New engine run in tips?

[jaso]

Just after some tips on running in my new CMB .90

I was told by some one to maybe start off with a slightly smaller prop than ideal until I've put some run time into it,but I would have thought that running a smaller prop maybe not good for the possible accidental over rev.

I'm a mechanic by trade and I've always thought that slightly loading a engine was more beneficial to run in than an unloaded engine. Any tips anyone?

And I know that the most critical thing is to ensure that it is running a bit too rich as a lean run would not be good in its new condition as at any time of a engines life.

 

[Don Templeton]

Don't under prop a nitro and don't over prop an electric.

However, slightly smaller or less pitch shouldn't be a problem for breaking in.

 

[MikeP]

I think the idea is that a slightly under sized prop will get you running so you can get in some beak in time without other problems.

-MikeP

 

[nitrotoys]

Well that .90 is a torquey engine. It can handle big props. As far as a break in, I would run it rich a couple of tanks, and then set in the needle.

and go from there.

Best thing for props, as we cant check RPMs on nitro engines. I just get a couple different props and check speed, and pitch up and play untill i get my max speed.

NT

 

[Ron Olson]

There are probably as many theories as there are members in here. One friend runs them rich like we alll should, one thing that he does differently is to run it fast on the straightaway then slow it down it the corners to "cycle" it. I've found that with my engines that they will swing a bigger blade once they're broken in. Some take longer than others. Pre-lubing an engine before starting it the first time is highly recommended just like on full-sized engines. That is why it is discouraged to pull-start engines in the Hobby Shops or before it is ready to be fired for the first time.

Use the fuel that you plan on running in the engine, there is a lot of controvery on this subject alone.

 

[nitrotoys]

See the first tank i do heat cycle the engine, run a bit, and then set the piston at BDC untill cool and repeat.

then the first 2 tanks i run it no more than half throttle, course towards the end of the second tank. IM ON IT.

but then 3 tank lean it out some more and run it.

Most of the good engines, NEED to be run rich, My Mac and CMB Like to run rich. So i leave it a little rich.

My CMB Took alittle over a gal to break in.

my mac, about 1/4-1/2 gal to break in.

My Zen, well just broken. ;D ;D ;D

Never hydro lock a engine, I like to take out the glow plug and spin it with a rag on top to see how much fuel i am getting and that will normall get fuel flowing, and start right up.

if it dont start in 5 seconds somethings wrong.

Now if your engine LOCKS are you trying to start it, (to much fuel) In there, take plug out and spin with a rag on top. and lean it some and start over.

I use A3 plugs in my CMB and seems to do well.

I didnt like the MC-59s, hell the MC-9s for that matter tooo.

NT

 

[Ian Inverarity]

Each to their own! ;D

My method: Well of course you want to run the engine rich so that there is plenty of oil, but also I have been told that it should be up to temperature as well, which it generally wont do running rich.

I run my boats in on the stand at home (when the neighbours are out). At idle. I have water in a bucket syphoning into the exhaust cooling only. I run it very rich and dont rev it. I hook it to a bottle and use 2 or 3 litres of fuel. the engine gets up to temp, but is running low stress and rich.

I use ear-plugs tho! :

Ian.

 

[Ozzy]

Hay Ian,

You must love the smell of nitro in the morning.

 

[Ian Inverarity]

Ozzy,

Took months for the lawn to grow back in that spot!

Smelt nice tho!

Ian.

 

[Propjockey]

What about ringed engines?

 

[jaso]

I think I remember reading somewhere that the CMB engines come from the factory, with the needle set at a rich run in setting so you can simply fuel it up, check for the normal prestart settings and fire it up . I've been in the boats enough to know rich and lean with no troubles so if I started it at this I'd soon know if this is true as soon as it fires up. Also if these engine have lots of torque, could I put a std say ABC h50 on it and go, or is that just a matter of boat and set up etc? Does any one purposely over prop there glow engines to run in or is this likely to cause excessive heat which may be bad for run in period?

 

[ScottVanSlooten]

Run it as rich as you can (on a stand) and cycle it though heat range by leaning to get it hot and richining it to cool it for 2-3 tanks and the n head to pond and start out rich and run and lean it little at a time to bring it on needle. This work for us Scott

 

[Ian Inverarity]

Jaso,

I would start off with a smaller prop first, when the engine is new and tight and you are running it rich it wont make a lot of power, so that it can run you might like to start with something smaller like a stock 1667. If I am running an engine in on the water I prefer to keep it's load down.

Ian.

 

[jaso]

Ian,

I've just bought a 1667,h50,and a h45.

So if I start out with the 1667, keep it rich it should be ok. How much fuel would you put through it before starting to lean it out and play with other props?

I was thinking at least say 3 tanks full till dry. ?

 

[nitrotoys]

Dont run your tank DRY.......

As your tank runs down, it leans the engine out as it lowers in the tank. So there is ONE Reason you start RICH On the beech. And remember less fuel, less oil.

if your just playing, its not going to hurt it if its a tad bit rich. course i always run my a tad rich.

If i remember right, the CMB I dont think will keep flame if its tooo lean. I Know my MAC is that way.

I also went the bigger fuel lines on all my boats.

they LOVE THERE FUEL.

THAT CMB IS A THIRST MOTOR. KEEP NITRO ON HAND.

NT