beatsal

Thanks. Here are 2 pics.

1QwkSport2.5r

I would suggest not posting zip files. Zip files do not work well with mobile devices which many people use these days. Try posting .JPG or .PNG images instead.

Coxfledgling

Yep, refuses to open but thumbnail picture seen. That also refuses to open it be zoom inable.

You have access to a small lathe or are good at metal working at all ?

beatsal

Another pic

beatsal

Another pic!

beatsal

Not very good at metal work but think I can manage

Ployd

I would strongly recommend you remove the needle valve assembly and re-assemble with the fuel needle on the right hand side of the engine facing away from the prop (original factory installation). The way you have it installed is an accident waiting to happen.
Ployd in OZ

Coxfledgling

Absolutely as above...whilst it out, make a bracket to form a mounting point for a "slide flap" that will cover the Venturi hole to restrict the hole size via an RC servo which will allow "some" control of engine speed.

Alternatively make a Venturi extension that fits the Venturi tube outside with a similar ( cylindrical ) rotating means of controlling air intake diameter to control engine speed.

Also, a good fit tube with exhaust ports that fits over the engines exhaust ports and can rotate to control effective exhaust port size, thus giving some control of engine speed.

Note, the compression lever in your picture is set to full compression as it is right up against the stop pin.

How far have you stripped this engine down and does it run ?

What model where you thinking of putting this engine in ?

beatsal

I haven't stripped this engine. I had tried it 2 months ago and it fired but I did not run it - now having trouble starting it - maybe compression is too high? Thinking of trying it on the GWS Slowstick.

beatsal

Here is a pic of the fuel tank but not sure how it fits on the engine

DC Merlin fuel tank

Coxfledgling

Is there a central hole on the tank ?

Anything on the engine have a central threaded hole by chance ?

beatsal

Yes, there is a central 4 BA threaded hole in the tank, no central hole on the engine.

Ployd

It's not a Merlin tank as the original was a separate plastic unit that bolted to the backplate using the existing two screws.
Put that tank back in the "spares" box and learn how to make a small metal tank out of K&S tin plate. My friend, you have a lot to learn.

Ployd in OZ

beatsal

"However an RC fuel "kill" system could be made to stop engine when things go wrong."
Thanks. Looking for ideas how to implement this.

Coxfledgling

Hi beatsal,

I remember the clear plastic "squareish" fuel tanks well. I will try to postage a picture so you know what they look like.

Please post a picture of the end plate/rear c/case cover....

If I remember right the end plate has a central "spigot" that may be drilled and threaded to take a 4ba screw that you mention, to secure your tubular tank.

Does your tubular tank have a flat end plate, with the front end of the tank sitting in the recessed engine end plate ?

Soft fuel tolerant black rubber fuel hose can be "squashed" to cut fuel flow via a servo arm arrangement.

You could fabricate a servo controlled Venturi flap to control engine speed to some extent, and/or a servo controlled exhaust "ring" to restrict exhaust gas flow thus controlling engine speed somewhat.

In the past I have flown 2 channel RC planes with an uncontrolled engine, BUT, once you launch a plane of this type, you have NO ENGINE CONTROL whatsoever !!!!!!!!

These days I consider this to be very negligent !

You seem to be a tyro........

Powered free flight planes need a LOT OF SKILL to trim and fly and need LOTS OF SPACE to fly in !!!!!!!!!!!!!!?

Are you based in Canada ?

Go to a club and have a look-see.....slope soaring is wonderful, RC gliders are good.
Your Merlin would power a smallish glider, 2 channel with a smallish tank giving say a 2 minutes engine run to gain hieght, then hunt for a thermal or just glide around for a little while and land. You will need a suitable flying site, the skills to fly it, any legal requirements satisfied and INSURANCE !!!!!!!!!!!!!!!!!!!!!!!!!

beatsal

Here are 2 pics of Merlin, if not clear, let me know and I can take more pics

beatsal

Here are 2 pics of Merlin, if not clear, let me know and I can take more pics
I have changed the position of the needle valve to the other side as per comment rec'd

Ployd

This is a Merlin tank, 10cc capacity and bolts direct to the back plate via the 2 bolts. I believe the later ones were moulded from nylon and you may find on "evilbay"

This talk of fitting "flaps" to the venturi is a waste of effort and I would go far as saying that such a conversion would be beyong the abilities of Beatsal to execute and quite frankly unnessessary. If you wish to shut the engine down quickly then a servo activated cut-out that squeezes the fuel line would be a better way to go and simple to make.

Your choice of model Beatsal is not a Tomboy by a long shot (yes I have checked) and would have you crashing it faster than you can fly it. If a Tomboy style model is what you are after then go to Outerzone website and type in "Vic Smeed Tomboy" and you will see it is a simple model and practical for 3 channel radio. There are kits available from the UK and Australia.
If you go to Google type in " r/c Tomboy model" you will probably find videos and tutorials available. Leave the "GWS Slowstick" where it belongs....on the dealers shelf.

Ployd in OZ

beatsal

Still trying to start my DC merlin - very stubborn, shows sign of starting but sadly does not!
I have this glow plug - wonder if anyone would know or guess the make or model

glow-plug engine

Coxfledgling

Cox 049 baby bee...is there any gold anodising on the central Allo tank at all ?

Visit Cox model engine forum...does it turn over at all...?

Parts available from Cox international, exmodelengines, mecoa, and in the UK, Deb's model supplies...

Don't try and start it untill you have done your research, proper research.

Cox must have made millions and millions of these little gems, and others.

Did you get a plastic plane with it ?

They can be silenced and rc'd these days.

Your Merlin, are you using proper model diesel fuel like model Technics d1000 and have you backed off the compression lever ?

By the way it looks as if the prop is on backwards but that's the least of your worries.....

Coxfledgling

Could be a Cox peewee 020, measure piston diameter and visit cef, Cox engine forum.

Coxfledgling

Thimble drone...

Dens model supplies

beatsal

Yes, it turns. Here is a closeup of the tank, looks like anodised. Any suggestions for a prop to buy? No did not get plastic plane with it.

CLOSEUP OF TANK

Coxfledgling

Visit cef, Cox engine forum for encyclopedic knowledge data base...

Do your proper research...

The tank is between the engine and end plate with the mesh filter and needle valve...

Do your research

Coxfledgling

Did you visit the Cox engine forum yey by chance ?