Got Followed Home Today....

Looks to honestly be in good shape overall. It had been run for sure, but in my opinion not stored well with the castor stuck carb, and teh green residue. But I do agree that it probably has low run time. As for model planned for it, no. I am very honestly considering another airboat for this one. I will attach one of my FSR 40 on my big airboat. Maybe a Mini-Me.....

Just another update. After posting this on another site, I was told to check for peeling liner. So, I remove the exhaust, and wow! This thing is DIRTY inside. Crud build-up everywhere. So, I did remove the head, backplate so I can give it a good antifreeze bath and be able to blow it out. I do not know how to remove the piston and cylinder liner, so I will clean it as is and see how it looks after. This is just so I do not ruin something by trying. Anyways, I will be doing this hopefully tomorrow, but with a busy week, I may not get to it till after the long weekend. I will post updates as I go along. However, I will clean the carburetor seperately in a bath of fuel so I do not have to dismantle teh thing as it is set to run as it sits.

You want the plans for this one? I have them saved before my computer crashed. Just may have to bear with me for a day. All 1/8" ply, some parts doubled, but strong!

Plus I gots me a smaller one too. ......

https://servimg.com/view/17063256/91

Nice looking engine man !! After you boil it the liner may come out on its on , The carb. settings can be saved for future reference , but i feel sure you will have to take the needle out to get the spray bar cleaned .

Here is just a little update as of current. The engine minus the carb are now in the slow cooker.... Will keep this updated as I go along. Also to mention, carburetor was bathed in a glass of nitro fuel overnight and cleaned the other evening.

Ok. So I boiled this thing and as it was going along, I was able to remove the piston and liner from the engine. Soaked it again for a bit and cleaned everything off, blew it out and wiped it off. I brought it back inside and added a drop of oil here and there as I assembled it. I made a new backplate gasket with heavy paper made for wrapping parcels to ship. For tightening things as I did not have the propper hex keys here with me, I used the appropriate size Torx screwdriver. I went around clockwise to snug everything up. After that was done, I went around in small increments and tightened it all in a criss cross fashion. Now I cannot believe the compression this thing has now. It is almost scary! Hopefully I will have a chance to run it tomorrow, but realistically it will be next week. But at least it is all back together now. Just thought I would share this update with you all for now. More to come.....

NEW222 wrote:Ok. So I had something follow me home today. Found it locally online and when I saw the picture and price, well.... It needed a new home. I am very happy with my 40 FSR, so thought it needed a little brother. Anyways, this is it just how I picked it up. It now needs a good cleaning as it has a bit of green stuff all over the carburetor and areas.

The .25 FSR OS is a very powerful engine, I hope you enjoy it a lot.
It just has appeared here in a sale of my country a new one in its box ... I look at it with affection! Haha .... but I'm still thinking about smaller models and the Cox! ... although it's tempting !!

That's a nice engine man, I have the 28 and 25FSR both are quite powerful. The peeling Liner warning is for the ABN version which does have a habit of peeling. Yours looks to be the ABN version since it has the newer carb. The older version was lapped iron and runs equally well. You will love how it runs, it is easy to start and once adjusted, it will idle all day and has a nearly silky smooth response to the throttle. have fun with it
(Bandit)

My early Norvel experience had me think a LOT about the OS liner "peel" I read about later when I was researching getting various used OS engines

A lot of the liner peel stories seemed to come from a lot of what I consider incompetent/ignorant users...not so much I found wrong in the threads about the engine--- but I was starting to see the same screen name, in other threads ask a lot of --to me-- dumb questions

Eventually, I bought a fair amount of OS FP/LA/FX engines and got some that were the supposedly the bad liner suspect ones ....so far zero problems

I am not at all disputing that Liner peel is not real...it is... I have some (they were used when I got them) fortunately Tower (at the time) still carried the replacement parts

Here are my thoughts... there are many new engines designed to have a LOT of top of the bore Piston to liner PINCH....actually part of the deliberate design.... at normal operating temps the clearance is JUST right...BUT COLD there is a LOT of pinch

Back to the Norvel experience... Many of us found them impossible to start and run in...Due to this NV changed the instructions to include some nonsense about removing the glow plug... oiling...and fast hand flipping or electric starter / drill motor run to wear in the tight pinch....NONSENSE! and a lot of us engine smart guys knew it!..... heat gun the head and it will start and run in perfectly

Never ever slowly prop over a NEW engine...no mater what type...good rule! Heed it!

Never ever Turn a new engine to Top dead Center and NOT do a complete flip through...I am very serious!

The pinch is so tight COLD ---that ALL the lube will be squished or scraped away and nothing left but pure metal to metal contact --under pressure... the basic definition of a seized set of parts... any new movement WILL wear away some metals....fact!

In My stash
New Magnum 25s
New OS LA 25s
New ASP 21
Many new Norvel .049/.061s
New Magnum .52
New OS LA 40s and 46s

every one of them has a very very tight top of stroke pinch to the point of being squeaky on slow prop over....

MY real point is... I often wonder, when reading about OS line peel ....how many were ruined by an ignorant owner before any fuel was introduce to run the new engine....

TDbandit wrote:That's a nice engine man, I have the 28 and 25FSR both are quite powerful. The peeling Liner warning is for the ABN version which does have a habit of peeling. Yours looks to be the ABN version since it has the newer carb. The older version was lapped iron and runs equally well. You will love how it runs, it is easy to start and once adjusted, it will idle all day and has a nearly silky smooth response to the throttle. have fun with it
(Bandit)

Thanks for teh good news of this thing running. This year, overall, was a terrible year for me. I did not honestly get out once up in the air. As well, I had not even bench run engines as was in the years past, so I did not get a chance to run this one yet. But as of earlier today, we winterized the cottage, so I may still have some time to run the engine as I will now be spending all my spare time at home. Oops. Forgot to mention that upland game bird season is on now! Well, I will be seeing what spare time I have left for it. If it does get run, I will be letting you know how it did run.

A lot of it has to do with what you mentioned, the "pinch" at the top of the sleeve was not too tight in the early OS ABN engines in my experience. I had an OS 61SF do it to me but it was due to over heating to a point of flame out. it's usually caused "IMO" by Poor fuel quality, improper break-in and over heating and the peeling usually started at the ports. The real pinchers are the true ABC engines, I have experience with the high end competition Nova Rossi made RC car engines RB, REX, Collari ect (Used to race 1/8 scale nitro buggy) and they were so tight that you had to pre lube them and use a heat gun or heat cuff to pre heat the engine up to 200 deg and immediately plop it down on the starter box, start it and set it slightly lean and run it at a high idle for a full tank of fuel before you could start the real breakin failure to do the "spit n polish" would usually result in a destroyed engine costing 400 dollars or more. So yeah a lot has to do with peeps that don't know what they are doing lol (Bandit)

Wow that's really cool! I have never seen an rc airboat before.

When i was ripping around with rc cars the hpi .25 was notorious for shearing the crank pin off after about 2 gallons. But to rebuild you would need to remove the liner, i have had success with heating the crankcase up with a heat gun until a drop of water will boil off, then pressing the liner out with a piece of wood. To reinstall, freeze the liner and heat the crankcase. Once the crank case is at temp drop in the frozen liner. You can speed the freezing process by inverting a can of compressed air (used to blow dust of keyboard etc..) and spraying the liner (I think its liquid C02) liquid should hit the steel and cool it rapidly, but a couple hrs in the freezer also works just fine too.

Super tight fit at the top of rc car engines (very tight machining tolerances probably part of the reason why they can survive on 11% oil). The manual always said to break them in by using a hairdryer to pre-heat them (get to operating temperature), which made a lot of sense to me and worked really well. I have read the Norvel oil and flip method in their manual and thought that was super odd way to do it.