Massimo Buck 400 Check Engine Light

[Joe Toup]

The Fumoto would probably make it much easier to drain the oil before pulling the screen to check for particulates.  Changing oil makes a mess unless you have a funnel right up next to the plug.  Great concept.  My preference would still be to remove the screen after draining.  

[Joe Toup]

7 hours ago, j.fulciniti said:

After busting my knuckles 12 times, I could not get the drain plug off.  Of course, my ramps are at my brothers house 40 miles away.  I'll have to table  this issue until later next week as I'll be out of town for several days.

Thoughts from the posts above.  I do not believe the 2020 Buck 400 model has the Hisun engine mentioned above.  It's Chinese for sure but I read that Massimo ditched that engine in 2018 or 19.  There is some mention of belts  which I gather means drive belts.  This unit has a shaft drive.  

Drove up 2 steep hills in low and came down both in neutral.  NO CEL. 

Drove up a steep a 3rd time in High and came down in neutral - NO CEL. 

Hill #4 up in high and down in high - you betcha - CEL came on. 

Drove back to the garage, let her sit running for a few minutes, CEL went off. 

To be continued ............

Did you drive down the hill in low at all?  

[Travis]

1 hour ago, Mackc said:

Kind of fantasizing here, (bought a Buck 400 with 208 miles less than a year old runs fine so far, been reading on this forum.

Since  I can't lie down on the ground (Had a broken hip and being old and lame) withthe oil pump with drain is at the rear of the sump, would it be okay to use the winch and pull the front of the UTV up at a 45 degree uphill angle drain the oil ,replace the plug, let it down with the winch and fill it with motor oil?  Also where could one of the Fumoto valves be purchased online?

http://fumotousa.com/

there are also quite a few suction pumps online for changing oil, with a long hose you can stick through the dipstick hole if possible. they're either hand pump or battery.

[j.fulciniti]

36 minutes ago, Joe Toup said:

Did you drive down the hill in low at all?  

I'll try that tonight if the rain holds off.    

Say I use Low to go up and down the steeper roads with no CEL issues.  

I read your post earlier that given my driving habits, I should be driving in low way more than I do.

Perhaps the CEL issue is -------- Operator Error.

 

[Joe Toup]

6 minutes ago, j.fulciniti said:

I'll try that tonight if the rain holds off.    

Say I use Low to go up and down the steeper roads with no CEL issues.  

I read your post earlier that given my driving habits, I should be driving in low way more than I do.

Perhaps the CEL issue is -------- Operator Error.

 

I wouldn't necessarily say that.  I go up and down some steep hills in high and low.  Have never had the CEL.  But that doesn't mean I won't.  Your problem is one that may affect many of us.  Will be interesting to see what the real cause it.  Many of us curious.  This kind of stuff is in my veins!  

 

[T-boss 410]

I apologize for being off topic, but I am getting the idea that removing the oil drain plug is a very difficult task. How have some of you got it broken free?

[Joe Toup]

47 minutes ago, Joe Toup said:

 "I do not believe the 2020 Buck 400 model has the Hisun engine mentioned above.  It's Chinese for sure but I read that Massimo ditched that engine in 2018 or 19. "

 

J. Fulciniti - After doing some digging on the engine, I believe you are correct.  Found some info using the engine family from the identiplate under the seat on the frame rail (Shows displacement, spark plug gap, timing, etc).  Turns out there is a company called Taizhou Nebula Power Co., Ltd., located in Taizhou City, Jiangsu Province, China.  They make a series of UTVs that is nearly identical (minus badging) to the Massimo, Bennche, Linhia, and Cazador.  They have a model # XY450U-A. The engine model family (KMMMX.391XYB) can be seen on the attached spreadsheet line #884.   The irony is, the engine is nearly identical to a Hisun the best I can tell.  I have not been able to find anything yet that convinces me it is made any differently.  They may have sold the series to Taizhou.  Not sure since Hisun is still in production.  In theory, they should operate the same and be repaired and maintained similarly as a Hisun.  

The website for Taizhou Nebula Power Co is here: http://www.tznebula.com/eng/  Some of their links, while not specifically named "Massimo", do provide some great info that should be beneficial as we build a repository of owner background info on these Massiomo/Bennche/Cazador/Linhai 400's. Stinks we have to do this kind of searching to overcome the shortfalls of the company.  But it is what it is. 

 

off-road-mc-atv-utv-recveh-2006-present.xlsx

[Joe Toup]

10 minutes ago, T-boss 410 said:

I apologize for being off topic, but I am getting the idea that removing the oil drain plug is a very difficult task. How have some of you got it broken free?

19mm socket, 3/4 inch drive ratchet, 6 inch extension.  Comes right out....

Once you break it loose, put one of those deep funnels under it through the hole in the plastic skid plate, then reach in from the driver's side and turn the nut until is falls out and into the funnel.  The screen will drop out with it,  Once the oil is drained, drop your funnel and pull out the screen and plug.  Check for debris in the screen.  Then clean everything off with paper towels. Reinstall.  Take your dipstick out, unscrew the tube, then use a smaller funnel with a tip that goes into the hole.  Add 1.25 quarts of 10W40 UTV oil made for a wet clutch.  Reinstall tube and dipstick.  Check oil level, Boom!  Done.  Be sure to check the oil level after you run it to make sure it didn't drop any.  And check for leaks at the plug and dipstick too to make sure you got it closed back up right.  Then hit the trails....

[kenfain]

To be honest, I have a different brand machine altogether. So I have no idea what it takes to clean that screen. If the fumoto doesn't have to be screwed in, and out with each oil change, I think it would be ok. But since the fumoto is made of brass, and has a fiber washer. Then there's plenty of chance with each oil change, for things to go sideways, or for it to eventually leak, if it has to be screwed out to get to that screen.

But a cleaner oil change is pretty much assured. Since you just snap the hose on the valve, put the other end in a bucket, and flip the lever.

[kenfain]

48 minutes ago, j.fulciniti said:

Perhaps the CEL issue is -------- Operator Error.

 

I really doubt that it is. The machine shouldn't have that narrow of a performance band. Unless that hill was so steep that you couldn't get up it, if it were dirt. Even then. it shouldn't be anything more than having the machine struggle with enough power. If it even did that. Not a CEL.

Besides you get the CEL mostly  going down, not up. I think that it's starving for oil, when the nose is much lower than the tail. Anything more than idle rpms put more demand on it. That oil change might give it the boost in pressure that it needs, to stay on the good side of that CEL threshold. 

[T-boss 410]

1 hour ago, Joe Toup said:

19mm socket, 3/4 inch drive ratchet, 6 inch extension.  Comes right out....

Once you break it loose, put one of those deep funnels under it through the hole in the plastic skid plate, then reach in from the driver's side and turn the nut until is falls out and into the funnel.  The screen will drop out with it,  Once the oil is drained, drop your funnel and pull out the screen and plug.  Check for debris in the screen.  Then clean everything off with paper towels. Reinstall.  Take your dipstick out, unscrew the tube, then use a smaller funnel with a tip that goes into the hole.  Add 1.25 quarts of 10W40 UTV oil made for a wet clutch.  Reinstall tube and dipstick.  Check oil level, Boom!  Done.  Be sure to check the oil level after you run it to make sure it didn't drop any.  And check for leaks at the plug and dipstick too to make sure you got it closed back up right.  Then hit the trails....

3/4 inch drive? Holy crap!!! I don't own a drive that big. My biggest is 1/2 inch drive. Why is the darn thing so tight, anyway?

[j.fulciniti]

2 hours ago, Joe Toup said:

Did you drive down the hill in low at all?  

Fired her up, put it in low,  drove around and up and down our steep hills 4X.  Never took it out of low and NEVER saw the CEL.

Prolonged downhill in N or L does not set off the CEL but H does.

[T-boss 410]

Sounds like you've got it pretty much narrowed down. If I were you, I'd get the oil changed as quickly as possible. If for nothing else than my own piece of mind.

[Joe Toup]

27 minutes ago, j.fulciniti said:

Fired her up, put it in low,  drove around and up and down our steep hills 4X.  Never took it out of low and NEVER saw the CEL.

Prolonged downhill in N or L does not set off the CEL but H does.

Based on what you experienced, my money is still on the belt (90%) or perhaps the clutch (10%).  Do a Google search for CVT theory of operation. It will explain the difference between operating in high versus low. There are some great articles about Polaris CVT. The theory is pretty much the same.

Do that oil change very soon. It’s needed.  But after you do, try running it up and down hills again in both high and low gear.  I’d put a 6-pack on it that it still throws the CEL in high gear.

Final thought.  If it’s working in low, ride it and enjoy it.  But sooner or later you’ll probably need a new belt.  

My hunch is when in high gear going down a hill, if the belt has stretched some, due to constant riding in high, there’s probably not enough tension on the primary and secondary clutch assemblies to keep them in sync thus causing driveline slip.  Which is probably causing the crank position sensor to see the slip difference/ratio from engine output compared to the wheel rotations. This would throw your check engine light. When you put it in low, some tension stays on the driveline as you go down hill and your crank position sensor is probably not seeing any slippage.  Again, just a hunch.  But the results of your “experiment” are leaning me in that direction. You will be able to rule out the oil sump situation if you change it and it still throws the CEL afterwards in high going down hill.  

Good news is, you are zeroing in on the culprit and we all learned something. This has been a very interesting thread.  

[Joe Toup]

47 minutes ago, T-boss 410 said:

3/4 inch drive? Holy crap!!! I don't own a drive that big. My biggest is 1/2 inch drive. Why is the darn thing so tight, anyway?

LoL. Sorry. 1/4 inch drive. Typo.  Wife was driving. I left my readers at home. 1/2 drive would be perfect.  

[Joe Toup]

Check this link out. It does a better job explaining what I was trying to convey with the CVT and high gear versus low gear in a UTV. 

https://www.standard.net/lifestyle/recreation/atv-adventures-choosing-the-right-gear-range-is-important-on-the-trail/article_389a114b-488b-55b9-a6ce-80b3b5788563.html

 

 

[kenfain]

5 minutes ago, Joe Toup said:

You will be able to rule out the oil sump situation if you change it and it still throws the CEL afterwards in high going down hill.  

I believe the best way to narrow it down between the two possibilities, would be to park on that hill. Pointing downhill, and gun the motor a bit. See if it will come on, while stationary. By taking the belt out of the equation. That will eliminate all possibility of conflicting results. Otherwise, you could be correct about the belt. I think it unlikely with so few hours, but I've seen much stranger things. 

It has been interesting, but I'm ready for definitive conclusions. 

[T-boss 410]

1 hour ago, Joe Toup said:

LoL. Sorry. 1/4 inch drive. Typo.  Wife was driving. I left my readers at home. 1/2 drive would be perfect.  

Lol, thanks. Had me scared for a minute there. But, I have read a few posts where the complaint was that the drain plug was so tight it couldn't be removed. You didn't have that problem?

[j.fulciniti]

12 hours ago, T-boss 410 said:

Lol, thanks. Had me scared for a minute there. But, I have read a few posts where the complaint was that the drain plug was so tight it couldn't be removed. You didn't have that problem?

I could not get mine loose / off.  I was not able to get any leverage.  My unit will sit until Sunday when I can take it to my neighbors house, use his lift and "real tools".

Funny / not so fun story - while pulling hard my socket slipped off drain bolt and I cut my hand on the edge of the skid plate.  Then turned my head around and skinned my nose on the other side of the plate.  Nothing bad but I looked like some one beat my ass in my garage.  I still look pretty stupid with that scrape on my nose today.
 

[kenfain]

13 hours ago, T-boss 410 said:

Lol, thanks. Had me scared for a minute there. But, I have read a few posts where the complaint was that the drain plug was so tight it couldn't be removed. You didn't have that problem?

It's not unusual to have an extremely tight drain plug the first oil change. The plug was installed at the factory on bone dry threads, by someone who could easily get away with maximum torque. 

So it isn't surprising that it's frozen in place. When you reinstall the plug, just make sure that it's finger tight, plus MAYBE an eighth of a turn. Just enough that it'll neither leak, nor vibrate out. Because you don't want to strip, nor stretch those threads.

Factory threads in an aluminum block are a fragile thing. And they're a one time thing. If you mess that up, there's no getting them back.

 

[T-boss 410]

Lol. I know what you mean. I do a lot of work on my own vehicles, and can't remember the last time I did any work without getting beat up in some manner. Just changed the spark plugs in my Ram yesterday, and I have the cuts and bruises to prove it. I admit I do let go with some choice language, but it's a stress reliever, if you know what I mean.

[T-boss 410]

Thanks for the tip! Is the plug aluminum, as well? What size is the o ring?

Edited October 1, 2020 by T-boss 410
Additional information

[kenfain]

52 minutes ago, j.fulciniti said:

I could not get mine loose / off.  I was not able to get any leverage.  My unit will sit until Sunday when I can take it to my neighbors house, use his lift and "real tools".

Funny / not so fun story - while pulling hard my socket slipped off drain bolt and I cut my hand on the edge of the skid plate.  Then turned my head around and skinned my nose on the other side of the plate.  Nothing bad but I looked like some one beat my ass in my garage.  I still look pretty stupid with that scrape on my nose today.
 

Once you get that plug out, there's no reason why you should ever have that problem again. Those threads will be lubricated with the drained oil. And you can't use factory torque anyway. 

[kenfain]

1 minute ago, T-boss 410 said:

Thanks for the tip! Is the plug aluminum, as well?

I've never heard of an aluminum plug. It'll be steel, or brass, but probably stainless steel. 

[T-boss 410]

What about the O ring? Does it need to be replaced at each oil change? I have a rather large collection of O rings, but I don't know if I have any large enough. 

[kenfain]

Just now, T-boss 410 said:

What about the O ring? Does it need to be replaced at each oil change? I have a rather large collection of O rings, but I don't know if I have any large enough. 

As I've said, I don't own one of these. Most everything I comment on, is general knowledge from many years of mixed experience. 

But about your O-ring. If it's truly a rubber O-ring, then I'd keep reusing it, after checking it for damage. And putting a little liquid silicone on it, to make it last a bit longer. 

I'd most definitely match it up with a new one, at the next oil change, to be used as a spare when the original gives up. Replace it every couple of years, as it coincides with normal oil changes. Or sooner, obviously, if there's any sign of anything other than perfect. 

[T-boss 410]

Very good, sir.  Thanks!

[Travis]

Oh come on, this is how you tighten an oil drain plug!

 As for the O-ring agree with Kenfain, My mule doesn't have a crush washer or o-ring, just a steel (stainless probably) washer, it never leaks a drop.

[T-boss 410]

OK, thanks. I don't know what the O ring composition is. I only have seen it in a parts diagram. 

As for the pic, I can only hope it won't take that kind of torque to get the plug out 😕

[Mackc]

On 9/30/2020 at 1:58 PM, Travis said:

http://fumotousa.com/

there are also quite a few suction pumps online for changing oil, with a long hose you can stick through the dipstick hole if possible. they're either hand pump or battery.

Thanks, from one Texas old codger to another Texan,  good idea, I ordered an 12 volt oil scavenger suction oil changer pump yesterday for $18 plus change from Amazon.  I also have a set of 1/2" metric deep sockets to pull the dipstick/oil filler bushing out with, I didn't get the original Spark plug wrench looking tool from the P.O. I think the dipstick tube will pass thru the 1/2" square opening in the deep socket if not I will drill it out and weld another 1/2"socket on top of it.  I have an old automatic tranny filler extended funnel to refill the oil sump with. I saw in the owner's manual that the engine holds 0,34 gallons, what a figure for an oil change! I also got a six pack of quarts of Valvoline Motorcycle/ ATV, etc., etc. conventional 10W - 40W oil ordered from Walmart.com  ($18 plus change), since I live over 40 miles from a Walmart store. The $5.99 shipping for a purchase under  $35 is a bargain for me.

I want to extend my thanks to all that have posted about this subject which is hardly worth reading in the manual