Fuel in oil, but float valves working

[SC_Valkman]

I have a 1997 GL1500C, and took it out for a ride a couple of months ago, then parked in garage on side stand.  Next day, went out and noticed oil on floor.  Troubleshooting steps to date:
--Traced it back to rear crankcase overflow hole.  
--I checked dip stick and it was over filled.  
--I drained oil and noticed it was thin and smelled like gasoline.  
--I checked the petcock valve and it stopped fuel flow.
--I noticed petcock vacuum flow control system, so I checked if fuel leaked past diaphragm but hose was dry.
--I read about hydrolock with float valves stuck open, so drained all gas out of bowls refilled to flush debris out of float valve.  Refilled oil, but fuel contamination returned.
--Figured worst case, so removed carb assembly and performed bench float test consisting of attaching hose to right bank of 3 carbs in upright position, then blow to see if little to no resistance.  It passed air, so I assumed all 3 floats passed the air.  Repeated on left side, with air passing.  In order to replicate the float bowls filled with gas and closing, I then inverted the carb assembly  and performed the same low pressure tests.  Both banks would not allow air to flow, so they were closing as expected.
--Assumed that debris must have worked free, so I put carb assembly back on bike along with air filter, tank, added oil, and took out for test ride.  Fuel contamination problem was still there.
--Thought maybe I could see which carb was culprit, so removed the 6 risers and checked for fuel drips with the petcock open.  Since vacuum actuates petcock, I applied my vacuum tester at - 20PSI so bowls filled up but still no drips.
--Thought about water contamination, but that usually turns the oil color and texture into something like a milkshake but this oil looks good other than the really thin viscosity.  I thought about hydraulic fluid, but the brakes and clutch reservoirs were full.
--Left petcock open for 2 weeks, still no drips so reassembled and filled with oil and took test drive.  Fuel contamination in oil returned.
--Assumed float valve(s) still stuck open or debris returned, so I pulled the carb assembly off (again), removed each bowl at a time, but none showed any debris and looked relatively clean.  There was a slight amount of thickened fuel left in jet cavities, but that should restrict flow.  Repeated bench float test and all closed inverted, and then opened when returned back to upright position.  I consider the float valves are OK.
--The fuel enrichment (FE) valves used for the choke system could add extra gas, but each one returns to its fully seated position after you open it.  I consider the FE valves are OK.
--Since problem occurs while engine running, I thought maybe the main jet needle valves were getting stuck open.  Unfortunately, the metering rods all seem to return back to the full down position.  The throats of the carbs were clean with no debris.

I plan to disassemble each carburetor, dip them in carb specific cleaner, and then blow dry, but my fear is I don't see the "smoking gun" problem and all the work will be for not.

Besides the petcock valve and the carbs, is there anywhere else fuel could get into the crankcase oil?   Because going to the shop will not be cheap plus I would like to figure this one, I appreciate any help.

[Daniel Meyer]

Man, that's a weird one...

When you apply a vacuum to the petcock, does it hold?

Any chance that somebody hooked a vacuum line to the tank vent?

Air filter okay? Could extra fuel be getting sucked up into the airbox (could then drain into the crankcase via the vent hose). I would think the drool tube would be full then though....

[SC_Valkman]

When I put negative PSI to petcock vacuum control, it holds steady so I assume the diaphragm is intact and holding.

The vent tube to the tank is clear and runs to the lower part of the frame where it picks up air.

I also thought about that crankcase vent  in the air filter, but no sign of fuel in there.  Not really sure how it would get there, but I'm grasping at straws so checking out all possibilities.

I started disassembly of my 1st carb, when I noticed needing a special pilot screw wrench.  The service manual gave me 2 options for part numbers.  07VMA-MN50100 or 07MMA-MV9010A (USA only), so I'm assuming I'll need the second one.  I'm getting to know (and spend) more about this motorcycle every day.

I appreciate your inputs.

[Daniel Meyer]

A weird one for sure...anything passing enough fuel to visibly contaminate the oil should be very easy to spot...

Carb overflow tubes (there's two of 'em...stick through a bracket in the center of the engine, open to air) okay? Not hooked to something wrong?

[SC_Valkman]

You'd think it easy to spot such an obvious gas leak, but I have tendency to get difficult problems with my vehicles.

I don't see any carb overflow tubes, so I'm assuming you meant the air vent tubes.  They just go through holes in the rear stay plate that holds the carbs together.  Those tubes end about 2 inches past the stay plate.

The O-rings for the fuel rail and that air vent are making it tough to pull the 1st carb off, so I can see why they suggest replacing them.

[Ricky-D]

I feel there is too little attention being given to the fuel petcock.

Having the petcock in the "off" position is, at times, very chancy.

Especially so, if the accessory handle is not in correct alignment.

***

[al v]

Fuel in the #6 vacuum line to the petcock?

[Regis]

you may be able to pull off the plugwires from the plugs after it has sat overnight , crank it over a few times without giving it throttle , then pull the plugs and look for a wet 1 to narrow down which carb is bypassing . Not saying this will work but I would try it .

[SC_Valkman]

I removed the petcock valve a few minutes ago and did another fuel flow test, which showed the vacuum control was not stopping the flow when no vacuum applied.  I opened up the diaphragm area, but nothing seemed amiss (no holes, wrinkles, etc.) so cleaned and carefully put it back together and tightened the screws.  By blowing on the output tube, it now stopped flow until a vacuum was applied.  This means I can stop my fuel flow after riding or when the engine stops, but does not explain why gas gets in the crankcase when the float valves should stop fuel flow when the bowls are full.  It's a gravity fed system, so these valves don't have to handle much.  When I blew into them upside down, they seem to seal quite well and released when turned back right side up.

While draining the gas out of the tank sump area, it was not pretty (cloudy, debris, etc.) plus the carbs have a little build up in the bowls so I may be having intermittent sludge or small debris getting in the float valves.  I'm this far into the job, so I'm going to dip them into solvent, blow them out with compressed air, re-assemble, and hope I've got it solved.  

I have the 1st carb torn down to everything but the pilot screw, which requires a special wrench p/n 07MMA-MV9010A or could have been superseded by 07KMA-MN9A100.  The cost ranges from $275 to $114, while one person claims a 22 shell casing bent into the D shape fits.  This sure is an expensive wrench, so if anyone knows these numbers will not work please respond.  It may be a week before I get the wrench, so may not hear from me in awhile.  I really appreciate everyone's inputs.

[Daniel Meyer]

Try testing the carbs with fuel...at about the angle when your bike is on it's side stand. Whole different animal than air and upside down.

On the "D" wrench...there are instructions somewhere on how to make some tool into one...do a search...maybe one of the carb guys will chime in with it..

[Patrick]

Pilot wrench ? One can be made out of tubing, such as, something like auto antenna or tubing. Then once the screws are out, a slot can be cut in them for a screwdriver.

Fuel could run from the petcock thru the vacuum line to #6 cylinder. That bypasses the carburetor. The problem as I see it though is that much fuel would lock that cylinder.

[Denny47]

You can order the pilot stubby tool off ebay or from www.redeye.ecrater.com. Cost is about $6

[Thunderbolt]

Sounds as if you have/had a problem with the petcock.  I'm with Patrick, if that much fuel were flowing down the vacuum line I would think it would hydrolock.  I always use a temporary fuel container, I have an old lawn mower tank with a hose and cutoff in line to test the carbs.  I would try that this time before re-assembly.  That way you know for sure the floats are not leaking.  I was always hesitant to change from the OEM petcock, kept rebuilding them until the third time.  Finally went with the manual Pingle, I think the number was 6211CH, but check that if you decide to change.

[SC_Valkman]

Thanks for all the possible ways to make or buy a pilot tool.  I have several sizes of tubing, so definitely going to try that first.  The vendor for the $6 tool is on a business trip with a return date of 08:02:2013, so if the tubing mod doesn't work then he's next on my list.  I like the idea of putting a slot in the head, so I can use a flat screw driver.  My thin cutting blade on my drimmel tool should do the trick.

As for the bench flow test, the 1st time the carb assembly came out I used a funnel on the end of the line.  The float valves worked great, so that's why they went back in.  By the way, air viscosity is much thinner than gas so I would assume if the float valves stopped air it would certainly work on gas.  Not sure if flotation force is greater than gravity, so never hurts to try the test with real fuel.

The #6 cylinder vacuum line seemed like the obvious problem, but dry as a bone.

Since the petcock seems to intermittently work, I may go ahead and invest in the pingle if this persists.  Put everything away an hour ago, so off to the parts store tomorrow for the carb solvent and then back at it again.

I appreciate all the help.

[SC_Valkman]

You can order the pilot stubby tool off ebay or from www.redeye.ecrater.com. Cost is about $6

I received email back from Rich Byrne of Red Eye Tech Services that he's back from his trip, so I ordered the full carb assembly O-ring set and the pilot screw stubby tool.  He was quite reasonable on the prices compared to all the Honda dealers.  Most of my O-rings for fuel and air were stiff and a couple had cracks, so definitely needed replacement.

I was hoping one of the carbs would look suspicious, but they all looked pretty clean prior to the dip into the solvent.  I even took the crankcase breather reed valves apart, but they were all seating.  Tube from the #6 cylinder area was a little dirty, but reed seated flush so just cleaned it.

Rich said I should have my parts by Thursday or Friday, so sounds like a weekend project.  May be able do a test drive by Sunday.

[Denny47]

Have ordered a couple of times from Rich and always happy with service. Prices are good and shipping is most reasonable that I have found.

[ryord]

 I have a 2001 Valkyrie Standard, I rebuilt the carbs with the help of a friend in Topeka Ks. I had intermittent leaks from the fuel rails so we replaced all o-rings and assorted parts from Redeye"s carb kit that you ordered. I also had intermittent problems with the petcock, from reading and studying the board here I replaced mine with a Golan manual petcock, I have not had one problem with the bike in almost 2 years. The carb rebuild and manual petcock work great. Good luck.

[pancho]

Look, you cannot get enough fuel through a carburetor to overfill and contaminate the oil without getting a lock issue.....   I wonder about the presumption that there is fuel in the oil, how are you verifying this?? you mentioned the viscosity, but gave no evidence  that fuel was responsible for changing it.

You are doing a lot of work, but I wonder if you are barking up the wrong tree..

[SlowRoad]

When  I first bought my 97 standard, I had an issue of fuel leaking into the crank case.  Bike had been sitting for 6 years and only had 4500 miles on it. I almost ruined the engine before I spotted it.  Gas and oil running out the tail pipes at idle trying to warm it up to check it out!!  But it never locked. 

On the other hand however, 8 years later I currently have the engine out of this same bike due to not turning  off my manual Pingel petcock while I had lunch and had a hydrolock that broke the starter idler gear. I will be installing a Dan-Marc electric fuel solenoid before the engine goes back in.

I have left the petcock on for short periods a hundred times and never had an issue.  This was the time that it was and issue.  So be careful turning the engine over with gas leaking into the engine until you do track it down. 

Just my $.02

[98valk]

constant/many short rides whereas the oil never gets to at least 200F will build up fuel in the oil.
do u like to blip the throttle at red lights? more raw fuel being dumped past the rings.
do u like to blip the throttle right before u shut the bike off? more raw fuel going past the rings.
if the bike has been sitting for a few days/wks do u like to go start the bike and run it for 10 minutes? just to charge the battery? an alternator is not meant to charge a weak battery. more raw fuel into the oil, which never gets up to temp to burn it off.
when is the last time u had your smelling tool calibrated for PPM of fuel? 

[Ricky-D]

Look, you cannot get enough fuel through a carburetor to overfill and contaminate the oil without getting a lock issue.....   I wonder about the presumption that there is fuel in the oil, how are you verifying this?? you mentioned the viscosity, but gave no evidence  that fuel was responsible for changing it.

You are doing a lot of work, but I wonder if you are barking up the wrong tree..

Yep,,,,,,, I agree with this.

Although there could be some bad rings on a piston that would let a lot of gasoline pass into the crankcase.

Starting to do a lot of work, that may be unnecessary, is foolish in light of the cause of the problem remaining undiscovered.

***

[SC_Valkman]

As for barking up the wrong tree, that is why I laid out my diagnostic steps, results and thoughts.  I'm open to suggestions.

Why did it not hydro-lock?  Good question, but it started up fine and I enjoyed driving it about 10 miles with up to 70 mph on an open road.

Am I sure its gas?  No, but through process of elimination between hydraulics and cooling water its the only thing left.  With the strong smell of gas, lubrication seemed less (rubbing oil between my fingers) and gas will mix with oil, I have a strong hunch that is what is in there.

Am I sure its really leaking into the crankcase?  Yes, you do not gain a 1/2 inch on the dipstick.  Measurements were taken at the same spot in an upright position, before and after driving.  If it comes up too much more, it will start to come out of the overflow hole on the back of the crank case.  

Could it be a stuck ring passing the gas?  Not sure, but wouldn't most of it be consumed during the combustion cycle?  You usually feel a power loss, but the bike seemed to have good torque so I'd not suspected a stuck ring.  I'll have to put the compression gauge on the cylinders.

Rebuilding all the carburetors seems like a big job, if you do not know that is the problem.  Trust me, it was the last thing I wanted to do.  I thought I'd exhausted all my options, so I wanted to open up one of the carbs and see if they had an overflow hole and where it went (possibly the crank case?).  They just go to the air rail, which the tubes terminate on the carb frame.  If the gas were to overflow, it would just dump out on to the top of the crank case but not into it.  After doing the 1st carb, it was no big deal to do the rest plus I could give them all thorough inspection.  The O-rings on the fuel and air rails were definitely needing replacement (cracks), so I'm just out $65 for the whole carb assembly kit from Rich Burns at www.redeye.ecrater.com and I learned a lot more about my Valkyrie.  

I get my O-ring kit this Friday, so I plan to bench test the whole carb assembly with the fuel tank before going on the bike.  Plenty of wood and spare rubber hose, so I'll build a test fixture to hold the tank above the carbs plus I'll use my vacuum tool to replicate the suction of the engine on the petcock valve.  If things check out, then its on to the bike and all those fun extras like synchronizing the throttle valves and pilot screws.

I like tinkering with things, so rebuilding, synchronizing and calibrating the carbs will not be a big deal but don't want to do it again for awhile.  I appreciate any suggestions, so if you think carbs is the wrong tree then please tell me which tree.

[pancho]

You may be barking up the wrong tree, but like you said, you are learning a lot about your bike and going through the carbs and syncing them can do nothing but good as long as it is all done properly.

As long as you have not removed the piston rings from your motor, I can assure you that your crankcase is not filling up with fuel due to a leaking needle valve in a carburetor. What is causing your problem?? You seem to be an able enough mechanic to do the proper diagnostics........  I'm just not sure that the assumptions you are going with at this time are sound. I for one cant help point you in any direction right now,, you need to get your carbs back together, installed and get back on the road. Then maybe start over from ground zero. I am by no means criticizing your efforts,,, I just think you got off in the wrong direction before you knew which way to go.

[bulabula]

I hope you get this sorted out and let us know what happened...

How many miles on the engine?  Does it smoke or burn oil?  What are the oil change intervals?  Are you the original owner?  Do you know the maintenance history well?  Sorry for the questions.

I can't see how a bad gas petcock is the problem since the engine fills up when running.  Petcocks are supposed to pass gas then....  I would suspect leaking needle valves in the carbs if it filled up overnight, but not necessarily if it happened when running (and a bad petcock).

SWAG:  Are all the spark plugs the same color?  What color are they?

It seems that some of the guys are pointing towards bad piston rings?  A half inch oil level rise in one ride seems to be a lot of gas being pulled into the crankcase.  Maybe you should do a compression test and leak down test.  Might be easier with the carbs off too.

I only think about wetstacking with my diesels (prolonged idling in cold weather), and not with my gasser engines.  I don't think thats the issue with yours, but someone asked about your riding methods.

Again, I'll be watching this thread to gain more knowledge on these bikes.

[Rio Wil]

You said oil was leaking from the rear crankcase overflow hole......I am not aware of this hole, can you be specific as to where it is??


Also, I have to ask........you mentioned the oil level was up a half inch.  did you check the oil with the bike upright and the did stick NOT screwed in?......sorry just have to ask......

[SC_Valkman]

Well, I received my O-rings early but tied up with another project (starting a homebrew beer batch) so limited what I can do today.  I read an article the other day that alcohol can actually improve cognitive reasoning, so I may have to give it a try.  I'm a pretty fair mechanic with building up hotrod cars, 4WD trucks and a couple of bikes over the years but this one problem is illusive so it’s become a challenge to overcome.  Tell you the truth, I have to wonder if I made a wrong turn and did not realize it so I’m in agreement with Pancho to get it all back together and start again.

Still on my to-do-list before starting over:
1)    Compression test cylinders to rule out stuck rings (No smoke last time and only 15K miles on engine, so expect all 6 will be good)
2)   Re-assemble carbs with new O-rings, so not fighting leak in cracked
3)   Apply fuel to carb assembly and check for leaks
4)   Drain bowls, and then see if flow stops to verify float valves working
5)   Re-test petcock on tank verifying flow only occurs when vacuum applied and in ON or RES position
6)   Mount tank approximately 1ft above carb assembly, attach fuel line, then test flow without then with vacuum to petcock
7)   With good tests in steps 1-6, reset pilot screws to 2 turns out and all 6 throttle butterfly valves align in the closed and wide-open positions
   Remount carb assembly and fuel tank back on to bike, and then re-run fuel flow test without and then with vacuum to petcock
9)   With no gas leaks, turn petcock ON, start engine in choke for 30 seconds, then take off choke and let idle (if possible) for 2-3 minutes
10)   Stop engine, and then check oil level
11)   If oil level looks normal, then hook up vacuum gauges for carb synchronization, start bike, and then adjust screws (note – will be following Honda service manual procedures)
12)   Swap vacuum gauges with normal vacuum lines or plugs, and then using the stubby pilot screw tool, adjust the pilot screws for optimum idling
13)   Stop motor, and then re-check oil levels
14)   Hopefully with no detectable problems, it will be time for a ride with periodic roadside oil level checks.  Period of stops lengthening when no oil problem detected.  Staying close to home at first in case problems detected.

Questions:
Sparkplugs – All 6 are NGK DPR7EA9’s
Oil change frequency – Every 4,000 miles
Engine mileage question - 15,400 (recently retired, so more time to ride)
Crankcase oil overflow location – From under the bike at the rear wheel looking forward towards the crankcase, look just below the hydraulic clutch housing between the bottom 2 mounting bolts on the back of the round crankcase cover

Well I have my work cut out for me this weekend, so I’ll post to this thread if the problem gets resolved.  If not, then its back to the starting point but this time I'll keep a written journal and photos with possibly paying the local Honda mechanic for help.  Have a great weekend riding (wish I was).

[pancho]

I have no doubt you will get to the bottom of this,,, both the overfilling crankcase and the glasses of home brew, just wondering what order it will be in. It will be interesting to see what you finally come up with as the culprit.

Try to get the motor up to a uniform operating temp before performing the carb sync, otherwise everything you do will keep drastically changing with the temp. If your bike was idling OK and hadn't been messed with, it wont take much turning on any of the adjustment screws to dial in the carbs.

[Rio Wil]

Is the crankcase vent hole any where in this photo?  The four vent.drainage tubes were moved aside for claarity....

[Ricky-D]

Nope

***

[Rio Wil]

So what does this describe??

"Crankcase oil overflow location – From under the bike at the rear wheel looking forward towards the crankcase, look just below the hydraulic clutch housing between the bottom 2 mounting bolts on the back of the round crankcase cover"

[Ricky-D]

The crankcase vent is on the top of the motor and the vapors pass thru a trap and then with a hose ending up connected to the bottom of the air cleaner box.

***

[Rio Wil]

The crankcase vent is on the top of the motor and the vapors pass thru a trap and then with a hose ending up connected to the bottom of the air cleaner box.

***

Ricky....the following verbiage is from the  description of the problem.....I ask again, what is this describing??

-----------------------------------------------------------------------------------------------------------------------------------
Next day, went out and noticed oil on floor.  Troubleshooting steps to date:
--Traced it back to rear crankcase overflow hole. 
--I checked dip stick and it was over filled. 

"Crankcase oil overflow location – From under the bike at the rear wheel looking forward towards the crankcase, look just below the hydraulic clutch housing between the bottom 2 mounting bolts on the back of the round crankcase cover"

----------------------------------------------------------------------------------------------------------------------------------

[pancho]

Rio, this guy is just learning his bike and has been working under a few misconceptions.

 Does RIO stand for the backseater of a Phantom?

[98valk]

have checked the bowl vents?
from one of my posts on the subject.
http://www.valkyrieforum.com/bbs/index.php/topic,22852.0.html

this is from Rider mag sept 1988 about the '88 goldwing Gl1500.
they had the hydro-lock problem and it turned out to be the bowl vent hose was sagging. "the low spotfills with gas and prevents air circulation, much like a sink trap. without a connection to atmosphere, the float bowls pressurize and raw fuel is forced up and out of the carbs through the needle jet. From there gravity takes the fuel down the intake runners. if that cylinder has an open intake valve, hydrolock." "The article states that honda issued a Product Update kit on a fix in feb of that yr which included a metal air-vent pipe and a vacuum fuel valve."
Looking at the service manual pics in the carb section it shows the vent hoses as straight sections just laying loosely on top of other hoses. My 98's vent hoses have a 90 degree end. the end is installed into holes in the rear carb support frame.
So this might be the reason and cause of the problem for some bikes.

http://www.valkyrieforum.com/forum/vrcc_tech.cgi?noframes;read=1274246

honda service bulletin fix

http://www.goldwingworld.com/pages/sb1.pdf

[pancho]

Rio, this guy is just learning his bike and has been working under a few misconceptions.

 Does RIO stand for the backseater of a Phantom?

Unless he has a hole punched in his clutch cover,,, or the bottom mounting bolt missing from the clutch slave cylinder.

[Ricky-D]

One misconception is about a crankcase overflow hole.

There is no such thing.

***

[SC_Valkman]

Here's picture of my 1997 GL1500C crankcase oil overflow hole.  Since it has a D-shape, I'm assuming it was  intentionally cast into the case.


As for progress, I'm planning on doing the carb assembly bench test with fuel:
1)  Bowls fill, and then stop flow at peak
2)  Checking for any leaks
3)  Drain holes work, and then close off and let fill again to verify float valves close again.

Picture of rebuilt carb assembly

[salty1]

Good thread SC Valkman! Sounds like your on the home stretch. I'm still confused about the overfilling of your crankcase. Hopefully all your efforts cure that problem. 

[Ricky-D]

I think you're mistaken.

That is a relief for the slave to let any brake fluid pass that may be leaking from the piston.

***

[Chrisj CMA]

That hole in the slave cylinder area is not an over-flow for anything.  As has been stated its in case the slave for the clutch is puking oil, it will come out there.  A friend of mine that overfilled his crank case had oil blowing up into the vent but never came out that hole