Not enough power from my 4.3L Mercrusier

[sirchad]

I don't seem to have enough power from my 4.3L Mercruiser 2002 Monterey Edge 180. I can get up on 2 skis but not 1. This boat is new to me and it seems to take too long to plane. When it's trying to pull me up on 1 ski it never came to plane and I was never able to fully get up on the water(only the driver was in the boat). It doesn't have those trim tabs on it. I only weight 175lbs so I believe I should be able to get up on a single ski with this boat. Without towing anything it tops out at about 50mph and the engine sounds good. We played with the trim but wasn't able to improve it enough to get me out of the water. Any suggestions would be great.

 

[RogersJetboat454]

Re: Not enough power from my 4.3L Mercrusier

Welcome to Iboats.

What's the RPM the engine hits when you have it wide open?
What's your propeller pitch?

 

[Don S]

Re: Not enough power from my 4.3L Mercrusier

I moved this to the prop forum. The fact that it goes 50 mph without a load means the engine is fine.

 

[Utahboatnut]

Re: Not enough power from my 4.3L Mercrusier

With only a driver and you at 175 the boat should have plenty to get you up. its probably the vortec v-6 right? is it carbed or fuel injected? either way should have more than enough. I would look at a prop change first before thinking about trim tabs. What prop are you currently running? with a 50 mph top speed i would guess it to be more of a cruising prop rather than a power prop. If you plan on doing water sports and dont mind losing a bit off the top end look into a HI-Five great prop for watersports. They are spendy and probably not required for your needs, even a good aluminum 3 blade with a lower pitch is where i would be starting. Let us know what you are currently running and we can go from there. Being in Texas altitude isnt a concern like it is where I boat(5000' asl).

 

[NHGuy]

Re: Not enough power from my 4.3L Mercrusier

Once you answer Roger's question we can be a lot more definite.

 

[achris]

Re: Not enough power from my 4.3L Mercrusier

Just looked at a picture of a 2002 Monterey Edge 180, and if that has got enough go with a 4.3, man something wrong, like prop WAY too big. As already suggested, post up what revs it's making at full throttle, and what prop is on.

Chris........

 

[sirchad]

Re: Not enough power from my 4.3L Mercrusier

Thanks for everyones input. So I'm not sure what the RPM is at when running WOT, I may be able to take it out tomorrow and find out. I just checked the prop and it is says: 48 832834A45 23P. I guess that means the pitch is 23. It is a 3 blade prop. This is a thunderbolt 5 ignition.

 

[UncleWillie]

Re: Not enough power from my 4.3L MerCruiser

Re: Not enough power from my 4.3L MerCruiser

Let's look at this another way just to cover all bases.

You didn't actually say it, but, how much slalom skiing have you done.
Have you gotten up consistently behind another similar boat.
You will be up at 10-15 the boat will start to plane at 15-20.
The boat will not get to plane until after you are coming up on the ski.
If you are plowing and drowning with to much rear foot, even 200 hp will not do it.
The technique is different from Combo Skiing.

Now if you are a experienced slalom skier, forget everything I just said!

 

[Tail_Gunner]

Re: Not enough power from my 4.3L Mercrusier

you have to much prop post your gear ratio its stamped on your outdrive leg....

 

[rallyart]

Re: Not enough power from my 4.3L Mercrusier

I agree with Tail Gunner. Too high a pitch. You may need to make sure that the moveable weight in the boat is forward to get a good hole shot also. Moving one adult from the back seat to the bow will make a big difference.

 

[jestor68]

Re: Not enough power from my 4.3L Mercrusier

If you run your numbers through the Mercury prop selector, you will come up with considerably less than 23 pitch, using the two gear ratios normally used with the 4.3L engine/Alpha drive in 2002.

 

[steelespike]

Re: Not enough power from my 4.3L Mercrusier

Prop calculator indicates that with a 23" prop the 4.3 is running about 4100 rpm. at 50 mph.
It would very likely have a sluggish hole shot and do poorly at water sports.
With your actual rpm we can tell better what pitch you need.

 

[sirchad]

Re: Not enough power from my 4.3L Mercrusier

I am a fairly experienced skier. I tried to shift my weight to the front foot as much as possible.
There was only the driver in the boat with no extra items weighing the boat down in anyway. The gear ratio is 1.81R.
From the sounds of it everyone agrees a different prop is needed, lower pitch. Suggestions would be welcome. 3/4/5 blades. A high five was recommended but that looks like its gonna be pricey. Thanks again everyone.

 

[achris]

Re: Not enough power from my 4.3L Mercrusier

19" Laser II, with the vent plugs removed... That puppy'll pull your arms out of their sockets...

 

[jestor68]

Re: Not enough power from my 4.3L Mercrusier

Since you are currently running an aluminum Mercury prop, and may not want to invest $500 in a SS prop; my suggestion (for the most bang for the buck) is a Solas Amita 15-3/10 X 19 aluminum prop for the pulling power you're after.

 

[achris]

Re: Not enough power from my 4.3L Mercrusier

Since you are currently running an aluminum Mercury prop, and may not want to invest $500 in a SS prop; my suggestion (for the most bang for the buck) is a Solas Amita 15-3/10 X 19 aluminum prop for the pulling power you're after.

You and your Solas props again.... They are cheap because they are crap.

 

[steelespike]

Re: Not enough power from my 4.3L Mercrusier

There is an extended history of successful Solas Amita and Rubex installations. Several that I recall going from 3 to 4 blade
and retaining the top speed.The reason we recommend them is not because they are cheap but because they work.
If you think its crap because it doesn't do what a the Lazer will, at $500 the Lazer should be better.
I believe the Solas Amita is competitive with a entry level ss prop at 1/3 to 1/2 the cost.

 

[Tail_Gunner]

Re: Not enough power from my 4.3L Mercrusier

I don't seem to have enough power from my 4.3L Mercruiser 2002 Monterey Edge 180. I can get up on 2 skis but not 1. This boat is new to me and it seems to take too long to plane. When it's trying to pull me up on 1 ski it never came to plane and I was never able to fully get up on the water(only the driver was in the boat). It doesn't have those trim tabs on it. I only weight 175lbs so I believe I should be able to get up on a single ski with this boat. Without towing anything it tops out at about 50mph and the engine sounds good. We played with the trim but wasn't able to improve it enough to get me out of the water. Any suggestions would be great.

Ok lets start over

18' boat 4.3 190hp 1.81 drive...23p prop...50mph. And it cant pull a single up...Only two known issues...8 people in the boat while your sking or your engine need's a tuneup

If you want to clear this up.

ESSENTIAL DATA REQUIRED
When posting a question about propellers, you cannot get a reasonable answer unless you provide the following information in your post: Items 1-4 are essential for meaningful response to most questions.
1) Performance issue you are trying to correct.
2) Current prop manufacturer, model, aluminum or stainless as a minimum.
3) Current prop diameter and pitch (required).
4) Wide open throttle RPM and speed with an average load (very helpful)
5) Engine/drive make, model, year, and HP
6) Boat make model, year, length and weight

 

[jestor68]

Re: Not enough power from my 4.3L Mercrusier

The Mercury prop selector calculates a 20 pitch aluminum prop will get 4600 rpm @ 46 mph. That was running it through either based on current performance and/or weigh. It came out the same both ways. I have not found the Mercury prop selector to ever be very far off.

I suggested the 19 pitch to get him up to 4800 rpm, since he is interested in water sports performance.

What brand of prop you purchase is your choice. I happen to favor Solas or Turning Point in aluminum props for their cutting edge design and casting technology.

 

[jestor68]

Re: Not enough power from my 4.3L Mercrusier

You and your Solas props again.... They are cheap because they are crap.

When I went looking at the various aluminum props appropriate for this application(19 pitch and 15" diameter), Solas was the only one to offer that size. Therefore, they won again.