Evaluating used equipment without hour meters

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muddstopper

muddstopper

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I think a compression test is a good ideal and easy enough to do. What is considered good compression of a small, 5,10. 15, 20 hp engine. With a pull start engine, I can get an ideal as condition by pulling the rope, with electric start, pulling the plug and installing a guage is a good ideal.
 
T. Mainus

T. Mainus

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Compression test. We bought our new to us Powersplit last summer. Started fine and ran fine but as soon as it got cold it wouldn't start. Compression test showed little to no compression in one cylinder. We still would have bought the splitter if we had known that ahead of time, but at least if you know you can use that as a bargaining chip on price.
 
WoodTick007

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Keep in mind that many small engines have a decompression device or attachment or whatever the **** you want to call it which makes it easier to start. More often than not and once the engine hits a enough RPMs it bypasses the decompression whatever you want to call it. So that being said some engines may show lower compression and initial starting. The other thing to take in mind is how many compression Strokes or Revolutions of the engine would be required to get a accurate compression reading. I would contact the engine manufacturer and inquire with those questions before attempting t o perform a compression test.
 
rancher2

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If this item is a private sale and not some jockey reselling a item. As I drive in I look around the place and see how well things are kept, is every thing in a shed. What is the reason he is selling it. If the place is kept up usually that item has been well cared for. If it is a splitter how worn is the rest of the splitter. If it is cold out and the item is still warm it probably doesn't start good in the cold and the owner made sure it was warmed up before you showed up. If I am worried about the motor I make sure I buy right or just walk away. But some times if the item is rare you may have to take a chance. Like others have stated a compression test is good if the motor doesn't have a automatic decompress. I have done it on the v twin engines by pulling one plug and running it on one cylinder to check the compression of the one cylinder then do the other.
 
blue924.9

blue924.9

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the correct method for testing small engines is a leak down tester. You apply regulated air 100 psi typically while holding the engine at top dead center power stroke so the valves are closed. This not only bypasses compression release you can also figure out where the leak is if there are issues. Rings out the oil fill and valves out the exhuast or intake.
 
rarefish383

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On something like a 22-30 ton splitter I would have them run it wide open for a while. If they won't something is wrong, they are made to run wide open. I would also hope for the best and plan for the worst. If it's a 6.5 Briggs or the like, just plan on putting a 6.5 Predator on it for $100. Most anyone selling something will come down $100 from asking price. Like Blue said a leak down test will help. But a visual will help too. Check around the dip stick to see if the top of it is slick with oil or all black and dirty. Bad rings will blow oil out the breather or dip stick tube on small engines.
 

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