Low RPM issue

Recently purchased a boat with a 2006 Mercury 200 hp, max rpm I’m getting is 4900-5000... mph only 52. Boat is 18.8 feet and should be running 62-68... any ideas what the issue could be? Recently had new powerhead installed and full tune up. Thanks

I take it back to the ones that did the work,...ask them.

I didnt put the powerhead on, I just purchased he boat from Atlanta and drove it back here. Has A 25p fury prop. I am emailing the place the guy said the new powerhead was put on to try and get info. I’ve got a bad feeling I’ve been scammed... and out 18k on boat that really doesn’t have a new powerhead on it. I say this based off some other issues I’m having with Boat and the seller. So I’m trying to narrow down some other possible reasons, so please no more smart remarks. Thanks... something helpful would be appreciated.

You need to be specific on what you’ve got.
And new powerheads are easy to spot.

2006 champion 188 w/200 HP Mercury Optimax 2006 medel. 25p Fury 3 blade prop. Boat has a 10 inch jack plate. Max throttle it’s getting 4900-5000 rpm. Running smooth though. Thanks

The exact right setup on that rig is a 25 tempest
Set close to 3 1/2” prop shaft under pad will run right at 5,700 rpms and 70 mph.

You’re not there. Find a merc tech and spend some money to verify what you were sold. A thousand possible issues could cause your problems but diagnosis over the internet won’t get it done.

Thank yoi

Your PM box is full.

If you're interested in a Tempest Plus 25, I have one that I want to swap for a 23. I realize that is not what you have so I would sell mine and get a 23 somewhere if you're interested.

when you took it out an tested before the purchase did it run up to the correct rpms an speed ?

Unfortunately I drove to Atlanta to purchase and did not take it on the lake. Hooked it up to the hose to make sure all worked and so on. I also failed to crawl under boat, and found out the hard way once back in Fort Worth, the seller failed to disclose fiberglass damage that needed repair! This has turned into a expensive nightmare., and a lesson learned. Guy is supposedly a guide in Atlanta Georgia area, but when I look him up I see nothing about guide service. Seller tried telling me I did the damage to the hull (was on inside of bunker, can’t see from the side), which I am 100 percent sure I did not. He got me good, but now I’m stuck with it so it has to be fixed. I’m in contact with the business owner where he said he got the remanufactured powerhead, he’s gonna contact me tomorrow and said he will assist any way he can. I know, I’m a [censored].

Are you a member on BBC? If not, join and go the the Merc page and check out the hotfoot setup section. Could be possibly part of the problem, not achieving WOT due to not being adjusted properly.

Have you done a compression test? Gauge is cheap and it’s easy to do, just make sure you do it properly.


And don’t feel bad, I got bamboozled too buying a used boat. It’s lessons in life that teach us for next time.

Don’t beat yourself up on this, it’s happened to a lot of us, including me. When buying used boats, it’s sometimes impossible to catch every single issue. I bought my first boat years ago, and the motor ran perfect on the hose and the compression was a perfect 125psi on all holes, thought I had me a decent boat. Next thing I know my number 6 piston shatters to pieces due to a water jacket problem. The seller obviously didn’t mention anything about this, and who knows, maybe he didn’t know about it either. Anyway, I hope your motor is an easy fix, it does sound like it could be something simple like a throttle cable adjustment. Best of luck to ya.

Well the fiberglass repair is estimated at 800 to fix, not as bad as I thought... but enough to still [censored] me off. Haha Taking the motor to Ronnie Patterson next week after the fiberglass is repaired. I’ve heard nothing but good things about his abilities with Mercury motors. Thank you!

BIG difference between "new" and "re-manufactured"
I sure as hope he didn't have some sleaze like Blackbird do that.

When you took the cowling off did it look clean or did you see orange gasket sealant everywhere?

And by all means you need to out this dude, this is not a large circle we walk in, and nothing I despise more than someone being taken advantage of, especially because of a lack of knowledge.

Sellers name was David Keith Sansbury... out of Atlanta,Ga and previously Satsuma, FL. He says he’s a guide, but I can’t find anything in relation to him being a guide and says he gets the Power Poles for his new boat at guide discount price. Pissed me off when he tried saying I was a scammer after I had already paid the man 18k. I’m a police officer and would never scam anyone, and I should have been more smart about the situation and had it all checked out and crawled under the boat. Was a long drive and I was in a hurry to get back on the road to Texas. We had texted multiple times and I let my gaurd down. Lesson learned for sure!

Champ family is pretty close. I’ve got friends there we can have a friendly chat.

In the meantime you need to get that motor to a merc tech before you run it. Lots of things can blow one up.

Is your boat red and white?
Gotta make sure we're sure about this.

Been there !

Pat Goff, my dad (Dan Telesko)is on the champion boat owners Facebook as well, he has an older champion. He showed me the discussion and yes it is the same guy and boat. I’m curious as to if anyone else went and saw this boat in person from that forum. The seller told me I was the first to look at it. The seller (David Sansbury) texted me this morning about the damage to the hull, and told me to call him at 11:30 bc he may have his insurance fix the damage but would need to be by a reputable rep. (Basically saying he knew it was there, otherwise he’d be committing insurance fraud) Boat goes to a mercury mechanic on Monday. Thank you!

Well, I am glad he's responding. Really glad.

The seller (David Sansbury) contacted me in reference to the hull damage on the bottom of the boat. The boat is currently at classic fiberglass and getting repaired and the seller is doing the right thing and paying to have the hull damage properly repaired. I should get the boat back on the 29th, and I’ll then take it to Fun n Sun hurst to have the motor checked out. Thanks for all the assistance.

Keep us posted on the motor issue, would like to know what the diagnosis is.

Me also

Fun n sun checked it out and said the motor was good to go. They said it was a prop issue more than likely, so I purchased a new tempest 23 pitch 3 blade prop... Took it to the lake and same result, Max rpm still 5000 and should be 5500-6000 on this 200hp Mercury per specs. I gained 2 mph with new prop but same rpm issue. Goes back to shop Thursday for them to go through it in detail I guess. Max mph is 55 and should be getting 65-69 easy. Has a 10 inch jack plate and 55 is not
Loaded down. Any thoughts are appreciated! Thanks

I have a thought, but you won’t like it; because it could involve saturation of the foam in the hull from the damaged spot.

on the motor checkup, I feel like my motor is also having an issue running the full wot. I can change props & pitches and have near the same rpms.

Somethings not adding up here. You went out down 2” in pitch, gained 2mph and yet rpms stayed the same?
Something I haven’t seen mentioned in this thread is have you checked the throttle linkage? Is it opening all the way? Also has the tach been checked and are speeds measured by speedo or gps.

Yes, fun n sun said it’s getting full throttle from hot foot and speeds are from gps.

Boat runs good and idles good, it just won’t go over 5k rpm.

And damage on bottom of boat was properly repaired by classic fiberglass. Ended up being 2200.

That’s good; but how long had it been damaged?

I don’t know, but regardless wouldn’t make a difference with rpm issue. Probably going to replace the coil packs... only thing that hasn’t been done from my understanding. I’ll see what they say this weekend. Thanks

On a side note though, Boat looks much better now! New carpet through out, keel gaurd, and ultrex installed.

What do the spark plugs look like? Do you have one that looks different than all the others, signifying that it may not be firing properly? Surely this has already been checked by Fun N Sun. Just hate to see you throw more parts at the problem without any results. I’ve heard things about bad batteries or bad connections causing weird issues like this. Just throwing stuff out there.

I agree for the most part. Mine has some water in the foam and it causes me some speed loss due to the extra weight. But I also feel like my rpms are stuck, I’m hoping you figure out the cause of yours; because I might be in the same situation.

Are you sure the tach is reading right? When you re-propped, did you go up in pitch or down? If you went up, and your motor is pegged at 5k rpm, then you should of seen a rpm loss, like 4800 or 4600rpm. If you went down you should of seen a increase to 5200 or 5400rpm.

It's possible your motor is running with in specs and your tach just won't go beyond 5k.

Tach issues could be a voltage problem, rectifier may be bad...troubleshooting 101, start at the most simple problem and go from there.

Has new plugs, new batteries, and I went down in prop size from a 25 pitch fury to a 23 pitch tempest. Getting same rpm reading of 5k and I gained 2 mph.

Taking it in today... I feel like it’s sometjing to do with the fuel system somewhere, but Boat runs good and idles well.

Was advised it had some bad fuel injectors... all were replaced... taking her to fork Thursday so we will she how she performs...

Was wondering about the injectors. Almost sounds like they put the wrong ones in when it was rebuilt(if they were changed during rebuild?)? Or were they just all dirty? Thanks for posting back, let us know how she runs

Still has the same damn issue of only getting 4900-5000 rpm a max throttle. Motor runs good, but performance is lacking due to an unknown reason. Taking back to fun n sun Thursday. Will keep this thread updated. I’ve replaced prop as advised and made no difference in rpm out put. Any ideas or thoughts I would appreciate. Thanks

I would consider taking to Charlie’s in Alvarado these guys no there business they can isolate and fix problems. Right now sounds like fixing things to no avail. It gets very expensive when trying to fix and not get right. Just for thought

I had a similar misbehavior on an ‘03 Ficht 225 HO and it sounds like you are running down one cylinder. Mine was a coil issue. Compression was fine on all cylinders and EVDiags didn’t catch it nor where there any active codes/faults. I caught it by replacing all plugs; then, running it under load (on the lake). After returning from the lake, re-examined all plugs and one still looked mint compared to the others.

Mine was lugging out of the hole; on plane RPM slowly crept up with hotfoot fully pressed; wouldn’t reach max RPM or speed. Another symptom was a complete lack of power, for example couldn’t power load on the trailer.

Charlie’s is my next step if fun n sun can get it right this time. I have spent a small fortune already trying to make it right. Will update. I’ll let them know about coil possibility... would hope this has already been checked considering the situation but never know. Thanks!!

This is what i’ve been thinking from the beginning, really sounds like you have a cylinder not firing. I’d take a good look at the plugs again, should be obvious.

GROD, I had the exact same issue as you. It's an easy fix if it's the ignition coil. Look up on YouTube. I also sent you a PM if you want some help with checking it.

Thank you.

Any updates on your motor? Were the coils ever checked?

They said they checked everything, did all possible test, and couldn’t find anything wrong with the the motor and said it runs strong. Still only getting 5k rpm’s and top speed around 54-55 mph. Lot of money thrown down the drain so far chasing the issue.

If they truly checked everything then I’d say your tach is off. Not uncommon

Like was mentioned earlier in this post, this boat should be running close to 70mph. Tach could be a problem, but it ain’t the only problem. You may give Mark Gunter a try, that man has been working on Mercury motors for a LONG time. Sorry for your problems.

Mark is master mercury technician. He will treat you fair not milk it he works out of his house in azle now. 817 626 5693

Thanks!!! Prob gonna have to wait a few months before I do anything else with it. Azle is near me though.

When you’re running WOT and trimmed up, is the spray from the hull behind you or beside you?

I’ll have to take her out again... haven’t paid attention to the spray... if your asking if he bow is getting enough lift probably not. New prop I just put on and had worked at Steve’s gave me 2 more miles an hour and a little better hole shot, but max rpm stil 4900-5k... top speed was 56.2. Tempest 25p 3 Blade... what was recommended for the 200 hp Merc Optimax on the champion forum. Another guy has my exact boat and motor and same jacknplate set up and prop now... he runs 5700-5900 rpm and 71.2 mph.

I didnt see anyone ask if your motor was at the propper setting on your jackplate. Also, if it has waterlogged foam from the fiberglass damage that could be a lot of weight you are carrying around. It is strange that you went down in pitch, gained speed, and had no change in rpms. Did you notice any change in plane speed, acceleration, anything?

Yeah, the waterlogged foam is why I was asking where his spray is at on the sides. Mine had water in it and I’ve been draining it for a year now, picked up 4mph over the year. Since he had damage to the hull, it’s a very real possibility.

I went up in pitch with the tempest 25 (had a new 23 Tempest out of box on it, and when I purchased it it had a 25 Fury) worked at Steve’s Props I Quitman and josh set motor height and jackplate where it needed to be. Seller didn’t tell me about the hull damage when I purchased, and I don’t know how long ago it happened. I had it repaired at classic fiberglass. How would I know if it’s water logged?

Moisture meter, boat body work shop should have one. Thermal vision will work as well. Or redneck it and take a core sample, lol.

Thanks, just trying to rule out everything possible.

I kid you not when I worked for a shop for a while one came in with hard to find runability issues. After months and many techs someone happened to find a bird nest tucked into the cowling out of site. It was causing the issue. I dont remember the exact symptoms but I do remember the bird nest. Go drag your boat across a scale and compare that to manufacture specs on weight for hull motor and allow for fuel load, etc.

I had a customer with an 896 Nitro that wouldn`t run. One day I was moving the boat and heard a strange sound. Walked to the back pushed on the hull and it sounded like a barrel of water. Water was trapped in the hull. Drilled some holes at the bottom sides of the bilge. Must of had 60 gallons of water in it.

Exactly what I had to do to get mine draining, I know I’ve gotten at least 15 gallons out. So I called a shop about pulling the topcap and removing the foam, nobody would even think about giving me an estimate on the cost. Wouldn’t even give me a worst case number, new stringers & etc... Our boats are supposed to have closed cell foam, which isn’t supposed to water log; but the water gets trapped around all the voids in the foam and just ssllloooowwwwwlllllyyyyyyyyyy drains out.


I don’t want to reread the entire thread, are you sure you’re getting full throttle with the hotfoot & throttle cable in the cowling? Seems like it could be out of adjustment since the powerhead was replaced. Would also explain the props not having different WOT rpms.

I talked to Chris at classic fiberglass who did my hull repair, and he stated he didn’t think water could have gotten into the foam. He believes my problem is elsewhere. Gonna meet up with a nice man from here on the forum who offered to assist me free of charge, in couple weeks, and rule out couple other things. I hit 57 mph yesterday with new prop worked at Steve’s in Quitman, but it’s still only getting 4900-5k rpm.

Mines a 2005 champ 198 and the water in mine didn’t get in there from the bottom either. Let’s just say that they must’ve had some quality control issues when it came to using sealant around the jackplate bolts and the screws under the transom stainless steel corner piece.

But hopefully yours is really something else, if you do find something let us know.

Did your mechanic lake test the boat?

Yes, they can’t figure out what’s wrong with it. They say the motor is 100% solid... they think it’s something to do with the prop and set up, but I know it’s not that from elimination and taking it to Steve’s out near lake fork.

Well the new prop worked by josh did help... but still only getting 5100 rpm.., better hole shot for sure and seeing 60 mph. I know every boat and set up are a little different so this may just be all she’s got. Thanks.

if you are only turning 5100 you are still below max rpms

Yeah I know, I just can’t afford to put anymore money into it chasing the problem... I’ll change out rpm gauge or what not to make sure that’s not the issue and I guy from here on the forum is gonna assist me in checking another possible issue.

you can use a dwell meter on the #1 cylinder to confirm rpm's if your unsure of your tach readout

Tachs prob right, mine runs 68 at 5600rpm, so I can see 60mph at 5000rpms.