. If you're feeling particluarly conscientious you can also confirm you've got the correct spot with the timing pin and dimple.

Ah another clever trick... out with my Mrs. Grabed a1" x 3/8 bolt for a new timing pin.

[Jim/GA]

Originally Posted by mshmodela

As I recall that some folks check the #1 piston directly for it's maximum from the spark plug hole, what might anyone use (Stiff wire or?) to check it?

I use a wooden chopstick that I insert through the #1 sparkplug hole, on top of the piston. It is easy to feel when the piston is at the top. You also need to look with a light at the valves to make sure they are both closed. Then you know you are on a compression stroke. I use one of those bent wrenches that goes on the crank nut, so I can move the crank forward and back until the piston is right at the top center.

I keep a small stack of those disposable chopsticks in the shop. They are handy for all kinds of things.

[Patrick L.]

Originally Posted by mshmodela

As a newbie, I was checking my engine timing per this Marco Tahtaras's method:

http://www.abarnyard.com/workshop/timing.htm

And found it tad difficult to detect the dimple, I suspect as Marco's paper point's
out my timing gear dimple is not as deep or large as to properly mate with the pin:





So, going to have to adjust the tip...

As I recall that some folks check the #1 piston directly for it's maximum from the spark plug hole, what might anyone use (Stiff wire or?) to check it?

Thank you,

What happened to that gear ? It looks cross-eyed with those 2 holes/dimples in it.

[CWilson]

Originally Posted by Patrick L.

What happened to that gear ? It looks cross-eyed with those 2 holes/dimples in it.

I see only one. I think maybe shadows.

[Walt Dupont--Me.]

Well, everybody is talking about timing. Every A-B I build, before I put the head on I get TDC on no. one piston, then I make a nice stiff pointer and bolt it to the cover and file a notch in the pulley and put a dob of white paint on the notch and pointer, now I can use a timing light when it's running or set the timing with a test light. On the B engine I just built, I put 2 notch on the pulley, One is TDC for the A dist and another the other one is 19* BTC for the B dist. BTW, the mechanical weights in the B dist only advance 8* that is why the B engines are timed on 19* I really like the A dist better than the B dist, I like to set a street light and retard the spark like an A, The A dist will advance 29* with the lever on the steering wheel. Of course if you a have a 32-33-34 you don't have spark lever. I've seen more than one A or B engine with the wrong timing cover, thay never have the timing set right. Walt

[Bruce,Upstate NY]

I use a nail that lives in a small hole in the cross member.

[30ccpickup]

Pull your plugs and it will take away the compression which will make hand cranking and finding the hole in the timing gear easier. Once you know what you are feeling for it will be easier next time.

A short stuby Phillips screw driver can be used to help find the dimple.

[hardtimes]

Originally Posted by Walt Dupont--Me.

Well, everybody is talking about timing. Every A-B I build, before I put the head on I get TDC on no. one piston, then I make a nice stiff pointer and bolt it to the cover and file a notch in the pulley and put a dob of white paint on the notch and pointer, now I can use a timing light when it's running or set the timing with a test light. On the B engine I just built, I put 2 notch on the pulley, One is TDC for the A dist and another the other one is 19* BTC for the B dist. BTW, the mechanical weights in the B dist only advance 8* that is why the B engines are timed on 19* I really like the A dist better than the B dist, I like to set a street light and retard the spark like an A, The A dist will advance 29* with the lever on the steering wheel. Of course if you a have a 32-33-34 you don't have spark lever. I've seen more than one A or B engine with the wrong timing cover, thay never have the timing set right. Walt

Hey Walt,
Excellent info / advice ! This is the way that I do this also. Nothing like a timing light to tell you what the engine is doing, eh!

BtW...One other thing to consider , besides people changing out A/B cam covers which may confuse. Also, be aware that these years, there are LOTS of guys who have changed out the old fiber cam gear for newer longer lasting metal cam gears. I've done this and have found that some of the metal gears DO NOT have adequate 'dimple' to detect with pointer. So, when installing these , now is the time to take notice and correct the situation by making that DIMPLE deep/large enough to detect. That is , if you do not like timing light process , as Walt describes.

[glenn in camino]

I always drill the dimple a little deeper.

[Mike V. Florida]

Originally Posted by hardtimes

Also, be aware that these years, there are LOTS of guys who have changed out the old fiber cam gear for newer longer lasting metal cam gears. I've done this and have found that some of the metal gears DO NOT have adequate 'dimple' to detect with pointer. So, when installing these , now is the time to take notice and correct the situation by making that DIMPLE deep/large enough to detect. That is , if you do not like timing light process , as Walt describes.

Great advice.