Honda ATV Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
17 Posts
Discussion Starter #1
Like the title says old yeller is smoking, but only on start-up otherwise runs perfect with zero smoke on acceleration or deceleration. The problem came up last year and I for-sure thought it was valve seals, I replaced valve guide seals with KW viton seals and absolutely nothing changed even though the original ones were totally fossilized. I know it is a dry sump engine so I drained the oil out of the crankcase and got quite a bit out, probably little more than a 1/2 qt . The smoking stopped....for a few rides and now is back. My theory is because of the high oil level in the crankcase oil get flung up onto the cylinder walls below the piston by the crankshaft when cold until it gets pumped back to the tank and the oil level falls below the spinning crank.
Is there a check-valve that prevents the oil in the tank from seeping back into the crankcase? Can overfilling the tank do it? I have never put more than 2 qts in after draining the tank and the crankcase.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #2
Like the title says old yeller is smoking, but only on start-up otherwise runs perfect with zero smoke on acceleration or deceleration. The problem came up last year and I for-sure thought it was valve seals, I replaced valve guide seals with KW viton seals and absolutely nothing changed even though the original ones were totally fossilized. I know it is a dry sump engine so I drained the oil out of the crankcase and got quite a bit out, probably little more than a 1/2 qt . The smoking stopped....for a few rides and now is back. My theory is because of the high oil level in the crankcase oil get flung up onto the cylinder walls below the piston by the crankshaft when cold until it gets pumped back to the tank and the oil level falls below the spinning crank.
Is there a check-valve that prevents the oil in the tank from seeping back into the crankcase? Can overfilling the tank do it? I have never put more than 2 qts in after draining the tank and the crankcase.
Bump?
 

·
Premium Member
Joined
·
43 Posts
Rhino, If the motor is stock, chances are that it is the rings. I have two of these, an 03 and 07 that were both stock when we bought them in the last year. The 07 we bought in December, was all original, and started smoking this summer. I did the same thing with new valves, seals, springs, everything the first go around because the piston and cylinder looked immaculate. It only fixed a bit of the smoking. Did the rings with just a hone on the cylinder and cleared everything up. Now it runs like a beast. The 03 we picked up this summer is starting to smoke a bit too and is getting harder to start. I’ll be doing the the head and rings on that one too. The OEM rings you can pick up from rockymountainatvmc.com for about $40 shipped. The honing only cost me $20 at a machine shop. As long as the piston and cylinder are good, you can get away with just that. While you’re in there, I would suggest having the decompression mechanism removed from the cam And have the oil passage for the decomp welded closed. It eliminates some of the ticking that mOST everyone complains about. The 07 has zero tick on it now.
 

·
Premium Member
Joined
·
43 Posts
Rhino, If the motor is stock, chances are that it is the rings. I have two of these, an 03 and 07 that were both stock when we bought them in the last year. The 07 we bought in December, was all original, and started smoking this summer. I did the same thing with new valves, seals, springs, everything the first go around because the piston and cylinder looked immaculate. It only fixed a bit of the smoking. Did the rings with just a hone on the cylinder and cleared everything up. Now it runs like a beast. The 03 we picked up this summer is starting to smoke a bit too and is getting harder to start. I’ll be doing the the head and rings on that one too. The OEM rings you can pick up from rockymountainatvmc.comfor about $40 shipped. The honing only cost me $20 at a machine shop. As long as the piston and cylinder are good, you can get away with just that. While you’re in there, I would suggest having the decompression mechanism removed from the cam And have the oil passage for the decomp welded closed. It eliminates some of the ticking that mOST everyone complains about. The 07 has zero tick on it now.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #6
Rhino, If the motor is stock, chances are that it is the rings. I have two of these, an 03 and 07 that were both stock when we bought them in the last year. The 07 we bought in December, was all original, and started smoking this summer. I did the same thing with new valves, seals, springs, everything the first go around because the piston and cylinder looked immaculate. It only fixed a bit of the smoking. Did the rings with just a hone on the cylinder and cleared everything up. Now it runs like a beast. The 03 we picked up this summer is starting to smoke a bit too and is getting harder to start. I’ll be doing the the head and rings on that one too. The OEM rings you can pick up from rockymountainatvmc.comfor about $40 shipped. The honing only cost me $20 at a machine shop. As long as the piston and cylinder are good, you can get away with just that. While you’re in there, I would suggest having the decompression mechanism removed from the cam And have the oil passage for the decomp welded closed. It eliminates some of the ticking that mOST everyone complains about. The 07 has zero tick on it now.
Thank you for the info but I don’t think it applies here. Like I said in my post, the smoking goes away completely when I drain the oil out of the dry sump and runs clean as a whistle and does not return for several rides. Pretty sure I’ve figured out the culprit, the excess oil is slowly leaking/weeping down from the oil tank when sitting. I think I’ve located the check valve on the oil pump parts diagram, Honda calls it a “leak stopper” VALVE, OIL LEAK STOPPER (15106-MG3-000)when you look at the microfiche. I’ve read about this cold start smoking problem now dozens of times over the past year and it has all the obvious signs of cold start worn valve seals which everyone has recommended replacing, which I did. I wonder how many valve seals/$ervice this “leak stopper” has sold.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #7
Rhino, If the motor is stock, chances are that it is the rings. I have two of these, an 03 and 07 that were both stock when we bought them in the last year. The 07 we bought in December, was all original, and started smoking this summer. I did the same thing with new valves, seals, springs, everything the first go around because the piston and cylinder looked immaculate. It only fixed a bit of the smoking. Did the rings with just a hone on the cylinder and cleared everything up. Now it runs like a beast. The 03 we picked up this summer is starting to smoke a bit too and is getting harder to start. I’ll be doing the the head and rings on that one too. The OEM rings you can pick up from rockymountainatvmc.comfor about $40 shipped. The honing only cost me $20 at a machine shop. As long as the piston and cylinder are good, you can get away with just that. While you’re in there, I would suggest having the decompression mechanism removed from the cam And have the oil passage for the decomp welded closed. It eliminates some of the ticking that mOST everyone complains about. The 07 has zero tick on it now.
The leak stopper is not the culprit, the saga continues........
 

·
Premium Member
Joined
·
43 Posts
I’m still leaning towards rings. since you have an 02, if they’ve never been done before,, and from the sounds of how crusty the valve seals were, it would be the most likely culprit. When it is cold, the rings and cylinder aren’t going to fit as tightly as when the motor is warmed up, allowing oil from the crankcase to get past and burn off. When you replaced the valve seals, did you have the valves lapped and clean up the seats?just replacing the seals isn’t going to do much if the rest of the valve train and wear items aren’t addressed. If you believe that the oil stopper is the cause, you may want to replace the spring also. If the spring is weak, it won’t allow the valve to close completely, allowing Oil or seep past. However, that is a pressure relief valve that returns oil to the tank if oil pressure gets too high at the pump, which would most likely be caused by a clogged filter and screen, or oil that is too thick. Try the rings. They are $38 plus shipping at Rocky Mountain. At the very least, if no one has ever done them before, you will eliminate the most likely cause.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #9
I’m still leaning towards rings. since you have an 02, if they’ve never been done before,, and from the sounds of how crusty the valve seals were, it would be the most likely culprit. When it is cold, the rings and cylinder aren’t going to fit as tightly as when the motor is warmed up, allowing oil from the crankcase to get past and burn off. When you replaced the valve seals, did you have the valves lapped and clean up the seats?just replacing the seals isn’t going to do much if the rest of the valve train and wear items aren’t addressed. If you believe that the oil stopper is the cause, you may want to replace the spring also. If the spring is weak, it won’t allow the valve to close completely, allowing Oil or seep past. However, that is a pressure relief valve that returns oil to the tank if oil pressure gets too high at the pump, which would most likely be caused by a clogged filter and screen, or oil that is too thick. Try the rings. They are $38 plus shipping at Rocky Mountain. At the very least, if no one has ever done them before, you will eliminate the most likely cause.
Thank you for the input, long reply here. More info: I bought the quad used 4years ago in very good condition from The second owner ($1600 !) who just had it a short amount of time and was going through a foreclosure and was selling everything....Also had a nearly new pristine Gold Wing at a bargain price as well which I really wanted but not worth a divorce.
According to this owner the original owner just had the engine done with 440/Hot Cams build right before he bought it. It runs like a raped ape.
I see no reason for him to lie considering it would have sold at that price stock to just about anyone breathing but I can’t say 1000% for sure what it has in it because I haven’t had the head off. Maybe the original owner could have lied but I can tell by looking at the bolts that it has come apart at one time.
Hasn’t seen a ton of use/abuse during my ownership (I’m a senior that has yet to grow up) and didn’t do the start-up smoke until last year, I mostly rode my WR450 (I just sold it before I ended up in the ER). When I drained the crankcase and put the oil back in the tank last summer the smoke went away for several rides(couple months) and returned this summer and doing the same procedure stopped the smoking but only for a month this time. I’ve checked the spark plug a dozen times and it is always a nice tan color with no burnt oil residue.
Is there a check valve that prevents the oil line to the cooler from draining back into the crankcase? I might pull it apart this winter and measure the bore size and evaluate it, It starts and runs perfect otherwise.
 

·
Premium Member
Joined
·
43 Posts
The oil stopper that you changed is the only check valve that I’m aware of. As for having a 440 kit and the stage 3 hotcams, you are in for a whole lot of other issues, depending on how it was done. If it is running a higher compression piston, the extra pressure tends to cause head gasket leaks and the stock head bolts to back out/blow out. They aren’t the most reliable, and there are better ways to make the same or more power much more reliably. Also, with that large of a bore, it seems to have too much of the cylinder removed which causes other problems. Chances are, with it bored to a 440, a previous owner did it either for bragging rights or because they rode the hell out of it. Either way, I would keep a close eye on it. You may also want to check the jetting on it. If it is running lean, it will wear out the piston, rings, and sleeve very quickly. I never trust a previous owners jetting. Many folks re-jet to the slightly lean side and don’t realize it. The motor will run great, but it will wear out very quickly.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #11
The bike is in cherry condition, many people can't believe it is a 2002, whoever was the original owner took very good care of it. If he rode it hard it sure doesn't show by its appearance even with the original tires. It has been rock solid for me for 4 years with zero problems(Honda) except for this mysterious come-and-go smoke. I ran it all last summer after draining the excess crankcase oil with no smoke whatsoever on start up or any other time. Always starts quickly even during 5 degree winter days to play in the snow, idles perfect, zero leaks. Came with nice spares.... filters-air and oil, new spark plugs, Honda service manual, new clutch in a package, billet levers, grips and new set of sprockets/chain, someone loved it. For $1,600 I couldn't get the money out fast enough. I jetted it for the 5K' when I got it and have a nice tan/brown plug and I've been jetting bikes since my 1968 Honda CL350. Even if it does need a top end after 4 years which I don't think it does, it was a steal. There is something going on with the dry sump being flooded with oil that is getting worse. Just went out and started it yesterday and nearly zero smoke because I drained the crankcase and put it back in the tank this weekend but I know it will be back in a couple rides. I need to find out why the oil is accumulating there.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #12 (Edited)
I didn't change the oil stopper, I realized when I studied the microfiche it was just a pressure relief.
I have also added a custom bracketed high flow brushless computer muffin fans to the oil cooler controlled thru the high beam switch with honda connectors (plug and play - no modifications to the OEM wiring) which I have a video of it pulling the oil temp down 20+ degrees. If this forum lets me I can dig up photos and post them, maybe someone might buy one. I made three complete units and was going to try to patent it but life got in the way. I was a R&D fabrication technician/engineering associate (overpaid tech or underpaid engineer....)for 33 years at a internationally known research laboratory designing/building/modifying research toys for scientists and am on several laser optical processing patents and in retirement still do design work on the side for a world renowned laser scientist for firearm/ammo money.
 

·
Premium Member
Joined
·
43 Posts
I’d like to see the fan setup. I have two 400ex’s for the boys. We are always working on something trying to get the most power and best tuning for them. So far both are bone stock except for an exhaust on one.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #14
I’d like to see the fan setup. I have two 400ex’s for the boys. We are always working on something trying to get the most power and best tuning for them. So far both are bone stock except for an exhaust on one.
Fit-up prior to paint and wiring. Pair of 60mm fans.
150889
150890

The pigtail goes in between the headlight to body connection. And I forgot I added a third 80mm fan mounted on those tangs to the left to blow directly onto the exhaust fin area.
I’ve got more pics somewhere but gotta do the nightly dog walk.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #16
Found a pic of the third fan and the type K thermocouple used to monitor the output of the cooler. What inspired this is my wife rides our Foreman a time easy pace which makes for slow going for the trx.
View attachment 150891
 
1 - 17 of 17 Posts
Top