• Welcome to Jetboaters.net!

    We are delighted you have found your way to the best Jet Boaters Forum on the internet! Please consider Signing Up so that you can enjoy all the features and offers on the forum. We have members with boats from all the major manufacturers including Yamaha, Seadoo, Scarab and Chaparral. We don't email you SPAM, and the site is totally non-commercial. So what's to lose? IT IS FREE!

    Membership allows you to ask questions (no matter how mundane), meet up with other jet boaters, see full images (not just thumbnails), browse the member map and qualifies you for members only discounts offered by vendors who run specials for our members only! (It also gets rid of this banner!)

    free hit counter

252 SD RPM wind up

N

nosterka

Well-Known Member
Messages
33
Reaction score
22
Points
47
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
Hey guys, was out last week and had my 252 sd wide open and topped out at 7k on the port engine and about 6700 on the starboard engine. First is this normal to have a difference? I did have the throttles synced. Second I notice boat test mag topped out at 7400 and 43 mph, I was at 40 mph. So should I be revving up to 7400 wide open?
Thanks for the help
 
lowd77

lowd77

Jet Boat Lover
Messages
61
Reaction score
56
Points
67
Location
Minnesota
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
Something doesn't sound right. I get 7600 rpm and hit 46 mph in Minnesota.
 
N

nosterka

Well-Known Member
Messages
33
Reaction score
22
Points
47
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
Thanks for the response, I didn’t think so. I’m going to call the dealer in the morning and talk to them. While on the water I thought it should wind up higher but wasn’t sure so sounds like something might be up. Other than that it seems to run well.
 
HangOutdoors

HangOutdoors

Jetboaters Admiral
Messages
7,226
Reaction score
8,311
Points
472
Location
Royal Oak, MI
Boat Make
Yamaha
Year
2020
Boat Model
AR
Boat Length
21
nosterka said:
Hey guys, was out last week and had my 252 sd wide open and topped out at 7k on the port engine and about 6700 on the starboard engine. First is this normal to have a difference? I did have the throttles synced. Second I notice boat test mag topped out at 7400 and 43 mph, I was at 40 mph. So should I be revving up to 7400 wide open?
Thanks for the help
Click to expand...

Did you check the oil? Maybe dealer over filled it. Our engines are very sensitive to oil level and in can decrease performance and RPM's significantly. Also check your air filters. Oil should be below have, for optimum performance. If you are full up it can and will knock off some decent RPM's. And if it is, I would be wary of the dealer whom did it. Additionally, your spark plugs may have some issues with gap, etc. Mine from the factory were off and when I corrected them I picked up a couple hundred RPM's

Also you will always have different RPM's on your engines at full out, mine are 250-300 different.
 
N

nosterka

Well-Known Member
Messages
33
Reaction score
22
Points
47
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
HangOutdoors said:
Did you check the oil? Maybe dealer over filled it. Our engines are very sensitive to oil level and in can decrease performance and RPM's significantly. Also check your air filters. Oil should be below have, for optimum performance. If you are full up it can and will knock off some decent RPM's. And if it is, I would be wary of the dealer whom did it. Additionally, your spark plugs may have some issues with gap, etc. Mine from the factory were off and when I corrected them I picked up a couple hundred RPM's

Also you will always have different RPM's on your engines at full out, mine are 250-300 different.
Click to expand...
HangOutdoors said:
Did you check the oil? Maybe dealer over filled it. Our engines are very sensitive to oil level and in can decrease performance and RPM's significantly. Also check your air filters. Oil should be below have, for optimum performance. If you are full up it can and will knock off some decent RPM's. And if it is, I would be wary of the dealer whom did it. Additionally, your spark plugs may have some issues with gap, etc. Mine from the factory were off and when I corrected them I picked up a couple hundred RPM's

Also you will always have different RPM's on your engines at full out, mine are 250-300 different.
Click to expand...
I did not check the oil but will look at that. This might be a dumb question but going to ask anyways....while on the trailer as long as it’s level should that be good to get an accurate reading? Do you happen to remember what the gap tolerance should be on the plugs? I’m guessing it’s about 250-300 rpm difference at wot so that’s good to know it’s normal. Thank you for the help so I can see where to start. My local dealer is about 1.5 hrs away and then 5-6 hours for the next so I’m hoping the closer one is decent. Thank you again.
 
Sean R

Sean R

Jetboaters Captain
Messages
720
Reaction score
888
Points
207
Location
Acworth GA
Boat Make
Yamaha
Year
2020
Boat Model
212S
Boat Length
21
Mine are also, port 7600 stbd 7300. that is normal? I was going to swap impellers to see if lower rpms switched engs. I'll also check oil and airfilter.
 
HangOutdoors

HangOutdoors

Jetboaters Admiral
Messages
7,226
Reaction score
8,311
Points
472
Location
Royal Oak, MI
Boat Make
Yamaha
Year
2020
Boat Model
AR
Boat Length
21
My engine's run at 7700 and 7500/7400 WOT. Yes your engines will run add different RPM's wide open throttle. That is working as intended. There is a thread around here discussing that and why, I just can't seem to find it at the moment.

Yes check oil level. Midway between L and Half way. Under a half. If you are full or overfilled, you may have saturated your air filter. You can always pull your air filters and make a run with and without them to see if there is a difference.
 
Sean R

Sean R

Jetboaters Captain
Messages
720
Reaction score
888
Points
207
Location
Acworth GA
Boat Make
Yamaha
Year
2020
Boat Model
212S
Boat Length
21
I am pretty sure my oil level is good, I do the mantaince. I put in the same amount I pull out, but worth checking, again. Shit I check the oil almost every outing.I haven't checked the airfilter since February, also worth a check.
 
HangOutdoors

HangOutdoors

Jetboaters Admiral
Messages
7,226
Reaction score
8,311
Points
472
Location
Royal Oak, MI
Boat Make
Yamaha
Year
2020
Boat Model
AR
Boat Length
21
just throwing some things around, hoping it is an easy resolution.
 
Sean R

Sean R

Jetboaters Captain
Messages
720
Reaction score
888
Points
207
Location
Acworth GA
Boat Make
Yamaha
Year
2020
Boat Model
212S
Boat Length
21
Not to change the subject BUT I just got the Ark 750 trailor jack cant wait to install. Your previous threads talked me into it 😎
 
N

nosterka

Well-Known Member
Messages
33
Reaction score
22
Points
47
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
Just wanted to add the boat only has 7hrs on it and this was the first time I really went wot, was not comfortable with prior conditions to attempt. If the boat had too little or too much oil that wound be from the factory and something missed on the PDI, correct? I plan to call and talk to the dealer as I was going to have them perform the 10hr service, would do it myself but I’m not sure I would have the time right now.
 
N

nosterka

Well-Known Member
Messages
33
Reaction score
22
Points
47
Boat Make
Yamaha
Year
2021
Boat Model
252SD
Boat Length
25
Dealer said they would check it out but said it could possibly be elevation causing the low RPM as we are at around 4,000 feet. Could this be a possibility?
 
Sean R

Sean R

Jetboaters Captain
Messages
720
Reaction score
888
Points
207
Location
Acworth GA
Boat Make
Yamaha
Year
2020
Boat Model
212S
Boat Length
21
It could, there are a few threads on here regarding poor performance at high elivation and the modes to improve.
 
You must log in or register to reply here.
Top