• 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

Does anyone have detailed info on the various MR1 versions? (HP and Impeller questions)

Bruce

Jetboaters Fleet Admiral 1*
Staff member
Administrator
Messages
13,385
Reaction score
13,502
Points
857
Location
Royal, AR
Boat Make
Yamaha
Year
2007
Boat Model
SX
Boat Length
23
According to CARB numbers;

In 2008 the 1052cc 8YMXM1.054HA used in personal watercraft was rated at 104.5 KW (140 BHP).

In 2007 the 1052cc 7YMXM1.054GA used in personal watercraft and jet boats was rated at 104.5 KW (140 BHP)

You can view the certifications at http://www.arb.ca.gov/msprog/offroad/cert/cert_mfr.php

For the 2007 to 2011 period the EPA listed two 1052 cc engine families 4YMXM1.054GA and 8YMXM1.054HA at 99.8 KW (134 BHP) and 103 KW (138 BHP) 2007-2011 MYs (Zip)

The 2006 SX230 owners manual specifies the non-HO as having 998 cc engines producing 140 HP @ 10,000 RPM and the HO as having 1052 cc engines producing 160 HP @ 10,000 RPM. The 2007 and 2008 SX230 owners manuals document the same 160 HP engines. The 2009 manual does not document horsepower.

The 2008 SX230 owners manual specifies it as having 1052 cc engines producing 110 HP @ 8,000 RPM.

Interestingly the 2006 SX230 manual specifies the non-HO prop pitch as Port 16.3° / Starboard 17.3° and the HO prop pitch as Port 18.1° / Starboard 15.1°.

The 2007 & 2008 230 manuals specify the all-HO SX/SR prop pitch as Port 16.3° / Starboard 17.3° and the all-HO AR prop pitch as Port 18.1° / Starboard 15.1°.

The 2009 230 manuals specify the prop pitch for both the SX, AR, Limited and Limited S as Port 18.1° / Starboard 15.1°.

Checking parts diagrams I did not find differing impeller parts for the SX and AR models. Part number 6P6-R1321-10-00 was specified for everything from a 2005 HO to a 2009 while 68N-R1321-10-00 was specified for 2003 to 2006 models with the 998 cc non-HO engines. I wonder if the pitches quoted in the manual are misprints or if 2007 and 2008 SX230s really received lower pitched impellers. I may have to pull my impellers again and check the part number.

The 2008 SX210 manual specifies as single prop pitch of 16.5° and the parts diagrams only specify an impeller for the starboard side.

@buckbuck noticed that his 2008 212X engines have stickers that state "Advertised Power: 104.5 KW" which is 140 HP my 2007 SX230 has the same stickers. My stickers specify the engine as belonging to the 7YMXM1.054GA family. My engine serial numbers are 1016279 starboard and 1016280 port with a model number of JF110CN. I wonder what the stickers on 2008 and 2009 models say?

Does anyone know what the difference is between the 2007 and before GA engine family and the HA engine family in 2008 and later?

My 2007 SX230 tops out around 46 mph. I have read of several others that top out at 46.

@Speedling, do you have any thoughts on the pitch difference?

Almost in the words of Forest Gump, that is all I know about that. I hope that others will have info to help us better understand the mystery of the MR1 engine.
 
Last edited:
I hope I'll get my boat back from the fiberglass shop tomorrow or tuesday... I'll crawl in and try to find the stickers on the motors... where would I find them?
 
I can't check the decal as the boat is wrapped up for the winter, but the big decal on the back of the boat said "320HP" (I removed them)
Our 2008 AR230HO hit a max speed of 49.2 this past summer. One engine was a couple RPM lower, we think probably due to the impeller being dinged up by rocks(the previous owner enjoyed the sandbars)

I had them both refurbished over the winter so I hope to break 50MPH now.
 
I hope I'll get my boat back from the fiberglass shop tomorrow or tuesday... I'll crawl in and try to find the stickers on the motors... where would I find them?

Mine are under the air filter on the starboard side.
 
I am busy at the moment but had a chance to take a couple pictures quick. The engine hatch says one thing and the engine something different!
20160228_142100.jpg 20160228_142304.jpg
 
Also, it is hard to see but engine ends with ga.
20160228_142132.jpg
 
Here's mine off my 2008 212X. Not a 230 but I think it is the same engine.

engine kw tag.jpg
 
Last edited:
The plot thickens. Speedling and I have same year, same 212 models, same engine family, but his is CA rated on the hatch but engine is same as mine.
:)It would have broke my heart to reveal to him he has significantly less hp than me.:)
 
Now wait a minute. It is not being said but it can be derived from the above information that yamaha may have been falsely advertising the motor power, OR, has been feeding incorrect information to the epa for those stickers etc.

I am willing to bet that no one finds a sticker stating more than the 104.5kw on the engine unless it is a 1.8 but I don't believe those state power.
Also, my impellers were more like 14/18 on both when I pulled them off but we're mangled badly to where one blade could read 24 degrees and another at 18.
In any case, putting the 14/20 Solas on there sees similar rpm as the fx160 ski so I have to assume that it is the same. An engine from the fx140 would mean my 14/20 is way overkill and should be more like 12/18 at best.

It COULD be that Yamaha under rated the engines but that would be considerable and strange that they would advertise it as one thing then tell epa something else.
 
Ya, somethings a bit sketchy about that.
Just a note Bruce, I do not have a 230 model.

My port impeller is 6P600 with 18.1° pitch.
My starboard impeller is 6P610 with 15.1° pitch.
Both have left hand threads.
 
Ya, somethings a bit sketchy about that.
Just a note Bruce, I do not have a 230 model.

My port impeller is 6P600 with 18.1° pitch.
My starboard impeller is 6P610 with 15.1° pitch.
Both have left hand threads.

Thanks, corrected, not sure how I messed up the model info since I know your boat!
 
Just checked my oem impellers and I match @buckbuck
 
Just for reference, since I have a 2006 SX210 (wimpy motors). Port impeller 6S802. Starboard impeller 6S810. Engine family 6YMXM1.054GA. Advertised power 75.0 kW. Displacement 1052cm3. My pumps are currently out so easy to read.
 
This is the sticker on my engine compartment and the very low emissions two star CARB sticker. Do you have similar carb emission stickers?
 

Attachments

  • image.jpeg
    image.jpeg
    1.9 MB · Views: 58
  • image.jpeg
    image.jpeg
    594.2 KB · Views: 71
Yes, but it references 2006 EPA of course. Two stars, very low emissions.
image.jpeg
 
I have no very low emission stickers anywhere that I know of.
You don't have carbs do ya? I have random stickers missing anyways... Of course, the one on the swim platform is still there :)
 
I have no very low emission stickers anywhere that I know of.
You don't have carbs do ya? I have random stickers missing anyways... Of course, the one on the swim platform is still there :)

CARB is California Air Resources Board. I know that California 240s are tuned down but I have never confirmed that for 230s. Mine was originally a Florida boat.
 
Back
Top