COX RR-1 retrofit from ebay

If so then it is a real hybrid. ..thanks to the interchangeable parts still in very good fit...was it really so that the older COX ARF models had their names marked on the cylinder ?

balogh wrote:If so then it is a real hybrid. ..thanks to the interchangeable parts still in very good fit...was it really so that the older COX ARF models had their names marked on the cylinder ?

I'm not an expert by any means but I believe the p-40 is the only one that was done with.

Jim

I think P-40 model required a bit more power, and this type of cylinder was modified accordingly. I agree with Jim, that is the only cylinder market according to the model it was built for.

Lot of later product engines had the #1 (Black Widow) cylinder, which I *think* is similar to the P-40.

Too bad the RR-1 was not exactly original, but both the backplate and the cylinder are easy to replace.

Some RR1s came with vented backplate, photos from Marks .049 Collectors Group

Thanks it means the only transplanted item is the cylinder. But the compression is excellent so I will not swap it...url=https://servimg.com/view/17754239/151][/url]

I believe the backplate fill tubes on the RR-1 mentioned did not have the tubes drilled through. I may pay to check.
Indeed, the P-40 cylinder was specifically fitted to the P-40 aircraft. It used a Babe Bee engine with a twin bypass cylinder with SPI, rather than a #2 single bypass cylinder. The heavy P-40 model required extra power to perform adequately.

balogh wrote:Thanks it means the only transplanted item is the cylinder. But the compression is excellent so I will not swap it...url=https://servimg.com/view/17754239/151][/url]

Put one of Bernie's TD cylinders on it. That's what I did with my space hopper that came with the incorrect cylinder

Good idea but it would still not make it a genuine RR-1...and I like the thin wall antique cylinders.

I will tach it and check if compression remains strong when hot..an indication of low previous runtime. Just got a white horseshoe backplated product 049 with stepped cylinder wall at a low price...it looked overly misused when I bought it...I bought it for my spare parts stock....surprise surprise....it arrived as a practically unused engine that must have sat in a drawer after a failed maiden flight of a COX Super Sport Trainer since the mid70's...my guess is that in the heyday of COX it was not customary to use engines for hours after hours they were so cheap and widely available...they were swapped with new ones after a few hours if the plastic ARF plane survived that runtime at all. My best pre-owned engines all come from the 1970's and before.

According to the Cylinder Identification file, the RR-1 had a thin wall duel bypass cylinder with open exhaust and SPI. Well that's exactly what you have with the P-40 cylinder so I'd leave it because it's probably as close as you'll get to original apart from the "P-40" stamping.
I have an original P-40 Babe Bee and it's a very strong engine.

The P40 cylinder was the first cylinder Cox ever stamped. The RR-1 should have a thin walled, 2 bypass port, unstamped cylinder for it to be original. Some early postage stamp engines have this cylinder and this is where I harvested some of these cylinders to bring my RR-1's to original condition. The backplate needs to have the bright zinc chromate finish for it to be correct. Vent tubes are OK if they are un-drilled. On one of my RR-1s it had an unstamped Tee Dee cylinder on it with 2 bypass ports and 4 boost ports. I left this one the way it is.

Everything is as you described except the cylinder which is stamped and the vent holes which are drilled. There is no text stamped on the backplate .

Thanks for the information.

That is good info I haven't heard they made the RR-1 with that back plate non-drilled filler holes , Thanks getback

KariFS wrote:I think P-40 model required a bit more power, and this  type of cylinder was modified accordingly. ....

Kari thanks for this info...looking into the cylinder it shows the standard 2-port 2 bypass design that leaves me puzzled on why this cylinder of the P40 was supposed to deliver more power...the glow head is the high compression design with 3 shims, but any cylinder would prvide more power with a high comp head..any info on what made the P40 cylinder (maybe the height of porting/ ignition timing?) more powerful than the normal No1 design, will be appreciated.

[quote="Oldenginerod"].........Indeed, the P-40 cylinder was specifically fitted to the P-40 aircraft.  It used a Babe Bee engine with a twin bypass cylinder with SPI, rather than a #2 single bypass cylinder.  The heavy P-40 model required extra power to perform adequately.[/quote)

Thanks oldenginerod, so I understand the P40 cylinder is nothing special, it has 2 bypass ports like most of the COX cylinders (except No2 and No8) and as such will deliver more power than a probably cheaper (due to only 1 bypass port machined in the cylinder) No2 design, commonly used on lighter COX planes...

I'm not sure what you paid for it, but if the seller was stating it as original you might contact him and discus a refund or compensation. The small needle valve head (c. '68 and later) is always a giveaway.

The P-40 cylinder was also stamped with a 1 and did appear on Space Hoppers and later RR-1's.

Mark Boesen wrote:I'm not sure what you paid for it, but if the seller was stating it as original you might contact him and discus a refund or compensation. The small needle valve head (c. '68 and later) is always a giveaway.

The P-40 cylinder was also stamped with a 1 and did appear on Space Hoppers and later RR-1's.

Thanks,

I understand the P40 cylinder is then authentical on a RR1, so the only thing that is a transplant is the needle valve?

No, the original cylinder was a twin exhaust port type, but it didn't have any stamping until later when it had a #1 stamp...and not 100% sure on the #1 stamp, as i've heard different opinions and don't remember what Mud says...who is the ultimate expert on the older Cox stuff.

It looks like the backplate with vents drilled out, needle, glowhead (hicomp) and cylinder are not original type, didn't see spinner.

The good news is the tank and case look good, you could get on ebay and pick up a basket case Space Bug, the later version for a cylinder, glowhead and needle.

http://www.ebay.com/itm/L-M-COX-SPACE-BUG-049-MODEL-AIRPLANE-VINTAGE-ENGINE-049-/272027212647?hash=item3f5615db67%3Ag%3AhyMAAOSwwbdWLWi3&nma=true&si=owX4t1DhgxBgu9vvvsyr28MDCv4%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

Yes I agree the backplate and the cylinder both smell on the RR-1..the needle valve resembles the one on the old photo of crankbandr shown a few postings up..


All in all I am not particularly a RR-1 collector but a user of the engines, and as such I did not expect a brand new, genuine RR-1...what I got seems to be in a good order.

I am more particular about the top-notch COX gems of the TD family or even the old reedies. The RR1 is built of a bit too many moving components for my taste, all prone to fail and cutting performance...not that I do not like it. It is a nice evolution milestone of the rotary valve intake concept that peaked clearly in the TD design.