Compression numbers for 2003 Honda 225 hp outboard good?

Flbeachfront

Recruit
Joined
Apr 7, 2015
Messages
1
Here are readings the mechanic took today, motors were cool temperature when performed. Looking to buy this boat, yet would like someone that knows motors to provide feedback, data showed roughly 580 hours of drive time when data was downloaded. No codes are active. Port engine history had showed 12 oil pressure alerts, 2 temperature alerts, yet who knows these could have occurred years ago.

Port engine cylinders 1 thru 6 in order 195, 190, 163, 185, 180, 185
Stbd engine 1 to 6 in order, 200, 200, 180, 183, 195, 195

Any feedback is helpful
 

hondam

Petty Officer 1st Class
Joined
Nov 21, 2013
Messages
213
12 oil pressure alerts concerns me, need to check crankshaft endplay. Engines not broke in properly can have thrust bearing issues which first show up as low oil pressure alerts. Temp alerts not a big deal.

Compression tests can be misleading sometimes on these engines, if you do not full open the throttle body and have a good charged battery with very clean connections you can get bad readings. Leak down tests are a much better indicator of mechanical health.

The port engines numbers are off, definitely need that leak down test. Could be nothing, could be something, don't know without the test.
 

MattFL

Master Chief Petty Officer
Joined
Oct 20, 2010
Messages
845
That one low cylinder would concern me, especially when combined with oil pursue warnings. Leak down test isn't a bad idea. Also have the valve clearance checked on that low cylinder (assuming not hydraulic lifters) and get a scope in there to see if the cylinder walls show anything interesting. Overly tight valves could definitely reduce compression and that's an easy fix, but the cause could easily be more serious.

Oil pressure warnings and temperature warnings would concern me, I would personally consider that the motor may need major work in the future when making an offer on the boat.
 
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hondam

Petty Officer 1st Class
Joined
Nov 21, 2013
Messages
213
No lifters it's a over head cam engine with locknut and screw adjusters. There is a lot that can throw off compression like the adjustment and timing belt that's why the leak down is more useful because if gives an idea of the condition without all those other factors to consider.
 
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