1986 Evinrude 110hp V4 Prop Help

[Relaxed427]

Hey guys and gals. I recently dinged up my old aluminum prop in a lake earlier this week. Turns out the lake was considerably lower then usual. In any case- I am looking to get a new prop to replace this.

Right now I have this data-
Boat- 1986 Ebbtide Dyna-Trak 180 ss
Engine- 1986 Evinrude 110 V4
Prop- 13in x 19pitch 3 Blade Aluminum
Top Speed GPS- 38mph
RPM at WOT- 4700rpm

Data I am finding I need-
Gear ratio, slip, manufacturer's suggested WOT RPM.

I am ok with the boats top speed(more is always better though), however the hole shot is a little less then I would like. I don't know for sure, or where to find this info, but it seems the engine may be under propped.

I am thinking I need to make the jump up to a 4 blade propeller with a slight higher pitch. Something like a 4 blade, 13-1/4" dia, 21" pitch like this:

http://boatpropellers.iboats.com/Ev...34180/?**********=738255741&*******=706338965

Any help is greatly appreciated, and sorry for having to ask you all these basic questions, I just can't seem to find that other info.

Thanks!

 

[Gary H NC]

Re: 1986 Evinrude 110hp V4 Prop Help

4700 rpms is lugging that motor. It should turn at least 5500 at WOT.
Increasing pitch is only going to make it worse and the hole shot will be worse too..
See if any local marinas will let you test a 15 and 17 pitch.

 

[hwsiii]

Re: 1986 Evinrude 110hp V4 Prop Help

Relaxed, what I was able to find out about your motor was that it should turn between 4,500 and 5,500 RPM at WOT, the gear ratio is 2 to 1 and you are using too high a pitch prop right now with the prop you have. Please verify the information about your motor from a third party. You should change it to a 17" pitch prop in the same manufacturer and model you have at this time. That will bring your RPM up to right at 5,100 RPM and your speed should stay very near the same. But your hole shot and acceleration will increase very well. Here are the figures for that change. Your slip will stay about the same at 10%.

H

 

[Gary H NC]

Re: 1986 Evinrude 110hp V4 Prop Help

5800 rpms is the sweet spot with those motors...

 

[Tacklewasher]

Re: 1986 Evinrude 110hp V4 Prop Help

5800 rpms is the sweet spot with those motors...

Agreed. Manufacturer states 4500-5500 but they like 5500-6000 with modern gas. Others here with more posts than I have have been saying this for years and they know what they are talking about.

I run a 15p SS on my 1980 115 on an 18' Starcraft and am about 5800 and almost 40 mph. If I run my 17p Alum I lose RPM but keep the speed. I'm using the alum for running in rivers and such and the SS for summer boating.

 

[Relaxed427]

Re: 1986 Evinrude 110hp V4 Prop Help

Thank you all very much!

I was thinking about the RPM at WOT figure, and I guess I have a question.

I am basing my RPM on the guage on my console. Is there a way to double check that figure?

This makes me wonder if my numbers are off for a different reason, since it seems to be very far off. Are the numbers I am getting expected with this prop and motor/hull combo?

If my numbers are good, and that factor would not affect the numbers, I will definately be getting a different prop closer to the ideal you have recommended.

Thanks again all of you!

P.S. If anyone read this and saw the part about the throttle body- I just checked, and it is the throttle on the engine that is topped out. So not an issue.

 

[hwsiii]

Re: 1986 Evinrude 110hp V4 Prop Help

Tacklewasher, I am sorry I don't seem to understand what adavantage you have gained by running that motor at higher RPM. You are getting the same speed with both props, except that with the 15" pitch prop you are turning more RPM than the manufacturer recommends and theoretically using more fuel in the process and wearing the motor out quicker because you are turning more RPM in the same amount of time at the same water speed. I can do that with any motor, just run too small a pitch prop, so I dont understand where the difference is in this motor and other postings I have seen posted on here that say about the same thing.
I will be the first to say that I don't know everything I would like to know about motors, but what is the advantage of doing this. You are not gaining any speed, the motor wears out quicker, you are probably using more fuel and theoretically this can be done with any motor.
This is something that I would like to really understand, as it doesn't agree with my knowledge of motors and prop theory. I am NOT saying you are wrong, but I would like to understand the reasoning so that I have a better understanding and can increase my knowledge base.

H

 

[72SideWinderSS]

Re: 1986 Evinrude 110hp V4 Prop Help

A real world experience:

1979 J/E 115 fresh rebuild, 16ft sidewinder, propped for 5000 rpm, 110hrs total, coked up and swallowed a ring.

Same motor fresh rebuild, same boat, propped for 5800 rpm, tore down @ 100 hrs, very little coking if any.

Dhadley can attest to this scenario many times over.

 

[72SideWinderSS]

Re: 1986 Evinrude 110hp V4 Prop Help

Relaxed,
where is your A/V plate in comparison to the bottom of your hull?
I would first work the setup, before changing to a different prop.

 

[Gary H NC]

Re: 1986 Evinrude 110hp V4 Prop Help

Raise the motor up a hole or two and see if you gain any speed and rpms.

When i bought my Johnson 175 it would only turn 4800 WOT.
You should have seen the insides of the cylinders and exhaust housing.
At least a half inch of carbon build up....it was nasty!
How the motor even ran like that was beyond me.
Get the rpms up and it will burn much cleaner...
Turning 5800 rpms will not wear it out any faster,if anything it will prolong the life of the motor to be able to burn the carbon out.

 

[Relaxed427]

Re: 1986 Evinrude 110hp V4 Prop Help

While I am at it- whats the best way for me to check for carbon buildup?

 

[Dhadley]

Re: 1986 Evinrude 110hp V4 Prop Help

The engine rpm has to do with combustion temps with todays fuel. Lugging raises the temps beyond design parameters and will result in coking which can lead to broken rings, as mentioned in above posts. When the fuel had lead it wasn't an issue since lead is a combustion temp coolant to some extent. Once the government "got the lead out" things changed.

The best way to check for carbon build up is to run Sea Foam or Engine Tune thru the motor. A good de-carb session will eliminate any that might be there. Then you know you're starting with a clean motor.

 

[Relaxed427]

Re: 1986 Evinrude 110hp V4 Prop Help

Great help guys.

I did take a look at the A/V plate, and it is at right about level with the bottom of the hull.

I am going to talk to the marina about borrowing a prop or two.

In the meantime, I will be adding seafoam to the next couple tanks, and looking for a carb kit. I feel like I should do the carb kit anyways.


Thanks for the help, I shall report back with results.

 

[72SideWinderSS]

Re: 1986 Evinrude 110hp V4 Prop Help

While I am at it- whats the best way for me to check for carbon buildup?

http://forums.iboats.com/showthread.php?t=302825

Great help guys.

I did take a look at the A/V plate, and it is at right about level with the bottom of the hull.

I am going to talk to the marina about borrowing a prop or two.

In the meantime, I will be adding seafoam to the next couple tanks, and looking for a carb kit. I feel like I should do the carb kit anyways.


Thanks for the help, I shall report back with results.

Before changing props, I would work the setup and see what you can get with the existing prop. i.e raise the motor one hole up at a time and test run the boat at wot (Keep an eye on the water pressure). Sounds like you might be able to raise the motor up a couple of holes at least.

I agree on the carb kit.

 

[Relaxed427]

Re: 1986 Evinrude 110hp V4 Prop Help

Thanks Jimmy.

I read that link, and my motor does have the schraeder valve on it. Is the seafoam method still good, or is the BRP treatment better?

I think I will be experimenting with this all tomorrow- it looks like it will be a nice day.

 

[72SideWinderSS]

Re: 1986 Evinrude 110hp V4 Prop Help

I Generally do the 3/4 gallon of gas, 2 1/2oz of oil, and 1 can (12oz) of Seafoam routine myself ( I use a seperate gas can ). Start motor on regular premix, let it warm up, switch to the Seafoam mix, run (idle or under 2500 rpm if in the water) for 15min, let sit (off) for 15 min, do again with seafoam for 15 min, let sit (off) for 15 min, repeat until gallon is consumed. Switch back to your normal tank, let it run until all the seafoam is out of your carb's, take it out for a WFO spin, enjoy.

Oh Yea, This is going to produce copious amounts of smoke, be advised.

 

[Relaxed427]

Re: 1986 Evinrude 110hp V4 Prop Help

Hey again everyone,

I was able to work on the setup a little more. I jumped the gun earlier though, and purchased a used 13 3/4in X 15 pitch prop. I put that on the boat, and am very happy. I get up to right around 5800rpm at WOT (maybe a hair over). The holeshot is much better, and I top out at around 40mph GPS.

I did run quite a bit of seafoam through the engine- and the smoke is amazing lol. People were giving me the evil eye for it. hehe.

I have a carb kit, and will be doing those over the weekend I hope.

My question today is, should I switch props back to the 19 pitch and attempt raising the motor and trying to improve that setup, or should I mess with the motor height with this new 15 pitch prop?

And I noticed my motor mounts to the transom with a wedge plate underneath it, the wedge being thicker towards the top. Is this another thing to mess with, or generally a good thing regardless?

Thank you all so much, at this point The boat is performing so much better I am extremely pleased, but if a little more adjust will help- why not right?

Have a good one!