Has anyone heard od a jet power

[Pstuart]

I have a 1987 mercury 115 jet power 6 cyl. I cant find any information about it anywhere. It says jet power on the cowl. Any information about this engine would be greatly appreciated. Thanks

 

[ondarvr]

The motor is no different than a normal 115 from that year, only it has a jet pump on it, the pumps are made by Specialty Manufacturing Outboard Jets.

 

[Pstuart]

Thank you. I was told it was a 150 power head but was down rated to 115 becayse of the jet. The guy that told me didnt seem too sure tho.

 

[ondarvr]

It depends, they came both ways. Merc made motors that came as jets and they were rated for use with the jet, plus dealers installed jets themselves, or the customer did, these would have the prop related HP on them. Right around that time there were 6 cylinder Mercs around that HP range.

The 150 prop is rated at 105 as a jet.

 

[Pstuart]

Is there any way to tell the difference. It makes a big difference in impeller sizes. Thanks

 

[ondarvr]

The # off the motor will tell you everything you need to know.

 

[Pstuart]

Thanks again for all the help. I will try to decipher the numbers again. It is hard to find anything about a jet power.

 

[ondarvr]

You don't need to figure anything out about the serial # on the motor, just match it up on this site when you're doing a search for parts.

 

[Chris1956]

OK, An inline six from 1987 had a max of 115HP, rated at the prop. When a jet unit was substituted fro the prop, the power was lessened by 30% or so. The power difference is still debated.

Mercury and other manufacturers dreamed up the "Jet Power" label to tell the consumers. I have never heard that Jet Power was a rating with actual credentials.

 

[Alumarine]

Just in case there's any confusion the powerhead itself is not derated when compared to a prop drive.
It's the horsepower at the drive end that is being referred to. The jet is not as efficient.
A 115 is a 115. Go by the serial no. for parts.

 

[Pstuart]

Thanks for all of the help and information. Any tips on keeping this engine running? I have read about plugging the hose and removing the vent jet on the carbs. Anything else? Thanks again

 

[Chris1956]

There is debate on keeping or disabling the backdrag carb system. I left mine on and had no issue.

​The best way to keep the motor running well is to use it regularly, keep the fuel fresh, perform maintenance on the water pump and keep her greased.

 

[Faztbullet]

Funny I haven't found a kit for any Inline crossflows offered....You sure this isn't a V6?????
http://outboardjets.com/download/jet_drive_kits/Mercury-Blue-Binder-2016.pdf

 

[ondarvr]

Inline jets were common, I have a pump for one sitting in my shop, they may not offer them any longer though.