IH Battery Ignition (distrubtor)

kopeck

Member
So every now and then I check eBay to see if there's a decent distributor on there for my A. There's always plenty of them but they're all listed as fitting everything from a A to a 400 (or what ever).

Correct me if I'm wrong but didn't IH distributors have different advances for different models?

I'm pretty sure I'm right, it's not like the old H4 that fit anything you could bolt it up to.

Maybe you can change the advance in them?

Thanks,

K
 
yes they do have diff. advance for diff. models. they all will bolt up to the diff. models also. diff. advance goes with a letter stamping on dist.just like the engine codes.
 
That's what I thought.

I wonder if there's a break down of what distributor goes with what engine/tractor?

K
 
actually there was a write up on dist's in the red power mag couple years ago and i think they mentioned some models.ooh now i wish i had that red power binder to keep issues in order, darn it.i'll try to find it when i get a chance.
 
(quoted from post at 08:53:44 11/05/12) actually there was a write up on dist's in the red power mag couple years ago and i think they mentioned some models.ooh now i wish i had that red power binder to keep issues in order, darn it.i'll try to find it when i get a chance.

That would be cool if you found it!

Obviously any of the A/B/BN distributors would work on my A but I wonder if the SA (C113), SA (C123) or any of it's kin would work too? The SA with the C113 ran at a higher RPM if I recall correctly but other then that was the same engine. The SA (C123) - 140 obviously are a bit different.

I wonder how many people blindly buy the wrong unit just because a seller on eBay says it will bolt up?

K
 
(quoted from post at 09:03:05 11/05/12)
(quoted from post at 08:53:44 11/05/12) actually there was a write up on dist's in the red power mag couple years ago and i think they mentioned some models.ooh now i wish i had that red power binder to keep issues in order, darn it.i'll try to find it when i get a chance.

That would be cool if you found it!

Obviously any of the A/B/BN distributors would work on my A but I wonder if the SA (C113), SA (C123) or any of it's kin would work too? The SA with the C113 ran at a higher RPM if I recall correctly but other then that was the same engine. The SA (C123) - 140 obviously are a bit different.

I wonder how many people blindly buy the wrong unit just because a seller on eBay says it will bolt up?

K

And also, how many of these old Farmalls got the incorrect distributor installed many, many years ago when they were converted from the original magneto?
 
Any "wrong" distributor will work on any tractor from the A thru the 450, EXCEPT the W9 gas and all gas-start diesels - these spin the opposite direction. However maximum power and fuel economy will suffer slightly unless the correct distributor is installed.

AFIK the various distributor timing curves are achieved by swapping springs in the centrifugal advance. So theoretically you should be able to get the correct curve for your A by installing the correct springs. However finding the right springs today may be a problem(!)
 
Yes the advances are different on some. Most of the letter series came with a 40 degree advance.
Lots of later tractors came with less advance. Also a lot of letter series distibutors got changed from 40 to 22 degrees when fire crater piston kits were installed.
Most of the distributors have a symbol letter that indicates what advance originaly came in them. Also a date code and serial number. That info is stamped into the round base where the two retaining clamps go. Usually unable to see the info unless the distributor is removed from the drive housing.
Most units with different advance or total rates have distributor shafts and or advance springs different.
Just today I checked out a distributor from a 350 gas. When apart I found rusted advance parts and a shaft with 16 degrees total advance. Should have had a 22 degree advance. Someone put a LP gas on it.
When I said letter series I was leaving the supers out. Lots of them were 30 degree total or less than 40.
Like Bob M said the diesels turned the opisite dirrection and only used 0 to 8 degree advance units.
If you like to tinker about any distributor can have the total advance changed by changing the hole size in the distributor shaft. Helps to have a distributor machine but with the right kind of timming light can be done on a tractor by trial and error. Easy if making the hole bigger for more advance and a little more work making them less.
 
Interesting.

I knew they would all bolt up, the bases are all the same and I knew they would all run but I wasn't sure how how much would be loss by throwing a unit from an M (for example) on my A. I have no idea if more advance is recommended for the C113 or less.

Kind of seems to me that any of the A-140 units would be close enough.

Really it's the curve that makes the difference more then what the final advance is set at right? I mean the H4 shoots straight to 30 deg no matter what the RPM is at, which works and had worked for many year but could be better hence the move to the battery ignition unit.

K
 
If I remember correct the 140 tractors used a lot lower total advance than a A. Original A and M tractors were the same.
I mess with bigger tractors the most, total advance does make a difference if you drop a plow in the ground and pull at or near maximin load all day and using the recomended fuel. Especially with higher compression pistons than original. Going to find pistons with tops eroded or the top edges eroded down to the ring grove.
Everybody does things different so I don't say much when I see the posts about setting the time by ear. I wonder what there doing with the tractor though. Especialy the 100 series up bigger tractors will sound like the time is retarded if set to specs.
Saw enough piston damage on them when worked hard to know what happens.
Toms post made me think of something else. IH furnished parts to change the advance on some mag equiped tractors when installing firecrater pistons.
 
I used to have the IH tuneup chart hanging on the
wall in the shop. It gave all the different dist
codes, total advance, rate of advance and part
numbers of the spring sets. One day we got in a
new tune up chart, parts dept tore down the old
one, put up the new, but it did not have all that
good information. Was more for later model
tractors. I managed to tape the old one back
together for the most part so it was still
legible. Never saw a tune up booklet with all that
good information. You can search and compare in
the parts manuals and eventually come up with the
right combinations but it takes a lot of looking.
I have filled the max advance hole and filed it
out on different occasions but , like said, trial
and error. Correct total advance is always the
most important for engine life. Curve makes it run
smooth at lower speeds and loads. The cap on
muffler should not be flapping back and forth when
the engine is sitting their idleing.
 
I want to thank you all for this info, it seems odd to me that there's so many variables here but you don't seem to hear it talked about much.

So here's another wrinkle, lets say an A was rebuilt with 3 1/8" stepped head pistons. Would it be better to go with a distributor off a later offset (100-140) with less advance or go for something more stock with more advance? Or is the reason the retarded the timing on the newer models more a function of RPM then cubic inches? I have done this, I'm more curious then anything.

As to why not just put an H4 on it? Well it has one, and I've got problems that seem like ignition. I have a BN with a distributor which was installed as an upgrade kit form IH back in the day (still have the manual). I just like the way the BN runs better (this is before the A had problems). I do a lot of mid throttle putting around, pulling carts and what have you, and the BN just plan run smoother.

K
 
Hey Kopek,

Something else I didn't see in the previous posts (may have overlooked it), but a mag goes to FULL advance as soon as the engine starts. 30, 35, 40 degrees advance on an engine at idle. Kinda makes one wonder how they would even run.

You mentioned a rebuilt C113 with step head pistons. Well here is my take on it from my experience. Rebuilt a 47 SA, originally had flattop pistons and a mag 35 or 40 deg impulse coupling. Overhauled it with fire craters. Ran OK at full throttle but at idle and mid speeds always had a slight miss.

Finally convinced Dad to spring for the IH dist conversion kit. Put it in with the proper advance plate (22 or 25 deg I think) for the fire craters (came with the IH OH kit) and it purred like a kitten.

So if you have step head pistons and a gas head, get a dist with a 20, 22, or 25 deg advance plate and it should solve your problems.
 
Thanks TractormanNC.

I haven't rebuilt the engine yet, it's just one of those things that I think I might do in the future. There's some gremlin in that engine and maybe going through it top to bottom would turn it up.

I'm thinking it's ignition at this point. The carb has been pretty much eliminated, I've switched out all the ignition stuff minus the mag it's self.

It's to bad that my SM and my A are fighting over my wallet right now!

K
 
Spark advance should always be tailored to the
compression ratio of an engine and speed it runs.
Normally you can do comparison to different models
like you said , newer models, and come up with
satisfactory performance. A 35 or 40 degree
advance was for a very low comp engine and when
you increase bore size that changes comp ratio as
you are squeezing more air into same size comb
chamber, then you put in dome pistons further
increasing it. Not a one size fits all. IH
actually made a special impulse coupler for the H4
magneto to accomadate fire crater pistons on the M
and H. Put one in for a guy who would not go to
battery ignitions, about 45-50 years ago.
 
BTW,ALL great info so far !!! Glad to see people have knowledge and are not "guessing" on here!

Something else you can do that is helpful.If you have a GOOD timing light with the adjustable avance knob on the back of it(Like a Penske)and you know FOR A FACT your front crank hub and your pointer are set at TRUE zero,you can set your engine at different RPMS ad actually see where your advance is coming in at and what your total advance actually is.

Like has been said below,The MORE compression and the MORE advance you add to the engine ,the MORE critical it becomes.

In a REAL seroius race engine,we can actually "burn them down" with too much advance(Yea,melting pistons!!! )
 
(quoted from post at 04:48:45 11/06/12) BTW,ALL great info so far !!! Glad to see people have knowledge and are not "guessing" on here!

Something else you can do that is helpful.If you have a GOOD timing light with the adjustable avance knob on the back of it(Like a Penske)and you know FOR A FACT your front crank hub and your pointer are set at TRUE zero,you can set your engine at different RPMS ad actually see where your advance is coming in at and what your total advance actually is.

Like has been said below,The MORE compression and the MORE advance you add to the engine ,the MORE critical it becomes.

In a REAL seroius race engine,we can actually "burn them down" with too much advance(Yea,melting pistons!!! )

What are these timing marks you speak of? :)

A/B/BN only have TDC marked on the fly wheel, there's nothing on the front pulley. You can of course check the advance, like you said with a timing light with adjustable advance. Just means you have to lie on your back to do it!

It still seems odd that there's no list floating around with a break down of what codes went with what tractors.

K
 
So just poking around TractorData...

The A & SA use the same engine specs, same bore & stroke, compression ratio and max RPM.

After that you move to the C123 in the 100 those few SAs with the c123. They all share the same bore & stroke, max RPM (1400 still) but the compression ration increases with each model. 100: 6.5:1, 130: 6.8:1, 140: 6.94:1. I'm guessing they did most of that with pistons & maybe head modifications.

So it kind of looks like anything off an A or SA would work no problems what so ever. If I wanted to rebuild the engine with 3 1/8" pistons a 100 distributor would be better, 3 1/8" stepped might even like the 140's setup, assuming they made changes in the advance between the 100 and 140. To check that I guess I would have to pour through the parts books.

I didn't look into the C/SC/200/230/240 line. With out looking I think they nursed a bite more HP out of those engines.

K
 
The article was in the July-August 2007 Red Power. Go back and read it. If you don't have a copy, the back issue is still available. There is a table with the article that lists the symbol, and advance degrees/rpm for every version I could find (37 of them).

The proper symbol for most tractors is given in the model's Parts Catalog. The Seviceman's Handbook "Engine Tune-up Specifications" lists the symbol(s) for each model built through the publication date, which was 1966.
 
I think you are correct on the article. I remember a fellow by the name of Jim Becker doing the article. Keep up the good work.
 
Yea,Kopeck I was speaking of My Super M,(It is marked on front hub)But it will work at the flywheel also ,if indexed correctly?)

The point I am making is you can "play around" with different advance curves and total advances and see if it helps you engine or not????
 
(quoted from post at 07:34:33 11/06/12) The article was in the July-August 2007 Red Power. Go back and read it. If you don't have a copy, the back issue is still available. There is a table with the article that lists the symbol, and advance degrees/rpm for every version I could find (37 of them).

The proper symbol for most tractors is given in the model's Parts Catalog. The Seviceman's Handbook "Engine Tune-up Specifications" lists the symbol(s) for each model built through the publication date, which was 1966.

Excellent!

I'll order a copy right away. Maybe I'll even use that as an excuse to order RPM....

K
 
(quoted from post at 12:26:06 11/06/12)
(quoted from post at 07:34:33 11/06/12) The article was in the July-August 2007 Red Power. Go back and read it. If you don't have a copy, the back issue is still available. There is a table with the article that lists the symbol, and advance degrees/rpm for every version I could find (37 of them).

The proper symbol for most tractors is given in the model's Parts Catalog. The Seviceman's Handbook "Engine Tune-up Specifications" lists the symbol(s) for each model built through the publication date, which was 1966.

Excellent!

I'll order a copy right away. Maybe I'll even use that as an excuse to order RPM....

K
Jim follows this forum. He may weigh in on this.
 

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