By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by CML

New gas engine break in

Different methods

All Topics | Latest Posts

Search for:  in Thread Title in  
bhups matharu04/05/2020 19:09:56
avatar
13 forum posts

Hi Guys... got a new dle55ra in A Yak 54, just wandering how you break in new engines,I.e on the ground on the plane or on a test bench or in the air? Regards Matt

flight104/05/2020 19:27:59
avatar
747 forum posts
37 photos

give it a first short run with oil content as instructions on the ground in plane to make sure it works then then go fly making sure you baffling is good and it dosent overheat, just don't ring it out keeping max throttle to short bursts, when its run a bit 1 to 2L then tweak with the hi/low settings. if you run it in on a bench you will have to run it in again in plane as operating temps and prop sizes are different

Gary Manuel04/05/2020 21:45:22
avatar
2307 forum posts
1559 photos

Gas?

Do you mean petrol?

One is a liquid and the other is ... erm an Americanism.

bhups matharu04/05/2020 22:18:50
avatar
13 forum posts

Gary.. yes petrol )... been on too many American forums 🤣🤣

flight104/05/2020 23:46:37
avatar
747 forum posts
37 photos
Posted by Gary Manuel on 04/05/2020 21:45:22:

Gas?

Do you mean petrol?

One is a liquid and the other is ... erm an Americanism.

EEr ,,,, it is gas when it goes bang in the cylinder/s and before that it was gasoline, it's a liquid obtained by the fractional distillation of petroleum no gas no bangsurpriseangel

Gary Manuel05/05/2020 02:13:55
avatar
2307 forum posts
1559 photos

"Gasoline" is actually derived from "Cazeline", a U.S. trade name of the liquid refined petroleum, referred to as "Petrol" in this country. Calling it Gasoline is rather like calling all vacuum cleaners a "Hoover" - another U.S. trade name that's stuck.

 

P.S. No disrespect intended to bhups or flight1. Just having a bit of fun at the expense of our American cousin's (mis)use of the ENGLISH language.

Edited By Gary Manuel on 05/05/2020 02:20:10

flight105/05/2020 09:24:00
avatar
747 forum posts
37 photos

language is an involving thing, one can't be offended by it can one and it's still a gas that explodes when ignitedwink

Gary Manuel05/05/2020 12:28:19
avatar
2307 forum posts
1559 photos

Gas also explodes in a glow engine, a diesel engine, a jet engine and in a proper (CO2) gas engine but you don't call them all gas engines. How would you distinguish these types from one of your "gas" (petrol) engines? devil

Gary Manuel05/05/2020 12:35:12
avatar
2307 forum posts
1559 photos

bhups - I forgot to answer your question - Sorry.

Generally as flight1 says. Use mineral oil to start with and plenty of it and maybe slightly rich. Once it's running reliably on the ground, get it up in the air. Don't worry if it pops and burbles a bit due to running rich. After a couple of flights, start leaning it out a bit. After a gallon or two, switch to a good quality fully synthetic racing oil.

edit - bin the supplied DLE spark plug in favour of NGK CM6. Change plug once fully run in.

Edited By Gary Manuel on 05/05/2020 12:39:57

bhups matharu05/05/2020 12:40:05
avatar
13 forum posts

Thank you guys! I was quite enjoying that🤣🤣

Former Member05/05/2020 15:24:27
161 forum posts

[This posting has been removed]

Stephen Smith 1405/05/2020 21:49:39
237 forum posts
Posted by Jason Channing on 05/05/2020 15:24:27:

Never yet had an engine where the fuel explodes ?????????????,

Or me, in mine there all a controlled burn.

Gary Manuel06/05/2020 00:26:10
avatar
2307 forum posts
1559 photos

In my opinion, flight1 is quite correct that all I/C engines use a series of controlled explosions to move the pistons down (and up).

Choice of oil to use for running in will always be subjective (like a lot of things are). I think mineral oil helps to speed up the running in process.

extra slim06/05/2020 09:01:32
503 forum posts
49 photos

I do the same as Gary as break in is a lot quicker, has worked for me perfectly, but each and to their own.. no right or wrong I guess

Former Member06/05/2020 09:13:07
161 forum posts

[This posting has been removed]

Cuban806/05/2020 09:43:53
3051 forum posts
1 photos
Posted by flight1 on 05/05/2020 09:24:00:

language is an involving thing, one can't be offended by it can one and it's still a gas that explodes when ignitedwink

Yes Jason, I always thought that it was petrol vapour that was being ignited......and that it burns and expands rather than explodes (detonation)....................dont know

Interesting stuff - saw a programme a while back that compared high explosives and low explosives.

Edited By Cuban8 on 06/05/2020 09:49:30

Gary Manuel06/05/2020 13:35:32
avatar
2307 forum posts
1559 photos

Yep - changed my opinion. Petrol combusts rather than explodes. Even less reason to call petrol gas then wink

Regarding the use of mineral oil during run in - it's subjective as I said, but HERE's Shell's explanation of why mineral oil should be used (in full size aircraft engines). Read up - there's plenty of (conflicting) info out there. I would never go so far as to say ignore a person that thinks this or says that. Make your own mind up.

One thing that's not been made clear, regardless of which type of oil you go for. After the engine has warmed up, it's important to give it several 10 second or so blasts at raised power levels then let it slow / cool down for a few seconds between blasts. I generally do 3 or 4 blasts at half throttle, 3 or 4 blasts at 3/4 throttle, then half a dozen blasts at full throttle. This helps to seat and harden the piston rings / liner throughout it's full movement range (and is the main reason for using mineral oil). Once this is done, try to get a decent tickover and go flying. I'll probably be criticised for suggesting this way, but it's what I've found to work after much reading up. Worst thing you can do in my opinion, is to treat it with kid gloves and not give it full throttle. All my petrol engines have been run in this way and I've never had engine trouble.

bhups matharu06/05/2020 14:07:24
avatar
13 forum posts

Gary, sounds good! While we're on the subject of gas/petrol, any of you guys use copper or aluminium for your fuel tank tubing?

john stones 106/05/2020 14:18:02
avatar
11688 forum posts
1517 photos

No expert on oil myself, not read any insights off whoever, if Stihl market mineral oil, and recommend for their tools, I'm happy to take their advice. I do use Synthetic in my aero ones, again on advice of seller. Engines ? I've never had one break yet and all I've ever done is follow Instructions/Warranty.

Run in ? I've done the mineral method and the rich synthetic method, no issues either way, I run on floor till it runs without revs going up n down, then go fly it, reason I don't run in straight away in the sky is, gravity, if it stops in wrong place, model may get broke and the engine.

Stephen Smith 1406/05/2020 18:55:22
237 forum posts

I would never use mineral oil things have moved on. Back in the dim and distant past (late 70s early 80s) I was involved with racing tz250s and 350s which we ran with mineral oils manly castrol R.

Move forward many years and my son followed my lead and went racing, now I know how my perant felt. He raced post classics for 3 years of his racing career this was on a tz350, this was capable of higher reves than the original bikes due to advances in ignition, expansion chambers, porting and combustion chamber. We ran purely synthetic oils in much smaller amounts as little as 50-1 as apposed to 20-1we ran when using minaral but at least doubled ring piston liner and crank life, admitted we ran nicasiled bores as apposed to early hard chrome but the increased life was about the same on all components.

All Topics | Latest Posts

Please login to post a reply.

Latest Forum Posts
Support Our Partners
Sussex Model Centre
electricwingman 2017
Slec
CML
Sarik
Advertise With Us
Latest "For Sale" Ads
NEW POLL - has the pandemic altered your event safety perceptions?
Q: Has the covid pandemic deterred you from attending shows and events in 2021?

 No, I'll be attending just as many as I usually do
 No, but I'll choose my event with greater care
 Yes, I'll attend fewer events going forward
 Yes, I wont attend any where previously I have

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E!