Norvel break in

Hi guys,

Today at the circles I was watching the big guys mix up their high nitro fuel and fly their carrier planes. Getting ready for the Nats, I assume. Got inspired to do some engine testing.

I finally gave up on the C*x reed valve engines and am using the Big Mig Norvels for sport flying. Problem is that they are very hard to break in. I have to heat the cylinder with a heat gun to get it loose enough to turn over. I have heard the stories of broken rods because guys try to force the engine past TDC. After a half dozen runs still too tight. I don't like making noise around the neighborhood and the flying circles don't have extension cords for the heat gun. No, I am not to be trusted with a propane torch.

My solution was to take the head off, heat the engine till it turned over then coat the insides with "Liquid Rubbing Compound" with a Q-tip. Stuff you use to clean off the oxidized paint in the days before clear coats. Then I spun it up with the electric starter. Worked great and now I have a usuable engine. Looking back, would toothpaste be a better substance?

I have a half dozen Big Migs, some new, some a few years old. They all had the same tightness at the top of the bore. Once they are freed up they work fine and I never have dirt issues with the reed valves. And they don't mind electric starters. Haven't tried hand starting.

John in Kalifornia

LAST EDITED ON Jul-03-04 AT 10:25 PM (CDT)
 
Hi John,

The Norvel engines are fitted at the factory with a supplied "tightness"
and Norvel recommends a specific break in procedure.

I have purchased 6 Norvel engines and have followed the factory supplied
directions for break in to the T. I recommend not to rotate the the prop until I follow
the Norvel instructions.
Norvel recommends to remove the glow plug and lubricate the cylinder/piston assembly with a few drops of a high quality machine oil, allowing the oil to cure 24 hours with the piston at the bottom of the cylinder. Then Mount a prop on the engine and quickly turn it at least 100 times by hand or with an electric starter.

The extreme tightness will lessen.
After that, for break in I use 15% nitro fuel. 22% oil (50% synth 50% castor).

Other gents will chime in here.

Paul Heimgaertner;)

p.s. this should help in providing more info: http://www.norvel.com/tech.html

bigR,

I have only run across one Norvel that actually required lapping. In my case, I dabbed some oil and aluminum oxide on the cylinder with the head off, rotated the prop back and forth with engine inverted so it would not run down into the crankcase. When the prop would turn over completely, still with lots of resistance, I stopped. Make sure you THOROUGHLY clean out all lapping residue before running it.
The first runs had extra lube to carry off any residue that remained, followed by normal break-in.
That was emergency treatment, however. I would suggest doing as NORVEL reccommends and let oil sit in it overnight. You might find that it will turn over if flipped fast but almost lock-up if turned over slowly. This is normal.
This is only my experience. Individual results may vary.

>Hi guys,
>
> Today at the circles I was watching the big guys mix up
>their high nitro fuel and fly their carrier planes. Getting
>ready for the Nats, I assume. Got inspired to do some engine
>testing.
>
> I finally gave up on the C*x reed valve engines and am
>using the Big Mig Norvels for sport flying. Problem is that
>they are very hard to break in. I have to heat the cylinder
>with a heat gun to get it loose enough to turn over. I have
>heard the stories of broken rods because guys try to force
>the engine past TDC. After a half dozen runs still too
>tight. I don't like making noise around the neighborhood and
>the flying circles don't have extension cords for the heat
>gun. No, I am not to be trusted with a propane torch.
>
> My solution was to take the head off, heat the engine till
>it turned over then coat the insides with "Liquid Rubbing
>Compound" with a Q-tip. Stuff you use to clean off the
>oxidized paint in the days before clear coats. Then I spun
>it up with the electric starter. Worked great and now I have
>a usuable engine. Looking back, would toothpaste be a better
>substance?
>
> I have a half dozen Big Migs, some new, some a few years
>old. They all had the same tightness at the top of the bore.
>Once they are freed up they work fine and I never have dirt
>issues with the reed valves. And they don't mind electric
>starters. Haven't tried hand starting.
>
>John in Kalifornia

Ron B.
F4Fguy

You may have a useable engine for now,but you've just used up about 80% of it,s normal lifespan.These engines are designed with the "pinch" at the top,with both sleeve and piston tapered,so that,at normal running speed and load,both piston and cylinder are straightwith minimum clearance.If you lap them straight at room temperature,they will be loose at running conditions.This may even give a little more power (for a while),but it will increase wear dramatically.

I got a new Norvel and broke it in per the advice of Ron B. and from the Norvel web site. I put a heavy weight oil in the engine and let it sit over night. Then I flipped it over about 200 times, (web site only said 100, but I found out that the black part is not grounded to the head when I first tried to start it.)
Any way long story short, follow the advice from the experts and the Norvel web site.
I now have an engine that runs and starts great!

Thanks
Paul

I bought a Norvel 061 from the factory in San Luis Obispo (home of my Alma Mater, Cal Poly). Before flipping it over, I heated the cylinder with a hair dryer until it turned over OK. Then, the first runs were 10 seconds or less. It didn't take long to break in and it seems to be just fine.

Having had good luck with this motor, I ordered a Norvel 15 and it was not stuck tight. So ordinary short runs got it broken in pretty quickly.

>I got a new Norvel and broke it in per the advice of Ron B.
>and from the Norvel web site. I put a heavy weight oil in
>the engine and let it sit over night. Then I flipped it over
>about 200 times, (web site only said 100, but I found out
>that the black part is not grounded to the head when I first
>tried to start it.)
>Any way long story short, follow the advice from the experts
>and the Norvel web site.
>I now have an engine that runs and starts great!
>
>Thanks
>Paul
>
>I am a retread, - I did C/L in my youth and did not know
>what I was doing then other then having fun. And not much
>has changed.

Ron B.

Paul:

Thanks for the plug.Sorry I forgot to tell you that the black anodizing on the cylinder is a non-conductor.You either need to use a plug on connector or ground to a bare aluminum part of the block.The plug on is easiest to use but some of them won't stay on the Norvel head,and you have to hold them in place while starting.

Ron B.
F4Fguy

Hi again,

Thanks for the tips. I have another Norvel that I have been soaking in oil for a couple of days now. I'll try again tomorrow following the @$&*# directions, as they say. Yeah, I probably have shortened the life of the engine considerably by overlapping, don't mind; at least it will run now. I found out that these engines run very steady once broken in, even if they seem worn out. One nice thing about the "looser when hot" piston/cylinder fit is that they start to slow down when overleaned out and don't just sieze up and quit. Yes, I guess I'm hard on engines but am not out for the last bit of performance. Just sport flying.

Mister impatient in Kalifornia

Shhhhhh!

I wish you guys would stop spilling the beans! If John wants to "break in" his Norvel real good...that's ok, isn't it? He was talking about "mebbe" building a 1/2A racer and using the Norvel. Now the two guys that he an ol' Mikey'd be flying against have Cox reed valve engines.... So if the rest of you guys could stop helpin' so much, me and Mustang Bill would appreciate it!

Thanks for pitting for us yesterday John and Mikey. And congrats on some fine (first) horizontal eights, Mikey. I KNEW them spots on the SuperClown would make it turn tighter!

Dave
LA_Flyer
Manhattan Beach Speed and Racing Team
Internet Racing League

PS-The LA carrier boys showed up after you left for one more practice session. They put in some more slow flight practice in the wind. Talk about maximum stress....

Hi, this is a problem with Norvel engines, I found that I used there fuel tank mount with the spring starter to get my big mig going. I have owned about 5 of their engines so far. I also have the .07 they make and I think it was the worst of all to try and start. But I put the oil in my .061 and then with the aid of the spring starter it started up and then was okay. I like the Norvel engines as they run well and all. Here is a question for everyone also I was thinking on the .15 C/l engine they make if it is like these smaller big migs I am not shure I want to try to get a engine of its size to start when new as it is trouble. Now I own of the first Norvel .061 engines before they were the Revlite models, I think it started right up but they soon went to the newer cylinder material which is when I noticed you could hardly turn them over. I don't know for price etc. the Norvel .049 and .061 is hard to beat but the Cox TD is still my favorite. So basically though I think with the tank mount with the spring starter it should get most of the .061 size engines started without the risk of a electric starter and then they usually will just flip start, I also noticed that if you don't watch or use Norvel fuel it is very easy to flood these engines as well which will give trouble as well when first starting them usually just a few drops of the Norvel fuel is all you want to use in them this might help as well. I am not shure how long a Norvel engine will last, I have only run at the most so far about 2 quarts of fuel through one of them I own here. One thing I will say is that I do not like the carbuerator mounting on them though I had crashed one plane with one of these engines and the carbuerator loosened up then, you could wobble it around in the carb body after, these are just some things I have seen with them so far and not to say anything all that bad about them what it did was egg shape the hole through the carbuerator so that the bolt could not hold it as snug as when it was new the engine still runs like this but probably hurts its performance also after. Anyway this is just a few things I have encountered.

Colnago,
The pre-Revlite carbs/venturis on the .049/.061 were held in with epoxy. Some seal the Revlite models with a little silicone when replacing the carb or venturi.
I have two Big Mig .15's and one AME .15. One was VERY tight but I kept the faith and started it with a firm flip. All run well.
You may notice with a new Revlite that it appears tighter if you turn it over slowly compared to flipping it fast.
I would not hesitate to get another of any size.
Just my HO.

Hi George thanks for the note on the .15 Norvel, I was wondering if they were so hard to start as well. I did notice the new revlite engines were different, they are a improvement over the first engines they made, I had talked to Norvel a few times over the phone when I had first tried their engines. What fuel are you running in the .15 if I might ask ? just curious as I would imagine you could run other fuels besides the Norvel fuel in them. And what glow plug have you tried? Just some ideas on what might work well with one as I have been looking at getting a .15 for quite sometime from them here. Thanks Colnago

We are using the Norvel BigMig 15 against Fox 15 bb's in the local Scale race II races. Keeps right up there for a just took out of the box and run engine. 10% fuel is the limit for the races.

LAST EDITED ON Jul-09-04 AT 07:46 AM (CDT)
 
I have not run the .15's extensively. I used NORVEL's 15% with some added castor for break-in. Any good fuel of 15% or so nitro should work. You might consider ones on NORVEL's list. The Revlites do seem to run a bit cool so if you get fouled plugs you may need to eliminate rubber like the smaller ones. I don't run mine hard so that may make a difference.
Haven't optimized for a plug yet. Tried both short and long cool. Both work. I tend to prefer the Swanson short cool so far.
I think NORVEL introduced Revlite with their .15. Later they added Revlite to the .049 and .061. At least I've never heard of a per-revlite .15.
One change I think they have made in the .15 since I got mine is that it appears that the head can be held with their spanner while tightening the plug.

George

The NORVEL .15 is a good match for the Flite Streak ARF. Some would prefer "more cubic inches", but the motor pulls the FS right along on 50' lines. I'm considering going to 55' lines. Enough horsepower to do the job.