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What is the life expectancy of a properly cared for Nelson Quikee engine? I have heard onlt one season. (4-5 races?) If when it does wear out how much is a replacement piston/sleeve or bearings?

Ed Smith

With emphasis on the "Properly cared for"

I have an eleven year old 428 engine. It is all original. Sure it is past it's prime now, it is about 500 rpm down from where it should be, but it still runs good enough for practicing and testing new airplanes. It certainly cannot wear out anymore, nothing is touching anything inside.

This long life is not unusual. I have six 428 engines all of them have been well used and well cared for. The oldest is 13 years old and has a definite death rattle. Then there is the eleven year old one. The next oldest is nine years, then two at two years and the youngest I got last year. I ran them all at the end of the season last year to compare performance. That test afternoon sure dispelled a lot of the BS floating around. I used Powermaster fuel and an APC 8.75 x 9.0 prop. On the same day under the same weather conditions with the same prop and fuel the poorest performer was the oldest and came up to 19,200rpm. Two of the newer ones came up to 19,600. The others were in between.

I have five Q40 engines. The oldest is nine years and the newest are two years old. Under the same test conditions as the 428s the rpm range from oldest to newest was 22,600 rpm to 23,200 rpm with the APC 7.4 x 8.0 #2 carbon prop.

I break my engines in properly ( I am not going to argue about that procedure). I maintain them throughout the year and at the end of the racing season. I use the aluminum sleeve in all of my engines.

A new piston /sleeve will cost about $90.00. However the rod and wrist pin will probably need replacing at the same time. Total cost will be close to $140.00. It is a long time since I did that.

Ed S

daven

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I've used the same Q500 motor as my primary racer (6-7) races per year for the past 6 years. Original piston / Sleeve / Everything. I may have changed the bearings, can't really remember for sure. I do a pretty good job breaking them in, but I run them pretty close to peak.

Its just starting to loose a little RPM, but it did a 1:08 two weeks ago, so its still competitive.

vertical grimmace

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Thanks for the info guys. I have an N36 combat engine so I am familiar with the quality but I have never owned a N40 quickee. I am getting close to purchasing one though. At the last race I was at I just heard some guy complaining that his would only last one season! That seemed to speak more about him than the engines but I wanted to get some other thoughts.

redfox435cat

if you do replace the bearing go to boca bearings and get a set of ceramics. the motor runs a heck of alot cooler. I wore out one Jett, that was me running it too lean. anything to win right, and I did, tough at that point I didn't care about the motor since it was about 5 years old. I have to try a nelson one of these days, allot of money though

daven

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Actually, I would stick with the Nelson stock "Swiss" bearings over Boca.

[email protected]

buy one good motor once, rather than three average for the price of a good nelson, or for that matter a Jett- learn to use it properly and you'll have a very good engine for a long time. Keep with the bearings as supplied- I have no experience with Bocca, but my experience with the swiss bearings is only good- why change brands...........trevor h

Ed Smith

Properly fitted bearings will have no influence on the heat of the engine. Considering the quality, longevity and performance of the Nelson engines I would stay with original equipment when replacing parts. To change the type of bearing is like saying that Henry does not know what he is doing!!

Ed S

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What about a used Nelson? Worth it or no?

Ed Smith

I would never buy a used racing engine. Does anybody sell an engine that is performing the way it should. If, for whatever reason, you have no choice then make sure you do NOT buy it from somebody who says the engines last for only one season or puts Bocca bearings in it to keep it cool.

Buy a new one. Take advice from real people who know how to operate them and you too could have a good running engine for the next eleven years!

Ed S

BUDMAN27

New old used Bocca stock bearings I could care less just as long as it goes fast and turns left.

grubs4flyn

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I just got two Nelson Q 500s used at a good price. What would be the acceptable RPM with what prop to be competitive?

bl10

On the west coast most of the FAST guys are turning the 8.8 x 9.25 19200 to 19800 on the ground. It takes a pretty good engine to do that. My latest nelson, about 6 months old, turned the 9.25 19900 to 20k two weeks ago. My next best engine, about a year old, pulled the same prop 19500. I know it sounds like a lot but did it with three different props and two tacks. Thinks must of been just right. As far as I know the vast majority of the west coast guys run the 8.8 x 9.25 except Fred. He uses the 8.75 x 9.5NN.

Take it for what its worth but I think the really fast guys freshen their stuff fairly often. I'm not one of the fast guys but change top ends , rod, piston, sleave and head, at least every year. I change bearings, I only use those supplied by Nelson as I consider the Bocca steel bearings marginal and the cremanic ones junk, when I detect any roughness at all.

I also make sure my stuff is always updated to the latest revision. There have been many small changes to the Nelson over the last few years. I'm not sure the changes helped the Q40 engine but the Q500 engine seems stronger now. We had two guys lower the national Q500 record at our APR race and several others run really fast.

Barry

daven

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Grubbs,

In your weather, it may be tough to spin the 8.8"x9.25.

The one prop you can never go wrong with is the 8.8" x 8.75 this prop will work in just about any condition. It is not quite as fast as the 9.25, but it makes up for it with a faster first lap and does not lose as much speed in the turns.

My engines are competitive with most out there, and on average, my good engines peak about 19,600 with the 8.75 and only 19,300 with the 9.25. Thats the top rpm after a pinch of the fuel line.

IF I can't get 19,300 with the 9.25, I will run the 8.75.

I rarely change top ends, but have been cleaning carbon off the top of the piston and head after every 10-15 runs.

DMyer

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Those west coast guys got all the good air! In the muggy east coast sea level air we don't see quit as many RPM's. I only change my bearings when needed... swiss OE as Mr Henry Nelson intended.... if they are smooth... they are smooth... you will know when it is time and or/ you put a chinck in the front bearing with a terra firma bath. I replace the whole top end every 3-5 year years if needed... sometimes longer. I still have my orginal Nelson from the original batch!.... good enough lifespan for me!

garys

I don't freshen up my stuff that often, and, like Fred, I also run the 8.75x9.5NN (ask Fred who got him to try that one?). My two primary Q500 engines are 1.5 and 2.5 years old, and have never had the cranks out of them, and rarely even had the piston/sleeves out of them. Fortunately neither has had the misfortune of being crashed. Both will turn the 9.5NN anywhere from 19,700 to 20,000 (got to love our west-coast air), unless it's cold, then one is about 1-200 slower (it's still a little tight). As far as maintenence, I oil them up after a weekend of racing with Performance Specialties Ultra Oil, straight into both bearings (I remove the drive washer and backplate to oil them), and put them in a ziplock bag until the next race. My oldest Q500 engine will still turn the 9.5NN over 19,500, and the piston/sleeve on it is about 5 or 6 years old.