[manitobadave]

My 2008 610 4x4 with 66 hours has had a number of issues over the winter.
First it started to die on me and then ran rough and only with the choke out.
Our winters are very cold (-35C) so I started using gasline antifreeze. This helped I think.
Then the mule kept popping its oil filler plug off when running and now has started to spew oil from the vent on the top of the fuel pump.
It seems to run fine at the moment except for the oil loss but I assume something is blocked or frozen.
The schematic of the fuel system shows a crankcase breather tube to the pump but is the "breather - #14069" a one way valve?. If so is it allowing oil from the engine to be sucked into the fuel pump ???
I would really appreciate some help before the engine seizes !
Thanks dave

 

[99prairie400]

RCW knows better about this than I but I have seen him describe it a few times.

There is a oil seperator built into crankcase breather line. It's a small container with maybe gauze packed into it? Anyway, water from the crankcase will build up inside of that container and freeze the line making the oil cap blow out and the crankcase pressure to find other avenues of escape.

If you trace the crankcase breather tube you should be able to locate the container and remove it. Take it in a heated space, thaw it completely and then empty it.

Change your oil too. While oil and water don't mix, your crankcase breather works like a humidifier for your engine's bottom end during the warmer summer months and some water will end up at the bottom of the crankcase. You'll need to warm the mule up by leaving it in a heated space and then change it. Hopefully it'll take care of your spewing oil problem!

 

[manitobadave]

610 spewing oil

Thanks so much
It makes a lot of sense when you think about it.
I'll strip the vent line tomorrow
Dave

 

[ldand]

The filler plug blowing out is caused by the little breather hose coming from the valve cover to the carberator freezing up. Take it off, plug the nipple on the carb and put a new hose on the valve cover vent and run it into the lower side of the air box. Take it back to your dealer and they know of this problem and should take care of it for you. The reason for it not running is the pulse line coming from the crankcase and the oil seperator freezing, make certain the little plastic oil seperator is on in the right dirrection, mine was on backward and frooze often, I looked through the service manual and discovered it was on backwards and the inlet line was coming in on the bottom of the canister. You will see when you look at it, the inlet (the end with two nipples and one is plugged) should be facing toward the crankcase and the end with one nipple should face the fuel pump. If you run it in cold weather you will have to take it off and empty it on a regular basis. Also, as soon as your oil starts to turn milky you will have to warm it up and drain it and change filter. You have to keep the moisture out of it. I use mine all winter ice fishing and had a heck of a time with it the first winter, now I have discovered the problems and everything is great. Too bad Kawasaki doesn't test these machines in the cold and maybe they would do something about it. Sorry for the long post but I did not know how to explain it any shorter.
Hope this helps.

 

[manitobadave]

Thanks
I did check the plastic oil separator and guess what... it was on backwards!!
I've only run it for a short time since I reversed it but so far so good.
I bought this machine in ND and exported it to Canada so my local dealer is less than thrilled with me. If I need to do the modification myself, do I disconnect the vent line from the top of the fuel pump under the seat and then drill a hole in the air filter box and fix it there ? Then plug the open nipple on the fuel pump? Sorry if I'm being dumb I just want to get it right.
Thanks again Dave

 

[ldand]

Dave,
No, you do not disconnect the line on the fuel pump. The line is the short coocked line on top of the carberator that runs to the valve cover, that is the one that freezes and builds up pressure and blows out the filler cap. It is a hose about 3/8" diameter, you cap the nipple where you take it off the top of the carberator and put a hose on the nipple where it comes out of the valve cover and drill a hole in the lower side of the air box and run it in there, drill the hole a little smaller than the hose so you have a tight fit. This will take care of the filler cap/dip stick blowing out. It will also put some moisture and oil film in the bottom of the air box that you will have to clean out about once a year. This is what I did with mine a year ago and everything is good this year and it has been a cold winter. It is an easy fix, hope I explained it for you. If you have anymore questions feel free to ask.
Larry :-D

 

[manitobadave]

Replumbed mule

Just wanted to say thanks to you guys for the help with the oil spewing mule.
Finally I made the modifications and all appears well. The only reason it took so long is because access to the carb is a nightmare and I kept hoping I might be able to avoid stripping the air intake. Anyways its done.
Thanks Dave

 

[Mule610Canada]

Re: Replumbed mule

Hey Guys, i just created my account because I'm also having these problems with my mule. Im from Alberta, so its not much different than manitoba. Last year i had these problems, and it never worried me. This year i am getting really frustrated, because i drive it, and the filler cap blows off, causing it to spray oil literally everywhere. I also get it running really rough, and get oil coming out of the fuel pump. I Reversed the oil separator, and that didnt help. I looked at the crankcase breather, and there isnt anything in it like gauze. Im starting to believe i shouldn't have ever bought a kawasaki. The machine runs fine for a few minutes, then acts up. Its -4C today, and the problems are just getting worse. i changed the oil to 5W30 three weeks ago, but didnt bother to put synthetic in. I cant find an oil filter anywhere, even at the 6 local dealers. The oil is getting to be a milky colour, and im planning on changing it and the filter tomorrow. What do you guys suggest? what would it do running a line from the crankcase breather to the air box? Thank you so much in advance, i know there is somebody out there who has the solution.

 

[manitobadave]

Sorry to hear about your Mule issue
Two things come to mind.
I rerouted the crankcase vent tube into the airbox as described in the post and that certainly improved things. Just make sure the tube is big enough and cant be kinked. You will find ice in the bottom of the airbox after that mod. It pays to run the Mule until its warm and try to evaporate the water vapour although I'm not sure where the water comes from ??gasoline- short runs cause more problems. I had no luck with changing the filter in the gasline but I wonder if gas antifreeze will absorb the water and help ?

I had gas in the oil recently also causing engine stalling issues and it was caused by a damaged float in the carb. Apparently the Mule carb is prone to this.
Even in -20C weather the Mule has been running OK
I get my oil filters from the Kawasaki dealer and can get you the ref # if you need it.
I use 0-30 synthetic I think.
Good Luck
Dave

 

[Mule610Canada]

Thanks for that info, I changed the oil and all seems to be good. I'm going into town right now to pick up some line to re route that line. The line we are talking about is a short one coming out of the top of the engine, and has a breather on it? Like the one that drains condensation out of the engine? It's about 6-7inches long

 

[jeffandtamara]

Getting ready for the cold weather coming...Last year I had trouble on my 610 with the oil becoming milky. No other issues observed. However, I had seen this post last year and wanted to try some of the suggestions listed before... When I got to looking at the crankcase plumbing I was not seeing what I thought was being discussed.
Can someone Identify the parts I have taken pictures of and let me know if I am on the right track?? Is the clear plastic tube the breather Filter they were referring,,, and what is the round plastic looking part the hose go into???
I talked to the dealer today,,,Seems like they know something, but didn't want to act knowledgeable of any problem??? They just wanted to make sure you always run the Mule enough every time you start it up to evaporate any moisture that might accumulate.... Thanks for your help.

I am hopefull the pictures attached....
View attachment 66945 View attachment 66937

 

[jeffandtamara]

Just wanted to update: It has been pretty cold, checked the oil and it is starting to look milky again this year. The way I use the mule I just don't get it up to temp for very long. I plan to take it for a long ride and get it up to temp for a while with the thinking that it will evaporate most of the moisture??, but this just doesn't seem to be right, there should be a better design than this....

 

[imported_cookie_monster]

Those engines are generator/lawn mower engines. They were designed to run 3500-3600 RPM under a load continually. Running them at lower speeds will make them "milk" the engine oil. Especially in cold weather. There's ways to band-aid it but it really doesn't hurt anything to speak of (unless it ices up in the crankcase). Frequent short trips make things worse. So, how does it get moisture into the oil?

Engine is cold, you get in and start it up. Run down to the mailbox and back, and you're done until tomorrow. Engine temp gets up to, maybe 75°F? Well...as the engine warms then cools back down, moisture condenses on the inner parts. It drips down into the crankcase oil (sump). Next day you do the same routine. More condensation. It repeats over and over until one day you pull the dip stick and it's over filled and the oil is white. Then you get scared and call the dealer that sold it to you and tell them that they owe you a head gasket. (been there, done that). There is nothing wrong with it IF that is the way the mule is used. It was explained to me by someone at Kawasaki that these engines-and the engines of all of the Mules (except the pro FXT) are all originally designed to run full throttle against the governor all the time. They "like" to be run like that and it doesn't shorten the life one bit. If anything, they live longer. This is also important to note on the 4010's, with fuel injection, that tend to "carbon" up the intake manifold, which hangs the throttle plate open a little, which then confuses the ECU into thinking your foot is on the gas, and then it tries to compensate. Run them harder-problem avoided.

 

[jeffandtamara]

Thank you Cookie monster: You are right I rarely ever run the mule at WOT. Usually I run the mule for 15 minutes or so at a time. So depending on the outside temperature, I could see where the actual engine temperature might not be that high. Last week we had a warm weekend and ran the mule for an hour or so, and checked the oil. At that point I could no longer see any of the "Milkyness" in the oil. I guess if you get the engine temperature up above 212 for a while the moisture will evaporate out??? Not sure.... However, My work truck gets driven for about 15 minutes, twice a day every day and is water cooled to approx. 180 degrees, and the oil does not get milky....I really like the mule and want to take care of it, so I am glad to hear that the milky appearance of the oil might not be that bad for the engine...

 

[harryb48]

I read this thread last week after my 2005 Mule 610 blew the dipstick out and sprayed oil all over. I have owned this machine since new and this is the first real problem, other than batteries, that I have had with it. I use this machine to haul all my fire wood in the winter and plow about a half mile of driveways in central New York. I always leave it idle while loading and unloading wood and run the engine rpm relatively high when plowing. The day it froze the temperature was about -25 with the wind chill factor and I had just finished up all the driveways. I followed the advice given here with one exception, I vented the crankcase to atmosphere and plugged the fitting on the carburetor end and apparently my problem is solved as it has run perfectly since. I am a bit confused as to the separator on the vacuum line for the fuel pump being reversed. I believe I will come up with a little different configuration come warmer weather using a vertical unit the enters and exits from the top.

 

[jeffandtamara]

Thanks for posting Harry.... I think if I had not been watching the oil very closely, I would have ended up in the same situation. When you make your final modifications could you take a couple of pics?? I know I would really appreciate it and I am guessing there are a few more 610 owners out there that would be interested...

 

[imported_cookie_monster]

mentioned venting and separators to the rep.

If the Mule is driven properly, e.g. not idling excessively, it won't make oil, period. That engine was not designed to run in super cold air temps and at idle and lower speeds. If it's not on the governor, it's not working hard enough (per kawasaki). Remember, they do have low gear in the 4x4 units, and it's suggested to use it when you're not having to run 15 mph or more.

 

[royliljequist]

Hi, I have the same problem.
I have a 2018 Mule sx and the oil cap keeps coming(popping) off.
It has 50 hours on it.
It is still under warranty so I'm afraid to touch it.
I'm just looking for answers. Thanks

 

[DRJCO]

Getting ready for the cold weather coming...Last year I had trouble on my 610 with the oil becoming milky. No other issues observed. However, I had seen this post last year and wanted to try some of the suggestions listed before... When I got to looking at the crankcase plumbing I was not seeing what I thought was being discussed.
Can someone Identify the parts I have taken pictures of and let me know if I am on the right track?? Is the clear plastic tube the breather Filter they were referring,,, and what is the round plastic looking part the hose go into???
I talked to the dealer today,,,Seems like they know something, but didn't want to act knowledgeable of any problem??? They just wanted to make sure you always run the Mule enough every time you start it up to evaporate any moisture that might accumulate.... Thanks for your help.

I am hopefull the pictures attached....
View attachment 66945 View attachment 66937

I recently purchased a 2012 610 and it acts like it is running out of gas after a few minutes. At that point I can usually keep it going fully or half choked. Someone replaced my three port breather with what looks like a fuel filter. I have ordered the breather but do not know what to do with the third nipple or which direction to mount the thing. I am unable to see where the hose actually connects that is heading towards the engine, The other goes to the fuel pump. there is a short hose that hangs loose out of the carburetor, The hoses from pump and valve cover are in place. Please help

 

[DRJCO]

I recently purchased a 2012 610 and it acts like it is running out of gas after a few minutes. At that point I can usually keep it going fully or half choked. Someone replaced my three port breather with what looks like a fuel filter. I have ordered the breather but do not know what to do with the third nipple or which direction to mount the thing. I am unable to see where the hose actually connects that is heading towards the engine, The other goes to the fuel pump. there is a short hose that hangs loose out of the carburetor, The hoses from pump and valve cover are in place. Please help