Hi all...
I have a 1987 17' Larson with a 110hp V4 Evinrude outboard. Up until now it's been a great running boat.
This season it has developed a knocking or hammering condition.
I can run it in neutral at low thru high speed just fine. Also, I can water test it in the driveway at idle or in gear (Prop turning) just fine.
Here's the problem, when I'm on the lake, if I go faster than no wake speed, it starts to "knock or hammer" at regular intervals. The intervals get shorter the faster I go.
When it "knocks", it's like I hit a rock with the prop, the whole motor shakes, just once... until the next interval. At the highest speed, it's about once every 8 seconds, at medium speed, about every 15 seconds, but at no-wake speed, it's just fine, no knocking...
Any ideas? I'm thinking it's not the engine, but something in the gears?
thanks,
Mike
I have a 1987 17' Larson with a 110hp V4 Evinrude outboard. Up until now it's been a great running boat.
This season it has developed a knocking or hammering condition.
I can run it in neutral at low thru high speed just fine. Also, I can water test it in the driveway at idle or in gear (Prop turning) just fine.
Here's the problem, when I'm on the lake, if I go faster than no wake speed, it starts to "knock or hammer" at regular intervals. The intervals get shorter the faster I go.
When it "knocks", it's like I hit a rock with the prop, the whole motor shakes, just once... until the next interval. At the highest speed, it's about once every 8 seconds, at medium speed, about every 15 seconds, but at no-wake speed, it's just fine, no knocking...
Any ideas? I'm thinking it's not the engine, but something in the gears?
thanks,
Mike