cymaz Posted April 17, 2020 Share Posted April 17, 2020 Jon ...found the video. I will post it to you by pm. I’m not going to post it on the forum, the mods would have an fit ! Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted April 17, 2020 Share Posted April 17, 2020 well done from me Jon,enjoyed watching your doing it your way..... ken anderson...ne...1.... his way dept. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 17, 2020 Author Share Posted April 17, 2020 Posted by cymaz on 17/04/2020 08:40:08: I’m sure I’ve seen a piece on drifting bearings out by forcing in strips of cloth through the ID using a hammer and rod. Ha! great video, cant fault his enthusiasm! In my case though, im not sure there would have been enough room to do that as the bearing is near flush with the housing and my bearing is teeny!. In his case...it would have been quicker to drill through it and tap it out from the back :P Edited By Jon - Laser Engines on 17/04/2020 09:47:14 Quote Link to comment Share on other sites More sharing options...
cymaz Posted April 17, 2020 Share Posted April 17, 2020 Also he’s got a shielded bearing. It’s one I’m going to remember. The grease must give just enough force to push the cloth under the bearing race. BTW, if anyone else wants the video I will send it to them pm. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted April 17, 2020 Share Posted April 17, 2020 The last time I got a cam bearing out I used candle wax melted into the bore of the bearing and a close fitting pin punch. IIRC that was when I merged an older SC91 with some newer parts and discovered that not all 91 cam bearing covers are the same depth even though they contain the same size bearings. Rustoration - sums it up, some surprisingly ratty looking engines will run really well just so long as the piston rings and bore aren't too far gone. On the other hand some ABC engines don't need much wear to really make a difference. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 17, 2020 Author Share Posted April 17, 2020 As soon as i saw that the liner was ok and i was able to rescue the piston ring the whole thing had potential. If those two things were toast i would not have bothered and had the bearing fits gone out the window i would not have bothered either. Enough of the important parts were in good enough condition for it to have a chance. I did have another little go at the exhaust valve and its improved a bit but there is still damage to the seat and the seal seems to loose the plot once the head is tightened down so its likely the head is distorted. i am told this is common on ASP engines. Anyway, its better than it was and i refitted the pushrod tubes with, admittedly, an O ring bodge that saves me having to wait for them to turn up. Its going to be fine for now and will help protect it from dirt. I can fit the proper parts later. I will probably cover the hole in the crankcase with some ali tape as a stop gap until i have time to make a little plug. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted April 17, 2020 Share Posted April 17, 2020 Well that runs ok! (although I note you gave up and used a starter The throttle response from these basic airbleed carbs always impresses me. I find similar with the old FP two strokes and their simple carbs. Quote Link to comment Share on other sites More sharing options...
Former Member Posted April 17, 2020 Share Posted April 17, 2020 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
J D 8 Posted April 17, 2020 Share Posted April 17, 2020 Hi Jon, I have an ASP 70 that was given to me along with the shed of a puppeteer it was in. Nowhere near as poor condition as yours. Piston seal is good, both valves seal ok but I just could not get it to run more than a few phuts. Turning it over while dribbling thin washing up liquid over the head showed it was not sealing. Tried one shim, two shims, no shim but nothing helped. Looking at the head one feels it could do with another head bolt on the other side of the glow plug but I think the exhaust port is in the way. Well distorted I recon. Cheers John. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 17, 2020 Author Share Posted April 17, 2020 Posted by Nigel R on 17/04/2020 14:07:28: Well that runs ok! (although I note you gave up and used a starter The throttle response from these basic airbleed carbs always impresses me. I find similar with the old FP two strokes and their simple carbs. yep, i cant get the fuel up top due to all the leaks so went electric. I was also really happy with the throttle, its quite astonishing how well it works when you consider both how simple it is and how ruined! JD8. Thats unusual, i wonder if the head has a crack in it as i would expect it to seal round the liner at least. DO you still have it? It might be interesting to fiddle with it. As for the 40 i ran it up again following the little tweaks today. Compression is better but it still leaks a bit. Im not worried about it though as it runs well enough and as i am only going to fit into sometime docile and floaty the loss of a bit of power wont matter. That said, i dont think i have much power missing as it hit 10400 as a peak and held it for a good while before it got hot and fell back to 10000. Its not easy to tune as the leaky carb means just touching the needle changes the tuning so its a tweak and hope job. Again, this wont matter for my intended use. All i need now is a model for it. What shall we go for? hmmmmm Quote Link to comment Share on other sites More sharing options...
Nigel R Posted April 17, 2020 Share Posted April 17, 2020 As a dodge can you use a remote needle? Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted April 17, 2020 Share Posted April 17, 2020 Years ago I had mine in a Stanley Apprentic, the 60" wingspan cardboard high wing trainer, flew it really well. I then built a 52" span bipe and put a Webra Speed 40 with a 10 x 6 in it, performance was poor, especially getting away, I changed the prop to a 12 x 5 and it was better but the Speed 40 wasn't happy. The OS40FS ran really well on a 12 x 5 so I swapped the engines out and it was a better match. OS ended up in a Sig Clipped Wing cub, 56" span, a great combination. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 17, 2020 Author Share Posted April 17, 2020 i could use a remote needle, but it works well enough so again its not a big deal. Frank, i was wondering about a 12x5. I need to go back to my parents house and rummage in the garage as its been a long time since i used a prop smaller than about 16 inch and i dont have any to hand Quote Link to comment Share on other sites More sharing options...
Shaunie Posted April 17, 2020 Share Posted April 17, 2020 I have one of these but in far better condition. It probably last ran eight years ago, nevertheless despite the condition I may replace the main bearings as I’ve had two engines destroy their main bearing cages recently (RCV91 and a YS110). It’ll be nice to get it going as I’ve got a Flair Avro 504 for it to go in and I have a Fleet FM radio for it. All vintage of the same era. shaunie. Quote Link to comment Share on other sites More sharing options...
J D 8 Posted April 18, 2020 Share Posted April 18, 2020 Posted by Jon - Laser Engines on 17/04/2020 15:53:34: JD8. Thats unusual, i wonder if the head has a crack in it as i would expect it to seal round the liner at least. DO you still have it? It might be interesting to fiddle with it. I still have it, been in a box in bits for over a year. Will dig it out and have another go. Not checked for a cracked head. With the head on there was just no compression. With it off putting my palm over the top of the cylinder tells me the piston seal is fine Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 18, 2020 Author Share Posted April 18, 2020 Shaunie, that sounds like a fun project. I dont know what i am going to do with mine just yet but i have had my eye on the super flying model se5a which i think it would be well suited. In the short term i might just find a random airframe i can nail it to for some air testing. JD8, that could still be the valves. I was tasked with trying to recover an ASP 180 and the exhaust valve just would not seal. That said if you can see bubbles round the base of the head clearly that is another issue Quote Link to comment Share on other sites More sharing options...
Martin Arnold 1 Posted April 18, 2020 Share Posted April 18, 2020 Have found on a number of SC/ASP four stroke motors when I was trying to get the valves to seal, that the valves were a good seal on the bronze seat but the leak was between the bronze insert and the head casting. Quote Link to comment Share on other sites More sharing options...
J D 8 Posted April 18, 2020 Share Posted April 18, 2020 Hi Martin, It could be that is the problem with mine. As in my post above I remember seeing bubbles forming as I turned the motor over. That was over a year ago and may well been from the rocker cover and not the head/ cylinder. Did you find any way to sort the seat/head leek? Cheers, John. Quote Link to comment Share on other sites More sharing options...
Martin Arnold 1 Posted April 18, 2020 Share Posted April 18, 2020 Hi J D 8. In a word no, probably a bit like you I could hear a hiss through the exhaust when the engine was turned over and naturally thought it was a leaking valve. Went through all the lapping procedures and nothing seemed to make any difference which was when I concluded that the gases were leaking between the insert and the head. In fairness it didn't seem to effect the running of the motors to any degree. As yet I haven't found a cure, had thought of running some cyno around the insert in head, but thought 1, it wouldn't last and 2, could ruin the head. Think it may just be the manufacturing quality is not up to the standard of OS or Saito. That said Saito abandoned the bronze insert idea some time ago, the valve seats are now cut directly in the alloy. It may well be something you have to live with in the Sanye made (SC/ASP/Magnum) engines, unless some bright spark can come up with a way of fixing them. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 18, 2020 Author Share Posted April 18, 2020 Martin, it sounds like you have the head distortion issue that we were discussing. You lap the valve, all is well, bolt the head down and it distorts which undoes all your lapping work as the seat is now bent. Engine Doctor has done a number of in depth posts about it. On the now not so poorly 40 i ran it again on a bigger prop to see how it went. I used my turnigy 13x5 wood prop as its a known prop to me and i have used them on WWI fighters before. Long story short, it loved it! With the heavier load the engine was more consistent and would hold top rpm for longer. Static compression is still pants, but when running its clearly fine as i recorded 8600rpm peak and 8400 flat for a good 15 second blast. This performance is excellent and only slightly down on my not ruined saito 45 when using the exact same prop and fuel. Idle could be brought as low as 2200 but i was aiming for about 2800 as the engine was very stable there and picked up well. At 2200 it would begin to cool down an got a bit lumpy. As much as i am tempted to keep fiddling with it the time has come to call it a day. I will repair the bearing extraction hole, replace the cam cover and that will do. The engine is running really nicely and given how fragile the castings are continued dismantling only risks stripping a thread. I might treat it to a prop driver, but we will see. The performance of the engine as is will be more than enough for a small WWI fighter and as this is what i have in mind for it i am more than happy to leave it alone. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted April 18, 2020 Share Posted April 18, 2020 Posted by Doc Marten on 17/04/2020 14:55:36: The Alum trick I mentioned. Another tool in the box. Removing ferrous metal from non ferrous castings. And another Edited By Doc Marten on 17/04/2020 14:57:45 That a really interesting tip that I had never hear of before Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 18, 2020 Author Share Posted April 18, 2020 its a new one on me. I do wonder how often you will come back to your cauldron to find your part has dissolved. Quote Link to comment Share on other sites More sharing options...
Jon H Posted April 20, 2020 Author Share Posted April 20, 2020 just a final photo of the finished engine with repaired crankcase. If you didnt know it had a hole through it and saw it at a glace you would never know. I still need to change the cam cover but that is not a major job. The broken throttle arm finally gave up so i modded an old laser one to fit. I think i have a dead OS20fp somewhere so i might be able to steal the throttle arm if i decide i want it back to factory spec. all i have to do now is finish the rebuild of my sc400 and asp160. Then its on to the next project Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted April 20, 2020 Share Posted April 20, 2020 Nice one Jon, overall the posts have been very interesting. Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted April 20, 2020 Share Posted April 20, 2020 Good thread Jon, looking forward to the next one. Quote Link to comment Share on other sites More sharing options...
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