I recently bought a RIB with a 2008 Suzuki DF200 V6. The engine had not been run for well over a year and I have had a lot of trouble getting it running properly.
The main issue is that it will not rev out properly under load. It generally struggles to get beyond 2,000–3,000 rpm, and when I pull the throttle back to idle it often dies.
It also needs a lot of throttle to start. Once it starts, I have to hold the revs up for a while before it will stay running, and even then it may cut out again when returned to idle.
Initially, I suspected fuel starvation because it kept dying above roughly 2,000 rpm. So far I have:
I tested it as much as possible out of the water and it appeared to rev up without any obvious problem. However, once launched and under load, it was initially stuck at around 2,100 rpm.
Strangely, turning the boat in circles causes the revs to rise. When straightened up again, it mostly held the higher revs, but it would still not properly rev out and there was very little increase in speed. Maximum speed was around 16 knots.
There were no warning lights, buzzers or fault indications.
So the main symptoms are:
Any advice on what tests I should do next would be greatly appreciated.
The main issue is that it will not rev out properly under load. It generally struggles to get beyond 2,000–3,000 rpm, and when I pull the throttle back to idle it often dies.
It also needs a lot of throttle to start. Once it starts, I have to hold the revs up for a while before it will stay running, and even then it may cut out again when returned to idle.
Initially, I suspected fuel starvation because it kept dying above roughly 2,000 rpm. So far I have:
- Completely drained and refilled the fuel tank
- Replaced all fuel filters
- Cleaned the VST
- Fitted a new water separator
- Replaced the fuel lines
- Replaced the spark plugs
- Fitted four new injectors
I tested it as much as possible out of the water and it appeared to rev up without any obvious problem. However, once launched and under load, it was initially stuck at around 2,100 rpm.
Strangely, turning the boat in circles causes the revs to rise. When straightened up again, it mostly held the higher revs, but it would still not properly rev out and there was very little increase in speed. Maximum speed was around 16 knots.
There were no warning lights, buzzers or fault indications.
So the main symptoms are:
- Needs a lot of throttle to start
- Dies when the throttle is returned to idle
- Will not rev properly under load, usually only reaching around 2,000–3,000 rpm
- Turning in circles sometimes allows the revs to increase
- Very poor speed even when the revs rise
Any advice on what tests I should do next would be greatly appreciated.