No holeshot

[Darrenkmac]

Hi everyone. I have a 94 model 174 Evinrude that is pushing a 92 Ranger 481 V. It cranks and revs up fine with no problem idling. When I take off, it moves forward and slowly builds up speed until it finally reaches plane and then the boat takes off like a rocket. I have no problem with top end it seems. This problem has progressed from the spring into the summer and seems to be getting worse. This past Saturday it took over 100 yards to finally come on plane. I had changed the bulb, thinking that it may have been the problem but with no results. I have a Hot Foot and I have looked at the linkages and they seem ok. my controls appear to be ok. I am running a digital powerpack and this motor ran very well in the past. I had no problem pulling a tube with the boat. My prop is a 24 pitch Raker and I have not changed props recently. I was wondering if my VRO may be weakening perhaps. It still uses oil from the oil tank so I know that both oil and fuel are still mixing. I don't have a lot of white smoke either. The motor seems to be winding up slowly so to speak as my speed increases going up to plane, then it is like something kicks in. I am flooring the Hot Foot to get it up to plane and then I have to back off as it takes off to keep from over reving it seems. Any ideas are appreciated. Thanks, Darren

 

[mrcj001]

Try some Smart Trim Tabs......they worked for me.

http://nauticusinc.com/

 

[flyingscott]

Are you running a jack plate? What prop are you running and what are your wot rpms. Also need the model # of your motor.

 

[Darrenkmac]

Thanks for responding mrcj001 and flyingscott. I am indeed running a jackplate. My prop is a 14x24 Raker. The motor is 175 Fastrike 1994 with a digital powerpack. when I need the speed, I can push my 19 foot Ranger as much as 65 mph. I built this engine myself in my garage out of neccesity almost 9 years ago. It had plenty of power up until about 6 months ago where I noticed that it was taking longer to get up on plane. my problem has slowly gotten worse. My motor is basically a Johnrude. It has a 150 Ficht lower that the 150 Ficht powerhead was removed from. A 175 Fastrike powerhead with carbs was put in its place with some mounting modifications and this motor has been a powerhouse for about 8 years, until my holeshot went away. Believe me, I know that setup seems nuts, but it is a way to salvage a blown Ficht from their early years. I can certainly build the engine, but I am not good at diagnosing the symptoms and I appreciate any advise on what may be wrong with it. I mentioned the VRO in my original post because it makes sense that the carbs are not getting the right fuel or maybe some air leaking into the fuel system somewhere ? The fact that it eventually takes off like a rocket really confuses me. I am hoping that someone has seen this before out of a carbed engine. Thanks again, Darren

 

[175se]

Is it making temprature? If not its not going to use the fuel properly on the low end.

 

[flyingscott]

It could be a fuel issue. I would look to make sure the impulse line to the pump is not ruptured or has a hole in it. I would also test for fuel pressure.

 

[oldboat1]

^^think that makes sense.

​Curious -- Is that stainless Raker prop vented?

 

[Tim Frank]

Is this boat trailered or kept in the water. Might be waterlogged hull.

 

[Darrenkmac]

The boat stays inside of my taxidermy shop on a carpeted display floor so it stays out of the weather or the water unless it is being used. Shouldn't be waterlogged. The Raker prop is indeed vented with three vent holes in front of the blades. As far as " is it making temperature" ? I don't know if it is or not. Last Saturday the water temp at the lake was in the mid 80s. I have not checked the thermostats. Flyingscott mentioned that it may be a fuel issue. I am going to look into this possibility very hard. I do have a fuel pressure gauge and I am curious to see if my line will hold the pressure. I may need to replace the lines pertaining to the pump. I will also check the cone filter in the pump. I have an " ethanol" in-line filter that I will change as well and see if that helps. My top end wot is about 5800 rpm. when I am taking off from dead still however it is much lower. I can floor the pedal with the engine tucked and my wot rpms start slow and gradually increase slowly but smoothly. I may move forward from 50 to 100 yards like this as the boat slowly builds speed and comes up on plane. At about 3/4 up to plane my boat revs up to full rpms and the boat takes off like a bullet. It is then that I back off of the pedal to keep from over reving or blowing out the prop so to speak. Up until recently I had great holeshot and could pull up a skier if I wanted to. I hope this info helps. Sorry for the delay on responding, I had to go to my shop to check the prop to see if it was vented before responding. Thanks, Darren

 

[fhhuber]

* No purposeful changes to the boat, but boat performance changing. *

That means something changed about how the engine is performing. (or the boat got heavy)

How long since the engine has had a "tune up"?
Pull a spark plug and look at it. Compare to one of the many charts for diagnosing an engine based on the spark plug.
Start there.

Something is keeping you from having normal power in your lower rpm range.

It does not sound like a spun prop hub, but check for that anyway by painting a line across the hub (side to side and across the prop nut) and seeing if the pieces of the painted line shift in relation to each other. Just get it up on plane, then stop the engine and raise the prop so you can see the line. Its another cheap and easy thing to look at.

 

[jakedaawg]

Compression test.

Spark check at idle,

Probably clean the little holes in the throttle bodies as this is the idle and transition circuits.

Check that lid of VST is not leaking.

 

[Darrenkmac]

Thank you for all of your help. It has been a while since I posted a reply and I have tried several different things to see if they would help. I changed the spin on fuel filter and cleaned out the cone filter entering the power head. ( It was not dirty). I tried upping the fuel grade to a higher octane. Checked the linkages. Changed the fuel bulb and the line all the way back to the tank. And of course new spark plugs. I even looked at changing the fuel pump. I have not changed it yet though because It has absolutely no issues at mid range or WOT. I had it on the water yesterday in a bass tournament. The motor worked flawlessly when I blasted off. When I sat down after fishing and cranked up again, it stalled and I had to crank it up several times and even re pump the bulb because it had gotten soft. It then slowly moved forward for about 150 yards before it just took off like nothing was wrong. This went on all day like this. It would slowly and I mean very slowly build rpms until it finally would take off like a rocket. If I tried to take off quickly it would go dead. I could gradually push my hot foot throttle and it would go forward and as I would pick up speed, I would have the pedal eventually to the floor. Once it got on plane I would back off on the pedal to keep from over reving the motor. A friend suggested that one of the slow speed jets was stopped up. I am wanting to try and fix it myself but I may end up having to put it in a shop somewhere. Any suggestions are appreciated. Thank you

 

[Faztbullet]

How did you use the front air silencer with Ficht cowl? Anyway check the carbs for the high speed jets being loose.

 

[TN-25]

Besides what others mentioned, I would verify the timing. Lazy acceleration can be a result of the timing being off. So I guess that re-iterates what was said earlier about when the last time it was tuned up.

 

[jimmbo]

You say you removed a 150 FICHT powerhead, and dropped a 175 carb powerhead on with some “mounting modifications “. First of all, the exhaust tuner is different between the two, however, you say the engine ran okay. Any chance one of the gaskets in the modified mounting has slipped or burnt thru and is affecting the separation of the two exhaust systems?(6 cylinder 2 strokes, are treated as two 3 cylinder engines when it comes to exhaust systems and tuning). I had a gasket failure on a Merc inline6 that created essentially a balance tube between the two systems. It did wreck havoc with the torque curve of the engine and its acceleration.

 

[Faztbullet]

60 degree tuners are the same.......

 

[Darrenkmac]

Faztbullet, Thank you for responding. I had actually gone to a boat salvage yard nearby and traded my Ficht cowling for an Intruder Cowling and everything worked out fine. I ordered some new decals as well. I may go through carbs again and see if that will help. I have tried to research my issue and I have found a number of people saying it is my powerpack. Sometimes my boat takes off properly. Most of the time though it struggles on takeoff. it ran great for almost 9 years.

 

[Darrenkmac]

Jimmbo, Thank you for responding. I built this engine almost nine years ago and if I remember correctly, the exhaust and the mounting bolt size as well as the drive shaft length had to be modified. It ran great for almost nine years. This motor takes off properly sometimes but mostly it struggles on takeoff. Last Saturday my first run up the lake was flawless. I ran about 3/4 of a mile and fished for about 15 minutes. when I cranked up again, I had to re-crank as many as 3 times. The fuel bulb was limp. pumping it up allowed me to stay cranked, but I putted forward for about 100 yards before it came up on plane. It then ran awesome. Until I stopped again and restarted about an hour later. This went on all day with an occasional Flawless takeoff. I have read anything from jets dirty to a bad powerpack. I repair CNC machines as a technician in a factory and I hate when I come across problems that really stump me. I am highly trained on those machines, but not as much on my own boat motor. I am grateful for the input from this forum. I would love to fix this issue myself if possible.