Mcx nytro burning oil, can see it smoking out the exhaust. I have a few questions.

[Tuesday]

I will give as many details as I can to help diagnosis this problem.

Road 3 days in revy, no problems. Never had any major roll overs or upside down events.


When I got home from riding I took the sled off the deck the other day I could smell oil burning. I thought it was just from coming off the ramp or a small drip that was burning off. I put it in the heated garage and let everything thaw out. I hooked up the battery to the solar panel like I always do to trickle charge the battery. I have no idea if this is somehow related but it got me thinking. I went to take the sled for a rip today the battery was stone flat dead. There must have been a leak some how with the panel.

Anyway charged up the sled for about 30 min then went for a rip. I could smell oil burning in the exhaust every so often. When i stopped it was smoking burning oil fumes out the exhaust for a very long time....10 min?


Let the sled sit for about 3 hours with charger on, fired up the sled in the garage let it get fairly warm. It was too late to go for a ride but regardless it was not smoking? I will let it charge all night and give it a test run tomorrow.

I dont think the battery has anything to do with it but who knows.

No codes on display.

No kinks in oil lines.

Oil is fresh and topped up.

no oil leaks anywhere visible.

Mcx nytro 270kit approx 7300km on it.

I noticed there was 3 oil hoses. 1 on brake side(feed hose?) and 1 heading down throttle side (return hoses?)

Can i unhook the hoses and see what oil flow looks like?

Is this symptom common with oil pump failure or shear pin failure?

I will attach a pic

 

[Tuesday]

 

[icr]

If there's oil in your charge tube it's a compressor seal.

 

[Tuesday]

If there's oil in your charge tube it's a compressor seal.

I have not pulled the charge tube yet.

Just brain storming before i start tearing things apart.

 

[NM]

If it was really cold when you started it then it could have sheared the pin in the pump. Pull the cover off the pump and check it out. If the oil can't return it will blow past the seals and out the exhaust.

 

[Tuesday]

If it was really cold when you started it then it could have sheared the pin in the pump. Pull the cover off the pump and check it out. If the oil can't return it will blow past the seals and out the exhaust.

-15c?

Good thinking I will check it out.

 

[BOOSTD]

Im willing to bet shear pin. Inspect like neil said and if its broke, replace it and go ride, its that easy, turbo will be fine.

 

[Tuesday]

Never changed the shear pin. I assume i dont have to pull the motor? Is there a step by step or picture of whats required?

 

[kimoaj]

I would also check the sheerpin.
You will have to remove the oiltank to get access to the oil pump, remove the four screws from the oilpump cover and replace them with some much longer screws (btw they are 5mm M5 regular threads), then put a pry bar between them to loosen the pump. They will probably bend but that doesnt matter as long as you get it loosened.

If your sheerpin is broken then I would recommend you to remove the stator cover to search/remove the broken bits, you don't want them in your motor.

A new sheerpin can be made of a 3mm drill bit, (ofcourse use the part that goes into the drill) , just cut it to the right length and it will be ok. (Erik Marklund told me this, he is the founder of MCXpress).


Just so you know, the turbo oilpump sucks oil FROM the turbo, not TO the turbo.

Your oil lines are routed differently then mine but I do think that the left one on the picture is the feed line from the engine, the one in the middle is the return line that goes to the pump and the one to the right is the vent line that goes to the MCX plenum.

A blocked vent line can also make it smoke.

Make sure your turbo vent line is clear and that your engine crankcase breather is not blocked. I dont know if its for real but some say that if your crankcase breather is blocked, pressure can build up inside the engine and oil can be pressed passed the pistonrings and make the engine smoke.
However since this is a drysump engine I am not sure if it really occurs to this engine.

Wellwell might not be any help in this but I felt like writing

 

[Tuesday]

Did some testing in the daylight.

Fired up and let sled warm, very minimal oil smell. Went for a small ride maybe 3 min. Faint smell of oil burning. After about 8 min I put it back in the shop could smell a bit of oil burning.

Turned the sled off and for approx 5 min oil smelling smoke kept coming out the exhaust. See video.

 

[Tuesday]

 

[BigFish BC]

just pull the cover off & you should be able to see the peices there the shearpin in this pic

 

[Tuesday]

Made it to here now what? Not sure what the next step is to find the shear pin?

 

[Coxy]

Fish that outside pump ring our with a magnet, and see if the inside gear/pin is engaged to the crank, or spins freely. Picture makes the gears look rusty? Maybe I'm just seeing things

 

[Tuesday]

The 5 star piece comes out with a magnet?
I think its just the lighting, its not rusty.

If I were to crank the motor for a second it should spin? If it doesnt spin the shear pin is gone right?

I will give it a test after the super bowl!

 

[Sleds R Fun]

Oil suction pump

This might help

 

[Tuesday]

This might help

I also have that install guide but its so vague. I am not sure what the next step is.

 

[Bubbles]

i think he means the inside pin on the gear should come out if sheared.

 

[summitboy]

I would just unscrew the oil pump and look at the pin if there are a lot of miles on the kit. I have had one that wore down to nothing and one that broke. If you do end up taking out the housing they sometimes can be tight. Use other bolts in the holes and a screw driver to turn the the pump out of the case. I used the MCX bolts once and bent a couple of them. It's easy to do.

Are you seeing a steady stream of smoke out the turbo ? If so its the shear pin most likely.

 

[Tuesday]

I would just unscrew the oil pump and look at the pin if there are a lot of miles on the kit. I have had one that wore down to nothing and one that broke. If you do end up taking out the housing they sometimes can be tight. Use other bolts in the holes and a screw driver to turn the the pump out of the case. I used the MCX bolts once and bent a couple of them. It's easy to do.

Are you seeing a steady stream of smoke out the turbo ? If so its the shear pin most likely.

When i am riding or idling you can smell it but not see it. When I shut it off there is a steady stream you can sort of see it in the above video.

So that pump just turns out? Counter clockwise? Never had the pump off, sorry for the noob questions.