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Kodiak 450 lacking power after top end rebuild

7K views 36 replies 10 participants last post by  Lagernuts 
#1 ·
Ok, found a local guy that said he was a Kawasaki certified mechanic. He rebuild my top end since it was smoking, and I bought a new OEM carb to eliminate that from the problem. It starts and runs good, but it's lacking the power it had before. It used to have a snappy throttle and it would hit 50 plus, but now it is sluggish and hits 30-35 or so. I replaced the plug and the filter is clean. I do have a compression tester, but the adapters won't fit the plug hole. The belt was cleaned up by the Yamaha dealer before the rebuild. The quad looked like new when I bought it used with 200 miles (2006 model SE), but the engine seems to have a lot of red clay stains all over it and the belt was slipping due to water in it. I think the guy might have sunk it, but it ran great for the first few hours. All the fluids look good and were replaced by the dealer. The guy that rebuilt it left a plug loose, so the diff lock was locked on. He fixed it, but I'm thinking he isn't real familiar with Yamahas. Any suggestions? I promise to post the final outcome as that is my biggest pet peeve with these forums. Thanks in advance for any tips. I've rebuilt a Foreman and Yamaha Waverunner, so I get engines for the most part:wink2:
 
#2 ·
The red clay indicates mud riding and it might have been swamped, but it did run for a while.
I would check for correct valve lash and float level for proper fuel flow.
 
#3 ·
Valves

I am going to get the valves checked next week. I get annoyed with the carb adjustments, so I bought a new OEM one for $266. The plug looks to be lean, so I plan to adjust the air screw next week when we get to the farm. My old Honda 110 three wheeler had more response than this one has atm. I hope it isn't compression, but I'm kinda thinking that may be my problem...
 
#5 ·
Getting fuel to the carb from the tank and getting fuel to the engine is 2 completely different things. The float level in the carb must be properly adjusted to make sure the proper amount of fuel is in the carb bowl. Since your carb is new, it now must be setup correctly. Float level and pilot needle adjustments are part of that.

I would definitely check the valve clearances again as well. They should of change by simply replacing a piston, but you never know what the mechanic might of done.

I would also re-check the timing. It may be off by one tooth on the chain.
 
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#6 ·
If you replaced the piston, your kinda wasting your time with the compression test. It will tell if you have enough to run, which you already know, but your not going to get a real reading until its broken in. I wonder if you got a new set of rings on an old piston, and no hone job, or it was redone but didn't check the bore, and it needed a bore and hone, not just a hone. Hard to say. If you got it up to 35, and it wasn't sputtering and bucking or falling flat on its face, I'd say the carb is close to adjusted. If not it would either not idle at all, or it would but wouldn't rev up, one or the other. If you have both, its fine. I'd look for cross hatching in the cylinder, the parts he put in, and if that looks good. Put 500 miles on it and see if it gets better as the cylinder seals up. Also, follow proper break in procedures.
 
#7 ·
......The belt was cleaned up by the Yamaha dealer before the rebuild. ........:wink2:
Besides checking all of the above...

Pull off the cvt cover and check the movement of the belt. May have a roller weight flopped out of the channel.
 
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#9 ·
Kodiak

I'll get the dealer to check the timing as well. The mechanic said he was going to get the cylinder honed, but a few weeks went by before I checked on the quad. The next day he said it was ready, so I'm worried that he just put new rings on and didn't fix the original problem. I guess I'll get the valves and timing checked and see how it goes.
 
#10 ·
I'll get the dealer to check the timing as well. The mechanic said he was going to get the cylinder honed, but a few weeks went by before I checked on the quad. The next day he said it was ready, so I'm worried that he just put new rings on and didn't fix the original problem. I guess I'll get the valves and timing checked and see how it goes.
You may have just exposed your problem;
The dealer doesn't do crap, and most dealers hire the cheapest labor available to boost dealer profit.
If you can, get to the parts remover/replacer guy and tell him if the valves do not close fully these low compression engine will not run correctly.
If you have popping through the intake, which have not spoken of yet, that is a good indication the intake valves are not closing, and if there is too much valve lash the valves do not stay open long enough to get all the gas needed to haul ass at 50 m.p.h. as before.
Let them know you know something about these engines, and if you need more help fighting the 'dealer guy' just ask.
Generally, it's 'Us' on G.C. against all 'dealer guys' and most of the time 'they' lose.:wink2:
 
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#11 ·
Thanks

I appreciate all the advice. I'll be able to run it all next week, so I'll check the plug and tweak the carb if it needs it. It doesn't have popping unless I let off from full throttle, so it may be the carb slightly off. I'll follow up after I get a chance to fool with it.
 
#12 ·
Ok, probably a stupid question. How do I tell if one of the weights flopped out of the channel? I didn't notice anything that looks different than the YouTube videos I've watched. No strange noises or rattles.
 
#13 ·
Update, it's definitely the clutch. The engine sounds great, but it is just revs high and the clutch is barely engaging. I'm going to inspect the wet clutch and primary when I get home. I'm guessing the guy may have flooded it and the water didn't get flushed out of the wet clutch at some point. I'll follow up after I get some supplies and take it apart.
 
#14 ·
Just so you know, your wet clutch is sealed from the rest of your cvt system and is bathed in your engine oil. That said it's certainly possible for the wet clutch pads to be warn out and cause the slipping you are describing.
 
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#15 ·
You’ll know because when you pull the grease seal cover off the primary one of the weights should be on its side under the cam. You mentioned about 200 miles, that’s extremely low to have wet clutch issues especially if you have stock tires. I have 1300 miles and 28” inch tires. I’m in the process of checking my wet clutch now and besides some oil burn there is still plenty of pad left. So all I’m doing is slugging it and lightly sand the burned oil off the pads. Not a hard process but more of a pain since it is internal.
 
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#16 ·
I'm sure I'll have some questions when I get in there. I saw a Caltric wet brake, seal and one way for about $100 on amazon. Has anyone tried them in the past? I put their carbs on my Grizzly 660 and Kodiak 400 and they have been great for several years now.
 
#17 ·
I have not heard any negative comments on the Caltric wet clutches.

But I will warn you. For the one-way bearing, do not use anything but OEM. Trust us on this. All others are garbage. This has been proven many times over. OEM or nothing for the one-way bearing.
 
#19 · (Edited)
I prefer not to get into get into the wet clutch if I don't have to, so I'm going to clean up my primary first and try it. I just need the 22mm socket and grease. The dealer changed the oil and it's looks lighter than I expected. I will drain it and make sure it doesn't have water/particles in it and stick with 10w40 yamaha oil. I'll follow up in a few days after I get the parts.

My engine braking seemed fine, so I'll stick with my oem one way. Thanks for the tip guys.
 
#20 ·
I read through this thread pretty quickly so I apologize if I missed something. From your original post, it seems like the miles and hours on your machine are quite low and you had good performance (other than the smoking). Do you know what oil your overhaul mechanic put in the machine? Maybe your wet clutch is slipping due to the wrong oil in the machine. If the oil he used after the rebuild wasn't wet clutch compatible, you may just need to change the oil. It seems that you had good clutch performance before the top end rebuild right? There are a lot more qualified mechanics on forum than I am, but I just thought I'd throw out this question before you tear it all apart.
 
#21 ·
You make a damn good point here....and one I should of noticed myself.
 
#22 ·
The oil change was performed by a large Kawasaki dealer, but it is a lighter brown than I'm used to seeing. I have everything off, so I will go ahead and clean up the primary and change the oil. From the comments here and reading other posts, I wouldn't think my wet clutch is my issue. I'll dig into it if cleaning the primary and oil change doesn't work.
 
#23 ·
I would change that oil to the yamalube just to be sure.I forgot what year you have, but my 06 450 told me when I put the wrong oil in. Immediately , as soon as I started it. It flashed me a code. I looked it up and it said I had the wrong oil in there to put in the wet clutch type oil. Changed it, light stopped flashing.
 
#24 ·
I should have the oil tomorrow. Waiting on amazon, but the oil, filter and grease all arrive tomorrow. Wishful thinking, but I think I should be set after I do the primary and oil change. If not, I have the sockets, grease, 10 quarts of oil, spare filter, extra plugs, etc. I hope this works anyways.
 
#25 ·
Well, I changed the oil and it had a weird green color to it. It didn't really smell like antifreeze and the guy that rebuilt it said the head gasket was good. I'm still at the full line, so i'm guessing maybe it leaked before the rebuild. I'm not sure, but it has fresh oil and filter now. I didn't see an water, but the last bit of oil seemed to have a dark liquid which I assumed was older oil mixed in. I cleaned up the primary and it sounds and looks good. It seems to run a little better, but it's struggling to hit 25-30 mph and it doesn't have nearly the low end response it should have. The carb is a bit off, so I'll play with that tomorrow. I could only test it for a couple of minutes, so it may need some time to break in or let that oil circulate. Any suggestions on the next move?
 
#26 ·
Run it for awhile, get it hot, put some mileage on. Then dump your oil again, see what it looks like. Watch your coolant level. Don't hammer on a rebuild. It needs break in to get proper seating of the rings. Running it up to full will break rings and glaze the new hone job. Then it will never get good compression. If you lose any coolant, or some shows up in the oil, you know were all your power went. Hard to imagine an expert would do a rebuild without changing the oil, even on a top end job. I'm suspect to how much was actually rebuilt. The clues are adding up.
 
#30 ·
My apologies if this was already done, but if it were me I would be considering checking my wet clutch at this point.
 
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#31 ·
Might as well, since I am going to change the oil again after I run it a bit. The primary was easy enough, but I need to read up a little more before I tackle it.

It ran perfectly normal except the clutch slipped on a steep hill after an hour of riding. I took it in and the dealer changed the fluids and checked the belt. The problem is my dad picked it up and he kinda leaves out some details. He just told me that the dealer showed him the clutch drain plug. I didn't see any signs or previous water in there when I did the primary. When I fired it up after that, it just smoked like crazy and then the power started dropping. The guy I took it to worked on the top end, but when I drove it to the trailer it didn't have the power it had, a plug wasn't plugged in so the diff limiter was kicking in (fixed now), the intake boot wasn't on correctly, the plastic choke screw was broken, etc.. I'm not sure if it was a sloppy rebuild or something else. Sorry for the long post, just wanted to give as much info as possible. Time to run it for a bit and then change the oil and hopefully check the wet clutch after some research. I appreciate all the tips so far.
 
#32 ·
I read this quickly and didn't see anyone mention a glazed belt. If I missed it sorry. Anyways. You might want to check out your belt before ripping into your wet clutch. If the side looks shiny or the side feels hard harder/slipperier then the top, That could be your problem
 
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