BD 264 timing ?'s

[masong]

So in my searching of this forum and a few other IH forums, I found some contradicting info or maybe I'm just thick headed...dont answer that one.


here goes:
Is the Big mark on flywheel (ball) TDC or 6 BDC


Should the engine be timed to fire on TDC or should it be 2-8 deg. before TDC as I have read both?

What are the other marks on my flywheel? I have 3 smaller marks that would be after TDC and 1 that would be before TDC.

Should the vacuum advance be disconnected during this process and if so, I should probably plug the vacuum port on the carb if I disconnect it there right?

How does one calculate deg. of advance w/ out the little marks on the flywheel housing that I am used too? I read Kovaleff's description of measuring the diameter of the flywheel and calculating the amount of degrees/inch of rotation at the circumference. But my flywheel is nicely encased in the flywheel housing and it seems a little extravagant to pull the tranny in order to set the timing.Smilie

Thanks for all your help and patience with me,

Mason

[Jim Grammer]

Is the Big mark on flywheel (ball) TDC or 6 BDC

IH has published descriptions of this that seem to conflict. I say use a hard stop in #1 cylinder if you really want to nail TDC, then mark the flywheel accordingly.

Should the engine be timed to fire on TDC or should it be 2-8 deg. before TDC as I have read both?

Few engines will run well with no initial lead. These engines are perfect candidates for 'timing by ear'.

Should the vacuum advance be disconnected during this process and if so, I should probably plug the vacuum port on the carb if I disconnect it there right?

Yes, both are good ideas, however chances are pretty good you're not going to get any vacuum signal to the advance unit at idle anyway.

How does one calculate deg. of advance w/ out the little marks on the flywheel housing that I am used too?

I just use a dial back timing light and don't worry about it :)

Back to the 'timing by ear'.... :D

[John Donnelly]

The best piece of advice I can offer you is this. The L-6 IHC engines have timing marks that are about as accurate as a hand grenade tossed into a chicken coop.

You need to power tune this engine to get it to run right, and the only way to do that is with a vacuum gauge.

Once you establish a real TDC with this engine, mark the harmonic balancer with TDC and put a Mr. Gasket timing tape on the balancer so you have an accurate way of measuring timing.

You will still probably find that this engine will run best with about 15 degrees initial timing with an advance curve that is full-in at about 2000 RPM's. Recurve your distributor if you have to.

Like the old chebbie 235, you will more than likely be faced with the fact that each tank of fuel will require a timing optimization from you unless you buy your fuel in the same grade at the same place every time. It is what I have discovered.

-John

[67IH1100]

I have just timed my BG 265 dont know if there the same but as john said the timing marks are not accurate I pulled number 1 plug and stuck a long srcewdiver in the hole and turned the motor over BY HAND untill it came up to the top but should add I coverd the hole with my finger and had a buddy turn it over untill it blew my finger off then did the step above then you know your on compression stroke when the screw drive comes all the way to the top turn it till it start to fall then back up then mark your timing an thats TDC and on mine I noticed I had to rmove the vacume from my advance and plug it at the carb I hope this helps.

[Jim Grammer]

I have just timed my BG 265 dont know if there the same but as john said the timing marks are not accurate I pulled number 1 plug and stuck a long srcewdiver in the hole and turned the motor over BY HAND untill it came up to the top but should add I coverd the hole with my finger and had a buddy turn it over untill it blew my finger off then did the step above then you know your on compression stroke when the screw drive comes all the way to the top turn it till it start to fall then back up then mark your timing an thats TDC and on mine I noticed I had to rmove the vacume from my advance and plug it at the carb I hope this helps.

Great way to approximate things. Folks should keep in mind that there is *very* little piston travel close to TDC, so with an 'eyeball' method you could easily be off as much as ±10°. That's why I(and most cam grinders) suggested the hard stop method. You can also rig a dial indicator, but most folks aren't set up for this and you can make a hard stop easily from a spark plug :)

[Doc Stewart]

Set points with feeler gauge, check with dwell meter. Advance timing by turning distributor. Advance until it pings under load, retard a bit until it doesn't ping at all.

Too high tech??

[Jim Grammer]

I say use a hard stop in #1 cylinder if you really want to nail TDC, then mark the flywheel accordingly.

Set points with feeler gauge, check with dwell meter. Advance timing by turning distributor. Advance until it pings under load, retard a bit until it doesn't ping at all.

Too high tech??

Teehee :)

Not at all....I meant *if* you really want to nail TDC :eek:

I certainly never have :D