2014 618 Pro 150 Merc fourstroke questions (prop and hole shot)

[Brando72]

Just bought a used 618 pro (not first bass boat, but 1st Phoenix) with a 150 Merc 4 stroke. I'm sure this question is on here somewhere, but I thought I would ask. My boat has a tempest 21p prop. It takes forever to get on the pad. It has a plug in the prop. I'm going to pull it and see if it helps any. I see where a few other folks on here have the same set up with a tempest 23p and no complaints and many more HP. I do not have a haydraulic JP nor have I made any adjustments yet. Anyway, the questions are: with a 21p prop why is it taking so long to get on the pad (my blazer 180 pro v had a 23 and had no trouble, but a two stroke)? What is the highest rpm i should be running on this 4 stroke? Thanks in advance. The rpms are up during take off also, almost as if the props cavitating.

[Tom Edwards]

first check the prop to keel measurement, state it here and people can help. What is the RPM at top speed? What is the RPM at breakover? Does the RPM go up a bit or a lot at break over? How much/to what RPM?

[Brando72]

I'll have to find out where to pull the measurements from. I can get the rpm to 5800-6000. At breakover the rpm is low until it planes out then the rpm comes up as i trim it up. I'm going to pull the plugs and start from there. I'll try to get more info on the prop to keel measurement.

[fisher_hunt]

I had holeshot issues when loaded down with my 618. I'm running the 175 SHO. I added a hydrofoil and it made a huge difference. These 18ft boats just don't have enough weight up front. The hydrofoil helps keep the bow down when you punch it. Once you confirm that your prop to pad and RPM's are were they should be and still having problems then I would look at getting the hydrofoil. More expensive options, you can switch to lithium batteries to lighten the load or try a 4 blade prop like the bravo.

https://drewcraft.com/product/bailey-hydrofoil/

[JR19]

The very first thing I would do is remove the vent plugs from the prop. Opening the holes allows more exhaust gas to reach the blade surface. This creates aeration which in return allows the prop to slip a small amount and build rpms faster...now it's a fine balancing act. To much aeration and you lose bite, not enough and you don't build rpm's. FYI PVS holes only play a factor when you punch it to get on pad. The initial punch of full throttle sends a lot of exhaust out the prop. Sending some of the exhaust out the PVS holes help the prop build rpm's. Once on plane all exhaust goes out the barrel and none goes out the PVS holes. PVS holes only play a part in hole-shot.




Prop to pad does play a small role in hole-shot. I have no idea what the suggest PTP for you rig is because I have no experience with Phoenix. Hopefully someone with knowledge about your combo can give a suggestion...here is how to measure PTP...

[Brando72]

Thanks, this is a big help. Will get started on it this weekend.

[Brando72]

Thanks, I'll go through the process of elimination now. Will look into the hydrofoil.

[JR19]

I am not against having a hydrofoil because they do work and I do have one on my set-up...however I am in favor of getting what you have dialed in the best you can before adding one.

[Brando72]

first check the prop to keel measurement, state it here and people can help. What is the RPM at top speed? What is the RPM at breakover? Does the RPM go up a bit or a lot at break over? How much/to what RPM?

3500 when trying to plane out. All the plugs are out of the prop. After it planes out rpm's come up quick. Prop keel measurement is 4 1/8". I keep it below 6000 rpm because I don't know what the recommended max rpm is. I'm going to raise the prop to keel 5/8" to 3 1/2. Will try to dial it in. Still think I need a 23P fury.

[Brando72]

Think I have found the problem (event though i don't think anyone is following this anymore). Weight distribution. Between the: batteries, power pole control box, both live wells being full (have plugs in them now), Me (190lbs), my son (215lbs), and the boat only being 18', its too heavy in the rear. Lightened the load and it came up fine. Still going to jack the motor up another 3/4" to get the prop to pad at 3.5"s. The 21p tempest blows out a little in the turns (yes, I trim it down a little) and rpm's out too quick so I am going to go with a 23p fury and have it tuned to the boat. All this while fishing of course. Any advice or comment will be appreciated. Fish on guys.

[Coke]

I have a 2011 PHOENIX 618 with a 175 Pro XS and a Tempest Plus 23p, my P2P is at 3 1/2". I had to move some stuff around in the storage compartments at first to balance the load out, and all the compartments are full, now it'll jump up on plane and run a steady 65 mph.
Just keep playing with it, you'll find that sweet spot.

[Brando72]

I have a 2011 PHOENIX 618 with a 175 Pro XS and a Tempest Plus 23p, my P2P is at 3 1/2". I had to move some stuff around in the storage compartments at first to balance the load out, and all the compartments are full, now it'll jump up on plane and run a steady 65 mph.
Just keep playing with it, you'll find that sweet spot.

Thanks, sure wish mine had the 175 pro XS on it. First mercury I've ever owned. Mine is just a 150 four stroke. I don't think or know if it is a Pro XS. Shows how much I know about mercury's. I am still pleased with everything though. Especially the boat. Rides a lot better than my 180 pro V but not as fast.