By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by CML

Engine projects

or I THINK it's all there ?

All Topics | Latest Posts

Search for:  in Thread Title in  
ASH.12/10/2019 22:32:08
avatar
334 forum posts

Nice work Jeff.

BTW nothing wrong with MDS. My 48 served me well and got me through my A test to everyone's amazement.

Robin Colbourne13/10/2019 01:26:29
avatar
582 forum posts
17 photos

Hi Jeff, Is your latest project based upon a Super Tigre 71?

A rare beast if it is!

Robin Colbourne13/10/2019 13:09:39
avatar
582 forum posts
17 photos
Posted by Robin Colbourne on 13/10/2019 01:26:29:

Hi Jeff, Is your latest project based upon a Super Tigre 71?

A rare beast if it is!

For some reason I couldn't edit, this, so to be specific, I meant the Super Tigre G71 RV, although it could equally well be the G60 RV.

jeff2wings13/10/2019 13:22:47
avatar
807 forum posts
1983 photos

It is indeed a G60 RV of 1966 vintage ! yes it was looking a bit sad when I got it,it looks like some one may have converted it to marine use at some stage by taking off most of the fins,I think it may also have a later piston fitted as it should have two rings not one ? anyway it only cost me a fiver, worth it for the carb alone !

p.jpg

jeff2wings25/10/2019 18:44:04
avatar
807 forum posts
1983 photos

A couple of pictures of the G 60 being machined for replacement fins

img_20190913_133528.jpg

img_20190913_134943.jpg

JACK11/11/2019 19:52:56
avatar
80 forum posts

very interesting thread this,l too have just taken possession of a project engine from ebay….cameras on the blink, but will post some pics asap---this engine is a petrol twin based around a pair of cylinders from crrc 50 size engines,the crankcase has been machined from billet alloy,and the standard of machining looks really good,the inlet ports have been blanked of with custom made plates,and a walbro carb sits on a machined in mount.....l am assuming that the internals I e crankshaft are custom madembut l suspect that the conrods and pistons will be from the original engines......the only markings on the engine are on the rear of the crankcase,where the letters"ftl" appear,it is a big chunk of engine,anyone know anything about it??,its a professional job,done by someone with a fair bit of knowledge,hopefully l can get it to run,but something is nagging at me about it,cant put my finger on it though,l am not really an engine man,but have dabbled in model engineering,any info will be most welcome.

Robin Colbourne11/11/2019 20:36:13
avatar
582 forum posts
17 photos

Jack, It sounds a bit like the Quadra twin our department at RAE Farnborough had made for a UAV in the 1980s. It used two Quadra 50 cylinders.

JACK12/11/2019 19:17:04
avatar
80 forum posts

robin,that does sound very similar,my concern is the fuel mix transfer to the combustion chamber from the crankcase,the crrc 50 singles have the carb mounted direct to the cylinder,so l cant quite see how the fuel mix can transfer from the c/case to the transfer port and thence to the combustion chamber....l plan on doing a partial strip down for inspection,so hopefully all will be revealed,if it runs as good as it looks then l will be a very happy bunnysmiley

Robin Colbourne12/11/2019 20:09:19
avatar
582 forum posts
17 photos

Jack, on the single cylinder engine, the bottom of the piston acts as the valve controlling flow from the carburettor into the crankcase. On the twin, I suspect a reed valve between the carburettor and crankcase does the job, in the same way as on a Cox Babe Bee 049.

When the pistons are moving apart (going up the cylinders), there will be a negative pressure in the crankcase, which opens the reed valves allowing the air fuel mix in. When the pistons move towards each other (descending in the cylinders) the reed valve shuts, squeezing the fuel/air mixture up the transfer ports on each cylinder and into the combustion chambers.

JACK13/11/2019 14:16:57
avatar
80 forum posts

robin,thanks for that,what l am not sure of is whether the transfer ports are actually open to the crankcase as the cylinders are from a single cylinder engine,but,as l say,l cant see someone putting so much work in to the project with out having addressed that question,my camera should be fixed soon so l will post some pics,plus l plan to take the cylinders off for a look see at the internals

JACK28/11/2019 21:18:35
avatar
80 forum posts

regarding my posts on the twin l recently bought,l am not really sure what size prop to use on it,as l said,it appears to be around 100cc,using a pair of crrc piston/cylinders,each of around 50cc,giving a total of 100cc,so it will swing a fairly big prop,l intend using an rxcel ignition set,so can anyone give me an idea as to prop size?,not really a petrol head so this is likely a daft question!!!.....jack,

Denis Watkins28/11/2019 21:54:29
4421 forum posts
112 photos

26 x 10 - 12, 28 x10

JACK29/11/2019 19:47:47
avatar
80 forum posts

thanks dennis!!

jeff2wings10/01/2020 20:59:40
avatar
807 forum posts
1983 photos

So over the Christmas hols had a sort out in the workshop,starting with a second shelf for engine projects

img_20191014_205238.jpg

still plenty to do smile p.I also completed some rebuilds for other people

img_20191013_152631.jpg

1947 Owat

img_20200110_195210.jpg

Enya 45

img_20200110_195154.jpg

and a Meteor 61

img_20200110_195245.jpg

jeff2wings25/02/2020 19:09:57
avatar
807 forum posts
1983 photos

Not having anything much to do this afternoon decided to sort out a couple of Enyas

img_20200225_105935.jpg

oh the perils of castor ! both engines locked up

img_20200225_183814.jpg

but not any more

img_20200225_183839.jpg

ready to give more years of good service

All Topics | Latest Posts

Please login to post a reply.

Latest Forum Posts
Support Our Partners
CML
Sussex Model Centre
electricwingman 2017
Slec
Sarik
Advertise With Us
Latest "For Sale" Ads
Has home isolation prompted you to start trad' building?
Q: The effects of Coronavirus

 Yes - for the first time
 Yes - but Ive bashed balsa before
 No - Ive existing projects on the bench
 No - Im strictly an ARTF person

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E!