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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Thu Sep 08, 2011 1:14 pm 
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I think there are a couple 4.5 X 3 props in my collection. I'll check. It sure takes a lot of activity to get one of these things going.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Thu Sep 08, 2011 4:45 pm 
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C-Lcarlisle wrote:
I think there are a couple 4.5 X 3 props in my collection. I'll check. It sure takes a lot of activity to get one of these things going.


Well, once you get it set up right, and run it frequently, it gets going pretty easily. It's the sitting around for months that makes it cranky, I guess gets gummed up everywhere, and takes some regular use to get it all cleared out.

the 4.5 x 3s might be just the ticket, give 'em a try. but keep a 4.25 x 4 in the back of your mind. And don't be afraid to throw the nitro at it. If it blows, well, it's had a good life.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Thu Sep 08, 2011 10:45 pm 
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I had told Frank that 10/20% nitro really didn't do much for a 1/2A engine. they run too cold and really only start getting serious at about 35%. Also get Cox high compression heads and 3 gaskets or if your really serious get a Nelson head and plug and get a further increase in rpm. When you get that sucker running at an rpm that makes your ears bleed then your just about right. Oh and swap out the single port cylinders and get a T.D one and use that. I already told him how to use a hot glove and a few other things but thats too much work for him so I guess he's going to run it like the old geezer that he is rapidly becoming.There are a thing or 2 that you can do around the reed valve and you can also make sure that the shaft is free in the case. If your gonna do it then you just gotta at least try and get serious. We want to hear that that model was faster then a goosed rabbit.
Dennis


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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Fri Sep 09, 2011 6:29 pm 
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Frank, Ray
There is a mod I do to all of the Cox 049's I have.

If it has a metal Backplate I pull out the wire mesh screen from the intake.
If it has a plastic backplate (separate fuel tank, MY Favorites) I remove the wire mesh screen and trim the plastic, that held the screen, down till it is flush with the shoulder the screen set against. This increases the space between the firewall and the intake allowing the engine to breath easer.
Clancy

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Fri Sep 09, 2011 10:40 pm 
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Clancyarnold wrote:
Frank, Ray
There is a mod I do to all of the Cox 049's I have.

If it has a metal Backplate I pull out the wire mesh screen from the intake.
If it has a plastic backplate (separate fuel tank, MY Favorites) I remove the wire mesh screen and trim the plastic, that held the screen, down till it is flush with the shoulder the screen set against. This increases the space between the firewall and the intake allowing the engine to breath easer.
Clancy


Both good ideas. You can also drill out the venturi a little, to .078 (5/64") or so. I read you can go to .093 (3/32") but I haven't tried that large, doesn't seem like the fuel draw would be there.

Now I'm not sure about those numbers, need to go measure one but I'm too lazy at the moment. Perhaps someone out there can confirm or deny these.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Sat Sep 10, 2011 12:09 am 
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Ray,
The main thing to remember is that as you increase the size of the venturi you also increase the fuel consumption. The trick with 1/2A and every racing event is go fast and do it on less fuel then the others guy and finish first.
I guess what really needs to be kept in mind is that it is supposed to be a fun event. Better not get too wrapped up in being the fastest and lose sight of that fact. Not that i think that Frank is really interested in total annihilation of the other flyers.
Dennis


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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 7:41 am 
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I got about a lap and a half on one flight with the engine in Dil-Bod. Scuffed up the rudder on the landing.
Dave Keats fiddled with props and fuel and glow heads. The final diagnosis was that it had low compression and a new cylinder and sleeve were needed.
What to do?

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 7:06 pm 
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Hey Frank, sorry I just now noticed this post...I'll get you a new cylinder/piston assy. in the mail ASAP. I'll try to pick out a good one, make sure the rod is set, etc. Sorry it's giving you so much frustration.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 7:13 pm 
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Hold on Ray.............I have a bunch of production engines and spare parts.....certainly enough to get Dil-Bod a qualifying flight.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 9:32 pm 
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Frank, Ray
If you have a loose rod to piston fit I have the Punch and Anvil sets for Cox .049/051, .020 and .010 engines if you need them reset.

In my last post I mentioned some mods I do on my Cox engines. I forgot to add one, To allow the use of an electric starter you need to add a steel shim washer between the crankcase and the back of the prop drive washer. Otherwise you are rubbing Aluminum on Aluminum which wears very fast. I use some .004 Stainless Steel shim washers that just clear the crank shaft. No noticable wear after mod.
Clancy

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 10:01 pm 
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C-Lcarlisle wrote:
Hold on Ray.............I have a bunch of production engines and spare parts.....certainly enough to get Dil-Bod a qualifying flight.


Well OK, but I've just set the rod in one and it's all packaged up, holler if you need it.

Clancy, I have a setting tool for .049, and use it often, thanks. If my .010 ever loosens up I'll keep you in mind! But I don't really run it enough to worry about it.

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Mon Sep 12, 2011 11:06 pm 
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Ray I have 5 Cox .020 PeeWee engines installed or committed. They were all obtained used and were all loose. One of my two Cox .010 TD's NIB had a loose rod!
Clancy

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Tue Sep 13, 2011 3:58 pm 
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Clancy, do you have in mind mailing the reset tools out on loan, or having us mail the piston/rod assys. to you for you to reset? And what would be the cost of whichever option you like?

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Wed Sep 14, 2011 11:39 am 
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Will someone please explain this punch in detail/with photoes?

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 Post subject: Re: An engine for Dil-Bod?
PostPosted: Wed Sep 14, 2011 12:10 pm 
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Oops, Frank's feeling left out in the dark.

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