LS 2000 Yamaha Oil Pump output

[DavidLS2000]

Hello fellow Jet boat owners.

I have a 1999 LS 2000 with 2 135 hp engines. The boat was a real mess and I have been trying to bring it back. After removing 9 year old gasoline, I removed the oil pump coupler and put in premix into it. I got it running and have had it out on Lake Erie 5 times. It is a fun boat. A number of things still need attention.
I replaced the oil lines with ether polyurethane hose and ss wire ties. Since the boat had sat for 9 years I am leery of the oil pump output. I have looked all over for answers and have not exactly found what I want. I am looking for the oil output of one carb/cylinder line at 2 minutes at 2000rpm? 3000rpm?
4000rpm? 5000rpm? not touching the oil pump pulley other than having the throttle opening it.

Regards,
David

 

[Bruce]

Do you have access to a service manual? I wonder if the info may be in there?

 

[DavidLS2000]

Do you have access to a service manual? I wonder if the info may be in there?

Hi Bruce,
I do have a service manual and this important information is no where to be found. Oil is important

Regards,
David

 

[Bruce]

@Speedling, have you ever seen this info?

 

[Speedling]

I have never seen that info nor have i seen anyone ask that question.
If in doubt i don't recall that pump being very expensive. It is the same pump that gets used on the snow skis as well as the jet skis and maybe even the older 4 wheelers. Very universal unit.

If you are running premix you could simply take the three hoses off and run it for a minute or two letting the oil pump into cups and measure the levels. This should give you a measurement but with no guidline it gets you no where closer to an answer, i agree.
It is also a variable pump so that the ratio is actualy leaner on the top end of rpm than on the bottom, or so i recall.
I will say that if you are at idle or just idle and forward, you will be smoking a lot in no time. If not.... throw oil in your fuel and change the pump out.

 

[DavidLS2000]

I have never seen that info nor have i seen anyone ask that question.
If in doubt i don't recall that pump being very expensive. It is the same pump that gets used on the snow skis as well as the jet skis and maybe even the older 4 wheelers. Very universal unit.

If you are running premix you could simply take the three hoses off and run it for a minute or two letting the oil pump into cups and measure the levels. This should give you a measurement but with no guidline it gets you no where closer to an answer, i agree.
It is also a variable pump so that the ratio is actualy leaner on the top end of rpm than on the bottom, or so i recall.
I will say that if you are at idle or just idle and forward, you will be smoking a lot in no time. If not.... throw oil in your fuel and change the pump out.

Hi Speedling,
Thank You! Yes, the pumps new are $300.00@ new, buy used for $80.00. Used pumps do not say they are better than mine, nor do new pumps. After installing fuel gauge, fuel sending unit, horn, new clean out plug, and new fuel lines and filters, I would like to make sure my oil pumps are to factory specs. I am running premix right now and have tested oil outputs at various times and rpm and have output measurements however I do not have anything to compare my outputs. That is the reason for my post. The oil pumps on the LS are variable, the more rpms, the more oil is used.
Regards,
David

​

 

[Speedling]

@DavidLS2000 the best I could come up with was people talking about a dirtbike pump. Idle 1cc of oil per 200 rpm. 9.3 cc at WOT per 200 revolutions. Now, I don't know if that is per cylinder or total, but now we have to figure out how to crank that bad boy 200 times exact, lol!

Something like that will at least let you know if it's working.
Honestly, if it's pumping oil, I wouldn't worry about it because it's a very reliable part of the system.
Another thing you could do is run small separate tanks on each motor and see if one hardly drains and the other one drains quickly. Obviously there will be a little variance in engine rpms and usage etc but they should be relatively similar. You're on your own on how to rig that up, but it would be a sure fire way to know if one is faulty!

 

[DavidLS2000]

@DavidLS2000 the best I could come up with was people talking about a dirtbike pump. Idle 1cc of oil per 200 rpm. 9.3 cc at WOT per 200 revolutions. Now, I don't know if that is per cylinder or total, but now we have to figure out how to crank that bad boy 200 times exact, lol!

Something like that will at least let you know if it's working.
Honestly, if it's pumping oil, I wouldn't worry about it because it's a very reliable part of the system.
Another thing you could do is run small separate tanks on each motor and see if one hardly drains and the other one drains quickly. Obviously there will be a little variance in engine rpms and usage etc but they should be relatively similar. You're on your own on how to rig that up, but it would be a sure fire way to know if one is faulty!

Hi Speedling,
Thank you! I have done all those tests on my oil pumps and the drill press test. They do pump. The problem is the Yamaha factory output for the pump at various RPMs. and time for each carb/cylinder on LS 2000's oil pumps. What should the output be? I have looked all over for answers and have not exactly found what I want. I am looking for the oil output of one carb/cylinder line for a specific time at 2000rpm? 3000rpm? 4000rpm? 5000rpm? not touching the oil pump pulley other than having the throttle opening it.

 

[Speedling]

Well, if you have measurements at different rpms already, perhaps we can figure out fuel consumption and figure out the ratio?
Honestly if they are both working i bet they are doing just fine.

 

[DavidLS2000]

Well, if you have measurements at different rpms already, perhaps we can figure out fuel consumption and figure out the ratio?
Honestly if they are both working i bet they are doing just fine.

Hi Speedling,
I don't doubt my pumps are working, they are. I want the factory specs to compare with what I have. I was hoping someone would have this information. This information should be in the service manual like Kawasaki has on their 1200cc engine. I have sent letters to Yamaha in GA and to CA requesting oil pump output.
Regards,
David

 

[Kenneth Johnson]

How can you stop the idle and up smoking? What is the fuel ratio? 50/1?

 

[Bruce]

How can you stop the idle and up smoking? What is the fuel ratio? 50/1?

The factory oil injection system varied the ratio based on RPM. If you have switched to premix the smoke will be strong.

 

[Kenneth Johnson]

Many thanks, Maybe I should consider reinstalling a pump.

 

[Kenneth Johnson]

Hey David, Did the new pumps reduce the smoke?

 

[the MfM]

The pump will vary output...it has a range of something like 100:1 at idle to 32:1 at full throttle.

So if you are pre mixing at 50:1 you are burning twice as much oil at idle. So yes there will be more smoke when pre mixing at idle. Though if you go from full throttle to idle there may be a slight delay before you see the reduced smoke.

There are other advantages to using injection vs pre mix as well. Just need to keep an eye on the oil lines.