timming trouble

[peter e mark]

Hello engine tune up experts, and todays question is : For my M37, How do set the timming when the damper pulley has no apparent markings or indicators ? Looking at the picture in the TM Johnny B sold me, I see in the pictuire the damper surface, the forward most edge of the damper itself, where I assume the timming value indentations are supposed to be, and then the stationery pointed marker. The picture shows about an inch of space between the very tip of the stationary pointer, and the edge of the damper, where I would expect to be able to raed 2* atdc. But on my engine, this pointer is well foreward of the edge of the damper. covering the visible damper surface as it turns under this pointer. And I manually turned the engine 360* and could find no markings on the damper edge anyway. Attaching my new bought timming adaptor, I energized my timming light anyay, and don't recognize anything by which to adjust? Am I looking in the wrong area for these markings?

[M-Thrax]

Its not a dampner its a pulley ( 230's are internally balanced ) anyway there were quite a few 37's that did not have the timing marks stamped on pullies enough of them to have the TM's show a drawing on how to find/mark tdc on these stampless pullies. I can fax you the print or you can find a pully with the marks or you can do what I did on both my 230 engines ( WC-21 & M-37 ) and that was to set the timing using a vacuum gage.

P.S. double check your pully, the marks are on the inner lip of the pully, could be buried under paint.

P.S.S You can also find tdc by pulling the little 1/8" plug on the head right over #6 piston, when #1 cyl is on tdc of the compression stroke #6 will be at tdc of its exhaust stroke, thats how the factory did it.

[JBizal]

I have NOS pulleys with the timing marks on them in anyone needs them.
John
www.midwestmil.com

[peter e mark]

M-Thrax...Goddamn that's alot of options. Thank You. So when you say the markings may be on the inner lip of the pulley, that means i will use a mirror, or maybe i can see it from the underneath. I will look . My fax number is 212-534-9654. Please use a cover sheet entitled "peter mark" If all else fails I can change the pulley, right? (That means another call to Big John)...M-Thrax, Are you going to Aberdeen? I would like to meet you there.

[M-Thrax]

No No
On outside top of inner flange of the pully ( if that made any sense ). I'll fax that print to you now.The military changed the timing to 2°BTDC in 1956 but I found 4°BTDC as optimum for my 230's but this can vary with altitude, mine was at sea level ( Florida). If you do it with a vacuum gage 17-21"of steady vacumm is good but the closer to 21" the better ( keep the idle under 600rpm when setting)

[pfrederi]

I thought my engine didn't have the marks either. Using the wire in the #6 access hole trick get to TDC then put some paint remover on the pulley to both sides of the pointer...let it sit scrape it off and I bet you will find marks.

Many of the motors in our trucks were overhauled during their lifetime and probably had unmarked pulleys replaced during the rebuild.

[peter e mark]

Sounds good pennsylvania, And I 'll certainly try it.