EGR Excessive Fuel Flow

[Highmarker]

I have a Trailmaster Challenger 300X-E. It has a EFI. I have been trying to figure out why it has a hard time starting and found that it gets flooded with excessive fuel through the EGR. I unhooked the EGR and it runs great. The problem is that with the EGR unhooked, it blows fuel/oil out the tube and all over the engine. So, how do I reduce the excessive fuel flow through the EGR?

 

[Denny]

Got pictures of the system in question? EGR (Exhaust Gas Recirculation) valve should not have oil near it for any reason. Check the oil level in the engine.

 

[Highmarker]

I think that the oil dipstick is not accurate. I filled it with oil until it barely registers on the dipstick. But I think this is too much as the engine specs say 1.1 liters of oil and it takes at least 1.5 liters to register on the dipstick. Too much oil will cause it to pass through the "crankcase recirculation" tube, correct?. I'm not sure it actually has an EGR or not. There is a 1/4" tube running from the top of the crankcase to the intake.

 

[BrownStainRacing]

I think that the oil dipstick is not accurate. I filled it with oil until it barely registers on the dipstick. But I think this is too much as the engine specs say 1.1 liters of oil and it takes at least 1.5 liters to register on the dipstick. Too much oil will cause it to pass through the "crankcase recirculation" tube, correct?. I'm not sure it actually has an EGR or not. There is a 1/4" tube running from the top of the crankcase to the intake.

Get a pic.

That sounds like the crankcase vent tube.

 

[Denny]

And too high of an oil level will make it blow oil!

 

[Snaker]

Does it by chance have an oil cooler?
Often times the additional oil quantity of the cooler plumbing isn't included in the specs.
And it could be a unhealthy engine pushing out oil.

 

[Karttekk]

Check the oil level without screwing the dipstick in, just place it on top of the oil fill port to check it.

 

[Highmarker]

The engine is in a pretty tight spot and my pictures didn't show much. The first picture (300cc Engine 1.jpg) shows the vent tube (on the far left). This is from the top part of the engine that goes to the air intake (downstream of the air filter) that sits on top of the engine toward the far right (not pictured). The second picture (300cc Engine 2.jpg) shows the other side of the engine with the vent tube now shown on the far right. There is a second vent tube that runs from the crankcase to the air intake box (upstream of the air filter). I am getting a lot of fuel/oil blow-by from the vent tube on the far left (300cc Engine 1 picture). I do not get any oil blow-by from the vent tube from the crankcase. I unhooked the vent tube from the far left (300cc Engine 1 picture) and just routed it down (see final picture (20230603_182854.jpg). This makes the engine run smoother, but it blows fuel/oil.

 

[Highmarker]

Check the oil level without screwing the dipstick in, just place it on top of the oil fill port to check it.

By not screwing in the dipstick, this would put the end of the dipstick higher in the oil reservoir and therefore would require more oil to reach the end of the dipstick. I am worried, I would be adding even more oil than what I already have in there which I believe is overfilled already. Does this make sense?

 

[Highmarker]

Does it by chance have an oil cooler?
Often times the additional oil quantity of the cooler plumbing isn't included in the specs.
And it could be a unhealthy engine pushing out oil.

I don't think it has an oil cooler. I don't see one in the parts list, unless it is part of the engine assembly.

 

[Denny]

Does that kart have a lot of hours on it? Been maintained? Overheated? Seized? Sat for a long time? I fear you may have a stuck ring or more?

 

[Highmarker]

Does that kart have a lot of hours on it? Been maintained? Overheated? Seized? Sat for a long time? I fear you may have a stuck ring or more?

It has just over 500 miles on it. I bought it brand new in 2020. I have kept it maintained (ethanol-free gas only, kept oil level up, clean air filter, etc.) When I store it for the winter (up to 6 months), I put fuel stabilizer in it. I guess the best thing to do is check the compression and then put a little oil in on top and run compression test again. If it goes higher, then it's most likely a stuck ring. So, what compression do you think I should be getting for a 300cc engine?

 

[Denny]

Over 100 atleast without knowing cam specs and compression ratio. But if it goes up over 10% I’d be looking at cylinder and rings.