Timing marks on crank pulley

[Dave F.]

Correct me if I Am wrong. While hand cranking the engine over to see the timing marks, the 1st mark to the pointer should be 16 degrees before tdc ? and the 2nd mark should be tdc. If this is correct where do I set my timing ? I've installed a Pertronx electronic ignition. And I want to use a timing light to to set timing Also do I set timing at 16*before tdc or top dead center? Thanks Dave F.

[coppersmythe]

i'm pretty sure you set the Idle timing at the first mark . dont take my advice alone . let the real experts come along . i've set mine with a timing light , and when idling up the rpm , the "mark " hardly moved . not sure what the second groove in the pully is for . coppersmythe..............

[tst]

yes, 1st mark is tdc and 2nd is 16, make sure the advance weights are free, lubed and working in the distibutor

[ricky racer]

yes, 1st mark is tdc and 2nd is 16, make sure the advance weights are free, lubed and working in the distibutor

Isn't that backwards? The first should be 16 degrees before TDC and the second one should be TDC. Correct me if I'm wrong....

[Eugene]

yes, 1st mark is tdc and 2nd is 16, make sure the advance weights are free, lubed and working in the distibutor

Isn't that backwards? The first should be 16 degrees before TDC and the second one should be TDC. Correct me if I'm wrong....

Yup. First mark to line up with the pointer is 16 degrees before TDC.

Initial engine timing, static time at TDC. Get the engine started and running well. Then you can either set the timing using fast idle,16 degrees before TDC, or at low idle at Zero degrees TDC.

Once timing is set, test at both low and high idle.

Evident slop and wear. I prefer to set the low idle timing just a thin, very thin hair after TDC.

[Glen]

Hi,
Below is a page from the Cub service manual, showing the timing marks.
I would time it at the TDC mark, when the engine is running at low idle speed, 500 RPM.
Then as you speed the engine up, the timing should advance up to the 16 degree mark, when the engine is at high speed, which is 1800 RPM for Cubs up to serial number 192113.

http://www.farmallcub.info/manuals/gss- ... 001-43.jpg

They are talking about other things on the page, the pic has the info with the timing marks.

[Dave F.]

I think the picture is wrong the 1st.mark as you crank to the pointer should be 16*btdc & the 2nd. mark should be tdc. the picture has it backwards. Dave F.

[tmays]

I think the picture is wrong the 1st.mark as you crank to the pointer should be 16*btdc & the 2nd. mark should be tdc. the picture has it backwards. Dave F.

Pic is correct

[Glen]

Hi,
The engine turns clockwise as viewed from the front, looking at the tractor.

The number 2 mark in the manual pic gets to the pointer first, it is the advanced mark.

A Cub hand crank will only turn the engine one direction, clockwise, as viewed from the front.

[coppersmythe]

my '48 only has one "mark" . would that be top dead center or the advance ? i'm guessing i time to it first and then adjust by "ear". (magneto) coppersmythe.................

[Jim Becker]

my '48 only has one "mark" . would that be top dead center or the advance ? i'm guessing i time to it first and then adjust by "ear". (magneto) coppersmythe.................

If the pulley only has one mark,it is TDC.
No, do not time first to the mark then by ear. Time it to the mark then leave it there.

[Glen]

Hi,
Below is a page from the 1949 Cub operator's manual, telling about timing a Cub with a magneto, if you need it.

http://farmallcub.com/rudi_cub/www.clea ... age-32.jpg

[coppersmythe]

Hi,
Below is a page from the 1949 Cub operator's manual, telling about timing a Cub with a magneto, if you need it.

http://farmallcub.com/rudi_cub/www.clea ... age-32.jpg

my '48 only has one "mark" . would that be top dead center or the advance ? i'm guessing i time to it first and then adjust by "ear". (magneto) coppersmythe.................

If the pulley only has one mark,it is TDC.
No, do not time first to the mark then by ear. Time it to the mark then leave it there.

thank you Jim for the info, i did not know the early cubs only had one mark . after reading the magneto instructions , i'm pretty sure i must have the governor gear off by a tooth . i painted the correct teeth and was careful installing it . But , when i crank the motor over the mag impulse snaps about 1 1/2 " past the timing mark . thanks again , coppersmythe...............