no turbo and I don't have money for a different compression gauge to fit In the spark hole. wish the plugs weren't buried 4 inches under the valve cover
2018 rtv-xg850 running like trash at only 125.5 hours
- Thread starter truckfixer
- Start date
gas smell was when it ran really well. there is no more gas smell and runs and idles like total garbage
No gas smell on mine
Are you getting spark on both plugs?
Out of curiosity try pulling one plug wire and see if it runs any different. Then plug back and try the other one.
My daughter's car with coil over plugs started doing that intermittently. Was a bad coil, would work for a while then suddenly lose power and run rough.
Hopefully these are readable
whitetiger
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Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Try fasting your seat belt. There is a speed limiter on the RTV-XG850.
RCW
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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
@whitetiger - that’s why you and a few others are so important here on OTT.
Whodda think about a seatbelt?!?!
whitetiger
Moderator
Staff member
Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
compression test on these is inconclusive-in that they have an automatic compression release. So if the engine is in great shape it might have 180 psi. If it were worn enough to smoke, it'd still have 180 psi. A lot of the modern small engines have this feature-eases loads on the starter among other things.
seat belt sensor can cause this issue. So can a bad fuel pump, and a bad fuel pump is generally related to poor gas which can be attributed to sitting. Fuel goes old. Also the end of the pump has a "sock" (what I call it, it's a filter) on it that plugs up if there is contamination in the fuel tank. Did a Polaris last month, at the guy's house, he says he has to keep replacing fuel pumps. I pulled old pump out, the sock was black and dirt was falling off. Look down into the tank (which is white...easy to see "stuff" ) and there staring me in the face, a ton of dirt and water. Well no wonder. He said put the $&*)O& pump in it cause that dirt won't hurt nothing. Yes sir. He'll be out another $700 pump by next week probably. The pump is lubricated by....gas. When you starve it for lube, the pump itself won't last long. And a plugged sock definitely starves it for fuel.
seat belt sensor can cause this issue. So can a bad fuel pump, and a bad fuel pump is generally related to poor gas which can be attributed to sitting. Fuel goes old. Also the end of the pump has a "sock" (what I call it, it's a filter) on it that plugs up if there is contamination in the fuel tank. Did a Polaris last month, at the guy's house, he says he has to keep replacing fuel pumps. I pulled old pump out, the sock was black and dirt was falling off. Look down into the tank (which is white...easy to see "stuff" ) and there staring me in the face, a ton of dirt and water. Well no wonder. He said put the $&*)O& pump in it cause that dirt won't hurt nothing. Yes sir. He'll be out another $700 pump by next week probably. The pump is lubricated by....gas. When you starve it for lube, the pump itself won't last long. And a plugged sock definitely starves it for fuel.
i mean thanks but I hate the seat belt alarm so much I always have it on. especially since it's quite loud
if I unplug anything on the coils or fuel injectors the engine just dies. though it has recently started running better after its warned up for awhile. backfired loud enough to make
runs like crap rn but will run better after it gets to temp and stays there for maybe about 10 minutes and it sounds like a box of rocks after about 3250 rpm
I do have another weird issue where the fuel tank vent only vents to keep the tank from exploding. it's still building alot of pressure in the tank despite me cleaning the vent valve and replacing it once already
Did you ever get around to testing your fuel pressure?
Did you check/adjust the valve lash? I didn’t read back through all the thread but a number of suggestions had been made. We just had another rtv with backfiring not too long ago that if I recall turned out to be valve lash.
Did you check/adjust the valve lash? I didn’t read back through all the thread but a number of suggestions had been made. We just had another rtv with backfiring not too long ago that if I recall turned out to be valve lash.
fuel pressure was within spec and checked out fine, not sure about flow rate but seems to be about half a gallon a second or there about, lash was perfect and didn't need adjustment
whitetiger
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Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
it's holding the right fuel pressure the whole time and really only runs worth a shit at wide open throttle currently, I pulled the plugs again and they look great like it's running perfect
I keep thinking about how excessive un-burnt fuel ends up in the crank case which also makes me think of an ignition or timing issue.
This seatbelt issue - does the ECU just stop firing one or more of the cylinders to retard the engine while the fuel pumps and injects merrily away into the cylinders forcing the un-burnt fuel to get dumped in the exhaust stroke or squeeze past the rings in the compression stroke?
The ECU is just running software after all...who knows, maybe the ECU software is buggy and got orphaned between Subaru and Kubota when K tried putting a motor designed as a constant speed power unit into a variable speed application. Techs here in N.A. won't be able to diagnose these black box issues when the designer in Japan either gave up, dropped the ball or died during covid. Kubota Japan probably knows there's an issue but doesn't have or doesn't want to allocate the resources to fix the problem.
This seatbelt issue - does the ECU just stop firing one or more of the cylinders to retard the engine while the fuel pumps and injects merrily away into the cylinders forcing the un-burnt fuel to get dumped in the exhaust stroke or squeeze past the rings in the compression stroke?
The ECU is just running software after all...who knows, maybe the ECU software is buggy and got orphaned between Subaru and Kubota when K tried putting a motor designed as a constant speed power unit into a variable speed application. Techs here in N.A. won't be able to diagnose these black box issues when the designer in Japan either gave up, dropped the ball or died during covid. Kubota Japan probably knows there's an issue but doesn't have or doesn't want to allocate the resources to fix the problem.
I think you hit the nail on the head about Kubota not having resources to address this. Another part of the equation seems to be combustion air temp. These engines see less contamination when the air temp is above about 60 degrees Fahrenheit I am seeing. That long plastic intake tube to the front must affect that greatly. Adding heat in the warm weather and further chilling the air when cold. To balance that out would most likely be a nightmare for simple ecu setup we have. The longer runners on the new intake manifold could actually have been implemented to equalize that with engine heat. Even with my engine fully warmed up running it in the cold causes major contamination. Kubota knows about it now and has finally at least in my case is looking into a solution if what I have been told is 100% accurate. With soo much gas evaporated from the crankcase and in the drain oil I have no idea how they come close to partical emissions standards.