Seized OS 55

[Gate88]

sigh, i give in with you.

cheers

You should certainly give up on advising people about engines.

[Delarado]

Does it allow air in too making it run leaner?

[anjki]

No prob here Guy.I tend not to shout to much,ask any of my freinds.

Your temperature differnce is because your bearings have upset the mixture.

andy k

[anjki]

does it allow air in too making it run leaner?

bingo!

[Planehazza]

Thanks for all the comments guys. There are many sources out there suggesting to run (only) the first 1/2 - 1 tank idling, just to get the engine worn in. Then, break in begins with gentle sports flying, and then tuning begins. There is NO WAY ON EARTH I have killed this brand new engine by letting it idle on recommended OS settings. And if I have, well it's a fault with their instructions.

[pgkevet]

How in gods name do the bearings adjust the mixture???

As it happens I agree with most of what you said..but crapped out bearings will affect mixture flow through the crankcase..they're lubed by it normally.. and anything affecting crank pressures will work backwards on a two stroke to the piston chamber and also the exhaust tank pressure.

I also idle new engines on the ground - but unless it's really mucky rich and spitting fuel from the exhaust then not for long at a time. 1/3 tank is less meaningful here than time; a mucky rich third being 2-3 minutes and a lean one way way longer.

The trouble is there are lots of variables..why the new engine? Was the previous one toasted and the owner didn't flush the muffler and sucked debris back into the new one? Is there a problem with fuel lines etc?

If it's siezed but looks OK then that doesn't make immediate sense. Broken ring? Can't view the liner for scoring? Problem on the piston skirt? It needs disassembly and then a polite chat (to start) with the retailer

[ChrisB]

Does OS not advise you to fly it rich to bed in the engine?

Never heard of idling an engine for breaking in but hope you get some satisfaction.

[Made2Fade]

Looking forward to seeing some pics Harry as this will tell the story mate

[anjki]

Does OS not advise you to fly it rich to bed in the engine?

Never heard of idling an engine for breaking in but hope you get some satisfaction.

not sure what they advise,but running an engine too rich will hinder the running in process.


cheers
andy k

[Delarado]

Yeah it'll act like lubrication... Better excess lubrication than excess heat though IMO.

When I ran in the only nitro engine I ever owned I think I started it then Richened it up till fuel started splattering from the exhaust and then just let it idle there, with a little throttle every now and then just to clear it out when it loaded up with fuel and tried to stall.

I then leaned it gradually every 1/3 of a tank until it seemed about right visually and then started to move it keeping an eye on smoke levels and engine response. I kept it so it had a little bogging for the first 5 or so tanks and drove it lightly (it was an rc car) and then started to lean out for best response.

[Gate88]

Oh look!

Here's a video of someone running in their OS55 on the ground.

And guess what?

It doesnt sieze up once!

Must be a bit scary for some of you to watch eh? Bit like when you found out the earth wasnt flat?

[Andy from Sandy]

Whilst I realise that running the engine on the deck like in the video will not cause it to seize up it is a complete waste of fuel.

[electricsceadu]

not only is it a waste of fuel it will glaze the liner up and the ring will never bed-in
the only way to bed the engine in is to fly it varying the load on the engine during the flight
sat in a hover is no good
flying at 1/2 throttle is no good



on the seized 55 was the carb clamp tightend before it was used ?
as os ship them with the carb not fully seated and the clamp only nipped up and not tight
was the head bolts checked? its known for them to be loose on a new engine
was the carb clean? any swarf in the carb?
is the fuel tank pressure nipple hole blocked?

[astra 8vt]

an engine should not sieze up on idle just sitting there not in that short time
but theres no way your going to bed it in just leaving it like that and engine should be started idle sorted the run as varyed loads but nothing over the top to start with just to bed everthing in for a few tanks atleast

sorry i would give them hell over this

i remember when i worked in a model shop repairing /building cars and every car was run in on idle for atleast 2 tanks the varyed runs but never full throttle for atleast 5 tanks they had no cooling fans on them

[Gate88]

an engine should not sieze up on idle just sitting there not in that short time
but theres no way your going to bed it in just leaving it like that and engine should be started idle sorted the run as varyed loads but nothing over the top to start with just to bed everthing in for a few tanks atleast

sorry i would give them hell over this

i remember when i worked in a model shop repairing /building cars and every car was run in on idle for atleast 2 tanks the varyed runs but never full throttle for atleast 5 tanks they had no cooling fans on them

Woah!

Careful mate, much more blasphemous talk like this and you'll end up on Raptorheli2's ignore list!!!