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    Colorado Springs, Co.
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  1. Yup. No joke. When you shut the ATV off you can hear it and when you remove the gas cap you can see it bubbling around the fuel petcock. Yes it is bizarre I've never experienced it before either. And in this one summer I've had it happen in two of my vehicles that are completely stock. I've been a mechanic on one thing or another from Machinery to aircraft and been working on vehicles since I was about 10 years old and this is a first. I'm telling you the world's coming to an end.😜 Darrell
  2. The tank is in the stock location...right above the engine and exhaust. I haven't heard of methanol being used in fuel the ethanol yes. I'm not sure to what degree I just haven't paid attention. I do know there's a couple of gas stations here in town that claimed to have pure gas but I think their specialty commercial type gas stations. And yes I am going to do some kind of extra heat shielding to keep the exhaust from radiating upward towards the tank as much. Darrell
  3. It's not just the elevation but a combination of things. After the boiling issue persisted for a couple hours in all of the slow, steep, rough stuff where the engines were making lots of heat and very little airflow and a hot day once we picked up the pace for a mile or less everything went back to normal and didn't rear its head once over the next 3 days. Since it happened to two different machines one Rubicon 1 Rancher 1 carbureted one fuel injected. Fuel purchased from two different stations. Only persisted for about 3 hours on one very hot day I'm 99% sure that it was just that everything was very hot. The fans were constantly turning on and off but I never got a overheat light in my friends Rancher has a aftermarket digital dashboard with water temperature and he said it never got very hot. Whatever he meant by that I'm not sure. My original intent for this post what's to see if anybody else had experienced this, which it seems no one so far has. And what they may have done to remedy it in the long run if it was a persistent problem. I am going to create another exhaust Shield just to give another layer of protection so it doesn't happen again. There doesn't seem to be any effect on performance it was just something I noticed and was wondering if it was common. I do appreciate all of the different comments, ideas and their discussions. Darrell
  4. Anything's possible and that's a possibility but I doubt it's water. If it was water and ethanol the water would mix with the ethanol and the ethanol would mix with the gas. Plus I run Heat in my tank every once in awhile to make sure there's no water in it. As well as the fact I have removed and drained the tank completely and there was no water to be found. I saw the same data as you for gasoline having a boiling point from 100 to 400 degrees. but found more data that said that Automotive gasoline is around 185 degrees Fahrenheit boiling point and I assume that's a standard temperature and pressure. So I extrapolated a little bit and figured that it may be around 175 degrees at the altitude I was at. Probably less actually. But again depending on the ethanol and octane mixes that could change the boiling point. I don't know what gasoline boils at 400 degrees but it certainly isn't anything you're putting in your car. Today's modern fuels are much more volatile than the stuff that was around in the 60s and 70s and even into the 80s which is why so many older carbureted vehicles have Vapor locking issues since the 80s. I remember dealing with this a lot in the 80s and 90s in carbureted Vehicles when the fuels were changing so much. Darrell
  5. Yes you are correct. But there are better materials and better ways to go about blocking / reflecting the Heat. Since you can't actually see the petcock with the fuel tank installed you'd never know if your close Pin or whatever was still in place plus the plastic shield underneath is so closely fitted to the fuel tank I don't think there's any other room for something so big. Once I get it back together I'm going to create a better exhaust Shield that should do the trick. The real Puzzler is this is the first time I have ever had this problem with any gas powered vehicle I can remember. Darrell
  6. That's funny you mention the wooden clothespins. I do carry those in my toolbox in my truck for the guys who are still carbureted and have vapor lock problems it really does help. But I didn't have a vapor locking problem. Just a fuel boiling in the tank problem. Now that you bring it up I suppose there is a possibility that the rubber fuel line from the petcock to the carb was getting extra hot and Vapor was traveling back up the line into the tank but I do kind of doubt that theory since rubber does not transfer heat as well as metal. Darrell
  7. I don't know if the petcock was scorching hot you can't actually touch it on the Rubicon. The exhaust is almost directly below where the petcock is with only a small partial exhaust Shield and then a large plastic shield just underneath the tank. Not sure what you're referring to with the pump cavitation the 2003 is a gravity-fed carburetor. And my friends Rancher that is fuel injected did not have an operational problem ( neither of us did )just gas gurgling in the fuel tank just like mine. And yes I'm aware that altitude, heat, barometric pressure, octane and alcohol concentrations in the fuel will all affect the boiling point. Just wondering if anyone else has ever run across this issue. Darrell
  8. Hi everyone I came over to this site from the other Honda ATV site that it seems some of the more knowledgeable and experienced guys on here came from. I live in Colorado Springs Colorado I'm semi-retired I have a 2003 Honda Rubicon a 2002 XR400 a 79 Scout II and a couple other unremarkable vehicles. I spend most of my time hunting, fishing, shooting, 4-wheeling and camping around Colorado and Utah. Darrell
  9. Yes it was definitely venting. Plus when you took the gas cap off you could look in and see the fuel boiling around the petcock. And like I mentioned it wasn't just mine that was doing it my friends was to. Definitely odd. I don't know if it's just the gas that we have here in Colorado. Right now in the super hot summer I have got a completely stock '90 Mustang that I have had gas bubbling out around the gas cap this summer when I run the AC when it's real hot and that never happened when I lived in Phoenix and it was a 120 degrees and we've only been hovering around 100 here in Colorado Springs. Darrell
  10. Honda OEM Parts all the way I stay away from Chinese crap. I ordered everything that had to do with the sprag clutch because there are no specifications as to service limits. And there was no smoking gun as to the reason for the problem. So since everything looked fine but something was wrong and the last thing I wanted to do was save a few bucks and have to tear it back down again because I didn't replace one part. I'm replacing the clutches because all I have is a minimum Dimension out of the maintenance manual but not a maximum so I don't know how much I've actually used over the years in friction material. And I'm replacing the Springs just because they're cheap. You're right I likely purchased more than what I actually needed but to me not having to tear it down again for the same problem is worth a few extra bucks and this way I shouldn't have to do it ever again. I'm the type of mechanic that believes and doing it right the first time, if it's questionable replace it especially if it's something that requires a lot of time or effort to get to. Likely I could have just replaced the sprag clutch and the drum since the drum bushing was out of spec. Darrell
  11. What a coincidence I just did my steering bushing last night. Yes you are supposed to grease them it's in the Honda manual. While I had the whole thing apart i checked the clamping Force that would be applied to the bushing if you clamped it tight and it would definitely deform the bushing. So once I got it all back together I first clamped everything down and tested the steering snugness then I put a shim on one side that is probably a 16th of an inch in thickness and I can torque the bolts down snug so they don't come loose and it definitely allows for a lighter steering feel without the shaft being sloppy in the bushing. Darrell
  12. That's the odd thing about it. Yes I did inspect the drive plate the drum and the sprag clutch. And other than a very slight amount of bluing on the drive plate Hub where the bearing rides nothing has any galling, flat spots, blueing, chattering, shiney spots or anything out of the ordinary and by hand the clutch does not turn backwards in the least but apparently it is slipping with the weight and Torque from the ATV and the Driveline. I have ordered all three new parts make sure everything is back to factory spec as well as Springs and clutches even though they're good just so I know I'll never have to mess with it again. Darrell
  13. Hey all hope this finds everyone well in these weird times. The Rubi has been running and operating perfectly for the last 2-3 years so I haven't been to active here. Long story short 3 or 4 years ago the engine was rebuilt with a new crank and Hondamatic...yes a new Hondamatic not used or reworked. My problem is during deceleration in 1st gear at slow speed like going down a steep hill on a trail the engine looses engine braking at 6mph. Anything above that and the centrifugal clutches stay engaged but below 6, I am guessing this is the 1st gear input rpm where the flyweights keep the clutched engaged, and below 6 is where the springs pull the weights back in. the ATV acts like it's in neutral. I also get a rattling sound when the clutches disengage. If I keep the speed over 6 in 1st I keep engine braking, if I drop below and the clutches (seemingly disengage) and the speed picks back up to over 6 the rattling gets worse but no engine braking but if I rev the engine to engage the clutch I get engine braking back again. Shouldn't the sprag clutch keep the engine braking going as long as the drive-train at the input to he Hondamatic is wanting to turn faster than the engine idle rpm? Also the faster I go RPM wise like in 5th gear I get a gear whine, it sounds exactly like straight cut gears that are out of alignment ( where you get higher rpm as well as load on the gear train.) So to me it sounds like the sprag clutch is slipping which would explain the loss of engine braking and the rattling sound. Also I figured the bushing in the clutch drum, the bushing that rides on the new crank surface was out of spec it would allow the gear to cant and cause the out of alignment gear whine I was hearing. So I figured I new what was wrong, but to my surprise when I tore the front of the engine down everything seemed fine...the sprag clutch works perfectly and immediately the clutch drum bushing seemed fine but during mic'ing the bushing is out .003 . 2003 Rubi. Any ideas? Darrell
  14. You read that right the fuel is boiling in a plastic tank. You can hear it and you can see it. Anyway after riding on some steep very slow trails (1st and 2nd gear) at about 80-85 deg and about 9500 ft the fuel will start to boil in the tank, I had this problem and so did my friend with a 2006(?) Rancher. You can tell the fuel is boiling at the petcock. All of the engine/exhaust shielding is in place on both machines. I am assuming the exhaust heat is being transferred to the fuel by the metal of the petcock. I am guessing that gas boils at about 173 deg (at 9500ft) depending on octane and methanol percentages it may be less. Has anyone else experienced this? What have you done, if anything to remedy this? I am planning on some type of extra shielding but haven't decided on what exactly. 2003 Rubi. Darrell
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