Differences between Sure Start And Product Engine With Horseshoe Backplate

Ercoupe is a beautiful airplane, once in a while I've managed to see one at an airport, a rare sight to behold. I pulled off the jug from my son's Babe Bee field find that I cleaned up, to further remove rust from it. Lo and behold, it has only one bypass flute on one side of the cylinder, about the same size as one on the 290. It has SPI. From that with the Thimble Drome text stamped on the aluminum tank and tapered narrowing crankcase portion supporting the crankshaft, I don't know if someone could put a date it.

GallopingGhostler wrote:Ercoupe is a beautiful airplane, once in a while I've managed to see one at an airport, a rare sight to behold. I pulled off the jug from my son's Babe Bee field find that I cleaned up, to further remove rust from it. Lo and behold, it has only one bypass flute on one side of the cylinder, about the same size as one on the 290. It has SPI. From that with the Thimble Drome text stamped on the aluminum tank and tapered narrowing crankcase portion supporting the crankshaft, I don't know if someone could put a date it.

According to Martin Hepperle, they only used the Thimble Drome text & stars on the tank up until 1969, so it would be pre-1970.

Rod.

dckrsn wrote:Bandit, I for one would really enjoy some Ercoupe pics.
When I lived in L.A. there was one based at Santa Monica.
Facinating plane. Here's a little piece of Ercoupe history.
Bob

http://airpigz.com/blog/2011/2/25/1941-air-race-porterfield-gets-whipped-by-jato-ercoupe.html

Alrighty As soon as the weather improves enough I'll go down to the air park and take some pics it's freshly restored. (Bandit)

Oldenginerod wrote:

GallopingGhostler wrote:Ercoupe is a beautiful airplane, once in a while I've managed to see one at an airport, a rare sight to behold. I pulled off the jug from my son's Babe Bee field find that I cleaned up, to further remove rust from it. Lo and behold, it has only one bypass flute on one side of the cylinder, about the same size as one on the 290. It has SPI. From that with the Thimble Drome text stamped on the aluminum tank and tapered narrowing crankcase portion supporting the crankshaft, I don't know if someone could put a date it.

According to Martin Hepperle, they only used the Thimble Drome text & stars on the tank up until 1969, so it would be pre-1970.

Rod.

You're correct I'm sure its older then '69-'70, but remember even though the "Thimble-Drome" was dropped off the tank in '69, but there were a lot of 'em made and they continued to show up for a year or two after. Notice the NIB Bee below with small head needle and stepped cylinder.


I'd look on backplate and see if it says "Made in USA" if so it's c.'64-'69
If theres a slight groove on case below cylinder, if so its c. '62-'64, no groove, '59-'61

well I Just keep learning things about these engines , Mark is that info from the book or somewhere else ? Eric

It's info I've learned over the years, thanks to fourms and collector friends. Remember years are almost always approximates, if Cox ended production or changed something, it might be months before they ran out.

I think i'll put together a basic "Bee ID" chart, it would come in handy.

Mark Boesen wrote:I think i'll put together a basic "Bee ID" chart, it would come in handy.

Mark, that would be beneficial, help to identify an engine's age. Regarding gray areas, these older Coxes are far back enough that IMO plus or minus months don't hold that much significance.

Thanks to your observations, I gather that my son's Babe Bee is in the 1964 to 1969 category, as the back plate does say Made in USA. I've got another that is in a little better condition that is identical. Both have the groove in the crankcase for the snap spring no-drag starter and crankcase tapered crankshaft bearing with bump at the prop thrust plate, as in the early 1960's crankcases. Both have SPI, but only one bypass port. They are sweet running little engines.

Mark, do you know if the "bee-style" engines originally fitted to RTF planes had the text on the tank or not?

Yes, the ID chart would be very useful

Mark Boesen wrote:I think i'll put together a basic "Bee ID" chart, it would come in handy.

I'd really like to see that Mark. I have saved NUMEROUS charts on specs, formulas, etc. in my CEF folder. I need to back-up it's contents to an external drive (again) actually. It's currently over 2Gb full of fellow modelers build-photos and other useful misc. hobby info.

A chart would be awesome, and would definitely help one with identifying engines.

Here's one i cooked up, it needs work...

All this info and much more is on Marks site.



Very early Bee, with 3 piece piston. It has the fillister head screws so not the first Bee






One of the first Golden Bees, also has 3 piece piston (sent it to Kim for the race)

i wanna do one on the glowheads...but thats gonna take some time. I also think it would be neat to have a full page "flow chart" of photos of all Babe Bee changes from '56 to say early/mid 70's.

Well then, allow me to say that you are wasting precious time. Get to it. Thanks so far, it has been good.

Two of my Babe Bee's have the large knob on the needles, but they are real short. The spring bears right against the knurled knob. When were they used? Also another Bee has the same type of tapered case with the little bulge at the prop hub, but its  thicker, the whole front is a little bigger. When was that in use?
I have four Babe Bee's from when I was a kid, probably had them for 45 years. Over time some of the parts may have been mixed up. I would like to straighten them out the way they belong and freshen them up. They do all run, but some dont look to pretty.
Phil

chevyiron420 wrote:Two of my Babe Bee's have the large knob on the needles, but they are real short. The spring bears right against the knurled knob. When were they used? Also another Bee has the same type of tapered case with the little bulge at the prop hub, but its  thicker, the whole front is a little bigger. When was that in use?
I have four Babe Bee's from when I was a kid, probably had them for 45 years. Over time some of the parts may have been mixed up. I would like to straighten them out the way they belong and freshen them up. They do all run, but some dont look to pretty.
Phil

I'm not sure about the shorter needle, i've got a couple, but don't really know...guess and say Prop Rod or Mercedes Racer, I'll need to study that? The fatter case came out about '70, story goes the cutting tool used was worn, but also story that it redesigned to be more indestructible.

Yes, the short needle was used in the 1/20 scale tether cars Corvette, Buick, Chaparral to fit under the body.

Thanks For the reply Mark you do know a lot about these small engines and all references wee can pull together is very helpful. That lot I got of a bunch of difft. parts are really being a pain to fit pieces together and try and make them some what correct . ( this I will never do again ) I hope I did just get this with others that has a nice little steel plate mount that looks like what roddie had made . Eric     Well now I see the back plate is trash, bent/cracked O well I have more .

getback wrote:Thanks For the reply Mark you do know a lot about these small engines and all references wee can pull together is very helpful. That lot I got of a bunch of difft. parts are really being a pain to fit pieces together and try and make them some what correct . ( this I will never do again ) I hope I did just get this with others that has a nice little steel plate mount that looks like what roddie had made . Eric      Well now I see the back plate is trash, bent/cracked O well I have more .

I don't remember seeing this Eric.. Maybe a tougher "steel" mount-system is too rigid during a ground-strike? Hope you saved the NVA/spray-bar.

I searched this thread today in hopes of finding info on the Sure-Start "backplate". In particular; any tips on the assembly of the reed-holder. They're the cap-style without the gasket-shaped flange.. and are new to me.



I checked the fit and it's snug. I didn't "fully" seat it. I would imagine the assembling to the crankcase would fully seat the part.. but I don't want to stress or break anything..

Any tips?

TIA  

No the crank is not going to seat those. Instead the crank will chew it up and destroy the reed too. Make double sure it is properly seated before final assembly.

Phil

pkrankow wrote:No the crank is not going to seat those.  Instead the crank will chew it up and destroy the reed too.  Make double sure it is properly seated before final assembly.

Phil

Thanks Phil. I see now that the cap itself will slide through the back of the case. It looks like the cap snaps-on.. and I'm glad I didn't do that without a reed installed. Reed-changes or cleaning must be a PIA.. Have you ever had to remove a cap?

I only have one engine set up with this type of retainer. It came apart with moderate effort by wedging a thumbnail in. I only took it apart once. I would have hooked it with a wide flat screwdriver from the inside if this didn't work.

Phil

pkrankow wrote:I only have one engine set up with this type of retainer.  It came apart with moderate effort by wedging a thumbnail in.  I only took it apart once.  I would have hooked it with a wide flat screwdriver from the inside if this didn't work.

Phil

Thanks "again" Phil. They do seem fragile almost to the point of being sacrificial.. like a case-gasket. That's ok.. I have a few spares in the 10-piece "bulk-discount" pkg. I got from Bernie. The backplate/snorkel assemblies came that way too.. in 3-packs.. of which I bought two.. along with two 12-pack backplate screws. Enough for 6 engines. Wanting to give Matt some business too; I bought 6 needles, some Mylar reeds and a Tee Dee radial mount from him. Dan McEntee also sold me a bunch of NOS Perfect wedge-tanks in the small sizes I used to run.

I've had some engine parts broken-down separately in parts-organizers for the longest time. Crankcase assemblies, cylinders (ID'd) and pistons reset. Maybe 8 engines-worth, from various Bee's and product-engines sourced over the years. Tank-bowls (5cc and 8cc) and their associated backplates/needles/screws are in another organizer. No traceability to the original assemblies whatsoever.. but that doesn't really bother me.  I'd gotten away from running tanked-Bee's on my model airplanes. Instead of acquiring additional complete engines.. I reconfigured the ones I had to suit my needs. I'm sure that these new backplates will work as well as the old ones did for me. I'm eager to test balloon-tanks too.

Eventually I'll design a modular firewall that will utilize the snorkel/choke-tube. I actually like the design/function even though it's obtrusive when compared to a conventional flat/radial mount. It's really the first effective application of a choke for the Bee engine.