Suzuki DT 150 will not go above 2000 RPM

[ncbrew]

My son has twin 1998 Suzuki DT 150 HP engines. The port engine will not run above 2000 RPM under load. In the driveway it will rev up normally. When he puts it in the water
the load of the water won't let it rev up. The compression test shown 82 lbs in each cylinder.
I would like a list of things to look for. I wish I knew everything he has tried but I don't know. I can find out tomorrow. 2 different boat shops have worked on this problem to no avail.

NCBrew
dadinnc@gmail.com

 

[99yam40]

Re: Suzuki DT 150 will not go above 2000 RPM

I am not that familiar with the Dt150's but 82 sounds kind of low for any motor.
Is that on all cylinders on both motors?
HAVE YOU TRIED A DIFFERENT GAUGE?

Do you have a manual for your troubleshooting of that model motor?
I believe that is about the year model that a friend had, but he sold the boat with twins, he still has the manual and some spare parts I think. If you are interested PM me and I will check to see for sure what he still has.

2000 is usually the RPM limit of the safe mode, so I would make sure the alarm system is functioning properly, as that should be going off(sounding) along with RPM reduction if the safe mode is coming in

 

[ncbrew]

Re: Suzuki DT 150 will not go above 2000 RPM

He has been to 2 different dealers and they both have manuals. trouble is, they cannot figure out what is wrong with the engine. It used to run fine.
I am hoping there is an expert on the Suzuki DT 150.

 

[capecodmfg]

Re: Suzuki DT 150 will not go above 2000 RPM

I'm having some similar issues in my '96 DT140... This raises two questions: 1) How does "safe mode" work? I suspect it kicks out one of cylinders? 2) Could a failing cooling water sensor cause the motor to go into safe mode?

Best of luck!

 

[gonnabe]

Re: Suzuki DT 150 will not go above 2000 RPM

Reviving this thread because I have the same issue.
Dealer has no clue and just kept changing parts at my frineds expense and still hasn't resloved the problem. (They even changed the VST saying it was creating "electrylosis" and degrading the needle valve).

He's asked me to take a look (I'm not a mechanic but have managed to keep my boats running for the past twenty plus years).
)

He has the shop manual, however it is somewhat confusing as this motor (2000 DT 150) is fuel injected and the manual states the carbs need to be removed and cleaned. Manual does cover the 225 EFI- should I use that info for the 150 fuel system, or do I need a different manual.

Thnaks in advance for the help