2015 RT SM6 Burning Oil - anyone done a rebuild? Or should I sell as is?

[wcntech]

I have a 2015 Spyder RTS SM6 with 18,300 miles that is burning oil. Pulled all the plastic and frunk and then pulled the airbox. Checked spark plugs and middle cylinder plug is darker than the outer two cylinders. Checked compression, the two outer are around 175, middle is around 140. Sounds like rings in the middle cylinder, yes?

Anyway, looking for advice from here. Everything else on the RT is is great condition.

Thanks for any help!
AJ

[BoatFixx]

Do a wet compression test in the low cylinder. If compression increases it is most likely rings.
If not then look to valves.

Addenda: Valve seals?

[BajaRon]

Very unusual for an engine with those miles. Something is definitely up. BoatFixx gives good advice. Do that and you should be on your way to an answer. I'm betting cylinder issues as bad valves are not usually going to burn oil. Bad valve seals will. But that won't give you low compression. Could be a combination of both. But more likely, a cylinder issue. I wonder if it has been overheated. The center cylinder will take a beating in an overheat scenario.

Your findings will be interesting.

[wcntech]

Going to try something maybe considered unconventional. I have been watching several videos on piston soaks with Berryman B-12 Chemtool with pretty good success. Going to try that. At this point, I don't feel like I have anything to lose. The theory behind the soak is to loosen up gummed up rings and remove varnish or sludge that might be in the rings to help them seal.

Will post results maybe next week with what I did. It may take a month or two to get longer term results to see if the oil burn is reduced. It may take a couple of treatments, but if it saves from tearing down the engine at the stealership, then great! If not, I'm out my time (not worth much) and about $20.

Stay tuned!

Thanks for your

[PMK]

My opinion, for the condition you are experiencing at this time, is to assume it could be any number of concerns.

Therefore, before tearing it apart, or adding magic juice products, accomplish a cylinder leak down test. Properly done, the escaping air will give a very good indication on how to proceed.

Measure each cylinders leak down with piston at top center on compression event. With pressure applied, you can remove the dipstick and listen to verify ring condition, or listen at air filter or exhaust outlet. These three sources of leaking air can help determine where to focus efforts.

Accomplish the test on all three cylinders, this will give a basis to compare between cylinders.

[BajaRon]

Get a probe camera and look inside the cylinder. That might give you an indication as to what exactly is causing the problem. If it is a broken ring it will scar the cylinder wall. Chemtool isn't going to fix that.

[PMK]

This may help show the process of a leak down test.

https://www.mobil.com/en/lubricants/...-leakdown-test

[PMK]

Get a probe camera and look inside the cylinder. That might give you an indication as to what exactly is causing the problem. If it is a broken ring it will scar the cylinder wall. Chemtool isn't going to fix that.

While a great idea, typically, we do the scope task after a leak down test. Simply, it can sometimes be very difficult to determine ring condition, unless the visible scoring is evident when visually inspecting. Leak down helps more accurately assess before looking.

[Redbeard]

How much oil is the engine burning? Any signs of oil dripping out?

[wcntech]

No signs of leaks. Smokes at startup and blowing soot out the exhaust. Burning about 1 qt every 100 miles.

[BLUEKNIGHT911]

No signs of leaks. Smokes at startup and blowing soot out the exhaust. Burning about 1 qt every 100 miles.

I'm confused by your wording ..... does it smoke and blow soot ?????? ..... 1 qt. is a lot of oil IMHO .... good luck with this ..... Mike

[IdahoMtnSpyder]

How long ago was the oil changed? Make sure the oil filter was not installed backwards. If so the motor may have been able to pump enough oil to keep from blowing up but not lube the cylinders properly. This is just a WAG, but something is definitely not right. The 1330s just don't burn oil like you say.

[BertRemington]

When did you first notice the oil burning symptoms? Was it gradual or rapid onset? Were there any significant riding events (eg dust storm, very hot day, long-term storage, etc)? How many bars on the temperature gauge? Do the radiator fans operate normally and are temperatures the same at the top and bottom of each radiator? Why did you choose an SM6 and do you consistently keep the engine above 3500rpm?

PS if you keep the Spyder replacing the engine with a used one from a reputable seller is the surest and cheapest path to riding again. However used SM6s are rare so you might have a long wait.

PS is there any discoloration where the middle spark plug's insulator meets the metal base?

[BertRemington]

I'm not liking this. Three 2015 F3s with funky middle spark plug issues and now a 2015 RT.

[Peter Aawen]

I'm not liking this. Three 2015 F3s with funky middle spark plug issues and now a 2015 RT.

It's OK Bert, yours is a 2014, isn't it??

At least, I HOPE it's OK!!

[BajaRon]

I'm not liking this. Three 2015 F3s with funky middle spark plug issues and now a 2015 RT.

I wouldn't be worried. It's probably due to operator error and not some inherent engine defect. The center cylinder is always going to feel the effects of abuse first.

[PMK]

I'm not liking this. Three 2015 F3s with funky middle spark plug issues and now a 2015 RT.

Yes, before posting my previous replies, I considered the same.

This is the third different Spyder in the past few months, with a failed #2 cylinder issue. Granted three does not take down the entire number built, just very oddly coincidental in such a short time between them.

From a technical aspect, it is generally accepted that Nikasil bores, are not known for ring issues if broken in correctly.

[wcntech]

When did you first notice the oil burning symptoms? Was it gradual or rapid onset? Were there any significant riding events (eg dust storm, very hot day, long-term storage, etc)? How many bars on the temperature gauge? Do the radiator fans operate normally and are temperatures the same at the top and bottom of each radiator? Why did you choose an SM6 and do you consistently keep the engine above 3500rpm?

PS if you keep the Spyder replacing the engine with a used one from a reputable seller is the surest and cheapest path to riding again. However used SM6s are rare so you might have a long wait.

PS is there any discoloration where the middle spark plug's insulator meets the metal base?

To Everyone,
I just bought this (for a very good price) from a coworker. He is very meticulous when it comes to maintenance. He noticed the oil burning on a 450 mile ride. About 2/3 of the way through, they stopped to eat and noticed smoke at start-up. He had just changed the oil at the start of the ride. I would say this was a rapid onset of the oil burning because it had not used a drop prior he stated. The temperature is fine, does not leak or lose coolant. The fans operate normally. The middle spark plug is black on the insulator, the other two are a straw color. As far as why did I choose an SM6? I really didn't. It is what it is and it was cheap.

This weekend, I'm going to put it back together enough to get it inspected and registered, change the oil, and do some longer rides to verify it is using oil like he says it is. I have only driven it maybe 15-20 miles. May also take to the dealer to have them see if they can diagnose the issue. Hey it may be something easy. Does anyone know of anything that could be sucking oil into the combustion chamber other than piston rings or valve seals? Maybe vacuum clutch assist, some sort of case vent, PCV, etc?

Thanks!
AJ

[Snowbelt Spyder]

Hey AJ. I’ve got a problem. I try to connect dots. It’s a birth defect.

So, you said that everything was perfect with this motor. Then the previous owner touched it and did an oil change. Then, Boom, suddenly it is burning oil like crazy. Just because he noticed it at lunch doesn’t mean that’s when it started. So, what mistakes can happen on an oil change that might cause this? Dots!

Looks like you already own a 2014 RT, so you know what to look for when you do this oil change.

I’d pay attention to your as found conditions. Oil filter installation. Are both O-rings installed on the end of the oil filter cap stick. The 1330 motor has an integrated dry sump system and oil storage tank. And a common weird drain plug, as you know, with two O-rings separated by a channel, that drains them both. I’d pay attention to see if both O-rings were installed on the drain plug.

Other than that, there is no PCV valve on the 1330. Only a Purge valve - which doesn’t suck oil. Crankcase ventilation is done internally. In order for this to be a pneumatic assist issue with the clutch, you’d have to have a simultaneous failure of both, the pneumatic assist diaphragm as well as the pneumatic assist solenoid valve to fail open, for it to be sucking oil continuously. Otherwise, it would only suck oil when you pulled in the clutch handle. Hope it's something simple, also. Good luck.