compresion

[cterrebonne]

Originally Posted by Skools Out

that's a worn out motor should have more compression than that, more like 95 up in compression. i'd steer clear or plan a new set of rings for it. it must have a ton of hours like in the 3500 to 4000 hr area.

either that or your gauge is broken, i dont see a carbed engine lasting that long. but hell you never know.

[spareparts]

cehck it with another guage, I have four or five compresion guages, teh most expenisve one I own reads 10 psi low, the cheapest one reads 5 psi high( I checked than against a high doller set of liquid filled German manufactured pressure guages). Usually if they are close to each other, they are OK. I've never seen an engine equally worn out on all cylinders, usually, one cylinder lets go first. But I guess it cousl happen. Take the boat for a spin, see if it turns up rpm(check your tach also)

[Skools Out]

it sounds like one of the twin 1990 Johnson 140's i bought from BR that had according to the hr meter 3890 hours on it. that motor reads between 62 and 68 psi on all cylinders it actually runs just hard to start at times.

[swampbilly 1980]

I've got a '84 150 Johnson and the compression was around 85-88. They told me that it was "worn out" but, she runs like a clock. 30mph@5200rpm . She could blow any day, but heck we'll use 'er 'till she dies For $2500.00 boat motor and trailer I couldn't go wrong... and I know......