Roger Jones 3 Posted January 25, 2021 Share Posted January 25, 2021 Posted by GrumpyGnome on 25/01/2021 11:25:49: In my opinion, I am not sure all petrol engines are crude or converted chainsaw engines tbh ..... seems to definitely be a growth area and manufacturers are responding. Similarly, not all OS clones are bad - I have had a number of SC 2 and 4 strokes that were excellent........maybe I have been lucky and had all good ones whilst others have been unlucky and had all bad ones..... OS engines, and spares have always been, in my opinion, excessively high but if people are willing to pay, why would any manufacturer one not keep prices at that level. GG Despite what Nigel R says the price of OS engines has nearly doubled in recent years. An OS 25 is now £200 whereas a basically similar OS 46 is £137, which is crazy. I can easily afford it but I choose not to. It's Laser for me from now on. Re SC, I give everything two chances. Both my two SC engines an 18 and a 61, have been useless, mostly due to the leaky carbs where the throttle barrel fits so loosely they won't even stop due to air leakage. No more SC's for me. Quote Link to comment Share on other sites More sharing options...
chris larkins Posted February 4, 2021 Share Posted February 4, 2021 I am neither pro glow or pro petrol, I have both and fly both and I own several Lasers and a couple of Saitos. A couple of years ago I converted an SC 1.20 to run on petrol, firstly using the original glow carb but as Martin stated earlier it was far too sensitive. I then bought a cheap RCGF carb and have had good success with it, having probably 40-50 flights with no issues other than it getting too hot initially. I fitted baffles in the cowl and added a lip to the outlet underneath the cowl and it has been ok ever since Why did I go to the bother of converting it to petrol? Mainly to see if I could...... I made some of the parts myself but did buy a machined carb adapter and adapter ring, since then I have copied and made these items using my lathe/mill for just a couple of pounds, total cost for the conversion was around £100 but I reckon I could do another for around £60 by making the machined parts myself and buying an inexpensive ignition unit & carb. So far the CONS have been...... the cost of the conversion slight loss of power compared to when it was glow (not an issue on a Turbulent that just cruises around) another battery to charge PRO's - low fuel cost initially and miserly consumption complete lack of exhaust residue the extra battery makes starting easy, just switch on and spin the prop after initial setup no tweaking of needles, not even the infamous nose-up check absolutely reliable running & tick-over - finger crossed that I haven't jinxed it Would I do it again ? - probably, not sure when though Link to video of it running HERE Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 4, 2021 Share Posted February 4, 2021 Posted by chris larkins on 04/02/2021 00:23:00: I am neither pro glow or pro petrol, I have both and fly both and I own several Lasers and a couple of Saitos. A couple of years ago I converted an SC 1.20 to run on petrol, firstly using the original glow carb but as Martin stated earlier it was far too sensitive. I then bought a cheap RCGF carb and have had good success with it, having probably 40-50 flights with no issues other than it getting too hot initially. I fitted baffles in the cowl and added a lip to the outlet underneath the cowl and it has been ok ever since Why did I go to the bother of converting it to petrol? Mainly to see if I could...... I made some of the parts myself but did buy a machined carb adapter and adapter ring, since then I have copied and made these items using my lathe/mill for just a couple of pounds, total cost for the conversion was around £100 but I reckon I could do another for around £60 by making the machined parts myself and buying an inexpensive ignition unit & carb. So far the CONS have been...... the cost of the conversion slight loss of power compared to when it was glow (not an issue on a Turbulent that just cruises around) another battery to charge PRO's - low fuel cost initially and miserly consumption complete lack of exhaust residue the extra battery makes starting easy, just switch on and spin the prop after initial setup no tweaking of needles, not even the infamous nose-up check absolutely reliable running & tick-over - finger crossed that I haven't jinxed it Would I do it again ? - probably, not sure when though Link to video of it running HERE Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 4, 2021 Share Posted February 4, 2021 If you want to run glow use a glow engine. If you want to run petrol use a petrol engine. Quote Link to comment Share on other sites More sharing options...
chris larkins Posted February 4, 2021 Share Posted February 4, 2021 Posted by cymaz on 04/02/2021 19:32:43: If you want to run glow use a glow engine. If you want to run petrol use a petrol engine. It used to be a glow engine, it's now a petrol engine, and it could become a glow engine again...... Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 4, 2021 Share Posted February 4, 2021 Posted by chris larkins on 04/02/2021 19:47:21: Posted by cymaz on 04/02/2021 19:32:43: If you want to run glow use a glow engine. If you want to run petrol use a petrol engine. It used to be a glow engine, it's now a petrol engine, and it could become a glow engine again...... With I have only a limited amount of knowledge with engines but the burn rate of glow and petrol are very different. Would you need different engine timings and ports to get the correct burn ?? Quote Link to comment Share on other sites More sharing options...
J D 8 Posted February 4, 2021 Share Posted February 4, 2021 On one of my last visits to the club strips a fellow club member jokingly said I was going to have an expensive day as we assembled our craft. His a 30cc petrol aircraft and mine a 90 4st glow Katana. At the end of the session I had used over half a gallon and he he had used very little fuel, but that was because his engine would not start. Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 4, 2021 Share Posted February 4, 2021 I have to admit, Chris's effort is probably the best i have seen and it sounds really good. The problem is, its not guaranteed to work that way. If every conversion worked as well as that it would be fine, but its probably the only video i have seen of a petrol conversion that i would actually accept as working correctly. Cymaz's point is simple. If you want a glow engine that is guaranteed to work, buy one, and the same for petrol. Trying to turn one into the other is not guaranteed to work and it is why i dont recommend it for Laser's. In fact i have two failed petrol conversions on my repair bench as i write this waiting for me to convert them back to glow. I understand the reason people convert though. Petrol engines, 4 stroke especially, are not cheap and their cost completely nukes the savings in fuel cost. So conversion seems the logical choice. The problem is, is far from guaranteed you will have your cake and eat it. More than likely you will spend on the conversion and then end up with something expensive getting broken. Its not worth the risk. If you want petrol, buy petrol. 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.
Note: Your post will require moderator approval before it will be visible.