burtcs

All

What is the longevity of a Norvell, AME or Big Mig either one. A Cox engine will begine to lose RPM as it wears out but this takes years to happen. Istarted to fly 1/2A RC Texico about fifteen years ago and I still using the same engine. These are long flights (maybe 7-8 minutes over and over again)

It seems to me that Norvell start going south in two or three hours. What has been your experience? I don't want to know about crash damage but how long have you run your engine (the agragate time total)?

Regards - Steve B.

ptulmer

My Feedback: (5)

My BigMig .061 lasted about three to four hours. Flights were full throttle, balls to the wall for ten minutes each. It still runs well, but there was a noticeable drop in power the last couple of times I flew it. I replaced it with a TD and gained quite a bit of power. More than was available when the BM .061 was new.

SGC

My Norvel 061 BM has 10+hrs easily enough and still runs strong, I just recently fitted it with an RJL diesel head , have only test run it as a diesel , it started eaasily enough so the compression seal must still be good. Now I run all my 1/2 A motors on 20% nitro fuel with 24% Klotz Castor and have not experianced short life in any engine.
Stewart

ptulmer

My Feedback: (5)

StarGate Command, I blame mine on running it at high RPM and hard. To be honest, that's the only long term experience I've had with a Norvel. Surestart's last better. I use 35% Norvel fuel topped off with Sig Castor. That's approximately 22% castor oil. I should add that it still has good compression and starts easy, but peak performance is gone.

SGC

PT, I dont think anyone would argue that higher nitro fuels give more power but its at the cost of a shorter life, thats why I settled on 20% nitro fuels, its high enough to give good needling and reliable throttling without overstressing the motor, I was running a MAS 6x3 prop and 4 head shims, it still was running fine with the original plug insert too. Another factor in mines good life maybe the milder weather were I was liveing , no frosty morning starts in winter as 99% of days the temp was shorts n T-shirt after 9am, ie 28deg C and rarely went over 32C in summer.
Stewart

chad500_0

Simple question: does any castor oil work or does it need to be "engine" castor? What is the difference?

chad

SGC

Chad,
A simple Q? , thats started many arguments.Basicaly any castor from first press is ok this includes medicinal castor, now a lot/most lubricateing quality castor uses both first and second press oil. This is ok provideing its properly filtered befor bottling to remove gums and debree collected in the extress second pressing, that said Klotz, Sig,Castrol amongst other castor products are known to be good. Also due to the variouse processing methods there is a difference in the amount of polymerisation of castor oil , this basicaly doent effect us MUCH, but it will make a difference depending on the base fuel in use ie methanol, petrol, kerosine, in its ability to mix with the fuel without settling out, I think all castors mix ok with methanol.
Stewart

Bipe Flyer

I break in with 15% nitro and 20% castor, then I use 25% nitro and 20% castor and I find that my Norvels get stronger after a few hours.

gcb

A few opinions:

Castor: Although you can use medical grade castor, it is not quite as good for our purposes and it is a lot more expensive.

NORVEL engines: All of my .049's and .061's are Big Migs. The early ones said they would last 4-6 hours (CL), and "not less than 6 hours" (RC). I THINK this was assuming peak running with ~35% nitro. This was also the ABC version. The Revlites should last longer but in my Big Mig .049 Revlite instructions they have omitted the life expectancy. These engines are several years old so perhaps later they put it back in.

As someone mentioned above, how long it lasts often depends on how well you take care of it. Do you often run it on the lean side of peak? Do you use adequate type and amount of lube? Do you fly in dusty conditions?

Of course, some of us probably pamper them too much. I'm probably in that category.

George

ptulmer

My Feedback: (5)

You know Bipe, you reminded me of something. I don't normally use a bench to break my engines in. I'll run a few tanks out on the ground, then move on to breaking them in during flight by running a little rich. The BigMig broke me of doing that! The first thirty minutes of flight were hairy. I was beginning to think the engine was a POS, but after I started running it at peak, the needle would need to be run in after every flight for the next half hour of flight. The break-in took over an hour! I think now that a bench break-in may have lengthened the engines life, but man did that thing scream. I'll probably stick it on another plane one day. One that isn't intended to be ran at high speed and RPM. Still plenty of life in it.

eroc144

My Feedback: (1)

I've got a couple of .061s (revlite) that are several years old and have over 10 hours of run time, mainly at WOT. They're as strong now as they were after break-in, at least according to my tach readings and I run 25% nitro and 15-20% castor.

3 - 4 hour total runtime seems awfully short for these engines. A 1 oz tank gives roughly 8 mins/flight, so that's only 20 - 30 flights total before the engine dies. If you're only getting that lifespan out of these engines then you're probably running too lean or doing something similarly harmful.

EG

Remby

My Feedback: (3)

O.K, I read somewhere in the old R.C. mags that cox tested the engines for this, and they quit testing after 300 hours because it was still going strong. I also just checked the flight log from last year, I keep records for this purpose of engine use. The one Cox had 6.5, and the total for both I flew on was 17.1 hours, in 2006.

This is for the Cox engines only, and know the total is correct, and these engines are going into the third and forth seasons. 25% nitro, a bit more added castor to around 21%. Still going strong, so perhaps the cox last longer? Haven't had a failure as yet.

digital_trucker

One reason for Cox durability is the steel liner/steel piston.