Sluggish start then things are fine. Why?

[yanco]

When I start a day of boating, each time I begin - my engine only gets up to about 3900 rpms at full throttle - not even enough to get up on plane. Then - after about 5-10 minutes at full throttle(it varies each time) it kicks in and gives me the full 135hp and about 5000 rpms.<br />For the rest of my boating day I can immediately jump back up to the full rpms at full throttle but why does this happen consistently to me in the beginning? I do give sufficient warm up time in neutral (5-10 min)before trying to get up on plane. I have checked the compression and have replace all of the fuel filters/water seperating filters and fuel line.

 

[The Marine Doctor]

Re: Sluggish start then things are fine. Why?

While this problem is still happening...turn off the engine...then pull the plugs. We are looking for a wet plug...or one that does not seem to have fuel being delivered to it.<br /><br />Then get back to us.<br /><br />TMD

 

[yanco]

Re: Sluggish start then things are fine. Why?

Well, I may have found the problem. I took my timing light and hooked it up to each plug wire. 2 were not firing. I then hooked up the light to the incoming lead to the coil and they were both firing but still the high voltage was not. I think that I may have a couple burnt coils. I will advise.

 

[The Marine Doctor]

Re: Sluggish start then things are fine. Why?

It not likely that the coils are the problem...I would maybe suspect the Trigger or PowerPack.<br /><br />3 sides to the trigger...each side controls spark for 2 cyls.<br /><br />If part of the trigger dies...so do 2 cyl's.<br /><br />Powerpack will do the same thing.<br /><br />TMD

 

[yanco]

Re: Sluggish start then things are fine. Why?

But I have spark going into the coils but not out of them. If the trigger or powerpack was the problem, wouldn't there be no incoming spark to the coils?

 

[The Marine Doctor]

Re: Sluggish start then things are fine. Why?

Swap the coils around from known working ones. See if the problem follows.<br /><br />TMD

 

[yanco]

Re: Sluggish start then things are fine. Why?

I went down to the boat store and bought two new coils. Now the motor click starts when cold and all cylinders have spark going to the plug. I gained 150 idle rpm. I haven't water tested it yet but it hasn't click started in a long time. I will let you know tomm. Thanks a million for your help.

 

[yanco]

Re: Sluggish start then things are fine. Why?

Fixed it. Works great. Guys, thanks for all your help. Motor has not ran this good since I owned the boat.