How Many Times Does Your Fuel Pump Click After The Bike Sits Overnight?

[Bob K.]

I'm trying to determine if I have a fuel leak at the carbs. I expect there to be some evaporation of fuel in the carb float bowls since there are vent tubes and the passages are open to the outside world via the air intake. My fuel pump seems to consistently click 8 to 10 times.

 

When your bike sits overnight on a typical summer day and you turn the key on, how many times does your fuel pump click to top off the float bowls before you hit the starter button?

Edited September 23, 2018 by Bob K.

[uhfradarwill]

I'm trying to determine if I have a fuel leak at the carbs. I expect there to be some evaporation of fuel in the carb float bowls since there are vent tubes and the passages are open to the outside world via the air intake. My fuel pump seems to consistently click 8 to 10 times.

 

When your bike sits overnight on a typical summer day and you turn the key on, how many times does your fuel pump click to top off the float bowls before you hit the starter button?

 

After a single night,typically zero.

After a few days, then two or three clicks.

[bongobobny]

There is one important fact you need to know about as some side information. A built-in safety feature is that the fuel pump relay has a special circuit that only allows the fuel pump to run for a few seconds and then shut off until the engine starts! The actual time may vary due to slight differences in the circuit values. That means one relay may only run for 1 1/2 seconds whereas another may run for 4 seconds, etc.

 

That being said, it is a little hard to predict just how dry a set of carbs may become overnight due to so many variables, but I also think you may have a valid "experiment" going on here. Can't give you an answer here as my 1st gen has been stored for several years now...

[YamahaLarry]

The 99 RSV I've been riding for several years typically will click maybe 1 or 2 times max after an overnight sit.

 

I have noticed on the 09 that I recently purchased, that it is more. It varies, but sometimes it will click maybe 8, 10 or 12 times. I have looked all around the carbs trying to see if there is a leak and can't find one and have never smelled gas. I have no idea how much gasoline that actually equates to that is being pumped with that number of clicks or where the fuel may be going.

[Bob K.]

A built-in safety feature is that the fuel pump relay has a special circuit that only allows the fuel pump to run for a few seconds and then shut off until the engine starts!

Yes, the fuel pump cycle count I mention finishes before the relay/circuit shuts off.

[Bob K.]

I have no idea how much gasoline that actually equates to that is being pumped with that number of clicks or where the fuel may be going.

When I tested the fuel pump with the fuel line disconnected from the pump and redirected into a bowl, 8 to 10 clicks would be somewhere between 1/4 and 3/4 cups of fuel.

[SpencerPJ]

After one night, clicks 2-3 times. After 2+ nights, maybe 4-6 times. Sometimes I have to figit to get it to click any, key off and on. Could that be the relay? Where might the relay be?

[rpep1982]

You had me guessing so I went out to see. I would say at least 10 or more for my fuel pump. I couldn't keep up.

[YamahaLarry]

After one night, clicks 2-3 times. After 2+ nights, maybe 4-6 times. Sometimes I have to figit to get it to click any, key off and on. Could that be the relay? Where might the relay be?

 

My 09 was doing that. Replaced pump this weekend. Thus far, problem solved. When it failed to click, I would get 1/4 mile or so down the road and it would starve for fuel and eventually start pumping after popping the clutch a few times while still coasting.

[YamahaLarry]

When I tested the fuel pump with the fuel line disconnected from the pump and redirected into a bowl, 8 to 10 clicks would be somewhere between 1/4 and 3/4 cups of fuel.

 

Wow. Not sure where that much fuel will go. Does not appear to be leaking or going into the engine. The oil level does not appear to have risen any since I changed it a couple weeks ago.

[Johnnycyclone]

Wow. Not sure where that much fuel will go. Does not appear to be leaking or going into the engine. The oil level does not appear to have risen any since I changed it a couple weeks ago.

 

 

Is it possible it is leaking back through the pump and into the fuel tank? Something to consider.

[Patch]

I'm trying to determine if I have a fuel leak at the carbs. I expect there to be some evaporation of fuel in the carb float bowls since there are vent tubes and the passages are open to the outside world via the air intake. My fuel pump seems to consistently click 8 to 10 times.

 

When your bike sits overnight on a typical summer day and you turn the key on, how many times does your fuel pump click to top off the float bowls before you hit the starter button?

 

Have run the Cats for many years I have a pretty good understanding of leaky carbs and over simplified fuel delivery.

 

This isn't the case with this model.

 

The bench mark for the fuel relay is 5 seconds. And yes there can be a small variance.

 

If you mix bikes then evap may not be equal. Evap is surface area and temp related: the larger the bowl the greater the surface area, the higher the temp the faster the evap in relation to surface area!

 

Are the float needles leaking? The pump has a pressure switch build in; if you needle (s) leak and you want to make a quick confirmation guess via the pump then this is what I do: cycle the key twice to fill the bowls/ (book value is 10 seconds 5x2) on the 3rd key cycle you will hear the pump slow ticking down as the bowl float needle seats/ (pressure builds) cycle one more time the pump will click 2 or 3 times before shutting off/ now wait 10 seconds (the engine is cold) cycle the key again if she clicks more than say twice your needles are leaking!

 

The bowl fuel level is set because of: air volume above, fuel volume above the jets, (keeping them fed)/ and because of riding angles. This speaks to the importance of a well balanced fuel/air proportioned bowl!

 

Regarding volume test: if you were stating that the bike chokes or stumbles at near or open throttle the we would likely suggest a volume problem, or main jet issues. Would not mean that the pump is at fault, directly, but possible. I found no volume test in this manual for these pumps but seems like a fare result.

Patch

[frankd]

For a normal summer start up, probably 5-6 clicks on the 89. If I put it in the garage hot, and then close the garage door, probably 10 or more next morning. In cooler weather, much less. If I put non-ethanol gas in it, it clicks less. If I let it cool down, turn the key on and let it pump back up, I can shut off the key and the next morning it won't click at all. I blame most of it on the ethanol fuel evaporating.

[steveriney]

Both of my 1983 models would click once or twice to prime the system after riding. If you left the bike set for a week or more i would prime the system cycling the emergency kill switch and it would take around 10 or so clicks of the fuel pump to pressurize the system. I now have a 1988 it clicks around 10 to 12 times to pressurize the fuel no matter if the bike was ridden previously in the day or set for a few weeks. Also with the 1988 it pressurizes the first time powered up and cycling the kill switch does not make the fuel pump click any additional times.

I thought there might be some changes with out the 1988 operates verses the 1983's but now after reading this I wonder if i may have a fuel pump issue where the system is draining back into the tank?

[YamahaLarry]

I would think that ethanol would evaporate at a slower rate than gasoline since it has a much higher boiling point. Granted, the amount of ethanol in gasoline is supposed to be less than 10%, but it is enough that it raises both the boiling and flash points. Given that, I do not believe that ethanol would have more clicks due to evaporation.

[Bob K.]

O.k.  Sounds like I'm not completely out of the ordinary on hot days in a hot garage.  Thanks for the inputs!

[saddlebum]

Sometimes mine clicks for several seconds sometimes barely a second and sometimes it does not click at all. It depends how long the bike sat and on the residual pressure remaining in the line between the fuel pump and the carb. I actually never give it much thought because the bike runs fine. sometimes If the bike sat a long time like all winter I will turn the key on and off a couple times to better prime the fuel system before attempting to start.

Point of interest if you remove the gas cap of your car and listen while someone else turns the ignition key on and off you will hear the same thing. So I actually take comfort in the fact that the pump clicks a few times when I turn on the key.

If the is a problem say it was clicking too much I would suspect either the fuel pump is leaking off pressure or the line connection is leaking off pressure in either case the leak off need only be so slight that you may never ever even notice any type of fuel leak even slight evaporation from the fuel bowls through the vent tubes would be enough to reduce line pressure. Keep in mind line pressure is only 2 - 3 psi so it does not take much of a pressure loss for the pump to kick in and reestablish line pressure.

Edited March 6, 2021 by saddlebum

[SpencerPJ]

During riding season, mine only clicks a few times the following day.  I feel like it holds pressure and clicks less if the fuel tank is full rather than low, maybe I'm crazy though. 

[Pasta Burner]

Well I’m glad this is normal.  I’ve been wondering if my pump was on its last leg.  I continually get 12-17 clicks always rapid at first then slows down and the last few clicks trickle in.  I don’t recall if it does this when restarting it while out on a ride or at the end of the workday but it happens all the time when pulling out of the stable.  87vr.

[Pro procrastinator]

In the spring with the carbs dry id have to cycle the pump about five times before starting but just sitting overnight i really never paid much attention to it. 5 to 10 clicks seems about average. It wouldnt take much leakage from the carbs to have a fuel smell in the garage. Seafoam in every tank helps but once needles and seats wear theres not much an additive can do.

[Pro procrastinator]

Id keep an eye on the cylinder that had the whiter plug and compare it now and then with the others you might have some diaphram issues there

[saddlebum]

On 3/6/2021 at 5:29 PM, Pasta Burner said:

Well I’m glad this is normal.  I’ve been wondering if my pump was on its last leg.  I continually get 12-17 clicks always rapid at first then slows down and the last few clicks trickle in.  I don’t recall if it does this when restarting it while out on a ride or at the end of the workday but it happens all the time when pulling out of the stable.  87vr.

sounds normal to me Keep in mind also the fuel bowls are vented at the top and evaporating fuel will escape through these vents lowering fuel bowl level, hence allowing the needle seat to start to open relieving pressure on the fuel line which signals the pump to run. As pressure builds the pump begins to struggle and slow down  eventually stopping. This is all very normal. Since fuel evaporating is one of the key factors in a normally healthy fuel system it also stands to reason that both time and temp such as sitting in a heated garage or in the sun increases the amount of fuel evaporating from the fuel bowls. The fact that the pump will build enough pressure and the bike runs quite normal would tell me there is no fault with the pump. IMHO from you description I would say you have nothing to worry about. Ride the bike and enjoy any real full system problems will come to light on its own without you try to look for any. BTW despite how it sounds, that last sentence was meant to be reassuring not chastising.

[saddlebum]

On 3/16/2021 at 8:22 AM, Pro procrastinator said:

Id keep an eye on the cylinder that had the whiter plug and compare it now and then with the others you might have some diaphram issues there

Actually the lighter one is closer to normal, indicating proper fuel mixture the sooty ones are indicating abnormally rich mixture. sticking enrichment valves commonly referred to as the choke is one possible cause that often gets overlooked when checking for carburetor causes of too rich a fuel mixture. A good indicator of this is if you almost never need to use the choke to start the bike no matter how cool it is. Other possible cause outside of the carburator are low compression due to improper valve set or ( hopefully not ) worse like bad valve seats for example.

Edited March 19, 2021 by saddlebum