spark arrestor ??'s

[MelonKing]

Hello everyone, I have a few questions about the spark arrestor (?) that was on my cub when I bought it. First off, how were these set up from the factory? I've seen a verison with about a 2" long pipe from the manifold going to the arrestor and then a longer pipe coming out of the arrestor through the hood. Mine was set up with a longer pipe coming from the manifold up through the hood and the arrestor at the end with a weather cap on top of the arrestor, I was wondering which is the correct factory verison. Or is it neither?
Thanks again for letting me pick your brains... Dewight

[George Willer]

Probably neither, but anything is possible. Here's a theory... someone may have replaced the engine with one from a power unit. They had a different manifold that had 1 1/4" pipe threads especially to fit the spark arrestor. The '48 tractor had a 1" pipe thread as standard.

You can tell if my theory is correct by checking your engine serial number. If the engine is original to the tractor it's serial number would be slightly higher than the tractor's serial number and with the prefix of FCUBM. If a power unit engine the serial number would have a prefix of IMCUBM.

Here's the location of the serial number:
http://www.antique-tractor.com/CubFAQ/date-code.jpg

[johnbron]

Dewight, My arrester is like the first version you described in your post. I am talking about the arrester on my power-unit, I have never seen one on a Cub tractor.

[Jim Becker]

I don't think I have ever seen a factory installation on a tractor. Here is my guess:

More like your second description. I think the pipe between the manifold and arrester should be whatever length is required so that when it is screwed into the bottom of the arrestor, the overall length is the same as the pipe used without an arrestor. I think we have generally agreed that should be about 17".

[Patbretagne]

I was in Cognac France a week ago and saw 4 cubs, 1 french build and 3 lease lend american ones, the french was underslung and the others (in varying states of repair) had spark arrestors, not looking too closely but they all looked fairly original.

The American Cub that is/was at our local museum (no news at present) which was very very original had a spark arester (or however you spell it John*&²)
Perhaps for some obscure reason those that came over here had them. Sparks onboard the ship whilst loading and unloading???

I managed to get hold of one from this guy's scrap pile whilst I was there. "Just to have one around"!
Best wishes for Christmas and New year,
Pat & Noëlle

PS Yes you are right she was born on 25th December!

['Country' Elliott]

Like George & Jim...I have never seen a factory-installed spark arrester on a Cub tractor ...just on a very few power units. However, in Pat's 3 cases they may have very well been factory installed or special factory ordered for a specific purpose? For the most part, spark arrestors were offered by International for LARGER letter series tractors ( H, M, & W's) that were working in harvesting dry products (Corn, Wheat, etc.).

[MelonKing]

Well, you guys got me thinking so I went out to the garage tonight. The serial# on the engine is FCUBM 54709 (could be a 1 instead of a 7, hard to make out right now). My Cubs serial # is 53508. So from what I got out of Mr. Willer, this should be the correct engine. I also measured the pipe coming from the manifold and it was 1.25 inches in dia. and 17 inches long, to the top of the arrestor not including the piece that the weather cap is attached to. So could this be an original set up from IH? The previous owner said he bought it that way and he owned it for the last 35 years. I also noticed one shown in the manuals. I took some pics but am having a hard time getting them on here, I'll try a little harder if there is any interest... Dewight

[Bigdog]

Dewight - is that an I.D. diameter or O.D. diameter on the pipe? 17" would be correct for the length. But I believe a 48 cub would have had a 1" I.D. pipe.

[MelonKing]

Yeah, that was an O.D. measurement. One inch inside I'd say.

[George Willer]

Dewight,

We can agree that your engine seems to be numbered right for an original, so that shoots my theory. Here's another thought... The pipe sounds like the manifold is original too. (the original nominal 1" pipe was actually 1 5/16" O.D.). I think the smallest spark arrestor was made to fit nominal 1 1/4" I.D. pipe. Does yours have a reducing bushing in it?

[Jim Becker]

Repeating that I have never actually seen an original spark arrester on a Cub, so this is just educated guessing.

The parts book gives the appearance that the spark arrester screws right onto a 1" pipe, no bushing in the listing. The arrester was in the very early books, before the power unit came out. To change it for a different input size would only require changing the base, which is no more than a flange that bolts on the bottom. I don't have a parts book for a power unit, which would probably answer whether there was a difference.

[beaconlight]

I don't know if Rudi ever got around to putting the parts book for the harvester thressher combine I sent him but that is the source of my power unit. The poer unit does have a spark arrester and it is below the hood. It is 175 miles north at the moment so i will not be able to measure it. If rudi posted it is available there or if not perhaps he could look it up.

bill