technical stuff

[fish 4 life]

Re: technical stuff

How far in will it trim ???? (photo of that would help) if possible

What do you mean by how far in will it trim? Are you talking about down trim? The picture is of the motor all the way down.

 

[kenmyfam]

Re: technical stuff

What do you mean by how far in will it trim? Are you talking about down trim? The picture is of the motor all the way down.

Where do you have the trim when you try the hole shot ???
Up ?? middle ?? down ??

 

[fish 4 life]

Re: technical stuff

Where do you have the trim when you try the hole shot ???
Up ?? middle ?? down ??

I have tried having the trim in the down, middle, and up position when trying the hole shot.

 

[kenmyfam]

Re: technical stuff

I have tried having the trim in the down, middle, and up position when trying the hole shot.

Is there any noticeable difference between full up and full down ???

 

[fish 4 life]

Re: technical stuff

Is there any noticeable difference between full up and full down ???

No. When trimmed in full up or full down, it still acts the same. The bow just sits way up high and the RPMs stay at around 2500, and the boat goes about 15 mph.

 

[kenmyfam]

Re: technical stuff

Have you weighed everything and compared to original specifications ???
Can you borrow a 15" pitch prop to try ???

 

[fish 4 life]

Re: technical stuff

Have you weighed everything and compared to original specifications ???
Can you borrow a 15" pitch prop to try ???

What do you mean by, weighed everything? Are you talking about weighing the whole boat itself.

I don't know where I can get any 15" pitch props, besides down at the prop shop.

I talked to Ranger boats today and they said I probably need a transom wedge. They said they have had to put transom wedges on older outboards in the past.

They also suggested drilling ventilation holes in the prop.

 

[emdsapmgr]

Re: technical stuff

Possible the engine is only firing on 3 cyls. Try checking spark with an inductive timing light the next time you are trying to get the boat on plane. Check each plugwire for nofires or misfires. You can see it in the flashes from the light.

 

[kenmyfam]

Re: technical stuff

What do you mean by, weighed everything? Are you talking about weighing the whole boat itself.

I don't know where I can get any 15" pitch props, besides down at the prop shop.

I talked to Ranger boats today and they said I probably need a transom wedge. They said they have had to put transom wedges on older outboards in the past.

They also suggested drilling ventilation holes in the prop.

I was thinking in the same direction as the transom wedges with my earlier questions about the trim.
Prop shop may lend you one on test as long as you have the courtesy to buy one from them when you find the perfect prop.
The weight thing is to make sure you are not laden with water soaked foam. Take the outfit to your local scales with everything out except the motor and weigh it. Go launch boat and tie up. Come back and weigh trailer. You can get the motor weight by looking it up...so
Weight of entire outfit minus weight of motor minus weight of trailer = weight of your boat.
Find the dry weight out from Ranger and see how close you are.

 

[fish 4 life]

Re: technical stuff

Possible the engine is only firing on 3 cyls. Try checking spark with an inductive timing light the next time you are trying to get the boat on plane. Check each plugwire for nofires or misfires. You can see it in the flashes from the light.

I had the engine inspected and put on a dyno by a mechanic and he says the engine runs like a top. Like I said, once I can get the engine on plane, the boat will do 45+ mph. I don't think the boat would be able to go this fast on only 3 cylinders.

 

[fish 4 life]

Re: technical stuff

I was thinking in the same direction as the transom wedges with my earlier questions about the trim.
Prop shop may lend you one on test as long as you have the courtesy to buy one from them when you find the perfect prop.
The weight thing is to make sure you are not laden with water soaked foam. Take the outfit to your local scales with everything out except the motor and weigh it. Go launch boat and tie up. Come back and weigh trailer. You can get the motor weight by looking it up...so
Weight of entire outfit minus weight of motor minus weight of trailer = weight of your boat.
Find the dry weight out from Ranger and see how close you are.

I had some holes drilled to test for water in the foam and no water was found. The motor weighs about 300 lbs.

 

[wilde1j]

Re: technical stuff

It certainly looks like time to borrow a 15" pitch prop and be prepared to buy it from the prop shop if it works. Not a big deal. You haven't said what RPM your motor is turning @ WOT ... if it's below 5800 RPM, that would confirm whether a lower pitch prop makes sense.

 

[kenmyfam]

Re: technical stuff

I had some holes drilled to test for water in the foam and no water was found. The motor weighs about 300 lbs.

Drilling holes is one thing, actually verifying it by weighing it is the only way to be 100% sure in my opinion.

 

[Silvertip]

Re: technical stuff

Definitions (brief) on what you were told to do/check:

Link & Sync the carbs: You don't link & sync the carbs. You synchronize throttle opening with spark advance. If you have to have this explained as to what this means, you likely do not understand the mechanics involved and therefore this is best left to a shop. The process is long and not something covered on this forum. In my shop manuals it is typically 6- 12 pages long.

Check carb opening: This also is part of link&sync but you can "check" this. You remove the air box on the carbs so you can see the throttle plates inside the throat of the carb. With the engine OFF, move the throttle full open. At that setting the butterflies in each carb throat should be fully open (90 degrees to the carb throat. No more, no less.). Try to adjust this and you will likely screw up link&sync so don't do this without a service manual or competent help.

Pickup timing is correct: As you move the throttle from idle to increase speed, the throttle linkage begins to advance ignition timing in a specific relation to the amount of throttle opening. The exact point at which that begins to happen is pickup timing. Again -- part of link&sync.

Check timer base: As you move the throttle, the ignition timing advances accordingly. You can see the timer base moving under the flywheel as this happens. If it doesn't go all the way to the full throttle stop screw, it is either sticking or -- you guessed it, link&sync is screwed up.

Max timing advance: Ignition timing advances to a preset maximum as throttle reaches wide open. If it advances too far you risk engine destruction. If it doesn't advance far enough the engine performs poorly. Yes -- part of link&sync.

Link & sync as I mentioned is a long procedure that must be done in a specific sequence or the entire effort is worthless and may cause engine damage.

 

[fish 4 life]

Re: technical stuff

I went to the local prop shop and I talked to him about going down in pitch on a prop. He looked at my boat and he said the engine is too low and needs to be raised about an 1 or 1 1/2 inch. I told him I thought it was to high because the anti-cavitation plate was about 3 inches higher than the bottom of the boat. He said that not as big a deal as the prop being about 5 inches below the boat. He said the center of the prop should be no more than 4 inches below the boat and 3 inches for a four blade prop. He said the reason for my excessive bow rise is because the motor is too deep or too low.

 

[reeldutch]

Re: technical stuff

great to hear your problem is solved.
so you gonna move it up 2 inches and get a 4 blader?


is this boat new to you ?

 

[fish 4 life]

Re: technical stuff

great to hear your problem is solved.
so you gonna move it up 2 inches and get a 4 blader?


is this boat new to you ?

I would not say my problem is solved yet. I tried a four blade 13 X 17 SS prop. It did not seem to help much. The prop did seems to help the boat handle better when it was on plane.

The boat is not new, but the motor is. I use to have a 1985 Mercury 125 HP and the motor went bad, so I got this 1978 Evinrude 140 HP. Something has got to be different with this motor. I don't know if the motor is higher or lower or is just heavier or what.

 

[wilde1j]

Re: technical stuff

If the AV plate is under water at WOT, the motor's too deep ... move it higher until the AV plate is not covered at all. Then mess with prop pitch.

 

[kenmyfam]

Re: technical stuff

Same length shaft as the old motor ???

 

[fish 4 life]

Re: technical stuff

Same length shaft as the old motor ???

not sure.