SV Series Timing Mark Variation

Thanks for putting up the stuff carl! I was gonna ask ya if ya still had the pics regarding your findings from a year ago!

Also...another confusing issue, maybe you can explain this based on your experience in dealing with IH parts at books:

as May be seen in the shots, the p/n suffix is all that appears on the actual part for id. And of course, that is a real advantage for identification.

But...the parts lists for the various drive gear applications show service part numbers to carry the "r91" and "r92" suffixs.

Are the "r1" and r2" suffixs to denote oem part, and the "r91" and "r92" suffixs to denote a service part?

Also...I have several "price lists" which were current in the 1981>1985 time frame for all parts from all IH divisions. And neither of the cam drive gear p/ns show in the price list under either variation. And nothing in the supercession data either. I simply can't see those parts going into the "obsolete" column when the motors continued in production up through the mid-80's.

Robert...I've yet to run across an "r3" or "r93" gear set. But Jeff mentioned that he has seen 'em. He might have a set in some of his used stuff, but I failed to sort through those when I visited ihon last month. There were some gears I found inna box though, maybe he can get zaed to dig through 'em and look for the r3 set! Put that boy onna mission and he don't give up if ya tell him a dollar is involved, he'll make an r3 gear set!

Based upon a previous discussion I had about this with Jeff a few years ago, we "thought" the "r3" (or r93?) gears would have appeared maybe around the late '77 time frame for the "next tier" emissions motor apps represented in the '78>'80 Scout II platform. But again, the Scout parts list for that point in time (mt 130 published oct./1980) does not show an r3 or r93 gear set p/n, it does show the r92 set as a service part.

So again...based upon what we know right now Robert...the fact that the aftermarket replacement gear set is all we can currently obtain new when needed, I'd say all our figgerin', bs'n, and calcs should be done with that set as a constant.

Regarding the lack of documentation and anomalies regarding tim's motor build from ***(my edit), I continue to get bits and pieces of similar "issues" trickled in from various sources who have experienced the same or similar. Seems the output of that operation can be a bit "erratic" at times and has been for many years! We got lots of lurkers watching this thread which has stimulated their own concerns!
 
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Mike,

I'll see what I can dig up. I remember the year before last at Binder Bee we included a booklet on decoding IH part numbers, or something along those lines. I'll have to see if I still have a copy or Dad does. You May want to dig through the Binder Bee stuff, as you might have one and not know it. I am fairly sure it was the year Mike roth was chair, so 07.
 
I've been looking for that booklet that was included in the bee registration package for three days now!!!! I gotta find a copy!

Since I have most (maybe all??) of the bee production archives here now, I've been through every box and file and can't find that booklet, not even my own copy from the bee! I know I put it away for reference purposes but ya know how I am about filing stuff so carefully until I can't find my own shit!

Now you have called me on this...I was too embarrassed to say anything so I just played dumb, not hard for me to do! The bee dude should have anything bee-related! In 20 more years, all this beecrap will be collectible too!
 
Found it carl!

It was filed with my 2005 Binder Bee registration packet!

Looks to be publication # 1 008 319 r3. Now I need to find the copy of the IH publication index I have and see if that doc is listed!

Lemme review this booklet regarding p/n decode and see what I can see!

On the last page of this item is one of those famous "IH cartoons"...it states "now put me where you can find me"!!!

On the bottom is the statement..."keep this booklet-it has holes punched to fit two rings of a standard size three ring binder."!
 
This entire part numbering deal is very complicated if you go back into history. But in dealing with what we deal in (for the most part), the numbering system we are most familiar with dates from a corporate changeover begun in 1944.

The "r1" and "c1" numbers denote a single part, that was introduced after the changeover in '44. If that part is always a component of an assembly (such as the cam drive gear set) and is only available as an assembly.

If the part number contains two digits after the "r" or "c" place holder, then the part number indicates an assembly that does not offer individual components.

Any digit in the r or c suffix other than "1" indicates a revision to the part which allows it to "backfit", but the "1" digit part will not fit applications moving forward from that point.

So in the case of the cam drive gear set, we see an individual part number on the cam gear, and the parts list denotes it is marketed only as an "assembly" including the crank gear. And the digit "2" (or the digit "3" that we are also looking for) indicates subsequent "development" of the assembly, in this case the tooth angle was changed to change the thrust direction. But the r92 gears will backfit to earlier applications as a set!

We'll investigate the suitability of making this document available in some form without stepping into any copyright issues with our Scout/light line family!

For those of you who have actual copies of an IH-produced parts list, there is a tremendous amount of information contained in the front of those volumes regarding serial number/vin decode, part number decode, production data decode, etc.

Regarding the part number assigned to the aftermarket cam gear set referenced previously, that number was developed by the original vendor for the aftermarket replacement parts. And that number has been carried forward over the years including additional prefix and suffix to denote the "re-seller" of that part. At this point in time, that gear set is manufactured in the u.s. And is available from several "brand name" sources, but the actual part(s) are only manufactured in the root by a single source.
 
So according to IH the r91 and r92 are exactly the same. Then why do so many complain of cam timing problems. Carl's findings seem to point that way.

I question if the cam timing issues we hear about are simply a dumb a$$ move on the builders part. Like mixing a gear into a (matched as they are) set that is not native to the mating gear.

The gear sets have a set designator stamped on them for that reason.


Rk
 
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I looked up cam timing when I got home. Only one valve event timing is listed for the sv 304 and 345. Michael only finds one cam grind listed in his books. When you look at that, what others have seen and the fact that IH lists the r92 and r93 timing sets as being direct replacements for the r91, maybe the gear mix up posibility is more likely.

I won't build the fixture but I will tear down the 152 I have and use that as the test insturment. I need to get into it for another deal I want to work on.

When I get the parts mm is sending me I will have a project for this week end.

Robert
 
Robert kenney said:
so according to IH the r91 and r92 are exactly the same. Then why do so many complain of cam timing problems. Carl's findings seem to point that way.

I question if the cam timing issues we hear about are simply a dumb a$$ move on the builders part. Like mixing a gear into a (matched as they are) set that is not native to the mating gear.

The gear sets have a set designator stamped on them for that reason.


Rk
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It could be when the cams are ground, the maker doesn't know IH used timing gear and grinds them to be used with a chain. He would grind in the pattern a slight offset so, when the chain wore in the timing wouldn't be off.

I degreed in the cam when I installed it and it was right were it should be according to the isky specs.
 
carl wiese said:
it could be when the cams are ground, the maker doesn't know IH used timing gear and grinds them to be used with a chain. He would grind in the pattern a slight offset so, when the chain wore in the timing wouldn't be off.

I degreed in the cam when I installed it and it was right were it should be according to the isky specs.
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That is a good point!!
I have had conversations with the bigger grinders about IH stuff. Like lobe angles to induce rotation, lifter bore clearances etc. Many say "oh they aren't like a Chevy?" :mad5: :icon_eek:

I think that as long you degree the cam you are ok. Did you have to tweek the cam timing or did it fall right on the cam card #?

My r91 ts was replaced with a r92 ts and timed on the cam card from schneider.

I hope to verify the timing sets so we will know and have something to tell people and back it up with data. The builder should still always gdegree the cam but atleast we can

timing chain compensation would be a very small (2 degree) advance ground into the cam. While the problems people have been having have been characteristic on a retarded cam.

Comp cams actually advances the cam grinds 4* because they feel people habitually buy cams that are to big for their application. This is from a conversation I had with one of the bw's at comp.

Robert
 
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Robert kenney said:
I think that as long you degree the cam you are ok. Did you have to tweek the cam timing or did it fall right on the cam card #?
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I don't remember, but I know we didn't have to mess with it after we intalled it to the stock IH timing marks. I'll look into my paper work and see if I still have the scratch paper we were using that day. I should also have the isky timing card if you want it.
 
Carl,
would like to know what the cam specs are and what you think about it eg power band/ low end torque.

We can add it to the "feels like" list so people can see how others like there cam choice.

If you find the card it would be great if you could post a picture.

Thanks,
Robert
 
Robert kenney said:
carl,
would like to know what the cam specs are and what you think about it eg power band/ low end torque.

We can add it to the "feels like" list so people can see how others like there cam choice.

If you find the card it would be great if you could post a picture.

Thanks,
Robert
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Sorry it took so long, but here is the isky timing card that came with my cam.
 

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Robert kenney said:
thanks carl,
how do you like it? How is the low end compared to the stocker?
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Lol, I haven't been able to drive it!! I have been trouble shooting a vacuum/fuel supply problem that I just recently found linked to the gas tank being full of rust and ruining fuel pumps. So I am fixing that and we'll be off and running!! (fingers crossed and the proper animal sacrifice made)
 
I didn't realize that was your $100.00 truck.:crazy: I guess I need to pay more attention to the details.:gringrin:
hope the starz are aligned for ya.

Robert
 
The $100 pos will be ready to drive to the exhaust shop next weekend! Enuff is enuff!

The jerry can fuel storage system will make sure it goes down the road and gits tha hail outta pop's place! I can see a whole bank of jerrys rigged in tha bed with an aquarium gang valve system tying everything together. A true whitetrash fuel cell kinda deal.

But then...rockscout does have a fuel cell onboard since ya most likely will end up parting it anyway (or it can come live here in storage mode).
 
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