Andy's Model Engine Repair
Your Subtitle text
Andy's Model Engine Repair
Welcome to Andy's Model Engine Repair Website.

Model Airplane Engine Repairs and Reconditioning

I will repair or recondition any two or four-stroke model airplane engine, glow or gas, single or multi-cylinder. Four-stroke engines are my specialty. I can also do machine work and employ various welding methods if necessary for the repair. Such work as the following can be done:

-Restoration of stuck and frozen old engines that are otherwise sound to good running condition (see photos)

-Bearing replacement, two or four stroke.

-New piston rings, including cylinder honing.

-Removal of frozen bolts or screws without damage to the engine.

-Complete engine rebuilding to restore performance.

-Damaged engine repair.

-Straightening of most single-cylinder gas two-stroke crankshafts, and some  others, depending on amount of the bend.

-Glow Plug 1/4"-32 thread restoration (Helicoil) in stripped cylinder heads, two -stroke or four-stroke. These are done on a straight labor-time basis with a $25 minimum, which is generally all it takes.

-I am not currently set up to do broken exhaust port repairs. Clarence Lee still does these using a threaded brass insert. Call him at 818-352-3766. 

Since I have to buy them at retail just like you do, there is no markup for parts and I will use yours if you have them (assuming they are correct). Shipping costs for parts is also a pass-through. Bearings will come from Boca Bearing, other parts will be ordered from the appropriate distributor.


Labor for any skilled service is $25/hr, clean up using an ultrasonic cleaner is billed separately at $10/hr. A typical two-stroke bearing replacement in an otherwise mechanically good engine will take about an hour or less, including light cleaning, plus roughly $15 to $30 for the bearings. The cost of cleaning is impossible to predict but generally runs about  $10.

Four stroke engines, by virtue of their far greater parts count, require more labor for almost any repair. A tear down and analysis of a typical four stroke will require close to an hour's labor depending on the make. Smaller engines (under 1.0 cu. in.) tend to be less cost-effective to recondition if corroded or frozen than larger ones since the labor is the same regardless of size, but the engine's value is much less. Something straightforward  like bearings, piston rings or a connecting rod replacement is pretty much the same regardless of size. Obviously there are more parts to clean in a four-stroke, running around $20 and up.

I will give you a rough estimate after seeing your engine, but I don’t always know what I’ll find until its apart. Often an older engine that has not been used in a while, or has not been properly preserved for storage will be frozen and damaged by corrosion (especially four-strokes and even if you live in a very dry climate, (see photos) to the point that restoration of all the parts will require labor costs in excess of the engine's worth.

If I feel its not
repairable, or the parts or labor cost will be excessive, I will not proceed further without discussion and authorization.                                                        
Often its cheaper to replace than repair. If that is the case, you will only owe me for my time to tear it down, generally less than an hour unless there are broken fasteners, etc.


A Money Order seems to be the easiest and least costly way for most people to manage payment, at least in my area. Our local supermarket charges $0.89, for example.


All work is guaranteed for a period of 90 days from receipt. (No comebacks to date.

Don't overheat or over rev your freshly repaired engine and expect me to fix it for free. I can tell when they've been abused!

Call me or e-mail to discuss your engine problem.

Andy Johnson

Call me at 561-395-4179 or,


Does your engine look like this?

An older Saito120 from Nevada, put away wet with no after-run oil; no compression, lots of corrosion, and from a dry climate, no less. This is a very typical situation with old, and not so old, four-strokes.

And this? Notice the stuck-open valves and far pushrod out of the rocker arm. Not much compression here.

Here's the reconditioned engine. This level of restoration required quite a bit of labor, but even with new bearings, far less than the cost of a new engine, and it ran like new.

To avoid having your four-stroke engine look like this one did, run all the fuel out of while its still good and hot and at a moderate throttle setting, not at idle. Use a good after run oil, or a fuel containing some percentage of castor oil, or both. It is remarkable how much moisture is retained in the crankcase of a four-stroke even after running it dry while hot.

Four stroke engines do not purge the moisture from the crankcase as well as two-strokes, nor do they run as hot in the first place. Its still a good idea to run a two-stroke engine dry at the end of the day.

Gasoline engines, particularly two strokes, run very hot and since gasoline does not have the affinity for water that alcohol does, there is less moisture trapped in the crankcase and it easily vaporizes. I have never seen corrosion in a gas engine that was properly cared for.

A gas engine should be run dry if it is to be stored for more than a month since the fuel will dry out in the carburetor and eventually cause varnish deposits that can plug the very small orifices in the carb.
Web Hosting Companies