Ronos Posted May 8, 2020 Share Posted May 8, 2020 Hi all, a quick on for you, Would a carburettor from a OS40FS Surpass fit onto a earlier OS40FS, the one with the spring on the needle. Quote Link to comment Share on other sites More sharing options...
Jon H Posted May 8, 2020 Share Posted May 8, 2020 i think so I have both types but need to dig out the surpass to confirm. I will get back to you later Quote Link to comment Share on other sites More sharing options...
Ronos Posted May 8, 2020 Author Share Posted May 8, 2020 Posted by Jon - Laser Engines on 08/05/2020 16:49:50: i think so I have both types but need to dig out the surpass to confirm. I will get back to you later Thanks Jon, much appreciated. Quote Link to comment Share on other sites More sharing options...
Jon H Posted May 8, 2020 Share Posted May 8, 2020 Just checked and they look identical to me Quote Link to comment Share on other sites More sharing options...
Ronos Posted May 8, 2020 Author Share Posted May 8, 2020 Posted by Jon - Laser Engines on 08/05/2020 17:54:41: Just checked and they look identical to me Thanks Jon, do you think if I just ordered the needle rather than the whole carb, it would fit into the carb body. Quote Link to comment Share on other sites More sharing options...
Doctor Chinnery Posted August 1, 2020 Share Posted August 1, 2020 I have recently revived my old OS40FS - quite old really, last times it flew was in a Radio Queen 30-35 years ago. The poor old thing was seized solid. Anyway, after anointing with WD40 and then spending the best part of a couple of weeks immersed in stale fuel (a ziplock freezer bag does the job) the old FS cleaned up a treat and after thorough flushing and gentle then increasingly more vigorous turning over without a plug etc etc I started it in my test stand and the years of neglect fell away - easy start as per the handbook with a vigorous reverse flick, as long as you use a biggish (11"-12") prop. Still throttles well with that nice slow tickover I remember. Now - advice please: Can I, and/or should I use my electric starter to start this lovely old four-stroker, or should I stick to the large prop':reverse flick technique? Also - the crankcase breather tube, the installation I have in mind for the OS neccessitates the use of an 8 inch length of fuel tube to drain the unburnt oil out of the airframe - seem to remember something about the breather tube length to be critical, but can't find anything in the literature. Ideas anyone? Thanks. Edited By Doctor Chinnery on 01/08/2020 20:45:54 Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 1, 2020 Share Posted August 1, 2020 If the engine was gummed up with castor i recommend you strip it down and change the bearings. It might feel smooth, but its likely the balls in the bearings are still stuck and are skidding in their races. Eventually the bearings will breakup and ruin the engine. As its only an hour job to rebuild it i strongly recommend you swap out the bearings. Also i know its considered common practice, but never use WD40, 3in1, petrol or cellulose thinners to clean up an engine. Its not good for them. As for the rest, electric is fine as long ass you are sure its not flooded, the backflick works too. I also would not be too worried about the breather. If OS say 8 inch is fine go for that, although truthfully thats pretty long! Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted August 1, 2020 Share Posted August 1, 2020 What's wrong with WD40 please ? Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 1, 2020 Share Posted August 1, 2020 Posted by john stones 1 on 01/08/2020 21:26:44: What's wrong with WD40 please ? Its not actually a lubricant, its a water dispersant (hence WD in the name) and its not going to do your engine any favours if its floating around the crankcase. 3in1 is acidic, petrol wont dissolve castor and will eat most of the seals in a glow engine, cellulose is for paint...not sure why folk use it for engines! Old fuel is fine but it wont save castor clogged bearings. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted August 1, 2020 Share Posted August 1, 2020 Cheers, I only use to loosen things, It doesn't eat O rings or seals then ? Rest I don't use. Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 1, 2020 Share Posted August 1, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Doctor Chinnery Posted August 2, 2020 Share Posted August 2, 2020 ThankYou for the advice Jon - I guess it's going to be another of those "you're never too old to learn" jobs (I'm glad I'm only 78!). Quote Link to comment Share on other sites More sharing options...
paul d Posted August 2, 2020 Share Posted August 2, 2020 Along time ago I seem to remember Brian Winch talking about wd40, apparently it will attack phosphor bronze bushes. Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 2, 2020 Share Posted August 2, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 2, 2020 Share Posted August 2, 2020 Posted by Doctor Chinnery on 02/08/2020 01:34:56: ThankYou for the advice Jon - I guess it's going to be another of those "you're never too old to learn" jobs (I'm glad I'm only 78!). No problem. For the cost of a few quid in bearings and a little of your time its well worth it. Sure you might get away with it as is, but equally you might not. Then you end up with a mess like in the photo below. Quote Link to comment Share on other sites More sharing options...
Doctor Chinnery Posted August 3, 2020 Share Posted August 3, 2020 Well, if I needed any further incentive to replace the bearings, you've provided it Jon! As far as I can see all I require will be the front and back bearings - Model Fixings should have them in stock - I might treat myself to a decent set of metric Allen Keys from the same source while I'm at it. Now, where do I find a step-by-step guide to to the job, ideally specific to this individual motor rather than the generic videos on YouTube? ( I suppose I could try a ouijah board or in extremis a medium to have a word with The Wizard of Oz ! ) 'Cos I don't want to turn this old favourite into an inconveniently shaped paperweight. ☹️ Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted August 3, 2020 Share Posted August 3, 2020 Take good photos As you go I do, so As I find my way back Quote Link to comment Share on other sites More sharing options...
Peter Christy Posted August 3, 2020 Share Posted August 3, 2020 Jon: I keep a Kilner jar full of red diesel for un-gumming old engines, a tip I got from an old friend (an engineer by trade) years ago. He also recommended contaminated diesel - often cheaply available from garages from people who have topped up their diesel car with petrol! Any comments on its suitability? -- Pete Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 3, 2020 Share Posted August 3, 2020 Its a pretty simple job. backplate and head off, cam cover plate off, liner out, mark position then piston/conrod out (can be a fiddle), cam shaft out (photo position first), crank out with a few hammer taps, and then its time to toast it up with a heat gun or similar to get the bearings on the move. One they are out its the same job but backwards! Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 3, 2020 Share Posted August 3, 2020 Posted by Peter Christy on 03/08/2020 12:48:36: Jon: I keep a Kilner jar full of red diesel for un-gumming old engines, a tip I got from an old friend (an engineer by trade) years ago. He also recommended contaminated diesel - often cheaply available from garages from people who have topped up their diesel car with petrol! Any comments on its suitability? -- Pete As glow engines are designed for methanol anything petroleum based risks damage to seals etc. Equally, castor is not soluble in petrol/diesel so wont actually dissolve. Quote Link to comment Share on other sites More sharing options...
J D 8 Posted August 3, 2020 Share Posted August 3, 2020 Red diesel and white road diesel are the same except for the red/pink dye that indicates it is for non road use only and has less tax imposed on it. Quote Link to comment Share on other sites More sharing options...
Foxfan Posted August 4, 2020 Share Posted August 4, 2020 So, Jon, what is a good solvent/cleaner for castor in your experience? Cheers,] Martin Quote Link to comment Share on other sites More sharing options...
Jon H Posted August 4, 2020 Share Posted August 4, 2020 Posted by Foxfan on 04/08/2020 13:51:43: So, Jon, what is a good solvent/cleaner for castor in your experience? Cheers,] Martin There isnt one. Take it to bits, throw the old bearings away and replace. Flush it out as best you can with old fuel and a toothbrush if you want and then use synthetic oil after that. Alternatively, change the bearings, leave all the castor gunge inside and just keep running the engine. After a few gallons it will have flushed it all away. Just dont stop using the engine as the residual castor will gum up the works again. There are some products that can clean up the outside of the engine, but you dont want to be squirting them inside. Quote Link to comment Share on other sites More sharing options...
Doctor Chinnery Posted August 5, 2020 Share Posted August 5, 2020 Posted by Jon - Laser Engines on 03/08/2020 12:48:50: Its a pretty simple job. backplate and head off, cam cover plate off, liner out, mark position then piston/conrod out (can be a fiddle), cam shaft out (photo position first), crank out with a few hammer taps, and then its time to toast it up with a heat gun or similar to get the bearings on the move. One they are out its the same job but backwards! Sounds easy if you've done it a few/dozen/hundred times but to an engineering virgin: intimidating is the term that comes to mind, 'specially if despite much marking and photographing I get the piston & liner or worse (probably) the cam shaft wrongly aligned when putting it all back together. Shame there don't appear to be Hayes or For Dummies publications on the subject. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted August 5, 2020 Share Posted August 5, 2020 "Now, where do I find a step-by-step guide to to the job, ideally specific to this individual motor rather than the generic videos on YouTube" The OS motors share a common design with only minor variations, as far as I know. It took me about 45 minutes last time I changed bearing on a OS four stroke - I think I used a video showing a 48 Surpass as a guide for a 70 Surpass. The basic construction is common, there may be small differences but the method of aligning the cam and getting the piston/conrod out is common (I think). Anyway. Dave MacIntyre's channel has lots on OS four strokes... 40 Surpass being part disassembled (head removed): **LINK** 40 Surpass, with the liner and cam out **LINK** pt2 of the above, annoyingly does not show piston removal **LINK** One showing piston pin removal **LINK** 40 Surpass reassembly including popping in new bearings: **LINK** An older video, bit jerky, on a 52FS, a full disassembly: https://www.youtube.com/watch?v=S_HrTCCO-GY and reassembly part 1 https://www.youtube.com/watch?v=2WO9LRBIc_g&t=41s part 2 https://www.youtube.com/watch?v=8FoLT8VjKqE Edited By Nigel R on 05/08/2020 11:32:51 Quote Link to comment Share on other sites More sharing options...
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