My wife and I have taken over a 2002, 19’ Larson with a 2004 DF140. Been in the family since new but went to the other side for a few years and hasn’t been cared for and serviced. Sank once. Bad gas cap. Never had a pump impeller replaced. Pisser missing. Tach is not working. Water psi gauge disconnected and plugged due to damaged line. Always been in very clean lake water.
The boat had two problems:
Surging/low rpm’s at full throttle and overheat alarm when trimmed:
Replaced Racor filter and low psi gas filter on engine. Have not looked in or drained VST canister. Several tanks of gas with dry gas and some injector cleaner and the surging has gone away. Engine speed has increased but with no tach, don’t really know the revs. Runs pretty good.
If I block the pisser port at idle with my finger and create about the same hole as the pisser, I get a stream that looks normal. The exhaust outlet on the port side doesn’t flow much at idle but starts flowing at fast idle. At speed, I crawled back there and could hold my hand in the exhaust stream where there was plenty of water. It was almost too hot to cup in your hand. Back at the dock while idling I pulled the cover and I could place my hands on the head area by the plugs but not really hold it on there for long. The top water hose wasn’t too hot to hold on to.
How does this seat-of-the-pants heat check sound? Did not get a high-temp alarm today at speed and trimmed. I found the plastic water-intake screen on the lower unit had a broken post at one of two screws. Wondering if the screen could pull away at speed when trimmed and cavitate and maybe that’s the alarm. Any ideas how to confirm run temperature.
Sorry this is so long and thanks in advance for any help. C.
The boat had two problems:
Surging/low rpm’s at full throttle and overheat alarm when trimmed:
Replaced Racor filter and low psi gas filter on engine. Have not looked in or drained VST canister. Several tanks of gas with dry gas and some injector cleaner and the surging has gone away. Engine speed has increased but with no tach, don’t really know the revs. Runs pretty good.
If I block the pisser port at idle with my finger and create about the same hole as the pisser, I get a stream that looks normal. The exhaust outlet on the port side doesn’t flow much at idle but starts flowing at fast idle. At speed, I crawled back there and could hold my hand in the exhaust stream where there was plenty of water. It was almost too hot to cup in your hand. Back at the dock while idling I pulled the cover and I could place my hands on the head area by the plugs but not really hold it on there for long. The top water hose wasn’t too hot to hold on to.
How does this seat-of-the-pants heat check sound? Did not get a high-temp alarm today at speed and trimmed. I found the plastic water-intake screen on the lower unit had a broken post at one of two screws. Wondering if the screen could pull away at speed when trimmed and cavitate and maybe that’s the alarm. Any ideas how to confirm run temperature.
Sorry this is so long and thanks in advance for any help. C.
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