cervelott

When buying a used engine what are some of the specifics to look for without being able to bench test
or see the engine in action? Obviously rust, cleanliness, and compression come to mind, as well as any signs
of damage.

DadsToysBG

My Feedback: (35)

Allow enough room in the price to have it repaired without going over the new price. Know the brand of the engine. My price is about 50% of new. Anything higher and I will buy new. I have one gas engine that is pushing 20 years and have only had it worked on twice. It has reached the point where I will have trouble getting parts in the future so the next time I'll have to buy a new one. I guess one new engine every 20years isn't that bad. Dennis

safeTwire

My Feedback: (2)

Look through the exhaust port, and check the piston and cylinder for scores, or scratches, running vertical or up and down.

If it's a "Ringed Engine", use the end of a wooden popsicle stick cut square ( Never use a metal object! ) and press on the piston ring. If the ring is NOT broken, you will feel the "spring" in it. A piston ring's "spring" feeling is very slight, but it will be there.

Inspect the glo plug threads in the cylinder head.

So... Bring the tools needed for muffler removal, popsicle stick, glo plug wrench, and if you eyesight is like mine (which I hope it isn't )...a flashlight and magnifier!

Keep in mind that an engine is the "Heart" of any machine!

Mr67Stang

The person's sales reputation! A person with an excelent, well established reputation will more likely want to protect it. While a dirtbag won't care.

alfredbmor

I have bought about 7 or 8 engines through ebay, two of them (Saitos) had to be repaired at my expense, even that the seller claimed that they were in top conditions.
The first one, a Saito 72, needed a new carb, a ring and bearings, after repairs the cost of the engine and parts could almost be the same as a new one (I just do not want to know exactly how much I spent as I was having a great time learning how to repair it).
The second one, a saito 1.00 came like new, never used but the crankshaft were bent (a kind of 70 dlls for the crankshaft and maybe I will have to replace the bearings so this can go up to a 100 bill.
All other engines performed flawlessly.

Spacemonkey71

you might want to look at the condition of the heat sink on cylinder. If it's banged up and/or chipped, it may have been crashed and there could be some internal damage... also, if you can get your hands on it before you buy it, spin the output shaft and listen for a good compression sound (like the sound of an engine running REALLY slow, a solid "Pop" sound)

Also, make sure that the needle valves are all in place and WORKING; these are often damaged on used engines. And make sure that the carb opening slides smoothly FULLY opening and closing without hanging or hitching.

Pull the glow plug and see if it's burned to death too. If it looks like it's been rubbed over with a sharpie and resembles a charcoal brickette ("crusted") the engine has been leaned out ALOT and burned the plug to a cinder. That ain't too good. Leaning out the engine is rough on the WHOLE engine and IS NOT GOOD. On the other hand, if it's kinda greasy/oily and slick feeling, it may have been run rich (which isn't as bad, but it's something to be aware of).

Until you put a prop on it, hook it to a tank, hit it with a glow-plug starter and make it go BUZZZZ!!!!!!!!! you may not really know. It's difficult to tell alot about an older engine without disassembling it and looking for stuff like busted rings, burned cylinder walls, cracked pins, warped parts, etc...

Old engines don't mean DEAD engines though! I've got a Webra 10ccm (.61 ci) that's from the 1970's and hadn't been started in at LEAST 10 years and it spun up like a champ in no time flat and pulls like an OX!