Removing paint from engine
#26
It came up nice. Maybe a bit greyer than a stock clear one. Maybe I will do an LA .46 when I take it off the plane some day. It is quite black, but runs like gangbusters. Good thing rich guys like you do these experiments for us poor folks. OK, lazy old farts.
#29
I'll find out. I have an FP .10 - an underwhelming engine IMO. It runs okay, by doesn't idle low - I think 3,500 is about as low as it goes. As for the LA .25 I stripped - I am pretty much modifying everything except the cylinder head. It hasn't been shown to be fruitful to use a turbo or Nelson plug in these, so I'm not going to bother. I may adjust the squish angle in the stock head though.
#30
I think my FP and LA .10s were about even with a TD .09. Maybe a bit heavier, I checked with no muffler. It is quite heavy too. IIRC the AP .09 was a bit better than the TD, and the LA .10 had a very thick head spacer that I replaced with a thinner one. That helped things. Maybe the .25 would get some good results like that. We race them, but can't modify anything at all, so I have not tried much.
#32
10Q,
The bronze bush does serve both ends of the shaft. There may be a very slight relief along the length of the shaft port, but it looks similar to a 2BB layout. I wouldn't expect the full length of the shaft to be within a BB housing, would you?
(EDIT to add: BTW, was that marker comment on one of the pix the reason this engine was chosen for the treatment? )
Thanks for the stripper recommendation and your excellent photos!
The bronze bush does serve both ends of the shaft. There may be a very slight relief along the length of the shaft port, but it looks similar to a 2BB layout. I wouldn't expect the full length of the shaft to be within a BB housing, would you?
(EDIT to add: BTW, was that marker comment on one of the pix the reason this engine was chosen for the treatment? )
Thanks for the stripper recommendation and your excellent photos!
Last edited by Lou Crane; 03-19-2017 at 09:24 PM.
#34
Lou - I have a few other bronze bushed engines that had the bronze carried along the whole shaft. I would expect a "high quality" engine manufacturer such as OS to bush the whole crankshaft. No bother - I intend to basically beat the snot out of it and see if I can destroy it. I chose this engine because it's low time - barely run. It hasn't had a good enough chance to peel yet. When I'm done and the liner is peeled, I'll put a .25 FSR piston/liner into it.
My POS comment? It's a slug of an engine. But overall I feel the brand is an absolute ripoff. Nickel liners they called chrome, poor fitted Pistons, etc. I put a new piston and liner into an old 25FSR - loosest piston fit I've had in my hands. It runs, but not nearly as stellar as so many have made them out to be. The FSR is a pain in the butt to hand start - not good considering I'm gonna convert it to diesel.
Anyway, enough muddying of the subject.
My POS comment? It's a slug of an engine. But overall I feel the brand is an absolute ripoff. Nickel liners they called chrome, poor fitted Pistons, etc. I put a new piston and liner into an old 25FSR - loosest piston fit I've had in my hands. It runs, but not nearly as stellar as so many have made them out to be. The FSR is a pain in the butt to hand start - not good considering I'm gonna convert it to diesel.
Anyway, enough muddying of the subject.
Last edited by 1QwkSport2.5r; 03-20-2017 at 05:17 AM.
#36
I tried clorinated brake cleaner, non-clorinated, DOT3 brake fluid, acetone, and pure nitromethane. None of them did a reasonable job. Acetone was the best of what I tried, but I had to soak the head for 3-4 days and only then about 10% of the paint came off. The paint stripper worked great in about an hours time. (it took a few applications and subsequent scrubbing)
#37
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I was tipped off to a paint stripper that is metal-safe. Worked wonders on this LA25 I have. Klean Strip Premium stripper. http://www.kleanstrip.com/product/pr...ripper-aerosol
Follow all directions on can INCLUDING Wear chemical resistant clothes, gloves, safety glasses, and WORK OUTSIDE. The stuff stinks and is flammable as all get out. An old toothbrush works good for scrubbing the lifted paint off.
I found a surprise under the blue paint. . I also noticed the bronze crankshaft bushing doesn't run the entire length of the crankcase. Kind of a let-down.
Follow all directions on can INCLUDING Wear chemical resistant clothes, gloves, safety glasses, and WORK OUTSIDE. The stuff stinks and is flammable as all get out. An old toothbrush works good for scrubbing the lifted paint off.
I found a surprise under the blue paint. . I also noticed the bronze crankshaft bushing doesn't run the entire length of the crankcase. Kind of a let-down.
#38
I have a little Russian Stels .049 that had such a big clearance in the crank to housing, that it would not hold a setting. I drilled out the case, and spun out a bushing. Did not expect that. I pressed in a new one that I made up. It was very short. It is not needed to go all the way across, in fact the lip of the throat of the case should seal, and the opposite side can be relieved for less friction. It is a common mod. A bushing that goes all the way across is just extra weight. A lot of the guys here use the LA .25 for the 80 MPH control line combat. They are as light as a .21 and take a hit well, and run very steady with little maintenance. Crash them, hold nose down, open the needle to rinse out the dirt from the carb, and go again. We race them (no mods) in 100 mile races in less than two hours with pit stops, and they don't wear bad, or peel that I know of. Everyone says they sure are better than the old Fox .35 motors that we used to have. I never liked the Foxes, and shuddered when I had to buy one. I was pretty mad when I had to get an LA .25 too when the Fox was deleted too. They are a fairly good motor IMHO. Small carb for real performance, but a good beater. I am sort of sad that they are discontinued. At least the LA .15 is still for sale, hopefully for a long time. Nothing bad to say about them either.
#39
Cmon Tim , a bit of a let down . I bet u had a grin from ear to ear so it gives u another reason to bag them some more . I wouldnt worry too much about that bush . So what if that bush outlasts the rest of the engine ? Does that mean its still a prob. or good manufacturing practice . No use building a roof of a house to last a 100 yrs when the foundations will last 50 yrs ! I tell u what the la's I have seen are durable and then some . One in particular was crashed fairly often with a face full of dirt . No taking it apart and cleaning it , the owner just blew it off and away it went for a few more yrs . The internals were so caked with dirt that u could hear it grinding when it was turned over . Everyone at the club used to laugh at the abuse that thing took and still soldered on . I hope when u take the grinder to that thing and it blows up or runs like crud u wont come back here and say its a P.O.S. now that wouldnt be fair would it ????
Cheers pal.
Last edited by 1QwkSport2.5r; 03-22-2017 at 06:58 PM.
#42
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I tried clorinated brake cleaner, non-clorinated, DOT3 brake fluid, acetone, and pure nitromethane. None of them did a reasonable job. Acetone was the best of what I tried, but I had to soak the head for 3-4 days and only then about 10% of the paint came off. The paint stripper worked great in about an hours time. (it took a few applications and subsequent scrubbing)
Poor little LA .25 engine......(Smiles)
#46
All of the photos I've seen of the blue LAs showed a natural aluminum muffler. In fact, I've not seen a painted OS muffler yet. This is not to say they didn't come painted though.
I don't like the idea of painting an engine - one more thing to hinder heat dissipation. Anodizing doesn't affect heat exchange nearly as much. This is one of the main driving forces behind removing the paint from my LA .25.
I don't like the idea of painting an engine - one more thing to hinder heat dissipation. Anodizing doesn't affect heat exchange nearly as much. This is one of the main driving forces behind removing the paint from my LA .25.
#49
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O.S. Muffler E-2030 Blue 25LA
Here is Towers currently listed 25 muffler, discontinued of course. They don't show a blue muffler for the .10 and the engine I bought does not show the muffler.
Here is Towers currently listed 25 muffler, discontinued of course. They don't show a blue muffler for the .10 and the engine I bought does not show the muffler.
#50
O.S. Muffler E-2030 Blue 25LA
Here is Towers currently listed 25 muffler, discontinued of course. They don't show a blue muffler for the .10 and the engine I bought does not show the muffler.
Here is Towers currently listed 25 muffler, discontinued of course. They don't show a blue muffler for the .10 and the engine I bought does not show the muffler.
Huh.. I wonder why the blue engines didn't automatically get blue mufflers... weird. Anyway, I stand corrected Dave. Thanks.