Porpoising problem

I have been reading some older posts here and haven’t been able to figure out a solution to my problem so I’m looking for suggestions.

I have a 2001 Ranger 619vs with Merc Optimax 200
New merc pro kicker 9.9 with power tilt & trim
2 batteries are on the starboard rear and one is on the port rear
Porpoising has always been an issue since I bought it used 3 years ago and now it has gotten worse since the new kicker I believe is a little heavier than my old 9.9 big foot since it didn’t have power tilt

I run a Tempest 21p prop
I normally have had to always run the boat 3/4 – full down on the tilt to eliminate the porpoising.This happens even when the rear live well is empty.For whatever this is worth, I can say that when I do get it trimmed out right and its running good, the porpoising starts again once I slow down a bit or even more when I slow down even more coming into a spot or back to the landing.
Do I need to install a foil?
If so, which one?
Do I need to run a different prop/pitch? If so which one?
Do I need to change which hole the trim pin is installed in on the motor plate?
I’m always playing with with the trim to make adjustments and its getting frustrating and the motor sounds like its working harder when trimmed all the way down.
Any help would be appreciated

Many times when porpoising is not able to be fixed from trimming and weight balance adjustment, it is caused by the motor being mounted too high or low, usually low.

The motor working harder at low trim is a good indication it is too low.

I’d try a 19p…. do you run wot much ?

It seems like most of your weight is in the rear. Is it better if you have someone with and they sit in front or fill the front live well?

big_g wrote:

I’d try a 19p…. do you run wot much ?

I don’t usually.
Mostly 3/4 throttle

I just have a bait well upfront and never tried filling that
I usually have the other person riding in the seat next/across from me at the console

Not a perfect comparison, but i was running a tempest on my 681 and porpoising was an issue at anything other than WOT. I got a new prop from Croxton props (google them) and the problem was solved. Mark Croxton will call you and discuss the issue, then send you the prop you need. It could be a motor height issue, of course, but if it’s the prop I’d recommend Croxton.

I installed the stingray classic hydrofoil on my boat last year and it solved the problem. My issues seem very similar to yours as I added a kicker to mine and it got worse. Until I added the foil of course.

I know that trim tabs are the right solution but I wasn’t in the mood for another $1000.

I did break my hydrofoil last season but I’m guessing it had something to do with the 30 mile ride in 4-6′ waves on superior. They’re covered by a lifetime warranty which they honored in about 4 weeks.

I recommend it. I certainly will not hurt.

Just for comparison, here’s my boat. I will also add that I was able to stay on plane at 10-12 mph which is awesome when battling 4-6 footers.

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Maybe try a Rev 4 21 pitch, should help carry the load a little better and give you a bit better now lift.

It sounds like you have way to much weight in the rear of the boat

I agree with Munchy. It sounds like your motor is mounted to low.

Two things to look into. First as mentioned the motor height. Secondly the rake on the prop. I would think Ranger would be able to tell you which prop should work best for that hull.

Rake, not pitch, affects how much bite the prop is able to hold while trimmed up. More rake equals more bite. It allows the driver to add more trim. More trim equals more bow lift.

You might find that a prop with less rake may work better. Less rake effectively creates stern lift. It does this by forcing the driver to use less trim. It is also more efficient. Rake creates more resistance in the water. Less rake means less resistance which means more of the motor’s torque is used as forward thrust. Therefore, less rake can sometimes allow the boat to go just as fast with less trim due to the efficiency gained.

I think the Tempest gets into Merc’s medium to higher amounts of rake.

I learned this trying to diagnose a tin boat where I found less rake, a Vengeance prop of the same pitch, reduced the amount of bow lift, effectively raising the stern, removed the porpoising, better planning, and kept the same top speed.

Can you check with Ranger?

I often wonder why people just don’t toss a big counter weight in the bow to balance the boat better, especially the bigger rigs that could handle a 50-85# chunk of steel in the bow.

My boat is under powered and over weight. With four batteries two of them need to be in the front or I’d have the same problem.
I also had a mechanic install my motor low once too after he redid my transsom, took two trips to figure out what changed.

I find I’m generally clueless when it comes to prop talk so count me out on contributing on that front.

Although the final answer may be a different prop,
weight redistribution would be free,
try moving all the weight you can from the rear to the front of the boat.
for top end speed you do want the weight in the back,
but for hole shot, you want it forward.
since you are having lower speed issues
the first thing i would try is moving some weight forward.
tackle, anchors,
the big guy next to you (to at least test the possibility).
again, it’s a free fix.

I agree with everyone on the weight adjustment but I’m my case I was very limited to what I could move and when I added an anchor or two to the anchor compartment in the bow, it didn’t help anyway.

The kicker seemed to be the culprit for me.

Hydrofoil is the next cheapest.

biggill wrote:

I agree with everyone on the weight adjustment but I’m my case I was very limited to what I could move and when I added an anchor or two to the anchor compartment in the bow, it didn’t help anyway.

The kicker seemed to be the culprit for me.

Hydrofoil is the next cheapest.

I’m thinking the hydrofoil option next as well since I am limited also on where I can move batteries to the front and really don’t want to re wire everything

bullcans wrote:

I can say that when I do get it trimmed out right and its running good, the porpoising starts again once I slow down a bit or even more when I slow down even more coming into a spot or back to the landing.

May be just the nature of your particular set up. I have driven a lot of Rangers and this is pretty common. You need to start your trim down before pulling back on the throttle.

You may not want to do too much tweaking. I think the 21P Tempest is a proven prop for that boat/motor. What it does give you is a hell of a lot of bow lift when you need to crush 4 footers for 10 mile runs! You need that fairly quick punch occasionally so you are not constantly spearing waves. If you raise the motor you will probably lose that ability to get that bow up at slower speeds.

Have you posted this over on Walleye Central? There are a lot of Ranger pros who watch that Boat / Motor forum. You may get some other options. If you have a Facebook account, try looking up Ranger Pro Eric Olson. Guy know his stuff.

Good Luck.

-J.

I have a 1999 692VS w/ windshield and a 175 EFI propped with a 21p 4 blade tempest. Not much different in specs from your ’01 619. The back end is loaded with gear and I have not had any issues with porpoising. My gas tank is up front and I believe yours is the same. I don’t think it was changed until 2004.

When running WOT I have the motor trimmed up almost to the point it sprays water like a jet ski. If I back off the throttle without adjusting the trim, the front end will bounce quite a bit. By trimming down as I back off the throttle that issue completely goes away. Are you adjusting the trim as you’re slowing down?

Might consider adding a jack plate while you’re moving the motor around…

I would suggest a hydrofoil of some type. There are a few different ones/brands look into them and see which one is best for your situation. A friend of mine had a 619, it was around a 2005, give or take a few years on either side. I remember that boat pounding the snot out of you if there was a chop. His has since upgraded to a 621 and that boat rides a little better.

This is the one I went with after some research.

http://www.stingrayhydrofoils.com/stingray-classic/

I considered this one but the reviews said the no-drill mount was not reliable and some people said it simply fell off.

http://www.stingrayhydrofoils.com/stingray-stealth/

I talked to a couple of Ranger dealers today and it sounded like my prop is the right one, my motor height is correct, weight distribution is pretty good. They both said no to a hydrofoil and no to changing the prop.

Joel VandeKrol wrote:

I have a 1999 692VS w/ windshield and a 175 EFI propped with a 21p 4 blade tempest. Not much different in specs from your ’01 619. The back end is loaded with gear and I have not had any issues with porpoising. My gas tank is up front and I believe yours is the same. I don’t think it was changed until 2004.

When running WOT I have the motor trimmed up almost to the point it sprays water like a jet ski. If I back off the throttle without adjusting the trim, the front end will bounce quite a bit. By trimming down as I back off the throttle that issue completely goes away. Are you adjusting the trim as you’re slowing down?

Might consider adding a jack plate while you’re moving the motor around…

Good point Joel. I actually don’t trim down when I back off the throttle until it starts porpoising. Sounds like I’m adjusting the trim after the fact. Thanks for the tip!

I’m curious why not a hydrofoil. I’d like to know for my own benefit.

Very interesting topic. I want to upgrade from a 2025 pro-v to a ranger eventually. Why is this such a common problem? Any years and models that don’t have this trend?

biggill wrote:

I’m curious why not a hydrofoil. I’d like to know for my own benefit.

Both dealers told me that performance and speed would be affected on my Ranger and wouldn’t have a positive impact on my particular boat and that hydrofoils were not needed on Rangers.

Biggill your boat may be a totally different story as it sounds like the hydrofoil did great things for you and I’ve read its done the same for others. That’s why I thought it would cure my issue but the Ranger guys said no, so I’m stuck thinking its my operation of reading the boats’ reaction and reacting accordingly.
I’ve always owned aluminum boats previously and didn’t have to play with the trim as much as I do now since I own a fiberglass boat. Maybe just a learning curve, I don’t know.

basseyes wrote:

Very interesting topic. I want to upgrade from a 2025 pro-v to a ranger eventually. Why is this such a common problem? Any years and models that don’t have this trend?

Good question basseyes.
There are many more experts out there other than myself (which I’m not an expert in anyway) that can answer this for you. By no means am I knocking Rangers, as I think its a simple thing but I just haven’t figured it out yet. Thus the reason for me reaching out to the IDO guys for suggestions.

bullcans wrote:

Both dealers told me that performance and speed would be affected on my Ranger and wouldn’t have a positive impact on my particular boat and that hydrofoils were not needed on Rangers.

Thanks for letting me know. I guess it all depends on what you are hoping get in the end. For me, losing a few mph on the top end doesn’t bother me a bit. I really wanted improved hole shot, improved low speed control in big waves and to stop the damn porposing.

I’d bet I’ve lost some mpg too but I bet I gained it all back and then some in rough seas. I’m not a prop snob either so I couldn’t comment whether or not it would do any good.

Good luck and let me know if you have any questions.

I have no clue to the situation, but it’s fairly common for reps to protect the image of their companies.

You start having rangers show up to tourneys with hydrofoils or other stuff to fix an issue with their boat that reflects poorly on them.

So if they say no to hydrofoil then what? It seems crazy to spend that kind of money on a boat and have to trim this down, that up, while on plane do this or that.

Just my 2 cents, I bow out now.

What the hell does a ranger dealer know, they sell rangers for a living, not hydrofoils. When is your boat proposing? Only when slowing down? At a certain RPM? Throughout the whole power range? The only drawback with a hydrofoil is that you have to drill some holes in the anti cavitation plate. I put one on my 2025 prov and it has allowed me to keep the bow higher at lower rpm’s in big waves. Living here on mille lacs, every now and then we have some big waves.