Home › Forum › Ask A Member › Top speed with 18hp Evinrude on 14′ aluminum › Re: Top speed with 18hp Evinrude on 14′ aluminum
January 12, 2017 at 11:46 am
#50877
quote BillW:
There are a lot of possibilities but I would start with the compression. I have found that 18s can be all worn out and still idle like a watch. They will start instantly and yet have no top end. A good 18 should have 120 psi compression or better.
The seller listed the powerhead as having 118psi per cylinder I believe. My gauge showed 100 I think. My gauge might be reading low. I need to try a few more gauges. Both my old powerhead (which I never had running correctly) and this powerhead have score marks on the sides of the pistons that you can see, if you remove the plate by the fuel pump.