2005 Yamaha Kodiak 400 No Start

[Cocoz11]

The atv would not stay running and bogged when given fuel then wouldn't start. I changed plug, worked shortly then same. I put new carb on, cleaned tank, new peacock, worked for two short rides,  around yard perfectly. Started it a couple of times in garage for son and the last time it stalled and now won't start. Turns over nicely, just won't start. Any ideas to try?

[BruceWA]

Ver similar to issues with my “new to me” 2000 Kodiak.  Rebuilt then replaced carb. No real difference. Had great spark than almost nothing! Chased electrical and have ordered parts. Plug cap removed and screwed back on. Coil measures good. Magneto changes from good to bad readings. Can’t test CDI box but found tiny pebbles imbedded in back of it.  Removed them. Put it all back together and it runs great!  Go figure (loose connection somewhere).  Find that idle speed is hard to keep set but seems to be settling down.

Hope my findings can help you a bit.

[Mech]

Check it still has spark ?

[BruceWA]

Mech is correct. Start with basics. Spark and fuel.  

[Cocoz11]

17 hours ago, Mech said:

Check it still has spark ?

I checked with a new plug after I checked and had fuel. It had spark but wouldn't start with the old plug. Changed plug and it started right up. Only issue is old plug was not that old and has a buildup of either oil or carbon on it. Any ideas what could cause it? I'm going to attach pic.

[Mech]

It looks like it's burning oil probably..  If you have a propane burner or welder heat that plug till t stops burning clean, then put it in and start the motor. Warm the motor up and then start opening and closing the throttle, give it about a quarter or a bit less throttle so the revs come up to about three-four thousand revs, then let it off, then on again once it slows but before it gets right to idle. Keep doing that while you watch the exhaust. It will probably start smoking, and get worse and worse the longer you sit there cycling the revs up and down.. If it does, it will be the rings. The other common thing is the valve guide seals, they show up if you let it sit till it's cool, then start it and it will smoke for  a minute or two ..

If it's not oil burning, it must be burning way way too much fuel.. The carby needs checking over.

[BruceWA]

Agree with Mech.  Once you identify the real issue, you have a bit if work in front of you. Very doable with a decent shop manual and tools.  Specialty tools can usually be borrowed from Napa or similar.

[Mech]

Thanks Bruce.

Those readings you said kept changing from good to bad, up a bit... That's probably the gauge you are using. Digital multimeters all refresh their display regularly, and some have a slow count rate, they often don't read fluctuating data correctly every time they refresh. If we want to read something like a pulse coil, it's better to use an old analogue gauge, with a needle.. You may not be able to spot the exact figure because the needle swings up way past it's mark due to inertia, but at least we can see it's getting a pulse. The other option is buy a flasher gauge with a higher "count" rate.. or a max record feature..

And Pebbles in the cdi.. haha.. never heard of that one before.. but whatever.. Good work.

[BruceWA]

Thanks for the feedback Mech.  All my meters are Flukes. I am an old electronics tech and run a one-man guitar amp repair shop for fun. Have access to a Simpson 260.m, will give it a try.

The pebbles look like quartz to me. New CDI arriving today.  Will post an update in a day or so.

[Mech]

Ok..  Good to have you along then.. 

[Gwbarm]

When I see plug that looks like that I think it is flooding, but since you put a new carb on it with no change I would suspect it was not getting a hot enough spark which would point to the cdi, and it also sound like the timing isn't advancing enough to keep up with the increase in throttle which would also point to cdi. It could be burning some oil but I don't think that's your problem, the plug looks sutty black and not shiny black. When its running is the smoke black or blue.

[Mech]

I couldn't make out the pictures too good..  Bad eyes.. And they wouldn't open in my linux machine..

But yeah, the color of any smoke would be a good indicator..

[Cocoz11]

I didn't  see any smoke when I did the short rides. Property is only 4 acres half wood trails so can't really keep speed up for long runs. I'll try goofing the throttle for a while and see if it starts to smoke. Thanks for all the help, one way or another I will get thing running for hunting season here in NY.

Just now, Cocoz11 said:

I didn't  see any smoke when I did the short rides. Property is only 4 acres half wood trails so can't really keep speed up for long runs. I'll try goofing the throttle for a while and see if it starts to smoke. Thanks for all the help, one way or another I will get thing running for hunting season here in NY.

"Goosing"

[Mech]

It could be that the oil you are using isn't tolerant of being used in older/worn motors.

Some oils burn up just fine, some oils when they burn foul plugs..  You might try finding an oil recommended for older or worn motors.. The flasher oils generally have additives in them that foul plugs if they are burning oil.. Plain old mineral oils are better for old motors.

[BruceWA]

Curious about the oil. Lots of OEM statements/qualification on oil use.  Lots of aftermarket opinions too.

[Mech]

Well.. it depends on the brand of oil and what sort it is, but I've found that in old motors, and two-strokes, that some oils foul plugs. High detergent oils seem quite bad for it. They don't get a big thick layer of solid carbon on them, just an oily look.. Just shiny or wet looking, but it really buggers the plugs, even a good clean doesn't always get the plug reusable.. heating them in a flame sometimes does though..

As far as the oil to use goes. These things aren't really super high stress, not like something with a turbo say, or even a modern high revving , fine tolerance motor in a small hot engine bay. The commonest objection I hear to using some fairly bland type of mineral oil is that they have a wet clutch.. well we've had wet clutches for a hundred and more years, and most of them have been just fine with mineral oil.. It's only having to heavy or too lighter oil that effects the clutch.

I've been running all the bikes I've had on plain mineral oil for years, decades actually.... and between myself and my two sons, we've had dozens of them.. Two stroke, four stroke, quads, motorcross, street.. I deliberately buy the plainest mineral oil I can for my own use because then I can use it in everything, including the chainsaw etc..  There is a lot of hype, but when you actually check it out, and actually compare your quad to some machinery, you realise that they aren't really very special at all..

[Mech]

For my customers.. it's castrol, shell, or mobil always, and the spec recommended.. But that's just because of the liabilities aspect..

[Mech]

Oh... and to the original poster..  You could try a hotter plug..  An NGK plug..  In jap bikes, ngk seem to last when nothing else does.. Don't know why, but it can be quite a dramatic difference between ngk and any of the other makes..

[Gwbarm]

If you didn't see any smoke you might have a good tight engine that hasn't been abused, the Kodiaks are water cooled so should run cooler than air cooled engine, less wear.  

[ceedaman]

Is it better to use OEM oil as opposed to aftermarket like Penzoil?

[Mech]

The oem is simpler because they have sourced a suitable oil for you. They don't produce the oil themselves.

If you look in the manual it will say what the requirements are if you don't buy dealer oil. The oil you buy, could well come from the same refining/oil company as the dealer oil.

In N.Z the old trusted brands are castrol and shell..  they have the track record. Over there will be the same thing.. best brands. Is Penzoil a trusted proven brand ?

[BruceWA]

OEM specs are what you are looking for.  The owners manual (online if you don't have one) details all lubricants and their grades for different temperature ranges.  For example, you may use one grade (weight) of oil in the summer and different one in the winter. 

As for name brand, IMHO, make yourself happy.  As long as it meets the OEM specs, you should be good to go.  Different brands add different detergents and the like.  I have found in the past 50 or so years of changing oil that some big name brands have an incredible amount of paraffin, others are more basic.  You will find a great range of opinions when it comes to oil.  My bottom line is that I stick to OEM specs and change it often.  

Mech - Penzoil and Quaker State are old/big names in oil in the USA and more popular in the east than the west. 

[Mech]

Oh ok.. I'd heard of Penzoil, but Quaker State is a new one to me. 

Wealthy quakers..  That's an interesting idea..

 

[Gwbarm]

Recommended oil for Kodiak 400 Yamalube 10W40 or equivalent with API SJ rating.

[Gwbarm]

Synthetic oills burn differently from mineral oils, might explain no smoke. I run mineral oils in all my ATVs and motorcycles that are air cooled. I do run synthetics in all my automobiles . 

[BruceWA]

Quality plugs in small engines tend to be with the money IMHO.  They last longer and do what they should.

As far as oil goes, if you change it regularly and use the correct viscosity, I know of no reason to be fancy with it.  Detergents are OK, but if you’re leaking by rings, etc. fix the root if the problem.

Mech 

[BruceWA]

Any resolution on your machine not starting?  Seems like “we” got off topic a bit.   
Your CDI is suspect in my mind. However, the coil is what produces high voltage to the spark plug.  Coil and spark plug cable (one piece for your machine, I think) is inexpensive and not a hard change out. A new CDI is much more expensive, aftermarket is less expensive but probably for a reason.   Change out is simple.

[Cocoz11]

Not yet, been working doubles. Was going to try and see if an anti fouler would work to keep plug from getting fouled for a while and change the oil and clean the screen.  I'll try all options including cdi before I bring it in to a shop. Starts right up with new plug.

[Gwbarm]

Good choice just ride it, keep some extra plugs and wrench in your tool box so you don't get stranded and get some RPMs up and see if it starts cutting out, best way to diagnose is ride, of course if it starts making loud clanking noises stop.