tomarnold Posted November 29, 2013 Share Posted November 29, 2013 I couldn't get my motor to start the other day. I traced the problem to the plug, replaced it and it fired up straight away. However, as I was testing it in the shed I had taken the prop off. It ran fine and revved up fine but wouldn't idle, even once it had warmed up. I haven't changed anything other than the plug and taking the prop off. I wondered if perhaps the prop's flywheel effect would help the engine tick over. Would you expect your motor to idle without the prop on? As soon as I get a chance I'll fire it up outside with the prop, which should answer my question, but in the meantime I am intrigued to find out your views. Quote Link to comment Share on other sites More sharing options...
gordon_dunn Posted November 29, 2013 Share Posted November 29, 2013 Most manufacturers recommend you don't start or run the engine without the prop.... Yes it acts as a flywheel, and without it the engine can 'race' and cause damage. Depending on your machine, your warranty may be void now. Quote Link to comment Share on other sites More sharing options...
tomarnold Posted November 29, 2013 Author Share Posted November 29, 2013 Oops, won't be doing that again then. I'm not too worried about the warranty though - I'm fairly sure mine ran out well over 10 years ago! Quote Link to comment Share on other sites More sharing options...
notch Posted November 30, 2013 Share Posted November 30, 2013 Its only really a problem if your engine is running lean. Without a load (prop) and normal mixture, most two strokes cannot achieve anything approaching max RPM. They bog down and fire every other cycle (four stroking), and then every 3rd cycle etc etc. Quote Link to comment Share on other sites More sharing options...
Dariuszk24 Posted November 30, 2013 Share Posted November 30, 2013 radne has clutch and forced head cooling by flywheel fan,nothing happened but you need to be carefully do not "turn over"engine without load(prop),if this would happens you notice that in some moment(new engine) :(O Quote Link to comment Share on other sites More sharing options...
stuartasutherland Posted November 30, 2013 Share Posted November 30, 2013 I have a Thor 200 and always start and warm up without a prop. It has a clutch so doesn't matter and if there is no prop on, I can't chop my hand off! Sent from my iPad using PMC Forum mobile app Quote Link to comment Share on other sites More sharing options...
Trickyh Posted November 30, 2013 Share Posted November 30, 2013 Totally agree with Stu. Same Thor 200. Run it at idle (1200rpm max) without the prop on to get some warmth into it and bubbles out of the system. Much safer There is a chance you could do some damage if you revved the nutz off it, but summat would have had to have fallen off for it to do that, then i'd be double glad I haven't got the prop on it! Some engines (Flymec for example) need to be idled for at least 10mins to get their water cooling circulating... (they don't have a pump) I'd love to know how you would invalidate a warranty?? Unless someone grassed you up of course! Quote Link to comment Share on other sites More sharing options...
Trickyh Posted November 30, 2013 Share Posted November 30, 2013 Oh, and to answer your question. It might not idle without a prop on.. Belt driven, clutchless jobs ie: Moster do use the prop as a flywheel, so it might idle like a bag of spanners.. (if at all) Quote Link to comment Share on other sites More sharing options...
tomarnold Posted December 1, 2013 Author Share Posted December 1, 2013 Thanks, that puts my mind at rest a bit. My motor is clutchless and belt driven. Hopefully off flying tomorrow, so will have to wait and see... Quote Link to comment Share on other sites More sharing options...
tomarnold Posted December 1, 2013 Author Share Posted December 1, 2013 I just got home, so I took the motor out in the garden, fitted the prop, and it fired up and ran beautifully. Hooray! Lesson learned though. Now I just have to try and figure out why my tiny tach (I think that's what it's called) rev counter isn't working. (edit - turned out to be a broken wire. Nice easy fix, I love those!) Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.