Suzuki DT115 Oil Flow

[Knightgang]

I have a 1985 Suzuki DT115. I recently found that there was a partial blockage in the oil reservoir pick-up tube. Since cleaning that out, I have noticed that the engine seems to smoke more. I put about 5 hours on it since, running at cruising speed and idle thru many no wake zones. The engine began running real rough, and cutting up. I replaced the plugs, but now it seems that it does not want to start unless you give it a little raw gas straight into the #1 cylinder (thru the plug hole). One it cranks up, it seems fine.<br /><br />Is it possible that the oil mixture is now to rich and is causing the plugs not to fouls quickly and not fire well until actually cranked up.<br /><br />ALso, what is the best way to measure the oil flow without buying that special tool from Suzuki?<br /><br />Thanks guys?<br />Knightgang

 

[jim dozier]

Re: Suzuki DT115 Oil Flow

The Clymer manual has a table in it for oil pump test specs. I will try to look it up when I get home. Buy a large syringe (without the needle) that they measure baby medicine with at the drugstore and disconnect the oil tank and run a oil hose directly to the syringe with the syringe plunger out. Just hang it somewhere. There is a pump spec for max and min (the oil pump is connected to the throttle which is disconnected and held manually at max or min) at specific rpms. Just run the engine with the syringe full at the specified rpm and measure the amount of oil it uses over the time specified in the table.

 

[Knightgang]

Re: Suzuki DT115 Oil Flow

The syringe for the baby medice is a good idea. I have the manual with the tables, I was just wondering about a good way to measure. Also, I wondered last night if a large oil line from the tank to the pump would cause it to use more oil. Seems to me based on physics and mechanical basics that it would. The oil line I installed was 1/4 in inside diameter. I pickup up the proper 5X8 hose today and will try that. <br /><br />Is there any way to adjust the oil flow other that with the throttle rod. The Clymer manual says that if the oil pump does not produce flow within the specs, you need to replace the pump. Seems to me you should be able to turn a screw and lean it out a little.

 

[DjPro]

Re: Suzuki DT115 Oil Flow

Plugs are designed to fire at much higher volts and will call for more juice if needed. I.E. too rich. In my opinion, you would be hard pressed to run too rich to foul the plugs. Something else is going on. Possibly electrical. CHeck the oil sensor..

 

[jim dozier]

Re: Suzuki DT115 Oil Flow

You should use the Suzuki spec hose. There is a different diameter from the tank to the pump than the pump to the intake manifold. I'm no expert but I think the whole system is calibrated to the tubes and orifices and check valves in the line. The only way to adjust the output is the throttle linkage. You can back the pump max down a little but I wouldn't do that until you confirm the pump output is over spec. Fix the hose diameter before you measure it.

 

[Knightgang]

Re: Suzuki DT115 Oil Flow

I think the diameter of the inlet hose to the tank may have been the problem. I talked ot a Suzuki shop, and they gave me the demensions of the hose. It is a 5mm X 8mm. There is a big difference between the 1/4 in diameter of my replacement hose, and the 5mm of the proper hose. Picked up a hose from a local outboard shop that is the speified demensions. I will let you guys know what happens as soon as I get it installed.<br /><br />My engine does not have an oil flow sensor, just an oil level sensor in the tank. It is possible that the plugs that fouled were already worn enough that the extra oil being burned pushed them over the edge.