Water lock questions

F

freddyuk

Well-Known Member
Joined
2 Sep 2012
Messages
127
Visit site
Boat was delivered last year and had steaming exhaust only after 7 hours running at 2700 revs. Have been servicing to eliminate any obvious problems. Nanni 200 (1986) engine has been sitting idle since last year. Fuel system filters replaced (primary dirty / secondary clean). Oil changed. Water pump replaced. The temperature sensor is located on top of the engine and I noticed the cable connectors were very loose as this is where anyone leaning on the engine would bend the connectors causing damage. I will replace the spade connectors and check its secure.
I started the engine yesterday after draining and replacing water to fit heating isolators. The water had antifreeze in it and was clean.
Engine idles fine and oil pressure was 60psi and slowly dropped to around 40psi as it warmed up. I was checking around the waterlock and could hear a whistling noise from this unit (plastic) and also noticed it was slightly flexing enough to vibrate the plywood it was secure to. I know nothing about these systems so is this normal or could this be part of the overheating issue? It was only warm at idle. Is it worth dismantling to check its not restricted? The overheating on delivery only occurred as we went from a beam sea to a following sea right at the end so I wonder if this was part of the cause with the exhaust being below water or just a fluke.?
 
It was not steaming when we left and we were taking photos off the stern so sure it was not steaming when we were on passage but as soon as I turned a corner after 7 hours in heavy swell I noticed the steam. It was a new boat to me so was watching temp/pressure/revs. Never went over 12\15 knots / 2500 +/- revs as heavy going. Temp was OK around 75c. Next passage was to marina for the winter. Steam started fairly quickly. Again did not push it as was choppy but when it calmed down I increased revs and the temp rose to 80c+. Also the throttle was not responsive over 2800 and no more speed available. Decreasing revs to 2500 dropped temp back to 70's. Maybe fuel blocked by bug?
I then checked filters and changed raw water pump. Not been out since to fully test. It has not been overheated excessively only to around 80c + so I hope no damage has been done.
 
You must log in or register to reply here.

Share this page

Top