"So that engine gradually lost rpm and the sync age was making up fuel to match the rpm's."
THat would have happened regardless of "who" was managing power. ANd in the end, the power manager is the governor...not the synchronizer. The syncro sets the spring tension on the governor just like you did via the power lever.
"Your tachs tell you nothing about the load on the engines - the most important thing you can know.
Any variation in props as tuned, growth on the props or anything you pick up along the way will unbalance the load between the engines.
The engine which becomes overloaded will be subject to damage much sooner then you might think."
You proved my point. Boost/pyro gauges are reference gauges to determine what is going on with the engine...not a gauge to set power to. I have boost/pyro gauges on my current boat and I will have them on the new one. I am a huge fan. I just don't set power by reference to them. I look at them to make sure everything is copacetic. If not, then investigate further.
"You cannot set power with a tach especially on a twin engine application - if you have ever down that you likely know from the unbalanced fuel usage."
I always set power by tachs. And I am willing to bet 99% of people on here do. I think you are a pilot, right? Think about "primary" instruments versus seconday. When you are powering up in a planing boat, the absolute number one gauges you are looking at is tachs....and I guess that would ring true in any boat...twin engine or otherwise. Hell when I am powering up the jet I fly, the N1 gauges are the primary instrument when bringing the engines up for takeoff....and THEN look at other instruments to make sure everything is ok.
Nothing wrong with fine tuning with references to other instruments. But in the end, this thread is about WAH WAH WAH WAH WAAAAH WAAAAH WAAAAAAAAH WAAAAAAAAH WAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHH.
That last letter grouping is what I am looking for.
The tachs are not accurate. I dont sync to the tachs...I sync it by ear....wah wah wah waaaaaaaaaaaaahhhhhh. Well aware of Aetna digital tachs as I have them on my current boat. Likely the first mod I will do on this boat. I will have to redo my panel though as the tachs are huge on this boat so I would need something to fill that hole. Anyway, maybe digital tachs and some tension adjustment might be all I need.
I always set power by tachs. And I am willing to bet 99% of people on here do. I think you are a pilot, right? Think about "primary" instruments versus seconday. When you are powering up in a planing boat, the absolute number one gauges you are looking at is tachs....and I guess that would ring true in any boat...twin engine or otherwise.
I expected to look at Glendinnings when we bought our boat, but... the original analog tachs weren't great and I replaced those with Aetna tachs... before I got around to thinking more about syncs... and it turned out the digital tachs have been sufficient.
CruzPro also makes digital tachs, smaller 2" format. Happens I've also replaced all the other engine gauges with CP models, but that was after changing the tachs... and the 4" Aetnas fit my existing holes with no mods.
If your existing holes are larger than a 4", you could maybe just make up a custom bezel for a short-term fix... and maybe (or not) do a complete rework at your leisure?
-Chris
I expected to look at Glendinnings when we bought our boat, but... the original analog tachs weren't great and I replaced those with Aetna tachs... before I got around to thinking more about syncs... and it turned out the digital tachs have been sufficient.
CruzPro also makes digital tachs, smaller 2" format. Happens I've also replaced all the other engine gauges with CP models, but that was after changing the tachs... and the 4" Aetnas fit my existing holes with no mods.
If your existing holes are larger than a 4", you could maybe just make up a custom bezel for a short-term fix... and maybe (or not) do a complete rework at your leisure?
-Chris
"So that engine gradually lost rpm and the sync age was making up fuel to match the rpm's."
THat would have happened regardless of "who" was managing power. ANd in the end, the power manager is the governor...not the synchronizer. The syncro sets the spring tension on the governor just like you did via the power lever.
"Your tachs tell you nothing about the load on the engines - the most important thing you can know.
Any variation in props as tuned, growth on the props or anything you pick up along the way will unbalance the load between the engines.
The engine which becomes overloaded will be subject to damage much sooner then you might think."
You proved my point. Boost/pyro gauges are reference gauges to determine what is going on with the engine...not a gauge to set power to. I have boost/pyro gauges on my current boat and I will have them on the new one. I am a huge fan. I just don't set power by reference to them. I look at them to make sure everything is copacetic. If not, then investigate further.
"You cannot set power with a tach especially on a twin engine application - if you have ever down that you likely know from the unbalanced fuel usage."
I always set power by tachs. And I am willing to bet 99% of people on here do. I think you are a pilot, right? Think about "primary" instruments versus seconday. When you are powering up in a planing boat, the absolute number one gauges you are looking at is tachs....and I guess that would ring true in any boat...twin engine or otherwise. Hell when I am powering up the jet I fly, the N1 gauges are the primary instrument when bringing the engines up for takeoff....and THEN look at other instruments to make sure everything is ok.
Nothing wrong with fine tuning with references to other instruments. But in the end, this thread is about WAH WAH WAH WAH WAAAAH WAAAAH WAAAAAAAAH WAAAAAAAAH WAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHH.
That last letter grouping is what I am looking for.
"I always set power by tachs. And I am willing to bet 99% of people on here do. I think you are a pilot, right?"
I am not a pilot - and I think yo are correct that most people set there engines by tach and that is how some get into trouble. If your props are close your rpm will likely be close as well but not exact.
"Nothing wrong with fine tuning with references to other instruments. But in the end, this thread is about WAH WAH WAH WAH WAAAAH WAAAAH WAAAAAAAAH WAAAAAAAAH WAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHH.
That last letter grouping is what I am looking for."
The boats we have do not generate any sort of annoying sound whether the rpm is synced or not - engine room insulation along with exhaust mufflers always left us with the ability for normal conversation on the bridge or pilothouse. Wind noise was the predominant issue dependent upon weather.
The boats we have do not generate any sort of annoying sound whether the rpm is synced or not - engine room insulation along with exhaust mufflers always left us with the ability for normal conversation on the bridge or pilothouse. Wind noise was the predominant issue dependent upon weather.
DITTO!I can't hear worth a darn. But I can sure hear twin diesels that are out of sync when at the helm or especially at the stern. Not all of us are concerned about odd engine vibes, but it drives me nuts.
The boats we have do not generate any sort of annoying sound whether the rpm is synced or not - engine room insulation along with exhaust mufflers always left us with the ability for normal conversation on the bridge or pilothouse. Wind noise was the predominant issue dependent upon weather.
This whole time you have been driving your guests crazy...hahaha!!! Just kidding. And it doesn't take a loud boat to notice. I think one of the reasons it is difficult on this boat is that it is so quiet. But I can still hear it. My current/old boat and new boat are both very quiet boats. I run on plane so the most noise is generated by the boat moving through the water. Engine noise is minimal to almost non existent. But it is the harmonic vibraton that causes the WAH WAH. Meridian has underwater exhaust(which I do not like). So engine noise is muffled even further.
Our boat has a Glendinning synchronizer. A while back it began malfunctionaling. One engine would periodically drop 200 RPM and then come back up. It drove me crazy so I stopped using it. Instead, I use the tachs to match RPM. I had been using the alternator as a signal generator to run my replacement pprogrammable tachs which worked quite well (but not perfect) as to accuracy. Knowing true RPM via a phototac, I was able to synchronize quite well.
Cummins uses a magnetic pickup that counts teeth on the flywheel. SO while not exactly a phototach, it is every bit as accurate. When hooked up to a digital tach, it is absolutely 100% accurate.