Marks for M38A1 timing cover tab cont from previous thread

Headcase · Post by **Headcase** » Tue Jan 24, 2012 12:23 am

Warming up here so that means more rain..but... could always be worse right?
Any way i was under the hood where i am spending most of my time and saw that there is the tab that you show in you pics. It has the tow lines on it and is spot welded to the timing chain cover...I am not seeing any bolts to bolt it on. It has a smal fork on the end with two prongs and that small gap between the two prongs seems to be approx the middle of the two lines.
Are the tow lines tha same as the lines that one would fins stamped on the timing chain cover?

If so the then the first line would be 5BTDC and the second lin TDC correct?
What about this little gap and the fork then...?

I read the downloadable manual for this in the TM9-8014 and it lits the three ways to set the tining...thinking I'll go with the second way the timing light. just watned to know which line to try to set it to or the gap?

thanks again soon out from under the hood! ? Ha! H Case

chicklin · Post by **chicklin** » Tue Jan 24, 2012 12:18 pm

Was just doing this myself and I believe, yes, they are 5 btdc and 0. I think the little v-notch is just what resulted from them creating pointers for the two positions mentioned above. Set it to 5 degrees btdc and you'll be fine.

Post by **wesk** » Tue Jan 24, 2012 5:38 pm

With 87 octane gas you can push that static timing setting up a bit to about 7 BTDC. If you are mixing 100 Low Lead aviation gas with the 87 octane car gas then you can go to 9 or 10 BTDC.

Headcase · Post by **Headcase** » Tue Jan 24, 2012 7:51 pm

Thanks all will try this tomorrow and hope I will not need the wife to uncerimoniously tow me home...again

53a1 · Post by **53a1** » Wed Jan 25, 2012 6:13 pm

If you are mixing 100 Low Lead aviation gas with the 87 octane car gas then you can go to 9 or 10 BTDC.

Cool Wes. I'm going to give this a try. Will starting be a problem or should I just expect more HP

Personally I don't care about the HP and I'm more concerned with reliability.

Post by **wesk** » Wed Jan 25, 2012 10:36 pm

I've been mixing 100 Low Lead avgas with my mogas in my jeeps and tractors for well over 20 years and will do so for just as long as they keep making 100 Low Lead avgas.

If you mix 50/50 you end up about 90/95 octane and and about the same amount of lead that was in regular gas in the late 60's. Should start easier.