nigelstgeorge
Well-Known Member
Posted on behalf of my Brother in Law. (Also posted on the Cruising Section but advised to post here instead)
His boat an HR53 is fitted with a Volvo TAMD41HD and based in Langkawi, Malaysia. Major issue with low revs when cruising and black smoke>
In the normal low gear, the turbo kicks in at around 1700rpm and cruising revs are from 1800-2200. In the overdrive gear, the turbo kicks in at around 1450 revs and normal cruising revs are 1500-1700.
If I run the engine in the high overdrive gear, the engine runs fine with no black smoke up to 1250-1300 revs, thereafter the black smoke increases with increasing load. It is not so bad in the normal low gear, but a similar pattern emerges when the engine is under load. In neutral, there is little to no black smoke.
WORK CARRIED OUT
1 Full engine service
2 Fuel tank cleaned out (it was quite dirty)
3 Fuel lines to engine cleaned
4 Racor filters and air filter replaced
5 Fuel float replaced (old one was probably ok)
6 Injectors serviced (no problems reported)
7 Turbo cleaned (it is spinning ok) but I cannot pressure test it in Langkawi.
8 Exhaust elbow riser has some serious corrosion (only 2 years old!) and needs to be replaced but is still functioning ok. There is no sign of eloctrolisis.
9 Prop cleaned thoroughly with no malfunctions/obstructions. Gear mechanism and blades rotating freely. No sign of any prop damage.
THE PROBLEM
The problem is obviously too much fuel and/or not enough air getting in, but there has been no improvement from any of the above actions. From our engine tests in the marina tied up against the pontoon, we have found the following:
1 We cannot get the revs above 1300rpm now in the overdrive gear. With full throttle, the revs start to die and the back smoke and raw soot/fuel is excessive
2 We have however just established that the engine will run smoothly up to 2,400 revs in reverse with no black smoke. So the problem seems to be only in the 2 forward gears which would imply a gear box, prop shaft or prop problem? This test was not done at any previous time.
(PS I have now has 3 risers: the first one which lasted 6 years, 1 which lasted only 18 months and this one which has not been used much but which needs replacing now. I believe this results from a faulty manufacturing batch. We will follow up with Volvo, but we got no satisfaction from them when we tried to replace the last riser under warranty.)
Has anyone got any further suggestions on what the problem may be please and some solutions.
His boat an HR53 is fitted with a Volvo TAMD41HD and based in Langkawi, Malaysia. Major issue with low revs when cruising and black smoke>
In the normal low gear, the turbo kicks in at around 1700rpm and cruising revs are from 1800-2200. In the overdrive gear, the turbo kicks in at around 1450 revs and normal cruising revs are 1500-1700.
If I run the engine in the high overdrive gear, the engine runs fine with no black smoke up to 1250-1300 revs, thereafter the black smoke increases with increasing load. It is not so bad in the normal low gear, but a similar pattern emerges when the engine is under load. In neutral, there is little to no black smoke.
WORK CARRIED OUT
1 Full engine service
2 Fuel tank cleaned out (it was quite dirty)
3 Fuel lines to engine cleaned
4 Racor filters and air filter replaced
5 Fuel float replaced (old one was probably ok)
6 Injectors serviced (no problems reported)
7 Turbo cleaned (it is spinning ok) but I cannot pressure test it in Langkawi.
8 Exhaust elbow riser has some serious corrosion (only 2 years old!) and needs to be replaced but is still functioning ok. There is no sign of eloctrolisis.
9 Prop cleaned thoroughly with no malfunctions/obstructions. Gear mechanism and blades rotating freely. No sign of any prop damage.
THE PROBLEM
The problem is obviously too much fuel and/or not enough air getting in, but there has been no improvement from any of the above actions. From our engine tests in the marina tied up against the pontoon, we have found the following:
1 We cannot get the revs above 1300rpm now in the overdrive gear. With full throttle, the revs start to die and the back smoke and raw soot/fuel is excessive
2 We have however just established that the engine will run smoothly up to 2,400 revs in reverse with no black smoke. So the problem seems to be only in the 2 forward gears which would imply a gear box, prop shaft or prop problem? This test was not done at any previous time.
(PS I have now has 3 risers: the first one which lasted 6 years, 1 which lasted only 18 months and this one which has not been used much but which needs replacing now. I believe this results from a faulty manufacturing batch. We will follow up with Volvo, but we got no satisfaction from them when we tried to replace the last riser under warranty.)
Has anyone got any further suggestions on what the problem may be please and some solutions.
