[trashtruck]

went to fill up my 82 yesterday with gas and when i was almost home the bike started to act like it was starving for fuel. well sure enough some idiot biker forgot to turn on the petcock, running the carbs dry. after i got through kicking myself, i turned the gas on and went to restart it. heard one cyl catch then the next and so on. the oil light never went out. i was only a couple of hundred feet from home so i rode it into the driveway and shut it off. when i went to re start it, it makes a thumping noise near the rear of the motor and the oil light still wont go out. hooked up one of those aftermarket oil guages and cant get a reading so no oil pressure. removed the oil and filter and didnt see anything unusual. removed the oil strainer and it was clean. what do i need to look for next?

 

[JerryH]

A thumping noise and no oil pressure is not good. Was the oil level ok? If it were a cartridge type Fram filter, I'd have a pretty good idea what the problem was, but that wouldn't be the case with the element type stock filter. There are 2 oil pumps, and both can be removed without splitting the cases. Seems like I remember one of them being chain driven. I think a chain is a lot more likely to fail than an oil pump, and if I remember right, the chain driven one is at the rear of the motor.

 

[glhonda]

The drive gear for both pumps is at the rear scavenging pump. They are connected by a drive shaft, so if the rear has failed, the front probably isn't spinning either.
There is a bolt that holds the gear to the scavenging pump. More likely the bolt, than the chain.
To break a chain, I would assume a catastrophic event like pump seizure. You would have heard that.
If the just scavenging pump isn't working, the oil cannot make it back to main sump, so you'd have pretty much the same result.

 

[trashtruck]

thanks jerry. is there a way to check the chain for the pump without splitting the engine? i'm not scared to pull it, had to last year for the stator but i'm a little nervous about having to break it open.

 

[Ken Bergen]

Seems like I remember one of them being chain driven. I think a chain is a lot more likely to fail than an oil pump, and if I remember right, the chain driven one is at the rear of the motor.

Jerry, your rememberer like mine is broken.:raspberry:
Yes the oil pumps are chain driven but there's only one chain and it drives both oil pumps plus the water pump.

The simplest test is to remove water pump cover. If the water pump turns by hand you have a problem, if the water pump doesn't turn when you crank the engine you have a problem.

 

[glhonda]

The simplest test is to remove water pump cover. If the water pump turns by hand you have a problem, if the water pump doesn't turn when you crank the engine you have a problem.

He's already pulled a pressure test and has no oil pressure. If the sump is full, it really doesn't matter if the w/pump spins or not. He's still has a problem....

 

[Ken Bergen]

He's already pulled a pressure test and has no oil pressure. If the sump is full, it really doesn't matter if the w/pump spins or not. He's still has a problem....

Yes I know but is the problem in the rear chain drive or the pump?
If he wants to fix it he could save many hours by narrowing it down to the front or back of the engine.

 

[trashtruck]

ok, to answer a few more questions before this yes the bike was running good and had plenty of oil. just drained the radiator and pulled the smaller cover off the water pump and verified that it is not turning. i guess the next step is to pull the the motor and take the rear cover off?

 

[Hobie1]

There is a screen on the fuel pump side of the motor that is rarely discussed but you need to check it for blockage. It's towards the front of the motor and has four bolts holding the cover plate. FWIW.
Hobie

 

[Ken Bergen]

pulled the smaller cover off the water pump and verified that it is not turning. i guess the next step is to pull the the motor and take the rear cover off?

The pump doesn't turn by hand or it doesn't turn with the engine?

 

[trashtruck]

waterpump not turning with the engine

 

[Ken Bergen]

waterpump not turning with the engine

I hope running with out oil pressure didn't do to much damage but in your boat I'd be looking for a new/used engine.

 

[DaveO430]

Whatever it is, chain broken or just the screw that holds the sprocket came out it is an engine out job. You have to remove the rear cover to get to it.

 

[trashtruck]

update: problem found and fixed. the bolt did come out of the rear pump drive gear. not sure exactly what kind of damage was done but it now runs and i have pressure. and yes it does take 8 hrs to pull a motor and put it back in. thanks all for your help.