first timer question on fuel cutoff relay wiring 97 vfr750

Sorry guys i have been distracted with a car issue lately and just got back to the bike.
I think i confirmed that the replacement relay i got is also no good. trying to see if the individual from ebay i purchased from will replace with a working one. i tryed every combination possible and could not get it to work. i get voltage from the r/y and black wires but cannot get voltage out of the relay (transistor). pump works fine with power directly to it. still would like to have the system working as designed so will need to locate a replacement. Thanks for your help.

 

You've chosen to ignore seasoned advice, imagining that stock setup is somehow best, but that's not correct. You're only making more problems for yourself.

If you don't know what "procrustian" means, look it up.

Burns heal anyway !

 

I knew what "procrustean" meant, but didn't really see how it fit this situation. Unless you were refering to the way you are trying to get him to conform to your redneck ways. I tried to look up your word, but apparently it's not a real word.




If Johnny jumped off a ..... set himself on fire, would you set yourself on fire, too?

 

Honda engineers did not put the fuel cutoff in their without reason. and I think it is a good one. riding on two wheels is dangereous enough, we can use all the safety available. to each their own i say.

 

i have have had two electrical connection failures which resulted in my fuel pump not priming. both giving the appearance of a failed relay. i beleive the previous owner was chasing those and cut out the relay then gave up.


first failure i had was the blue connection.
6th Gen - Blue Connector Ground Fix - How To. - Sixth Generation VFR's - VFR Discussion

second failure i had was the main 30 amp fuse holder.
Main Fuse Melting - Honda VFR Club

both of these will result in the fuel pump relay not getting any juice and will have you chasing your tail for weeks.
A VFRNESS will save the 30 amp fuse holder. but the holder should be cut out and be replaced with a sprung inline fuse holder of the same rating and heavier gauge wiring. (the wiring bottle necks at the connection.

i hope most of this applies to your 97 (mines an 07). there is nothing worse than electrical gremlins and these bikes are full of them...

 

vfr cutoff relay problem

ok, so I got another relay, did some additional testing.
found out that I do get a litte under 12v at the output of the relay with the pump not connected when i turn on the key. but when i attach the pump, it does not work. the output of the relay drops from 12v to 0 volts. but the voltage of the two input wires are not effected, still providing 12v each.
I also considered loose or bad connections from the blk 12v line to the relay by bypassing to the battery positive and also adding another direct ground line from the battery to the ground on the pump. no difference. seems to me that the replacement relay i got still is no good. any thoughts? I also tried monitoring the output of the relay with a 12v light bulb and the bulb does not light up and the voltage drops to 0. i am stumped.

 

Sometimes ebay = junk. It is a place where people try to sell their broken she-it. Either buy a new relay or get a known-to-be-good used one out of a salvage yard or from a reliable source that is parting a bike out. Lots of hondas and other bikes use these so hopefully you can find something that will work...

 

fuel cutoff relay continued

found a picture of the relay guts. and schematic of the internal components. thought would be helpful to include on this forum.
ImageShack® - Online Photo and Video Hosting

 

Sh!t, all this time, I just thought it was fecking magic. Now that I've seen the circuit, I have to give thanks to an engineer instead, of my favourite pagan gods.

Looks easy enough to troubleshoot, to find out which part is causing all the problems. The SCR and zener being the leading pieces of interest.

 

I need help with this too, and you guys seem to know everything there is about this topic. My bike stalled out on the freeway and sputtered to a stop after I installed a new fuel pump two months prior. I removed the rear plastic hoping to find a loose hose but didn't find much apart from a very hot pump. Naturally, I thought it was the pump and ordered another under warranty. Installed it and rode about 15 mins and it died again as if it were slowly running out of fuel. After reading your comments and testing both new pumps by running the bike and hearing the clicking noise I'm thinking it's the relay.

Is the best method to bypass the relay by bridging the black/black & blue wires and then riding for 15-20 mins to see if it dies? I don't mind this as a permanent fix as long as the bike stops dying on me.

Few things:
Fuel light turns on when I turn the ignition key.
If I let the bike sit for 20-30 mins it'll fire up again no problem for <15 mins.
Bike is a stock '94.
I bought an aftermarket pump from ebay so I'm not sure if it's pumping too much and flooding the float bowls or if that's even possible. I find it very unlikely that two pumps failed within 2 months of each other.
Last thing: the bike started acting up about a week and half prior to it dying. It took a little more throttle to not stall at a stop light after ~ 25 mins of riding, and the fuel delivery felt just a bit lean.

Thank you!

 

My first thought is loss of fuel supply. The pump is cooled by the fuel. Your pump is getting hot, which may mean that it is not getting enough fuel. Did you happen to notice if the filter was empty? You should check the supply line and petcock for problems, before you start jumping relays.

 

Thanks for the quick response.

When it broke down the first time I did notice the filter was full of fuel (I replaced it at the same time as the pump). I also disconnected the bottom line to the carbs and it had fuel in it as well.

I thought the same thing as I had to remove the stock section of hose from the petcock when i replaced the pump because it was damaged and the replacement hose did bend a bit. I opened the feed line last night and started the motor and plenty of fuel came out with the hose bent as it would be when fully connected.

There could be a chance that the aftermarket hose I fitted in there closes at speed, but the bike ran fine for two months after I installed it and seems to die right around 15 minutes consistently.

 

I just checked mine after a ride and the pump was cool to the touch. Confirming what I already thought. I still think your pump is running dry, or low for some reason. Maybe it is sucking air in from somewhere.

 

Thanks for checking.

Yeah I have to agree with you on this one. I swapped out the new hoses I made for the factory hoses and filter last night and the new pump ran for a while and was pretty loud. After about 10 minutes it was very hot and still making noise. My guess is it's the fuel filter...the one I bought from fleabay 2 months ago had a component moving around inside - not sure if this means it's good or not. Since I re-installed the the old filter I assume it's bad and perhaps caused the old stock pump to fail.

I have extra fuel hose somewhere and I'm going to install that temporarily to bypass the filter and feed the pump directly.

If that doesn't work I'm going to test the flow rate/capacity of the pump. I'll probably have to suck it up and by an OEM unit.

 

I'm not sure but can these pumps get an airlock in them and not be able to clear it, I guess it is quite possible

 

They don't need to be primed, so I wouldn't think so. I drain mine every winter and have never had a problem.

 

Spent most of yesterday installing a new OEM fuel filter and I checked to make sure fluid was coming out with the fuel on. Problem is both of the pumps I have click pretty hard until they get hot. Sometimes they click slowly then they will just go crazy and start clicking very fast. Fuel delivery is spotty which makes me think karazy was correct with fuel delivery but now I think it's a pump issue. Thoughts?

 

I noticed that you said they are after market. They could be crap.

Did you mount it in the same place as the OEM? Sometimes people try to move it and end up mounting it higher than the pump can handle. Just a thought.

 

2 pumps doing the same thing doesn't sound like faulty pumps, fuel supply to the pump is my guess, can't see mounting the pump in a different position should alter its ability to pump

 

I thought fuel delivery too but I checked that and installed a new filter. Unless it's a problem with the tank? I mounted the pump in the same spot. My old filter was completely shot and blocking fuel. I'm thinking these pumps need more fuel to run properly as the old one was clicking for a week or so before the bike stalled. There is a drop or two of fuel hanging from the petcock but it's not leaking.
I'm going to try and dig up the old fuel pump and see if I can't get it to at least pump quietly even though it spits a bit of fuel out the side.