Hogster Posted January 8, 2011 Share Posted January 8, 2011 I have a Irvine 46 in a solo star trainer. Its a second hand engine that I think was stored unused for some time. Anyway, last week one of the guys at the patch last week said the engine sounded a bit rough. I`ve just started it up again and there seems to be a rough sort of rumbling noise. Its difficult to tell whether its normal to an inexperienced ear. I have turned the engine over by hand and it feels smooth. There is a little play side to side. Do you think the bearing are on their way out? Is there an easy test without having to strip the engine? Quote Link to comment Share on other sites More sharing options...
Gavin Livsey Posted January 8, 2011 Share Posted January 8, 2011 Hogster Sounds like what happened to mine. Replacing bearings is easy enough. There's a two part film on you tube showing you how it's done. Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted January 8, 2011 Share Posted January 8, 2011 hello hogster......take out the plug and slowly turn the engine over......sometimes you can hear/feel the rough spot's on the bearings.....as said......easy replaced..... ken anderson ...ne...1. Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 8, 2011 Author Share Posted January 8, 2011 Thanks guys. Ken, just tried that and your right. Sounds very rough. New bearings it is then. Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted January 8, 2011 Share Posted January 8, 2011 ...and another check is to try rocking the prop - if there's any noticeable play the bearings are shot. Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 8, 2011 Author Share Posted January 8, 2011 Hi Martin, Yes there is some play. I also noticed a small metal shard on the carb barrel. I hope I havent left it to late Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 9, 2011 Author Share Posted January 9, 2011 I think this picture of my rear bearing confirms the problem me thinks . The piston is quite clean so it suggests although the engine has had little use it hasn`t been stored to well. Don`t you think? Quote Link to comment Share on other sites More sharing options...
Klippy Posted January 9, 2011 Share Posted January 9, 2011 Looks to me as though the engine wasn't cleaned of methanol before storage, methanol is very hygroscopic and you ended up with water/methanol/oil mix in the bearings. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted January 11, 2011 Share Posted January 11, 2011 Yup that is one cream crackered bearing......!!!! Looks a bit rusty too as Tony says....from now on use some "after run" oil at the end of each flying sesh....just ordinary 2 stroke oil will do..no need to buy the expensive "real" stuff. Have you sourced the new bearings OK.....your local bearing factors will usually sort you out; much cheaper than Irvine spares. Plenty of on line suppliers too.....Google is your friend here..... Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 11, 2011 Author Share Posted January 11, 2011 Hi Steve, I have been using 3in1 oil as after run oil. But I will be using 2stroke oil in future. This engine came to me 2nd hand after along time in storage and I think thats where the damage has been done. I cant complain it was a very cheap deal. I ordered replacement bearings from Just Engines Sunday night and they arrived this morning . I could probably get cheaper from elsewhere but as its my first foray into model engine repairs I wanted to make sure I had the original parts so if it doesn`t fit or they break I know who to blame Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted January 11, 2011 Share Posted January 11, 2011 Thats fair enough Hogster...Just Engines will see you right I'm sure....I suffer from deep pockets & short arms so I always look for the cheaper option!!! 3 in 1 is better than nothing but isn't known for its lubricating properties in engines!!! 2 stroke oil is designed for engines & burns very cleanly (no ash) so is ideal for our purposes. Best thing is to run the engine completely dry (of fuel) so its nice & hot to evaporate any water then add a carb full of after run oil & spin it over on the starter. Job done!!! Like all engines they are best used often....storing them doesn't really do them any good so tell your wife that you simply MUST go flying every week to save money on engine repairs........!! Didn't work?? Nope didn't work with my wife either!!!! Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 12, 2011 Author Share Posted January 12, 2011 Mmmm bit of a problem. The new rear bearing is bigger than the one I took out. It seems that on an irvine 46 mk3 there are two possible sizes. Anyone else aware of this? Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted January 12, 2011 Share Posted January 12, 2011 Strange....I would have thought JE would be aware of this & ask the question.....I'm sure they will swap it for you!!! Or revert to Plan B & visit yer local bearing factors & ask them to match it....... I do recall that the original Irvine 40 (from the late 80's) had a custom made rear bearing (as in custom made for Irvine) & was a slightly smaller od than the "standard" size bearing. When Irvine stopped making the engine supplies of spare bearings ran outr pretty quickly too. The solution was to Loctite a circular shim around the outside of a smaller bearing to make it the correct od to fit the housing.......didn't work very well though!!! Why Irvine insisted on a custom sized bearing is anyone guess!!! Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 12, 2011 Author Share Posted January 12, 2011 JE say that the one I should have ordered is for the Mk4 (silver carb) but my engine is deffo Mk3 with black carb. Unless its been swapped over; are the carbs interchangeable? Quote Link to comment Share on other sites More sharing options...
Klippy Posted January 12, 2011 Share Posted January 12, 2011 Sadly, it's become standard operating procedure for Manufacturers to fit non standard (read slightly altered) bearings in order to make more money out of spares. When I was in the engineering industry it was the norm for us to get 60% discount on all bearing orders! There's a huge markup!Hogster, if the OD is too big why don't you get an engineering grinders to skim it down for you. Get them to measure the bearing bore in the engine first, they will be able to recommend the correct final size. When you get the bearing back, wash it well in Meths, then Laquer thinners, then petrol, then meths again. Then lubricate with after run oil before fitting. This is to be absolutely sure you get all the grinding nasties out before you fit it. Being in Africa where all machinery is imported we used to go that route often, you can't wait for the parts to arrive! Every hour the machine stands is money! Quote Link to comment Share on other sites More sharing options...
Hogster Posted January 12, 2011 Author Share Posted January 12, 2011 Tony, the I/D is to big also. But its OK Just Engines are looking after me. They have the one I need and are happy to swap. Its just strange that I seem to have a hybrid engine. part Mk3 and part Mk4. Perhaps it should be Mk3.5 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted January 12, 2011 Share Posted January 12, 2011 Posted by Tony Prince on 12/01/2011 10:42:51:Hogster, if the OD is too big why don't you get an engineering grinders to skim it down for you. Get them to measure the bearing bore in the engine first, they will be able to recommend the correct final size. When you get the bearing back, wash it well in Meths, then Laquer thinners, then petrol, then meths again. Then lubricate with after run oil before fitting. This is to be absolutely sure you get all the grinding nasties out before you fit it. Are you serious Tony? Quite apart from the cost of getting the bearing ground, I'd have thought this would be an absolute last resort as the chances of contamination must be horrendous! Perhaps you were in a "needs must" situation but I really wouldn't recommend this solution to the average modeller with the alternative of returning a bearing to get the correct one! Edited By Martin Harris on 12/01/2011 11:36:21 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted January 12, 2011 Share Posted January 12, 2011 Posted by Steve Hargreaves on 12/01/2011 08:53:27: I do recall that the original Irvine 40 (from the late 80's) had a custom made rear bearing (as in custom made for Irvine) & was a slightly smaller od than the "standard" size bearing. When Irvine stopped making the engine supplies of spare bearings ran outr pretty quickly too. The solution was to Loctite a circular shim around the outside of a smaller bearing to make it the correct od to fit the housing.......didn't work very well though!!! Why Irvine insisted on a custom sized bearing is anyone guess!!! When I spoke to Irvines about spares for my ancient Irvine 40 (bought around 1976 so they pre-date your estimate a bit!) just after returning to the hobby after a 25 year break they explained that the bearing used had been dropped by the bearing manufacturers and was a mixed imperial/metric one so I'd imagine that when they specified it all those years before it was a standard item. In addition, I'd have thought that the cost of getting custom made bearings for the relatively small volumes would have been prohibitive? P.S. IIRC the "official" solution was to specify a bearing with an oversized bore and sleeve the crankshaft.which, on thinking about it, would allow a correct width bearing to be obtained.Edited By Martin Harris on 12/01/2011 12:05:59 Quote Link to comment Share on other sites More sharing options...
Klippy Posted January 12, 2011 Share Posted January 12, 2011 Yes Martin. when needs must the Devil drives! In Third world countries you often don't have any options. We would send them the bearings clean, and then clean them again when they came back. Anyway Hogster is fixed up so he won't have to resort to 'dirty tricks' Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted January 13, 2011 Share Posted January 13, 2011 Martin I think that may have been the situation with my engine.....it was an Irvine 40 dating from the late 80's bought for a Morley Hughes 300 helicopter in the days when we used aero engines in helis & ABC was something new!!!! Quote Link to comment Share on other sites More sharing options...
JOHN THOMPSON 5 Posted January 13, 2011 Share Posted January 13, 2011 Hi all, just picked up on this thread , I,ve been in engineering since I left school , too long ago to remember, we always use a company called BEARING SERVICES, they never fail to get the right size bearings, simply meaesure the ID ,OD and FACE WIDTH , and they go off and bring you the bearing you need evn cross over sizes metric to english, they have a web site and are very obliging, they also offer a hand full of different qualities of bearing and prices at whatever size your after,well worth a look . Quote Link to comment Share on other sites More sharing options...
Erfolg Posted January 13, 2011 Share Posted January 13, 2011 Do bearing services still trade? In this day and age, perhaps the Internet may be a good source for other bearing procurement process (do you not love fancy words?). Quote Link to comment Share on other sites More sharing options...
Jimbo565 Posted January 13, 2011 Share Posted January 13, 2011 Erfoig, Bearing Services are still going strong in my neck of the woods,just like John I used to deal with them when i was working and they always provided a good service.I still use them for my engine bearings. Jim Quote Link to comment Share on other sites More sharing options...
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