Irvine .40 needs tuning I think...

[Mathew Brooks]

Hi guys, me again. I have a ripmax 40 with an irvine 40 now I can get it running and revving but after two minutes or so I still can take it to max power without it cutting out. Is this normal? Do I have to wait longer for it to warm up etc. or does it need tuning slightly?

Thanks. Mat

[Johnny Kirkham]

Mat can you give more info on how the engine cuts out? ie are you on tickover and when you open up it cuts out?? ......and no its not normal

Johnny

[Mathew Brooks]

It runs on tick over all ok but when it goes from just above tick over to full power it stalls like pretty much instant...

[Former Member]

[This posting has been removed]

[Mathew Brooks]

Ok. I got the plane second hand last weekend and was debating over changing the glow plug as I don't know the history of it tbh. The needle is screwed all the way in and then back two full turns. Does this help. Not sure about the fuel as its what's left in the tank when I got it. The guy I got it from is a mad moddeler and had over 70 planes so I'm sure it's the right kind but not 100% sure.

[GrahamC]

Is is a new engine? If it does look new, has it been run in? You might expect this from an engine that is still too tight.

[kc]

I s the engine really reving? Turning the needle in one click at a time ( leaning it ) should increase the revs until it really peaks- at this point you can hear the note changes. Does it do this?

[Mathew Brooks]

The engine looks fairly old in my opinion. Kc, I will try this tomorrow as batteries on charge. Should I wind in the leaning knob all the way in to start with, then wonderful it out gradually, or the other way round?

[crispin church]

was you getting a lot of oil / smoke coming out

wind needle all way in then turn it out 2 may be 3 turns

if you got a taco then use it if not buy one or bye ear full flat revs turning in the needle click at a time untill the revs stop going up and then wind it out 1/2 turn

then lower the revs and try going from low to high revs at servo speed does it cut out

if so low needle needs changing

are you running 10" prop on it

[kc]

Dont lose the existing setting! If the engine runs at the present setting then start up, then try one click at a time leaner ( closing/ winding in ) probably the revs will increase. run for a half minute and try another click leaner. Keep going leaner until the engine starts to falter when you put the nose up at 45 degrees, then richen by 2 or 3 clicks. ( take care with an engine really reving and lifting the nose - make sure you have the wing on firmly, have a good grip and a knowledgable helper to close throttle- its a two man job)

I think we said earlier to go along to a club and get some advice. Ask who is for the best person with engines. An experienced glow man will get the engine right in minutes or tell you if there is something really wrong. They will have a spare glow plug to try and fuel of known quality available. They will ( should) also advise on safety whilst running engines which is important. Be aware of frequency control before you switch on when on 35Mhz.

[Glyn R]

My Irivne engines only need one and a half turns out on the main needle. This is almost right for all conditions. I have 3 and they all the same.

Edited By Glyn R on 01/06/2013 22:38:29

[Martin Harris - Moderator]

I would agree wholeheartedly that it would be best to get someone experienced to show you how to adjust it - and more importantly, show you the scars where they (or one of their clubmates) has learnt the dangers of operating model engines the hard way. I would put money on someone at any busy club bearing the scars of a past encounter so don't underestimate the dangers and try to learn good practises from the start.

If you really can't get help at a club then this is what you need to do.

First, restrain the model with, at the very least, a strap round the tail attached to something immovable or driven firmly into the ground. Have a clear space to move around the model and ensure there are no children or pets around. Keep everyone behind the prop if you have any assistants/onlookers. When you start the engine get up carefully, move behind the propeller and only then remove the glow and make any high end adjustments, Do not attempt to adjust the low end (more to come on that) with the engine running. Although it's best to keep onlookers away, do make sure that assistance is within earshot in case the worst happens.

Start with the main needle 2 1/2 turns out - this will be too rich but it's a good starting point. Once running, remove the glow. Remember to do this from behind the prop - do not reach over the prop to remove it!

If it cuts instantaneously when you open the throttle slightly then the low end needle is set too lean - or there is a blockage from a foreign body or congealed oil.

You'll see a screw head on the opposite side to the main needle which is the idle mixture adjustment (which actually does most of the metering up to 2/3 or more open). Unscrew it quarter of a turn at a time (stop the engine each time) until the engine doesn't cut when you open the throttle. When you have it running at full throttle, screw the main needle in slowly to lean the mixture until the engine peaks - then richen it 2 or 3 clicks.

If it will now transition well from idle through to full throttle that's great but if it cuts or hesitates you have some more tweaking to do. If it cuts dead it's too lean so unscrew the idle screw by quarter turns again until the engine picks up smoothly. If it's too rich the revs will drop significantly as you remove the glow and the engine will splutter a bit and then pick up as you open the throttle - screw the idle needle in to correct this.

When you have set this, repeat the high end setting and recheck as the 2 adjustments will have an effect on each other, until it's behaving correctly.

Once again, please use the utmost care and respect the fact that you have, effectively, an unguarded circular saw an inch or so from your fingers.

Once you have the engine sorted I suspect you'll be wanting to fly. Again, a club is the best place to do this. Wherever you fly it must be suitable and away from people or habitation - and insurance is a very sensible precaution.

If you're tempted to fly alone without help or previous experience you will, in all probability, get disorientated and crash even if you know the theory. It isn't impossible to learn by yourself (a simulator can help) but is likely to end in disappointment. I have taught a good number of people (even very experienced full sized pilots find great difficulty at first) and all would have crashed several times without intervention before they come off the buddy lead.

Edited By Martin Harris on 02/06/2013 02:31:47