Difference between McCoy Lightening Bolt and plain RH engines?

What is the difference between the two engine lines?

Tight Lines,
Tim

Well, I can say this much:

I have two plain McCoy RedHead 35's, and one with the lightning bolt. The one with the lightning bolt is my all-time favorite - it's been rock-solid dependable, starts great, runs with a nice 4-2-4, it's a great engine. The other two, I haven't had as much luck with. Not sure why...

The way I recall it, the original engine used an unbushed case, with the crank just running in the self-metal of the case. This became a rapid-wearout area. The Lightning Bolt models were very much the same engines with the refinement of a proper shaft bushing, PLUS there was a certain amount of quality control performed, which greatly enhanced the overall quality.

The usual procedure had been merely to assemble and package the Red Heads, with no check for decent compression, too loose, too tight, nothing of that nature. It was said that one out of three of the original ones was so badly mismatched on parts that it was not going to run no matter what, and then out of the remaining 66% of production, a quarter part were still junk, even if they might run, and a quarter were pretty good (let's see - that's 16.5 %), leaving a full one third of production that was at best only "average" for a Red Head, which in my book wasn't saying much.

(I could have the numbers scrambled some, the basic idea of how many were worth taking the inordinate breakin time needed is from George A., who liked McCoy 40's pretty well.)

K.

From what little I know of these engines, the plain redheads did have a bushing...steel, or something like that. The lightning bolt models had a bronze bushing and it seemed like the quality control was upped a notch or so over the non-lightning bolt models.

Happy flying!

>From what little I know of
>these engines, the plain redheads
>did have a bushing...steel, or
>something like that. The

Gene;

The earlier ones that I had (and still have a couple of carcass engines) had what appeared to be a sintered steel bushing.

When I was young and broke (as opposed to now being older, married and broke) I was given a number of older Testors/McCoy Redheads that the owners claimed would not run, so were in new condition. All of them did, in fact, eventually run without part swapping. I did find that these engines were unforgiving if overheated or run over lean. Because they flew on profiles, I didn't have much of a problem with overheating due to insufficient air flow. And, I ran them on all castor fuel, so I got a lot of hours out of them. Two are still serviceable. Also, once you got one to run, never take it apart save for the backplate. Once disassembled and reassembled, it was hard to regain compression.

What DID ruin them, though, was a batch of K&B 100 fuel that must have been low on castor or had synthetic lube. I wrecked two in one afternoon before I figured out what was going wrong...

I think GMA's estimate that 1/3 of the old RHs (pre lightning bolt) would not run out of the box is probably a little high. I am sure that some didn't run, and some that did only barely run, but I think that it was more a factor that many folks didn't know what to check for or how to start an engine. Of the ten or so that I have owned, if it had compression and a good plug, then it would pop and eventually start.

I'm looking at a photocopy of a Peter G. F. Chinn engine review from an August, 1967 Model Airplane News magazine. He mentions these improvements:

1. Main casting strenghtened with additional webs
2. Mounting lugs lengthened and with elongated slots
3. Sintered iron main bearing replaced with oil retaining Bunting bronze
4. Crankweb flanks cut away to provide better counterbalancing
5. Various changes made in porting
6. A "blowproof" .015 in. soft aluminum head gasket replaces former composition type
7. Pistons made from forgings resulting in improved life and reduced wrist-pin wear

Maybe all of you engine gurus will understand all of this.

Mel: Very good summary. I have every one of Chinn's various Redhead reviews, by the way.

As constant readers of this Forum are tired of hearing, I have some experience with the Redhead, and like them. The metallurgy part has been amply covered, so here are a few more opinions and observations of mine in no particular order:

1. The Bolt models, although timed a bit differently, really are no more powerful than the earlier models.

2. .40 Pre-Bolt and Bolt models are quite collectible, and make a fine stunt baffle engine. Yes, there are nowhere near the power of a OS FP .40. The Bolt .40s have an enlongated slot for the front lugs, which is preferable to the open, "U" shaped slot on the pre-Bolt .40 models. They break easily.

3. The first McCoy Redhead .35s (circa 1956) have no flats on the side of the venturi. They are somewhat rare and collectible. Most sellers don't know this, so scarf them up. Parts interchange up an down.

4. The later pre-bolt .35s have the plug offset. I see no difference or advantage in this. You also can find "mistake" heads with the plug hole essentially drilled in a random position.

5. The sleeve can only fit into the case one way: the right way. This is an advantage over Fox when you're cleaning the dirt out of them after you wreck.

6. Another advantage over Fox: the needle. No brainer.

7. Blue Head RC Bolt models convert just fine to CL. It is the same engine as the Redhead.

8. Every now and then, you can score one that really 4-2-4s well, and has a tad more power vs. a Fox to boot.

9. Beautiful engines out the box (red on black on chrome on gold ), they look a little tatty with use. Advantage Fox here, with its rugged good looks.

10. Was there a better buy in modeldom than the McCoy .35 at $5.95 in the late '50s?

11. You can find them all day at swaps for around $20 in excellent shape. Old time RCers who started on CL will give them away. Accept.

12. They do like castor, but a castor/syn mix works fine.

Currell

When we were young and broke we used to be given old Mccoy R/h and Sportmen series. The drill was to squirt a little 30 wt oil in then prime and then flip hard. Some of those engines when they landed had NO compression but really did soldier out the summer wheather it wanted to die or not, you know kids at that time squeezed everything that they could out of the stuff that they got. I used to fly a ring jr with a sportman 098 that had really seen better days, come to think of it the plane had too.
One of these days I'm going to find a really new 098 and see how they really ran with a good fit

I've heard that the Redhead 35 will grenade if you try to run a muffler on it. Are they touchy about having a muffler on them?

Currell’s points are well stated - #9 really hits the mark. I truly believe that people were seduced by the looks. I can still remember when they came out in the local hobby shop (Luther's, in Tonawanda, NY). A bright shiny red head engine, packaged in a clamshell plastic box with a transparent lid – it presented like a watch! Next to it, I remember seeing a Fox .35, dull case, in a cardboard box, costing 4 or five dollars more! Guess which one had the sales appeal.
Regarding quality control – I do not believe the phrase existed at McCoy – read on. I was given a new .35 a few years back. Trying to run it on the bench, it would only run on an exhaust prime. No matter what I did, it would not draw fuel. The usual steps were taken – check the needle valve, blow fuel through the spray bar, everything was clear. Then, I tried an intake prime – squirt fuel in the venturi, flip the prop and ---- the fuel just sat there. I removed the spray bar and could not see the crank – they had forgotten to drill thorough the crankshaft bushing. The hole was blind! A quick job with a ¼” bit, deburr and it ran perfectly. Some quality control!!
Bob

Steve. I've never stuck a muffler on one.

However, if the back pressure isn't too high, I would guess that a McCoy would survive.

Of course, some of the wags out there (and you know who you are) will say that Redheads grenaded themselves pretty well without the benefit of mufflers, thank you very much!

>Of course, some of the wags out there (and you know
>who you are) will say that Redheads grenaded themselves
>pretty well without the benefit of mufflers, thank you
>very much!
>
Mufflers on all of the older engines do one thing in particular; they promote additional engine heating without adding enough new heat dissipation capability to match. McCoys are less able to handle overheating than Foxes, so special care is probably in order. I found that using 15% Nitro in a fuel mix with 25% oil increased the fuel consumption enough to help keep a muffled Fox running in roughly the same heat range and also recaptured most of the lost power.

That was with the earliest of mufflers for that engine, all as strap-ons, in the late 1970's.

I'm among those who think there are enough Foxes around to satisfy requirements for 35-size 4-2-4 engines, not to require me to change my predjudices against the Macs.

Kiwi

I've run mufflers on them with no apparrent adverse effects. First ones were Tatone Peace Pipes. I still run mufflers on mine and use the peace pipes and a couple of tongue types I've built. I did ruin a redhead .35 while using a muffler, but it was from homebrew no-castor, 20% Klotz fuel. I've lot's of hours on the Series 21's with mufflers also (never ran one of those on a model without a muffler).

Herman

Guys, a Testors McCoy Red Head with lightning bolts on the case just went on auction on e-bay. Item # 1761184595. It looks good, but you know how that goes. I have no idea who the seller is. This is just for info. I am not advocating anyone bid on it. But the subject came up and here is one. You can see the elongated front mount holes.

...What DID ruin them, though, was a batch of K&B 100 fuel that must have been low on castor or had synthetic lube. I wrecked two in one afternoon before I figured out what was going wrong... Regards - Bob Kruger

I think K&B 100+ was all synthetic lube. True?

I remember reading somewhere that sometime after the initial release of the Red Heads, all remaining engines were assembled in a warehouse by people who did not know engines. If true, these are probably the ones that were hit and miss. I think the time frame was about the time the price was dropped.
I have two that have excellent fits ...they will eventually get their turn.
George

Last year I dug out an old bolt motor that I was given.
Was going to use it on an old F.S. I had.Tried to run on
the bench first and guess what, on comp.Had to prime with
motor oil to start it. Later I remembered someone had used
a punch on the piston dome to make a better fit. Anyway
I tried it.It was that or the trash can,so I didn't care
if it worked or not. Put the piston on something flat and
punch the top of the dome with a round punch.I went a little
much and to lap it some.Boy! what a defference it made,lots
of comp.Had to brake it in all over again.Runs great!!
This worked only for me,don't know if it will for you,don't
do it unless your welling to throw the the thing in the trash.
Evan

Long,long ago and far,far away, we used to knurl pistons so they would fit into the bored cylinders. This was on old Chevy blue Flame sixes. What ever works. I tried to fire up an old Red Head this afternoon. Slobber and pop and back fire. Every time it back fired the prop nut came loose, and I had it on TIGHT.!! I was hoping to put it on an OTS or a trainer. No loss.

I've had engines that would do that trick, but not a Mac.

My problem was the puny dimples on the thrust washer wouldn't get a bite on a hard prop. GMA told me to use a GH Torp's thrust washer, but neither he nor I had a spare when the subject came up!

I'm at this eMail address - [email protected] - not at al sure if I have your eMail (re: my plans collection vs. plans I want to add to it).

Kiwi

> ...What DID ruin them, though,
>was a batch of K&B
>100 fuel that must have
>been low on castor or
>had synthetic lube. I
>wrecked two in one afternoon
>before I figured out what
>was going wrong... Regards
>- Bob Kruger
>
>
> I think K&B 100+ was
>all synthetic lube. True?
>

If I remember, it was originally castor. At some time, they slipped in some synthetic and either kept it as a synthetic blend or went all synthetic.

My suspicion was that the batch I had that tanked my engines was either synthetic or synthetic blend, and possible light on lube. I never bought another gallon. Went back to running Fox fuel, which really hurt the budget. Then, Doug Taffinder started selling good fuel properly blended at a reasonable price. All was well again, albeit my engine inventory was somewhat depleted.

to ejones

What type and size of punch? i have two mccoys and a k&b that need this. I was thinking of just chroming the pistons a little to fix it. Dana Email [email protected]

Bob,
I think that when K&B started using synthetics, their K&B 100 was all castor and their K&B 100+ was synthetic. They offered both versions. That may have changed later.
I can't remember if their 100+ was all synthetic or a blend.
George

About 35 years ago I had a K&B .15 which I nearly wore out - probably with the needle set too lean. It got to the point that I had to prime the exhaust with pure castor oil to get enough compression seal for it to start. Once it started it seemed to fun fairly well but with some lost power.

About 35 years ago I had a K&B .15 which I nearly wore out - probably with the needle set too lean. It got to the point that I had to prime the exhaust with pure castor oil to get enough compression seal for it to start. Once it started it seemed to fun fairly well but with some lost power.

>Bob,

> I can't remember if their
>100+ was all synthetic or
>a blend.
>George
>

Perhaps they should have called it K&B 100 Minus....