2011/12 Z9 New Tempest+ 25P, PVS plug question

[DixieChicken]

So I finally bit the bullet and went for the Tempest+ 25P based on numerous recommendations of the performance on the Z9 (with 250 Pro XS).


Didn't ever have any plugs for the Fury that was on there, so that was a non-issue.

However.... the Tempest came with 3 'open' plugs. No plug kit, no various diameter openings to play around with, just the three that have a good ½" hole (or more).

Anyone have any input there as to how they'd perform on my setup?

The setup is in my sig, Bobs 12" with hole shot plate is how the Merc is hanging.

When I bought the boat it had NEVER been run over 5200, EVER, and even then it was .1 of an hour! The highest cruising speed that it'd done for any length of time was closer to just over 5000. That was because the throttle linkage wasn't adjusted correctly and it just wouldn't run that fast. I fixed that and it instantly went to 5400 with 2 of us, and fully loaded. (Even with 50~65 gallons of fuel.)

Thing is.... I know that it should be running more rpm's, as well as faster on the water. I've gotten it to 67 and that's all she'd do. But I've yet to try a speed run with ¼" or less of fuel. I'm just too cheap to buy fuel on the lake, so we usually fill it up, (unless it has ¾ tank) before we leave.

Just curious about the plugs in the Tempest. Thinking I might need them for the hole shot being as it has a good bit less bite than the Fury.

I realize once running on plane the plugs don't really come into play. Just that I don't want to have to mess around with it in 50° water.

Figure this one you'll know Bryan.

Not going to the lake right away because I'm running new fuel lines. Sadly, it looks like it'll be a couple weeks now, being as it's scheduled to rain this weekend.

Thanks in advance guys for the help!

[BMCD]

So u just want to know which plugs to run on a 25p Tempest. Normally they come with med plugs, I always removed one plug.

To really know you need to tell us your rpms on Holeshot at full throttle.
Also need to know what your motor height is, your prop shaft to pad measurement. I would start with this b4 we even mess with plugs.

[DixieChicken]

So u just want to know which plugs to run on a 25p Tempest. Normally they come with med plugs, I always removed one plug.

To really know you need to tell us your rpms on Holeshot at full throttle.
Also need to know what your motor height is, your prop shaft to pad measurement. I would start with this b4 we even mess with plugs.

Thanks Bryan (sorta figured you'd jump in here).

My P2P I've played with throughout the throw of the Bob's plate. Thing is, the Fury wouldn't blow out, and wouldn't gain anymore RPM no matter where I put it, nor where I trimmed it. I mean I could run WOT with trim at 5.5 and raise the plate where I thought it was pretty darned high, still wouldn't help. Don't have a gauge, so this week I'm putting some marks on the plate so I have at least an idea.

Finally got the new fuel hoses & bulb in today. Although the hoses were the 2011 version, and I didn't see any sign of corrosion, gunk, etc. Had a problem last time we were out with running under power. Put in down by the dam and been fishing half the day on Oconee. As we worked north, we ended up at the BBQ place up my Hwy 44 for lunch. Went to leave after pulling back under the bridge and it wouldn't get up on plane. It stuck at 3100 and wouldn't get up. Slowed down and had my wife pump the bulb (which was really soft) and it went to 4100 on WOT, got it on plane FINALLY and made it back to the south end of the lake to load it up.

Spoke with Don and he suggested changing the lines and filter. Also rebuilt the pulse pump. Figure I'll clean out the VST tomorrow as well.
Thought I might have gotten some water in the fuel, but pumped out a jar full that's been sitting over a week.... and it's perfect.

[BMCD]

Bob's should have a measuring tape inside of the plate. On my 2011 the Fury was not the best option for me.

[DixieChicken]

Bob's should have a measuring tape inside of the plate. On my 2011 the Fury was not the best option for me.

Yeah I remember you saying that last year in a thread. Just took me a season with that darned Fury before I'd had enough.

The Fury is in great shape, (9/10 easily) so I figure I'll send it to be worked. Once I get some time with this new Tempest it should give me a point of reference to discuss with the prop shop which direction to go.

[tzx200]

I have never ran the tempest but I can tell you my fury didn't like to run high she fell on her face if I went higher than 3 1/4 - 3 1/2"...Had no lift but good RPM's. I run the fury about 3 5/8" and she rips out of the hole and with just me and 1/2 tank ill see 71-72 with a full tourney load and a 300+ lb. partner and his gear 67-68 all day long.

I don't see a reason for me to try a tempest I doubt ill et much more than this.

[BMCD]

I remember similar results on my 2011 and a Fury, liked to be below 3.5. But weight and higher settings killed lift, the Tempest will make it more consistent, or should make it.

[tzx200]

yeah we spoke about that Bryan that fury cannot run high they have to be deep or that big boat will fall...

[DixieChicken]

Bob's should have a measuring tape inside of the plate.

That's where the problem is, sorta.
There is no tape on the inside of the plate.

Searched for one on-line and can't find one. Think I'll go to the local sign shop and have them make me one using yellow reflective material (so I can see it at night as well).



It's rained so much, for so long these last couple weeks I've been thinking of changing my name to Noah and getting into the ARC building business!

Looks like we're having a bit of a break tomorrow afternoon so I'm gonna' hook her up and make a trek to Jackson to see if replacing the fuel lines, cleaning the VST, and rebuilding the pulse pump helped.

Along with the new Tempest of course.

[DixieChicken]

O-taaaay...... multi-pronged approach here, bear with me.

So finally worked out all the bugs in how the ol' girl was running. It laid down on us last month when we were on Oconee. We'd been out all day, went north and grabbed BBQ at a place on the lake. Went to go back south and it sounded funny when I cranked it up. Idle was a bit low, and surging 50~100 RPM. Could also smell a more raw fuel, which many say is a tracker valve. Went across the lake slowly to fish rip rap, then after going back under the bridge it wouldn't come up on plane.

At first it wouldn't run but 3100 RPM, but after my wife pumped the bulb I managed to get it to 4100 and that was all it'd do. FINALLY got on plane and made the 15 mile trip back to the ramp.

The run problem came on suddenly and it wouldn't run but 4100 @ 45 MPH no matter what. That was with the Fury.

Ended up changing out lines, bulb, pulse pump, cleaned the VST, change the fuel filter.... and it still wouldn't run right. The VST was surgically clean though when I opened it up, which surprised me. Took two different fuel samples, one from the tank, the other I poured from the VST. No water in either.

Changed the prop to the Tempest when I did the lines and pulse pump. Went last Monday after doing that and RPM's moved to 4300~4400 @ 47MPH but still didn't have power like it should, and just wouldn't rev. Hard to get it back on the trailer as well.

The Tempest absolutely has more RPM.

So next I knew I needed to at least check the plugs, and figured might as well do the tracker valve diaphragm. Noticed #5 was wet coming out. BINGO......

Should have looked at them first!

Once I found the wet plug (

plugs didn't have but MAYBE 30 hours on them

) I knew I'd found the problem. Went ahead with the tracker valve diaphragm being as I already had it out, and had a new one here, Went ahead and replaced the plugs, as well as #5 coil Saturday. Also
fine tuned the throttle cable to make sure I'm getting 100% at WOT.
Back to the lake Sunday. Normally when checking run problems it's easy to just run to Jackson as it's close. But my wife was so sure I'd fixed it,

she wanted to go to Sinclair Sunday so we made the 90 minute drive. Fired right up, and it idled right (no surging) and ran a LOT better. Running MUCH better, but still can't get the extra RPM I think it should.


Fury 26P:
The Fury never had the PVS plugs so I didn't have any choice but run without them. Now THAT puppy just didn't blow out no matter what, and jumped up on plane every time. Top RPM's with the Fury was 5400 by myself, ¼+ tank it'd run 64. With two of us and loaded heavy I'm thinking maaaaaybe 58, but that was with

at least ¾ tank if not almost full.

Keep in mind that the Z9 has a SIXTY SIX GALLON tank!

Not hard to have 520 pounds of fuel in that puppy!


Tempest 25P:
Running 3¼"~3½" P2P, it was pulling 5500~5600 @ 62 MPH in a medium heavy rain, fairly windy, decent chop with two of us, loaded HEAVY with gear, 5/8 tank, with 5 lead acid batteries in the back. Didn't have that 5th battery with the Fury on the 64 MPH run. Honestly.... it was hard to look at the RPM's Sunday as I was holding on to my rain hood trying to keep the flap from covering my friggin' EYES!

Wasn't planning on getting caught in the rain, but sure glad our daughter gave us Save Phace's for Christmas!

I've got PLENTY of water pressure being as I just replaced impeller before the trip to Oconee where it started running funny. I can go as high as high as 2" P2P (or maybe higher) and still have 15 pounds of water pressure, so that's not an issue..

It feels better though with the Tempest as far as getting up on the pad, and just running smoother. Just that feeling where you feel the air underneath and all is well.

As far as the PVS plugs though, running with only 1 pulled thus far. Have to be careful not to blow out coming out of the hole however. My wife drove it a few times, and

every time

she ended up blowing out.

Although once she hadn't trimmed back to 0 before gassing it, which was of course the worst blowout

. (Actually triggered a short beep.)

Like I said earlier, the Fury just didn't blow out.

Still thinking though that there should be up to 400~600 more RPM there somewhere. I mean I don't really care if it's not running 72, (with my wife in it at least) but I'd like to see more if it's there.
(For when I'm feeling froggy.)

I'm thinking of pulling all three plugs for the hole shot at least and seeing what it does.
Ideas????


Thoughts:

Don't think any internals are off on the Merc as far as say.... low compression, although I've not seen the reeds. Did a compression check at 221 hours and they were 130~134 throughout. It's got 259 on it today and honestly.... it sounds a bit better than it did then.
The guy that checked it said he'd not seen one that good, with that many hours in 4~5 years!

All the filters, in-line oil, oil pump, fuel filter etc were changed in August. Changed the fuel filter again last week.
Think the bulb was an issue (leaking a bit of air) and indeed there was a stronger than normal fuel smell in the boat when it'd been sitting under the cover (and/or inside). Also think that coil was going bad all along. I *do know* that when I purchased the boat (with 221 hours) and pulled the data, that it had never been run WOT. It had .1 hour at over 5100 and spent most of its time down in the 4200~4600 RPM range with very little time between 4800~5000. I got to looking and the throttle cable had NEVER been adjusted properly and it was getting about 80%~85% max. Previous owner was 68 when he bought it, 71 when he passed away so I know he wasn't dogging it out for sure. Throttle cable was a quick fix.... I flipped the lever and twisted the adjuster a couple turns and instantly gained over 400 RPM. Finally broke down last week and fine tuned it to the Service Manual spec so I know I'm getting 100% now.


OH..... Forgot to mention that I marked the plate so I can see where it is now. It did have a silver tape on it, but it didn't really make any sense as far as P2P, plus I couldn't see it. I did the measurements right, (with a 5' level) and marked the plate every ½" on BOTH sides, referencing the P2P measurement (rather than some random top to bottom 1"~6" rule) so I can at least see what is going on!

[jasonG]

Gotta get rpms up. You should be hitting 5900 if your going all out.