Cool After All These Years

[spartonboat1]

I just did a technical detail of the engines and engine room, J&T 6-71N's in a '72 43'DCMY. This was followed by a two day move of the boat from St. Ignace, MI, where it had been on the hard, and to Grand Haven and our new moorage. The detailing work took 5 weeks of 2 days each weekend, requiring 9 hours of road trips to and from site; very hard work, but was satisfying. I was able to run a steady 13.8kts at 2,200, vs. the 12.7kts at 2,150rpm I have traditionally run; see higher Air Box pressures, plus cooler temps below. Day One Flat Calm Mack City (fueled there) to Frankfort. Day Two steady 10-15kt winds and 2-3' seas, some 4's. Decent ride, thanks to these vintage Hatt hull forms.

The Air Box Ports have had 3 or 4 bleeding on each engine that were blowing all over, so I pulled them and found bad/missing pieces gaskets. Installed new ones from WW Williams. So no more bleeding, but also higher Air Box pressures, which these old 6-71N's love.

The right hand engine (stbd) has always tended to run warm, not hot, but didn't like to be pushed to 2,200, without nearing 180 degrees. Well I finally took care of two cooling system hoses configurations, and after 11 years of ownership, she ran steady and cool at 2,200rpm, during two 8hr long runs. Cool is about 170-175 degrees indicated, instead of a little below 180. So pleased about that.

The oil cooler was fed by a fitting that faced the wrong way and kinked the hose. I decided it had to go, so removed the offending fitting, in the process damaging it, so installed a new one in bronze that lines up nicely. Hose looks happier with no kinks, plus attendant better cooling.

Next was the hose from the top of the Stbd Jabsco Pump up to the Heat Exchanger. The fitting on top of the pump faces away from the HE, (Port pump fitting faces in correct direction) so a major kink occurs, no matter what type of hose is used. I finally resorted to installing an "ell", in place of major bends in the hose. No more hose kinks, but two mild curves!

I hereby admit I resorted to a "flanged on both ends" Ace Hdwe gray plastic "ell", intended for farming water systems, but it has been solid, since it only carries cold water for which it is rated. Also watched it after shutdown, when the ER gets hot after shutdown, but again, the ell fitting stayed solid and did not get flexible. I am seriously considering having a copper fitting sweat-fit fabricated from several parts by a plumber, so that hoses would only be needed for each connecting end.

So who knows if anyone is interested in my cure, but I was pleased to see her "cool after all these years!" (since 1997).

 

[Boatsb]

I replaced a few likes with hose last year because the pipes were going bad. I have copper tig welded into flanges where I needed a hose barb and had a spacer made for the pump outlet to allow it to clear the manifold and go straight to the he. On the output of the he I have a y made from copper to split the water to both sides of the boat collector and I put a ground wide on it for electrolysis protection. To make a long story short I went from pipe to nose and had great results. Fwiw many of the pipes are not available so it was not just an experiment but a solution.