Mk 11C Hurricane winter build

Thanks Dave for the pic and VID

Wow... Certainly looks impressive both in size and looks. Jealous!

Also jealous i didn't see the maiden but i'm not sure my nerves could have stood the dead stick landing. We are lucky to enjoy the skills of JT for such events.

Have you established the cause of the engine stopping - for what its worth, I've been doing a bit of research into DLE running issues recently and there are quite a lot of posts on the US websites relating to "lapping" the reed valve faces. Also an article in this months RCM&E where the author also describes the process of lapping the reed petals as well. I don't know if this was a historic issue or related to current engines but thought it might be worth sharing info for all petrol heads.

With this in mind, i have stripped the reed assembly on my long standing troublesome Mintor engine. I did find some fretting on the edge of the reed petals (on my engine they are steel) so i have cleaned and lapped them and will shortly reassemble the engine for testing.

It didn't stop dead, initially it faded so I throttled back assuming it was overheating and set up for an emergency landing, then as soon as I tried to throttle up again it stopped immediately!! Definately gave me a few worrying moments and with the strong Northerly, I was relieved to see it clear the downwind hedge, just couldn't make the field.

It definately leaned out as it would idle but not throttle up, so I suspect it got hot. It had been running well before though for at least 6 or 7 minutes. If it were me I would open up the airflow a little and ritchen a bit on the top end.

Because I'm not an engineer and also do not have petrol engines...I'll stick my neck out and ask "what's lapping?" That'll save embarrassment for anyone who does own a petrol engine but was too shy to ask.

That's very interesting kevin will have a look at that.I'm sure my problems were, brand new engine,a tad on the lean side and could do with some ducting in the cowl to force more cooling air over the fins and possibly open up the exit to allow the hot air to escape quicker.
Anyway the couple of scratches on the underside of the wing have been repaired and a new radiator has been made ready for fitting.I'm putting the hurricane on the back burner for a few weeks and get my Sukhoi ready and go and do some flying for a change instead of bashing balsa in the workshop

MikeSeale wrote: Because I'm not an engineer and also do not have petrol engines...I'll stick my neck out and ask "what's lapping?" That'll save embarrassment for anyone who does own a petrol engine but was too shy to ask.

As your not and engineer and don't operate petrol engines, just think of lapp dancers and sleep well tonight

but seriously - here is one of the links i was referring to

www.grosbeakrc.ca/hangar/pulse125/modifications/lapping.html

Lapping, mechanics and fitters do the lapping, engineers inspect the result

Referring to Kevin's lapping info and the informative URL it so happens that the April issue of RCM&E has an article by Brian Winch the engine guru from OZ that refers to lapping of carburettor reeds especially glass fibre ones that seem to be the case in the URL piece. The need arises apparently from the reeds being punched out and thereby having a microscopic burr which causes poor start and running in some cases (pages 89&101). In such a case Brian advises using at least 1200 with a preference for 5000 wet and dry abrasive paper and carefully lapping the reeds on a glass surface for flatness. That is not detracting from the URL article however one would expect that gaskets should effect the necessary seals in the case of the casing as discribed in the URL piece whereas the reeds are the actual metering device of the gas/oil/air mix directly into the manifold.

An article well worth a close read for all petrol heads. :whistle:

Photos