I am looking at buying a sea ray center console, it has a mercury 135hp black max. I was wondering if anyone know what the factory compression rating was or is, so I can compare it when I do the test this week. Thanks
I am looking at buying a sea ray center console, it has a mercury 135hp black max. I was wondering if anyone know what the factory compression rating was or is, so I can compare it when I do the test this week. Thanks
We're going to need a serial number to give you an accurate answer. If it is a part nr 884-9765 block and has compression reliefs in the cylinder walls at the top of the exhaust ports then it will produce about 110lbs fresh. 105 would be normal for a worn engine with decent life remaining and 100 is time for a tear down.
That's all assuming that no custom work has been done to the engine.
well thanks for the info but the guy sold the boat from under me. I found another boat but it is 18ft with a 70hp evinrude 4 stroke. Is that boat under powered? I am going to test drive it but it sounds underpowered to me
well thanks for the info but the guy sold the boat from under me. I found another boat but it is 18ft with a 70hp evinrude 4 stroke. Is that boat under powered? I am going to test drive it but it sounds underpowered to me
My 18ft campion had a 70hp on her and she ran ok. Not the fastest boat by any means but never had a problem getting on a plane with 4 people and loaded with camp gear.
It might be a little under powered. It all depends on the hull design and loaded weight. Usually, 18' pleasure boats are max power limited to around 115. Check your USCG plate for power rating and that will give you a better idea of what power it should have.
I don't know if there is some set rule or not but in general I've seen most boats powered by dealers at about 90% of max rated HP.
