New web page: Corrections?

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration
Model T Ford Forum: Forum 2015: New web page: Corrections?
Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Wednesday, July 22, 2015 - 01:15 pm:

The question of how to set timing comes up often, so I made a page about it. Do I need to add, subtract, or correct anything?

http://dauntlessgeezer.com/DG97.html


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Georgetown TX on Wednesday, July 22, 2015 - 01:27 pm:

The directions that you have given set the timing too early. The piston should not be at TDC when the coil buzzes. It sould be on the down stroke.

The piston has a certain amount of "dwell time" at TDC. In other words, the crankshaft turns a few degrees with no piston movement. This is why we always use an object such as a plastic coffee stir stick from McDonalds to feel when the piston actually moves downward.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Wednesday, July 22, 2015 - 02:11 pm:

Royce:

Why not use the pulley pin since it is EXACTLY horizontal when any piston is EXACTLY at Top Dead Center (TDC). If the pin is horizontal and your piston is not at TDC then your crankshaft is broken. Advancing the crank via the handcrank and stopping when you hear a coil buzz should result in the pulley pin being just past horizontal when the timing lever is fully up. I set all my cars that way and they all start easily and have never kicked back.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dan Treace, North FL on Wednesday, July 22, 2015 - 02:38 pm:

Steve

You should add:

Step 1. Move the Spark Lever to top of quadrant on steering column (Full Retard). Disconnect timer linkage......

That makes sure the lever is at full retard when setting the timing.

And you mentioned in Step 8... the timer case is rotated back so it stops buzzing. That is what is needed to be explained. Setting the timer to just buzz the coil at TDC can be problematical. The timing needs to be set for the coil to buzz just past TDC by about 10-12 degrees or so.

The crank pin should be at 3:15-9:15 as on a clock face. This is important too for electric starter Fords, to save the Bendix, that at full retard, the timer will allow the coil to fire at 10-15 degrees past TDC.



Degree tool confirms the timing at 15 degrees past TDC.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Wednesday, July 22, 2015 - 03:54 pm:

That's what I got when I used Royce's suggestion of a straw on top of the piston. When the straw moved, the pin was about halfway between 3 and 4 on the clock. My arithmetic calls that 15. Corrections made.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Patterson-Nicholasville, Kentucky on Wednesday, July 22, 2015 - 04:14 pm:

The crank pin method cited above, though correct, is difficult to accomplish on a later Model T car with the sheet metal valence over the crank handle hole. In those cases I recommend the tool shown.
Ron the Coilman


Top of pagePrevious messageNext messageBottom of page Link to this message  By Royce in Georgetown TX on Wednesday, July 22, 2015 - 04:22 pm:

John,

It is easier to use my method than to remove the crank to see the pulley pin. On two of my cars the crank is riveted to the pawl, not too easy to see the pin. Plus, I am not interested in the position of the pulley pin, I want to know about the piston position when the spark occurs. Are the reproduction cranks all going to have the pin hole in the right place? How about Model A cranks that get drilled in a machine shop somewhere, by somebody I don't know?

I am not happy unless I have hard facts. I don't want to depend on unknown variables that don't save me time anyway.

And if you have a 26 - 27 it's really hard as Ron points out.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry VanOoteghem - SE Michigan on Wednesday, July 22, 2015 - 04:56 pm:

Working in and with machine shops for almost 30 years, it has been amazing to me how a machinist can instantly come with at least 6 reasons why your idea will not work... but his will. Well, it's true, sometimes my ideas don't work... and there's do, but it's not like that's really even the point. It's the absolute & instantaneous resistance in the face of logic that I find interesting. I sometimes see that on this forum and always find it amusing. Mind you, I'm not saying any of you are wrong in your individual approaches. You just have the way that works best for you... the only way! Have fun guys.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Wednesday, July 22, 2015 - 05:59 pm:

I've never had to remove the crank to see the pin. On any T before 1924 it's easy to see.


I can see how the radiator apron on 1924 and later cars could be a problem. Then I'd stick a straw in the plug hole for sure.
:-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Wednesday, July 22, 2015 - 06:37 pm:

Royce you don't have to remove anything on most T's you just pull the hand crank back out of the pulley and look below the radiator into the pulley. I can measure the timing on your car while wearing a suit and tie and never have to do more than look under the bottom of the radiator into the pulley which is easy. Go take a look. Just pull the hand crank out of the pulley and look.

As for the crank pin hole not being in the right position - it is marked on the drawing as being angle 0.000 and is used to grind the crank throws when the crankshaft was made so if you don't believe it is right then I don't see how the crank can be right. If the Scat crank maker made his crank without at least looking at the Ford original crank drawing then I don't want a Scat crank. Why on earth would someone make something that complicated and expensive without buying the Ford drawing to confirm locations of things. I think they did look at it. I have not viewed the Model A crank drawing so can't say anything on that. I haven't seen a T yet that the pin method didn't work on but I suppose I could be wrong.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Wednesday, July 22, 2015 - 06:40 pm:

I should point out that I have heard nothing but praise for the Scat crank since I didn't mean to besmirch their quality. If my post came off that way it was not intended.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Charlie B actually in Toms River N.J. on Wednesday, July 22, 2015 - 07:11 pm:

RDC. Rocking Dead Center describes that small arc the crank throw passes through where there's no piston movement and you've got to get past that area because firing too soon could cause the crank to rock backwards. That's why you have to actually see piston's downward motion when setting the timing. It guarantees the piston will push the crank in the correct direction. It's also the reason that cranking with advanced timing will send you to see your brother-in-law doctor.


Posting is currently disabled in this topic. Contact your discussion moderator for more information.
Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration