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Discussion Starter #1
Hey everyone hope your day is going well. I am new to working on my 954 and could really use the members expertise. I took a chance and bought a bike that was partially disassembled. Based on that I have never seen it running. I have put everything together and added new spark plugs and a new battery. When I turn the key on I can hear the fuel pump initialize. When I turn it over and turn the throttle I get a mist of gas. I have checked the spark at all four Spark Plugs and they are working (albeit Cyl 4 seemed to be a little weaker. I have checked the Bank Sensor and it is working. I checked the wrapped yellow plug near the headlights and there is no burn marks. I have a Power Commander III which I disconnected and got the same result. The tank was completely empty and clean. I put in new gas. I have not checked compression, but it sounds like it is good (I know that means nothing.

Does anyone have any suggestions or insight? Thank you!
 

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Sounds like a fuel pump issue.
spray starting fluid into the throttle bodies after you
take the airbox off and tell me if it fires,
If it fires on starting fliud, you likley have a fuel pump issue, clean it and or rebuild it.
if it wont fire on starting fluid, you likely have a safety lock out issue like clutch switch, side-stand switch, but being that the pu,p is priming,
id be looking at the fuel pump
let the pump run into a jar it should be getting like 12 ounces per a certain amount of time or some thing like that its in the manual'
Then check the voltage at the stick coil while cranking and get back to me bro
 

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Hey everyone hope your day is going well. I am new to working on my 954 and could really use the members expertise. I took a chance and bought a bike that was partially disassembled. Based on that I have never seen it running. I have put everything together and added new spark plugs and a new battery. When I turn the key on I can hear the fuel pump initialize. When I turn it over and turn the throttle I get a mist of gas. I have checked the spark at all four Spark Plugs and they are working (albeit Cyl 4 seemed to be a little weaker. I have checked the Bank Sensor and it is working. I checked the wrapped yellow plug near the headlights and there is no burn marks. I have a Power Commander III which I disconnected and got the same result. The tank was completely empty and clean. I put in new gas. I have not checked compression, but it sounds like it is good (I know that means nothing.

Does anyone have any suggestions or insight? Thank you!
Can you post a quick video of the “mist” you spoke of?

That would kinda tell me your getting gas to the throttle bodies, but why no ignition? Hmmmmmm

I would probably check compression before I got any deeper. You will want to see at least 170 psi across all 4, and no more than a 10% drop between any cylinder.
 

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Discussion Starter #4
I tried spraying starter fluid in the throttle bodies and it did not start. The mist of gas is coming from the crankcase air breather hose that connects to the bottom of the air housing. That makes me think I'm getting gas and since it isn't igniting it is coming back to the air housing. I tested for spark already, so I need to check compression next. It seems so close to starting sometimes but just doesn't> Might take me a couple days to do the compression. Thank you both for your help so far.
 

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Hi are you in USA or somewhere else:wink
Edit; is your Headlight fuse OK, was thinking it could be the Cam Pulse Sensor but that would set up a fault code
 

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cam sensor does not always through a code, but if you've a spark and fuel the cam and crank sensors must be singling the ECU or it would be sparking and fueling. It could be too little fuel (fuel pressure regulator failed); often these leak gas in to the engine so if there is gas in the engine oil that could be a reason.

When you put the key on the pump primes, but does it run when you crank the engine over? It should do.

unless the compression was bad on all four i would expect one of more cylinders to at least try and fire, cough or splutter, but worth ruling this out all the same.

Are all the vacuum hoses connected on the inlet manifold and fpr? lots of air leaking in could stop it running. Make sure you do not kink the fuel line when putting the tank on too or the pump will prime but would be unable to push fuel in to the fuel rail/injectors.
 

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If you are spraying starter fluid and it’s not starting your spark it probably not as strong as you think it is or like was mentioned your battery is not putting out 12+ volts. Start with testing the battery voltage because it’s the easiest. Then check all your electrical connections (I don’t just mean look at them, you should unplug them and then plug
Them back in to make sure they are firmly in place. As also previously mentioned take extra care to not pinch the fuel line when you remount the tank. If you do all of these things you will be well on your way to eliminating all the free ways to solve your problem. All too often people start throwing money at it before they test these easy things. I don’t know all the grounding points off the top of my head but make sure all your ground straps are secure. If anything is not grounding properly it will cause a ton of problems.
 

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Discussion Starter #9 (Edited)
Update. I have a new compression tester coming tomorrow as my old one is not reliable and my friend is on vacation for a week. Someone asked if I am in the USA. My feeling is I am getting fuel, but the spark though present seemed a little weak or I possibly have bad compression. I measured the voltage at the ignition coil connection to ground and with key on showed 13.2V. When I crank the engine over I am actually seeing it go down a little instead of up to 100V. I am using a standard voltmeter not one with a peak voltage adapter as stated in the manual. Is this why I am not seeing it bump up to 100V or should a standard voltmeter work? The ignition coils Ohm ranged from 1.4 to 1.5.

If this is the issue I will start troubleshooting further down this path. No matter what I will take Mace's suggestion to clean the fuel pump. I will also have compression numbers tomorrow night. Thank you all again for taking the time to help me on this!
 

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I just reread your post again just to rethink it and if you are getting a mist through your positive crankcase ventilation and or exhaust gas recirculation when the bike isn’t even running that would make me think you are blowing by the piston rings way too much. Definitely do a compression test if you have the ability. I’ve actually never messed with the pcv or egr on my bike but I’m assuming it has both. After doing a little research it seams as though on our bikes it is referred to as a pair valve and acts mostly like a pcv valve and there is no exhaust gas recirculation?
 

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The easiest way to check if you have fuel is to crank it a few times and smell your tailpipe. If it smells like pure gasoline you are probably getting fuel. Do it before and after to get a good comparison
 

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And if you want to get the party started stick a grill igniter in there, if it shoots 5ft flame out the pipe you are definitely probably getting fuel
 

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Did you personally check the cam timing and make sure all the marks are where they belong? Once you test the compression if it’s coming back consistently bad in all cylinders make sure the cams are lined up correctly
 

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Hey everyone hope your day is going well. I am new to working on my 954 and could really use the members expertise. I took a chance and bought a bike that was partially disassembled. Based on that I have never seen it running. I have put everything together and added new spark plugs and a new battery. When I turn the key on I can hear the fuel pump initialize. When I turn it over and turn the throttle I get a mist of gas. I have checked the spark at all four Spark Plugs and they are working (albeit Cyl 4 seemed to be a little weaker. I have checked the Bank Sensor and it is working. I checked the wrapped yellow plug near the headlights and there is no burn marks. I have a Power Commander III which I disconnected and got the same result. The tank was completely empty and clean. I put in new gas. I have not checked compression, but it sounds like it is good (I know that means nothing.

Does anyone have any suggestions or insight? Thank you!
Make sure the fuel line does not have a kink in it. it happen to me once i helped my buddy with his 954, fuel line had a slight kink in it and it was enough to lot let it start.
 

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Discussion Starter #16
Okay thank you all for the great information. I answered my own question on needing the Peak Voltage Adapter and it will be here on Thursday. I agree I need to go back to the basics and methodically check compression, spark, fuel flow, and connections. I will also double check the battery levels. I will update with readings as I get them. Thank you!
 

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The mist of gas is coming from the crankcase air breather hose that connects to the bottom of the air housing. That makes me think I'm getting gas and since it isn't igniting it is coming back to the air housing.

Just to confirm, the mist is coming out of the airbox rather than out of the crankcase? If so then this points to a possible valve timing problem, or badly leaking inlet valves.
 

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Discussion Starter #18
Just to confirm, the mist is coming out of the airbox rather than out of the crankcase? If so then this points to a possible valve timing problem, or badly leaking inlet valves.
Sorry I probably have some of my terminology mixed up as this is the first time working on the bike. I attached a picture from The Pair Valve modification so I can point out the hose that has what seems to be fuel mist coming back into the airbox. Note this bike does have the Driven Plates on it.
 

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Discussion Starter #20
Did you personally check the cam timing and make sure all the marks are where they belong? Once you test the compression if it’s coming back consistently bad in all cylinders make sure the cams are lined up correctly
Update: The good news is the battery is strong under load. The bad news is the compression is 87 to 90 in every cylinder. (doesn't make a difference, but it was obviously on a cold engine) Considering all cylinders are the same amount of bad I am hoping you are right and it is a cam timing issue. I am guessing there is no easy/quick way to check this without taking off the valve cover?
 
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