stevemitchell
Guru
- Joined
- Sep 25, 2018
- Messages
- 542
- Location
- USA
- Vessel Name
- Aruna
- Vessel Make
- Kristen Yachts 50 Pilot House
I posted this over at BoatDiesel.com but after several weeks with no responses, I thought I'd try here.
I have two 1988 TAMD61A Volvo Penta engines with about 4000 hours on each in my Ocean Alexander. There were two owners previous to me, and according to the records I can find, they took very good care of the engines throughout their ownership. The original problematic exhaust elbows were replaced/upgraded, and the original air filters were replaced with an airsep system.
In the last year I have spoken to some other owners of TAMD engines, and to a couple of mechanics who have worked on this and other similar engines both in the US and in Europe.
I have several things I'm trying to determine if they are problems and if I can fix them. Here they are in order of priority:
The rough idle on start is the one that bothers me the most. A mechanic told me it could be from a worn out fuel lift pump. Another told me it's just the way VPs of that vintage start. I can get them to settle down in about 10-15 seconds if I bump the throttles up to around 900 RPM and they sound very nice then. But I think the second problem is related to this one....
Here is a YouTube video I shot of the engines starting up after being cold.
Here is a more recent video after the engines have been running for a minute and stabilized.
I notice quite a bit of what appears to be unburnt fuel on the water. Not sure if that is normal or?
Sometimes even when they're warm, and I have to maneuver around a bit at idle, they start hunting again. I'm thinking this could be something I can adjust with the idle stabilizing screw, but I haven't explored that. I am guessing this could be a good first start.
The amount of smoke at start is a lot, but I have seen some other VPs that are similar. I know using a block heater might help, and I realize this may not be that solvable.
I am curious if it is normal to have a decent amount of smoke when at idle even when the engines are good and hot. It seems like maybe there is unburnt fuel at that point, and the biggest risk/issue is the complaints I have from crew standing near the stern of the boat when docking. I'd love to try to get that fixed too.
General advice I've gotten:
Adjust the idle stabilization screw to stop the hunting at low idle. Seems like the easiest at least for the hunting.
Change the timing from a 61A to 62 to get it to run more smoothly/smoke less. Not really sure about this one - seems like it might cause more problems than its worth, but the person who suggested it has multiple documents and videos showing the success with this method.
Reconnect pre-heaters or add block heaters to cut down on smoke at start. I would really, really not like to reconnect the pre-heaters. I had a scare early on with this boat and the pre-heaters as a result of a faulty key, and their primary purpose is for cold weather starts. Even with them, the smoke was still about the same. Block heaters sound somewhat complicated, and don't sound like they'd eliminate the smoke or reduce it that much.
Other thoughts?
I have two 1988 TAMD61A Volvo Penta engines with about 4000 hours on each in my Ocean Alexander. There were two owners previous to me, and according to the records I can find, they took very good care of the engines throughout their ownership. The original problematic exhaust elbows were replaced/upgraded, and the original air filters were replaced with an airsep system.
In the last year I have spoken to some other owners of TAMD engines, and to a couple of mechanics who have worked on this and other similar engines both in the US and in Europe.
I have several things I'm trying to determine if they are problems and if I can fix them. Here they are in order of priority:
- Rough idle at start
- Sometimes rough idle after being at low RPMs even when warm
- Amount of smoke at start
- Amount of smoke while at low idle even after engines are warm
The rough idle on start is the one that bothers me the most. A mechanic told me it could be from a worn out fuel lift pump. Another told me it's just the way VPs of that vintage start. I can get them to settle down in about 10-15 seconds if I bump the throttles up to around 900 RPM and they sound very nice then. But I think the second problem is related to this one....
Here is a YouTube video I shot of the engines starting up after being cold.
Here is a more recent video after the engines have been running for a minute and stabilized.
I notice quite a bit of what appears to be unburnt fuel on the water. Not sure if that is normal or?
Sometimes even when they're warm, and I have to maneuver around a bit at idle, they start hunting again. I'm thinking this could be something I can adjust with the idle stabilizing screw, but I haven't explored that. I am guessing this could be a good first start.
The amount of smoke at start is a lot, but I have seen some other VPs that are similar. I know using a block heater might help, and I realize this may not be that solvable.
I am curious if it is normal to have a decent amount of smoke when at idle even when the engines are good and hot. It seems like maybe there is unburnt fuel at that point, and the biggest risk/issue is the complaints I have from crew standing near the stern of the boat when docking. I'd love to try to get that fixed too.
General advice I've gotten:
Adjust the idle stabilization screw to stop the hunting at low idle. Seems like the easiest at least for the hunting.
Change the timing from a 61A to 62 to get it to run more smoothly/smoke less. Not really sure about this one - seems like it might cause more problems than its worth, but the person who suggested it has multiple documents and videos showing the success with this method.
Reconnect pre-heaters or add block heaters to cut down on smoke at start. I would really, really not like to reconnect the pre-heaters. I had a scare early on with this boat and the pre-heaters as a result of a faulty key, and their primary purpose is for cold weather starts. Even with them, the smoke was still about the same. Block heaters sound somewhat complicated, and don't sound like they'd eliminate the smoke or reduce it that much.
Other thoughts?