Compression tests on outboard engine

[C08]

I am tidying up a 2012 Tohatsu 20HP extra long shaft engine before selling it. It has only done 360 hours and is running fine (just wanted a bigger engine) but I wonder as I may want to sell it without a physical viewing (Covid concerns) whether compression readings would help confirm it is a good engine? I will have it running on the engine wash plug and show forward, reverse, power tilt up and down, electric and manual start etc. What are considered decent compression readings on a four stroke engine of this type?

 

[CLB]

120 seems to be a figure often quoted for compression, but I think just as important is the fact that all cylinders are similar.

 

[C08]

I suppose 14 psi atmospheric pressure and a compression ratio of say 10:1 with a bit of loss = 120-140psi?

 

[gordmac]

Can you not get a manufacturer's figure? I would say about 150psi, important that cylinders are more or less the same.
Do the test with the throttle wide open and preferably warm.

 

[C08]

Can you not get a manufacturer's figure? I would say about 150psi, important that cylinders are more or less the same.
Do the test with the throttle wide open and preferably warm.

Tohatsu - they do not quote a figure or compression ratio.

 

[QBhoy]

I don’t know for sure, but I’d take a safe bet at 150-160 psi anyway at 10-1 and being a 4 stroke. They are always much higher than a 2 stroke generally.

 

[Seastoke]

If you do know what it should be then it wont help anyone , peeps need to see it running , ps nice advert though.