Nick Brotherton Posted June 29, 2010 Share Posted June 29, 2010 Hi all, I have a rather old 4 stroke, its an OS FS80 and dates back to 1982 according to the OS website.The engine is almost new, having been sat unrun for a long time.The reason for this is probably that it lacks power, however I now know why - the head gasket is leaking rather badly. I assume d a gasket would be available butI have searched the web and cannot find any source of spares for this engine, in fact hardly any mention of this engine at all. I suspect it wasn't in production for too long. I was going to contact Just Engines but wondered if anyone out there could suggest anything? Shame to abandon it as it looks brand new. RegardsNick Quote Link to comment Share on other sites More sharing options...
David perry 1 Posted June 29, 2010 Share Posted June 29, 2010 Cant you buy gasket materil from halfords and make one? Often a paper one does, but maybe not here. I dont know. Email the wizard of oz! (i.e. Brian Winch) D Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted June 29, 2010 Share Posted June 29, 2010 Google John D Haytree ... Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted June 29, 2010 Share Posted June 29, 2010 What sort of a gasket is it? A paper one or a metal shim? If paper then make one as suggested....gasket paper available from Halfords or your local motor factors...if its a copper shim then re-anneal it.....if you have the dimensions then Just Engines may well be able to fine one to suit......ASP do an 80 fourstroke which might fit...see here Quote Link to comment Share on other sites More sharing options...
Nick Brotherton Posted June 29, 2010 Author Share Posted June 29, 2010 Thanks for the replies chaps, appreciate it. Its a metal gasket, but doesnt look like copper, but steel or aluminium? I will try Just Engines but they are on holiday this week. Thanks for the tip about the ASP, perhaps it will fit, JE do both OS and ASP so will speak to them next week. John Haytree doesnt seem to have a website but I now have their phone number. regards Nick Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted June 29, 2010 Share Posted June 29, 2010 John is semi retired & is a pre-internet kind of a chap!!! A great guy though....been supplying model engine spares since Adam was a lad!!! You have to use the old fashioned method of ringing up & speaking to him!!!!!! Its unusual for the metal gaskets to go however....might it just be that the head wasn't tightened down properly...what makes you think it was actually leaking? 4 strokes often have very low compression when turned by hand...especially if the throttle is closed... Hope you get it fixed though....... Quote Link to comment Share on other sites More sharing options...
Nick Brotherton Posted June 29, 2010 Author Share Posted June 29, 2010 Thanks Steve, I put some liquid soap around the joint and it bubbled like crazy when run!The engine hasnt run well since i put it in a model and will only run at any sort of decent rate with the needle just one turn out. Thats obviously too lean and consequently once the engine gets warmed up it starts to overheat, struggles a bit and stops unless I throttle back (which I do every time it does it). I'm sure the head was tight enough. I just had a call from a club mate who reckons he's got a gasket (or shim) that will fit. I will try that tomorrow and failing that will give John H a call. Thanks again. Nick Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted July 2, 2010 Share Posted July 2, 2010 That sounds like a leak then!!! I hope the head isn't warped...... You could maybe try a smear of silicone instant gasket before bolting the head down...... Good Luck... Quote Link to comment Share on other sites More sharing options...
Stuart C Posted July 2, 2010 Share Posted July 2, 2010 In the late 60's, we used to throw away the gaskets and lap the head to the liner using Vim. It only takes a couple of minutes, and never leaks. Ps, be sure to wash off all the Vim before reassembly. Quote Link to comment Share on other sites More sharing options...
Nick Brotherton Posted July 2, 2010 Author Share Posted July 2, 2010 Thanks for all the replies, very good of you all to take the time.Its now fixed. The head wasnt leaking - it was the inlet manifold . I also had 2 tiny pinholes in the clunk tubing. Typical Will put it back in the plane tomorrow and hopefully fly it without any problems! regardsNick Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted July 2, 2010 Share Posted July 2, 2010 Looking at an alternative possibility, could it be simply overheating as you seem to suggest this problem has started when installed in the model? The head will get extremely hot around the exhaust port and could it just be be boiling the soapy water - or alternatively the exhaust not sealing? Have you done the leak test with a cold engine and cranking it on a starter without a glow? The behaviour you describe is typical of overheating which is usually a cooling airflow problem - the mixture shouldn't change with warming up to any great degree from the initial setting due to normal running... Edit: That'll learn me to take so long composing a reply! I didn't see your last posting Nick! Edited By Martin Harris on 02/07/2010 22:51:35 Quote Link to comment Share on other sites More sharing options...
Former Member Posted July 11, 2010 Share Posted July 11, 2010 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted July 11, 2010 Share Posted July 11, 2010 Eric Can you still get Vim / Ajax /caustic soda ?And proper bleach for that matter? We're in the wrong century I thinkBut they might be available in a "bubble pack " Edited By Myron Beaumont on 11/07/2010 19:15:15Edited By Myron Beaumont on 11/07/2010 19:17:05 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.