Engine sync at idle ?
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Engine sync at idle ?
Hello Everyone,
So i am having a difficult time this year docking and leaving the dock with my F36. Things get even worse with any kind of wind. I used to drive this boat all over, could dock and control the boat in tight situations etc. 2 years ago I replaced the engines and late last season I replaced the transmissions and v drives.
What I find is happening is that the boat is not turning or responding to the controls as sharply or quickly as before. My thinking on what is happening here is that at idle the motors are not in sync and one is faster then the other. Is it possible to use the engine sync light at idle ? My throttles are stiff so adding any power is very difficult and was never necessary the 4 previous years I had this boat . any help always appreciated.
So i am having a difficult time this year docking and leaving the dock with my F36. Things get even worse with any kind of wind. I used to drive this boat all over, could dock and control the boat in tight situations etc. 2 years ago I replaced the engines and late last season I replaced the transmissions and v drives.
What I find is happening is that the boat is not turning or responding to the controls as sharply or quickly as before. My thinking on what is happening here is that at idle the motors are not in sync and one is faster then the other. Is it possible to use the engine sync light at idle ? My throttles are stiff so adding any power is very difficult and was never necessary the 4 previous years I had this boat . any help always appreciated.
1978 Trojan F36 Tri Cabin
- prowlersfish
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Re: Engine sync at idle ?
I assume the bottom and running gear are clean . If not that's a start . While you could use the engine sync light at idle I would not . trying to sync the engine when docking could be a distraction IMO. While they maybe out of sync like you the idle is slower and maybe on both . I would adjust the idel speed ( and check the mixture adjustment ) and get them both the same . Check it in and out of gear . you may want to set them a liltle higher then spec . Also use a portable tach or photo tach . Dash tachs can be off .
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

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Re: Engine sync at idle ?
The marina does have a ton of grow and sea weed in it this year, worst I have ever seen it.
1978 Trojan F36 Tri Cabin
- prowlersfish
- 2025 Gold Support
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- Joined: Sat Nov 05, 2005 6:56 pm
- Location: Lower Chesapeake Bay ,Va
Re: Engine sync at idle ?
That could be a factor as could be shallow water . BTW Idle speed spec is 650 in neutral But you could try going to 700 to 750 if it helps. again don't use the boats tachs . compare them in gear too .
Edit
Velvet dive limits shifting to 1000 rpm max so your ok at going above the 650 idle spec noted above ( I don't like going above 800 my self )
Edit
Velvet dive limits shifting to 1000 rpm max so your ok at going above the 650 idle spec noted above ( I don't like going above 800 my self )
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

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- Sporadic User
- Posts: 92
- Joined: Wed Dec 05, 2012 6:26 pm
- Location: Windsor, Ontario Canada
Re: Engine sync at idle ?
Thanks for the info, I am going to grab a portable tach today and check it out. I will report back my findings.
1978 Trojan F36 Tri Cabin
Re: Engine sync at idle ?
Milfoil often grows more on one side (sunny side and a shady side) and I know of a boat that really dragged its gear on ONE side while trying to back out. The owner couldn't get while he was getting stuck. It happens.
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- Joined: Wed Dec 05, 2012 6:26 pm
- Location: Windsor, Ontario Canada
Re: Engine sync at idle ?
So one motor was running pretty low rpm at idle it actually died on me coming back in on Saturday which was quite interesting and basically my biggest fear. lol
I guess the points were down in the rotor or something, and I once again have junk in my fuel. got some of that corrected and seems to be a lot better.
Now this brings up another question. Anyone ever change the ignition systems on these engines or even get rid of carbs ? Seems to be were all my problems are last few years
I guess the points were down in the rotor or something, and I once again have junk in my fuel. got some of that corrected and seems to be a lot better.
Now this brings up another question. Anyone ever change the ignition systems on these engines or even get rid of carbs ? Seems to be were all my problems are last few years
1978 Trojan F36 Tri Cabin
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- Location: Panama City Beach
Re: Engine sync at idle ?
My tri cabin has electronic ignition and I replaced the carbs with Edelbrock 1409 carbs. The previous owner replaced the distributor on the starboard engine with a Mallory electronic marine unit. The port engine is a Chrysler electronic distributor.
Throttle body injection for marine applications and I have heard that it works well, however it is a little pricy.
Throttle body injection for marine applications and I have heard that it works well, however it is a little pricy.
1985 Mako 258 (One Owner)
1981 Trojan Tri Cabin
George
1981 Trojan Tri Cabin
George
- prowlersfish
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Re: Engine sync at idle ?
I have yet to see a aftermarket EFI run right on a marine engine . Seen it done and they all end up going back to a carb .
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

Re: Engine sync at idle ?
+1prowlersfish wrote:I have yet to see a aftermarket EFI run right on a marine engine . Seen it done and they all end up going back to a carb .
If anybody finds one, let me know!
She was a 1969 36 ft wooden beauty with big blue 440s that we'll miss forever.
And thanks to the gang, 2012 Trojan Boater Of The Year
And thanks to the gang, 2012 Trojan Boater Of The Year
Re: Engine sync at idle ?
Great discussion on the engines and sync. But back to the docking. Honestly, when I come up to our slip and get into the approximate position, I let go of the steering wheel. I dock it with just the engines. Our slip is in a slower current river, and you always have current to work with (wind and current are your friends I tell my kids when teaching them to dock). I just bump each drive into and out of gear to steer the boat into the slip using each engine to move where I need to. Keep the rudder straight, let the engines do the rest. This takes the sync issue out of the equation.
Yes, I have used the rudder on few occaisions to "slide" into a particular docking situation, but rarely touch the wheel. This assuming you have twin screws.
Btw... Kids fight over who gets to dock the boat......
Yes, I have used the rudder on few occaisions to "slide" into a particular docking situation, but rarely touch the wheel. This assuming you have twin screws.
Btw... Kids fight over who gets to dock the boat......
1988 Trojan 11 Meter Express
My wife made me do it... Really.....
My wife made me do it... Really.....