Occasional Gas/Crankcase Smells

Think I probably found another part of the fuel/crankcase smell puzzle. The evap canister does not have free flowing air between the small intake pipe (from gas tank) to the large pipe (to purge control solenoid valve). It's clogged! Checking google, all the testing demonstrations showed free flowing air passing through the canisters, mine did not. Additionally, the smell from the canister was similar. At Honda direct replacement costs $150, ouch!

I'm having a similar problem to what you mentioned in your first post, and am starting to believe I have a canister issue too. Today my bike was hesitating/stumbling when riding slow in 2nd gear (1600-2000 RPMS), and hesitates when I roll on. It doesn't do it consistently, but is starting to do it more now. I have also had a strong gas/varnish smell when the bike is parked after riding, especially when it's hot like today. You can also hear the gas bubbling in the tank.

I first noticed the hesitating this morning riding through Woodland Park, CO (approximately 8600 ft), and it occurred more often near home this afternoon (approximately 6400 ft), but it was much hotter by then. I tried to find the canister location via Google and this forum, but no such luck. Unfortunately I don't have a repair manual, so I'm guessing the canister is somewhere under/near the fuel tank? Does it require major surgery to get to?

I also read on another thread that a member with similar issues to mine placed a heat shield between the "tank and the air cleaner," which solved his problem. These issues are new to me, and I typically only do minor servicing and repairs myself, leaving the rest for the dealer. Any help is much appreciated.

Thanks!
 
ST Dude said:
Think I probably found another part of the fuel/crankcase smell puzzle. The evap canister does not have free flowing air between the small intake pipe (from gas tank) to the large pipe (to purge control solenoid valve). It's clogged! Checking google, all the testing demonstrations showed free flowing air passing through the canisters, mine did not. Additionally, the smell from the canister was similar. At Honda direct replacement costs $150, ouch!

I'm having a similar problem to what you mentioned in your first post, and am starting to believe I have a canister issue too. Today my bike was hesitating/stumbling when riding slow in 2nd gear (1600-2000 RPMS), and hesitates when I roll on. It doesn't do it consistently, but is starting to do it more now. I have also had a strong gas/varnish smell when the bike is parked after riding, especially when it's hot like today. You can also hear the gas bubbling in the tank.

I first noticed the hesitating this morning riding through Woodland Park, CO (approximately 8600 ft), and it occurred more often near home this afternoon (approximately 6400 ft), but it was much hotter by then. I tried to find the canister location via Google and this forum, but no such luck. Unfortunately I don't have a repair manual, so I'm guessing the canister is somewhere under/near the fuel tank? Does it require major surgery to get to?

I also read on another thread that a member with similar issues to mine placed a heat shield between the "tank and the air cleaner," which solved his problem. These issues are new to me, and I typically only do minor servicing and repairs myself, leaving the rest for the dealer. Any help is much appreciated.

Thanks!
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The stumbling is a sign of a failing fuel pump, especially if the problem amplifies the more heat-soaked the fuel becomes (the later in the ride you are) and if it calms when refilled with cool fuel.

The canister may be obstructed too, plugged but that isn't much of a player in the stumbling. When the fuel canister is plugged, the tank can develop a slight pressure inside it--that pressure actually slightly aids a failing fuel pump.

The canister is in front of your right shin. Right side Tupperware has to come off (which means certain inner fairing pieces by the radiator, the rear view mirror cover, and the lower black cowl have to come off first). Search for Tupperware removal threads.

The boiling sound in the tank is normal and will occur when the fuel is warmed--some of the fuel constituents (especially ethanol) is especially prone to boiling at elevated altitudes (Colorado!), especially when warmed. It does not indicate a problem.

Any heat shield is not sufficient to overcome a failing fuel pump.

You really should find a factory service manual--best $40-$50 farkle you can get for the bike. ;)

Hope this helps.
 
ST Dude said:
I'm having a similar problem to what you mentioned in your first post, and am starting to believe I have a canister issue too. Today my bike was hesitating/stumbling when riding slow in 2nd gear (1600-2000 RPMS), and hesitates when I roll on. It doesn't do it consistently, but is starting to do it more now. I have also had a strong gas/varnish smell when the bike is parked after riding, especially when it's hot like today. You can also hear the gas bubbling in the tank.
Click to expand...

You can easily check the evap canister by bowing air into the canister intake tube from the gas tank and see if air is passing though it. If not, it could be plugged. The service manual describes the different tubes which I no longer remember. By your smell description it could be a problem, but at $150 dollars I'd check before dropping a new one in.

BakerBoy said:
The canister may be obstructed too, plugged but that isn't much of a player in the stumbling. When the fuel canister is plugged, the tank can develop a slight pressure inside it--that pressure actually slightly aids a failing fuel pump.
Click to expand...

+1 My problem was from idle not second gear. Never hesitated from second. It would die while idling indicating a 5 way-T problem or throttle body sync issue. Those problems of mine are solved now.
 
Reginald said:
You can easily check the evap canister by bowing air into the canister intake tube from the gas tank and see if air is passing though it. If not, it could be plugged. The service manual describes the different tubes which I no longer remember. By your smell description it could be a problem, but at $150 dollars I'd check before dropping a new one in.

Thanks Reginald. After input from BakerBoy and some more research, I ordered a new HFP-382 fuel pump from Amazon via HFP Fuel Systems. I also talked to Junior at HFP, and he said the pump on Amazon was the same as the one they sell specifically for the ST 1300 (HFP-382H-S15), the only difference is you get more filter socks with the one I ordered. It was $59.98 with free shipping.

I'm supposed to get it towards the end of next week, so I'll report back once it's installed.
Click to expand...
 
BakerBoy said:
The stumbling is a sign of a failing fuel pump, especially if the problem amplifies the more heat-soaked the fuel becomes (the later in the ride you are) and if it calms when refilled with cool fuel.

The canister may be obstructed too, plugged but that isn't much of a player in the stumbling. When the fuel canister is plugged, the tank can develop a slight pressure inside it--that pressure actually slightly aids a failing fuel pump.

The canister is in front of your right shin. Right side Tupperware has to come off (which means certain inner fairing pieces by the radiator, the rear view mirror cover, and the lower black cowl have to come off first). Search for Tupperware removal threads.

The boiling sound in the tank is normal and will occur when the fuel is warmed--some of the fuel constituents (especially ethanol) is especially prone to boiling at elevated altitudes (Colorado!), especially when warmed. It does not indicate a problem.

Any heat shield is not sufficient to overcome a failing fuel pump.

You really should find a factory service manual--best $40-$50 farkle you can get for the bike. ;)

Hope this helps.
Click to expand...


Stumbling/hesitation issue follow up. I have 303 miles on the new fuel pump I installed last month, and it's definitely got more power now. I thought the decrease in power was only due to the altitude change (moved from Oregon to Colorado to attend Bible college in 2011), but it must have been failing for a while. The gas/varnish smell is also gone, so I'm happy about that.

The low RPM stumbling improved but didn't go away completely, so I added some BG 44K to the tank. That seemed to help a little too, but I had another stumbling/hesitation episode today. On my way home I stopped at Whole Foods to pick up a supplement, and the bike was running pretty good. I come out 5 minutes later, ride off and it stumbles a little. As I ride home it seems to go away as I'm keeping a close eye on the RPM stumble zone. I get to my neighborhood, ride a little more to see if it repeats, and sure enough it starts stumbling again at low RPMs (1200-2300). Not fun when it does it in turns.

I called the local Honda dealer and the service writer said it could be the failing fuel pump caused an issue with one of the spark plugs, and indicated they had seen that before. I know he's a writer and not a wrench, but I'm willing to consider anything at this point. I'm going to order a service manual tonight as I found a PDF version for cheap. I don't know much about vacuum hose or throttle body issues, you all have any other thoughts?

Thanks,
Travis
 
Travis,
Off the top of my head, potential other sources of stumbling (besides fuel pump), generally arranged in order of most likely to least likely (my opinion only):
  1. plugged or leaky vacuum line(s) between throttle bodies
  2. leaking throttle body insulators (the rubber boot between each throttle body and cylinder intake)
  3. partially seated spark plug wire(s)
  4. poorly made connection in a wire harness somewhere
  5. spark plugs
  6. marginal rectifier on alternator (doesn't maintain voltage well when picking up load from battery)
  7. cam timing sensor)
 
BakerBoy said:
Travis,
Off the top of my head, potential other sources of stumbling (besides fuel pump), generally arranged in order of most likely to least likely (my opinion only):
  1. plugged or leaky vacuum line(s) between throttle bodies
  2. leaking throttle body insulators (the rubber boot between each throttle body and cylinder intake)
  3. partially seated spark plug wire(s)
  4. poorly made connection in a wire harness somewhere
  5. spark plugs
  6. marginal rectifier on alternator (doesn't maintain voltage well when picking up load from battery)
  7. cam timing sensor)
Click to expand...

Thanks for the response BakerBoy. I went out to see how difficult the plug change would be, got one plug wire off and eventually reseated, then started the bike. It started much quicker than it has been, so I let it run for a little bit. I then decided to make sure all plug wires were properly seated and heard and felt a faint click on the #1 cylinder plug wire.

I started it again and it fired right away, so I slowly revved it through the typical "stumble zone" up to 3,000 RPM, and it seemed improved. I also noticed the strange exhaust gurgling (like it's stumbling) at 3,000 RPM was greatly diminished too. The dealer changed these plugs at the 16,000 mile service (about 3,000 miles ago), so the tech apparently didn't seat that one fully.

I'm not sure if that could/would have damaged that plug, but I'll hold off on new plugs for now. I'll put it back together and ride it tomorrow to see if that fixed it. Fingers crossed.

Thanks for the recommendation on the service manual too. That's going to be a must with every motorcycle purchase from now on.
 
BakerBoy said:
The boiling sound in the tank is normal and will occur when the fuel is warmed--some of the fuel constituents (especially ethanol) is especially prone to boiling at elevated altitudes (Colorado!), especially when warmed. It does not indicate a problem.
Click to expand...

An ahhh hah moment. Does this mean we can make ethanol free gas by boiling a few gallons on the kitchen stove?:bow1:.

Don't try this in your own home.
 
Bringing to life old topic =)

I also having weird gas smell on my Pan European. Riding regime seems does not matter, will pay more attention.
My first thought was EVAP is cause..

However - EU version seems have no EVAP canister in stock, at least not only mine.
If provision above is accurate - reason could be somewhere else.

UPD
Checked OEM Parts Diagram
EU versions indeed comes without EVAP canister both before and after 2008.
 
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