Timing questons b85 57

"All I've got is this Selo

"All I've got is this Seloc book, and it doesn't show anything useful for this. The attachment is a representation of my timing pointer. I can see no numbers on it from where my head fits.
Is it;
small v to right=5*ATDC
Large V in center=TDC
small v to left=5*BTDC
leftmost small v=10*BTDC

???
I've got it set at idle to the leftmost v thinking that's 10*, as the book says. If I can figure out for sure what mark is what I can reach it with a black marker to put something readable on there.
pic

"They usually had a stamp on e

"They usually had a stamp on each point, but it often got rusted over. So hit it with a wire wheel on a drill and see if you can find those stamps.

Next step is a timing light with a dial on the back."

"There is no getting to it, th

"There is no getting to it, that's why I'm asking here. I'd think that any other mid '80's OMC 260 has the same indicator, so it should be easy if you can read yours.
There's also no rust, just the factory blue paint that doesn't lend itself to reading from 4 feet away."

"Feel your pain, but If I had

"Feel your pain, but If I had one to read I'd be on the colorado river with all the other amateurs.

Any way- I would run it at 7 degrees and listen for ping on the first trip and if the ping shows up would kick it back till it goes away."

"Maybe someone who [i]owns[/i]

"Maybe someone who owns an OMC 260, and can read thiers, can tell me what it says.

Or it may just be easier to tear the front of the engine compartment out of my boat."

"This can be made real simple

"This can be made real simple if you were to purchase degree tape from an automotive parts supplier.... (probably $8)
You will need to know the diameter of your harmonic balancer in order to get the correct tape (decal).

Clean the balancer surface.... apply decal according to the instructions.

Now you have the ability to use the degrees on the decal against the largest V in the tab (of which zero to zero should be TDC).

This allows us to set not only BASE advance, but to also check/set TAT (total advance timing) of which is actually much more critical for a marine SBC.
All of us should be checking this anyway. Too many of us don't understand the importance of this for a marine gasser.

Use your OEM specs for this setting and for the RPM at which this reaches Full Out advance.
It you cannot achieve the specs, your distributor needs to be re-calibrated or replaced.

I do not recommend the use of the digitally advancing timing light mode for this.
You'll want to see this in Real Degrees, and in Real Time as you increase RPM, IMO.

Do this, and your engine ignition will be delivering a spark lead that will give it the best potential for the most power, yet not risk detonation.
Again, see your OEM specs for this.
."