magneeto

[el60]

I have a Fairbanks and morris mag from a 1940 B. It is a rv mag What would it be worth. It is a hot mag I actually got the B running with this mag.

 

[Anonymous-0]

Worth enough to be known to come up missing at shows!

 

[el60]

This mag has RV 2b on it. Also has what I would guess to be a parts numer on it it is 170867. Can anyone tell me any infor what year or anything about it?

 

[teddy52food]

I have a couple of those if someone needs one. I know one has spark & I think the other one does too.

 

[Harvey Brinker]

There were several for sale at Portland, IN this fall in decent condition,,one I recall was priced at $350.

Considering their unusual shape, large size, and the fact that they can be buffed up to a high luster helps them to really set off the looks of a tractor.

I think they were only issued with the tractors in the mid-1930's. I was told by a magneto repairman that the reason they are not all that common today is because when the Wico came out it had a bit hotter spark and was better protected from the weather when the tractor sat outside. Consequently the F-M's were taken off, laid aside, and scrapped out for the metal during the drives of WWII.

All in all, a quality detail that helps denote a tractor as being a bit unusual..an item worth having.

 

[appraiser]

This may be a strange question but is an RV2B for an early B and an RV2A for an early A tractor? Are they similar in rarity?

 

[Kendog]

I am interested, and can be reached at [email protected]. Thank you.

 

[Harvey Brinker]

There is a superb article on these mags in the September 1996 issue of GREEN MAGAZINE written by Greg Stephen.

There is a very complete table showing the serial numbers of the various tractors that came from the factory with these mags. To generalize they were put on during the first years of production of the A, AR/AO, AOS, B BR/BO starting in 1934 and ending up in mid 1938. (There was also one for the GP, but it was base mounted, as opposed to the others which had the typical flange mount.)

Greg states, "Now comes the bad news. The Fairbanks RV magneto is very difficult to find. Once found, it is even more difficult to repair. Parts are almost nonexistent and the biggest problem is the condenser." "As can be seen it is a "flat" condenser as opposed to the tratidional round."

If Greg were writing the article again today I think he would modify that statement. During the past 14 years our hobby has advanced tremendously in the after market items available and the specalized services available. This fall when at Portland, IN for the Tri-State Engine Show I specifically talked to several magneto repair services about the F-M mags. They stated that they had no difficulty making repairs, and could get them to spark just as hot as the other brands. Ten years ago I could find no one to repair my old Splitdorf mag for my 1929 D. A year ago,,thanks to the internet, I made contact, mailed it to Maine and had it repaired to like new condition.

I fully agree with Greg when he concludes the article with, " I think this magneto has been seriously over-looked by all but the most advanced collectors and deserves more attention as the sophistican of today's restorations increases."
Harvey

 

[PopinJohn]

The RV2A (upright mounting) was used on open fanshaft JD A's 1934-35. The DRV2B (lays to the right) was used on closed fanshaft tractors. The A and B were same, except some A's say 35-D on the flange.

 

[Harvey Brinker]

Appraiser ask several good questions which I will attempt to answer, again from the Greg Stephen's article in the September 1996 issue of GREEN MAGAZINE.

The first F-M mag used with JD was the RV2A which was used on the A tractors starting SN 41000-424024 and the JD AR/AO SN 25000-251485. These mags had a vertical flange mount..so that the spark plug wires came out of the top of the mag just under the gas tank.

However when the JD B was introduced there was not enough room to position the vertical mounted mag as the gas tank was too close to the governor assembly. To correct the situation they came up with a horizontally mounted magneto with the spark plug wires coming out toward the front of the tractor,, this was the DRV2B. On the ones I have examined the "D" is always hand stamped into the metal and the RV2B is cast in raised letters.

If I understand, JD wanted an interchangeable mag they could use on both the A and the B. Then Greg states,"To accomplish this, JD had to change the flywheel on the B and BR/BO. The new flywheel carried the part number AB705R and had the flywheel markings indexed differently than the earlier AB253R flywheel." For the B this happened at SN14038 and for the BR/BO at SN325601 at which time the part number changed and the mag carried only the RV2B,,,and no longer the hand stamped "D".

In response to your question about which is the most rare,,,based on the chart Greg provided my guess would be that the Vertical mounted RV2A would be most rare as it was only used on the first of the A, AR/AO tractors.

Unlike the other mags these do not fire both at the top and bottom of the stroke,,,and are a bit more tricky to time properly. Others have written concerning this topic in the past.

I really do not have a clue as to what extent the "flywheel markings indexed differently". So if anybody knows about that aspect of this topic I for one would be interested in the information.

Anyway, if you are really into this topic you should read Greg's article and work through the facts with your specific mag, and tractor.
I hope this has been helpful, Sincerely, Harvey

 

[Fixalinc]

Depends on condition. There is and has been way too much over priced JUNK for RV2 mags on ebay and other auctions. One in excellent condition restored right is hard to find. Condenser not a problem use a film capacitor all the mag repair shops have replacements. Coils there are rewinds available will make it much hotter. If shoddy wanna be coil in it = poor fire, junk mag. Most of them have sweated so bad and all corroded inside the all aluminum housing the bearings need to be replaced and aren"t. Bearings readily available just a standard E15 mag bearing. Worth today half what they were 1 to 3 years ago. Check out the great mag info Duane left us.
2 cylinder mags

 

[el60]

the mag I have came off running tractor.