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Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 5:32 am
by PKOS
Im trying to get my old 87 up and running, has been sitting for some years ,so refreshed some parts ,new stator ,new rectifier ,new designer clutch springs ,coils , Anyway .
The engine turns over ,the lights ,indicators work, but No power to the fuel pump ,and no spark ,beyond me what it is ,any help would be greatly appreciated ,as lost my job and need to sell it .
Thanks
KP
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 5:43 am
by Designer
Well first,...Glad To Hear From You again!
Sad to hear that you lost your job though.
I would look first to see if the fuses are not blown,...if they do look okay, the might not be. If you have a Meter check them for continuity.
If not, take the Fuse for the Lights ( which we know works) and place it on other Circuits. See what you get.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 6:14 am
by hillsy
Sounds like you may have done something with wiring seeing as you've replaced a bunch of stuff. You should probably re-check what you've changed first up. I assume it was running when parked?
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 6:45 am
by Lechy
Try jumpering the wires at the clutch lever and sidestand switches, a paperclip works well for this.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 9:07 am
by Herb
Since it is turning over, but no spark, I would start by finding out about the power and signals to the coils. The fuel pump will not get power until the rear cylinder has a spark signal.
I hope that it isn't the ignition box being bad because you cannot buy them anymore.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 10:31 am
by Lechy
Not a common occurrence but it happened to me. After removing and re-fitting the stator cover to fit a new shifter seal I had a no spark situation, it took me quite a while to trace it to 2 partially broken pulse cables at the transit block on the cover. Another time was that I hadn't fully engaged the locking tang on the plastic connector going to the CDI allowing it to separate.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 5:14 pm
by PKOS
Thankyou for the replies and help ,Designer [hi mate]ive checked the fuses several times and was okay ,Hilsy ,it was running when parked, but missing on the front cylinder ,i mindlessly threw the old rectifier away, so i cant check it against the new one ,[one thing i have to learn, just because a part is new doesnt mean it works ] like new fuel pump off sleezybay, which doesnt work, tested the old one seperately and it still works ,but Not when connected to its wire on bike .
Will pull the stator cover off and check it and the kick stand and clutch ,i also found New ''Igniters'' for sale ,not suzuki [Regulator Rectifier .com, and CARMO ,and not cheap either [ ,and rippoff secondhand ones on Sleebay].
will let you all know what transpires
cheers
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 5:47 pm
by hillsy
PKOS wrote: ↑Mon May 16, 2022 5:14 pm
Thankyou for the replies and help ,Designer [hi mate]ive checked the fuses several times and was okay ,Hilsy ,it was running when parked, but missing on the front cylinder ,i mindlessly threw the old rectifier away, so i cant check it against the new one ,[one thing i have to learn, just because a part is new doesnt mean it works ] like new fuel pump off sleezybay, which doesnt work, tested the old one seperately and it still works ,but Not when connected to its wire on bike .
Will pull the stator cover off and check it and the kick stand and clutch ,i also found New ''Igniters'' for sale ,not suzuki [Regulator Rectifier .com, and CARMO ,and not cheap either [ ,and rippoff secondhand ones on Sleebay].
will let you all know what transpires
cheers
Before you pull the cover you should check both pick-up coils are wired correctly / sending a signal. If you put a voltmeter across the 2 wires you should see min 2.4V when you crank the motor. Also check the resistance across the two wires - should be between 170-250 ohms. Each wire to ground should be open.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 16, 2022 9:52 pm
by Herb
I had an issue with my 87. I had the seat off, it was running good before I took it off. Put it back together and it started great, but when I sat on the seat it quit. I fooled with it for a couple of hours and finally discovered the ground wire to the ignitor was broke inside the insulation right at the pin in the plug. Every time I would sit down the pressure on the wires was enoug to separate the connection.
I found the problem by checking continuity on each of the wires to the ignitor.
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 10:38 pm
by FinTruder
I bring my question in this thread also. I got following symptoms with my bike. It starts fine with full choke. After warm up it idles good with no choke. When i turn throttle to max it takes rpm,s but stalls when i let go. Same happens while driving. Low rpms fine but with full throttle it stalls almost immediately. I got new stator, regulator, full cleaned and rebuild carbs, synced with dyno, new fuel hoses, new fuel, new battery, new spark plugs and no loose ends with wiring. Can bad fuel pump cause these problems. It is original pump and bike is -90. It runned fine in dyno and test runs few weeks ago but now it aint.
Thanks.
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 11:16 pm
by Herb
FinTruder wrote: ↑Sun May 22, 2022 10:38 pm
I bring my question in this thread also. I got following symptoms with my bike. It starts fine with full choke. After warm up it idles good with no choke. When i turn throttle to max it takes rpm,s but stalls when i let go. Same happens while driving. Low rpms fine but with full throttle it stalls almost immediately. I got new stator, regulator, full cleaned and rebuild carbs, synced with dyno, new fuel hoses, new fuel, new battery, new spark plugs and no loose ends with wiring. Can bad fuel pump cause these problems. It is original pump and bike is -90. It runned fine in dyno and test runs few weeks ago but now it aint.
Thanks.
Gotta think about this one...
Does it die or do the rpms stagnate while driving?
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 11:23 pm
by hillsy
FinTruder wrote: ↑Sun May 22, 2022 10:38 pm
I bring my question in this thread also. I got following symptoms with my bike. It starts fine with full choke. After warm up it idles good with no choke. When i turn throttle to max it takes rpm,s but stalls when i let go. Same happens while driving. Low rpms fine but with full throttle it stalls almost immediately. I got new stator, regulator, full cleaned and rebuild carbs, synced with dyno, new fuel hoses, new fuel, new battery, new spark plugs and no loose ends with wiring. Can bad fuel pump cause these problems. It is original pump and bike is -90. It runned fine in dyno and test runs few weeks ago but now it aint.
Thanks.
I know you said you changed the stator and RR but is it actually charging properly? If it is not then the spark can break down at high RPM / under load.
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 11:26 pm
by FinTruder
Herb wrote: ↑Sun May 22, 2022 11:16 pm
Gotta think about this one...
Does it die or do the rpms stagnate while driving?
Rpm,s goes good until shifting 3-4 gear put some throttle and while decreasing the throttle it gives few pops from pipe and dies. Same with idle, full throttle and cutoff, it sounds like bike is suffocating from throttle.
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 11:28 pm
by FinTruder
hillsy wrote: ↑Sun May 22, 2022 11:23 pm
I know you said you changed the stator and RR but is it actually charging properly? If it is not then the spark can break down at high RPM / under load.
It is charging fine, no power loss whatsoever
Re: Starting ,spark/fuel pump problem
Posted: Sun May 22, 2022 11:53 pm
by FinTruder
I'm thinking that fuel pump may have dirty contacts/spikes. Correct me if I'm wrong, pump hits harder when i give some juice for motor, right? If pumps contact surface is blocked it won't give enough fuel and engine stalls? Im my experience these old pumps worn off little by little, not immediately except if it goes broke.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 23, 2022 2:06 am
by hillsy
FinTruder wrote: ↑Sun May 22, 2022 11:53 pm
Correct me if I'm wrong, pump hits harder when i give some juice for motor, right?
Sort of.
The pump is triggered by (low) pressure. Not really related to the throttle however this will start the pump up quicker.
Have you bypassed the fuel pump relay? A common gremlin in the Intruders.
Re: Starting ,spark/fuel pump problem
Posted: Mon May 23, 2022 2:15 am
by FinTruder
hillsy wrote: ↑Mon May 23, 2022 2:06 am
FinTruder wrote: ↑Sun May 22, 2022 11:53 pm
Correct me if I'm wrong, pump hits harder when i give some juice for motor, right?
Sort of.
The pump is triggered by (low) pressure. Not really related to the throttle however this will start the pump up quicker.
Have you bypassed the fuel pump relay? A common gremlin in the Intruders.
I need to check that out. I know i didn't, but can't say if some previous owner did. If the pump is not capable to pump fuel quicker, it gives me these symptoms right? If pumps contacts can run bike just enough to keep it running at low rpms but not give enough spark to contacts to run it harder?
Re: Starting ,spark/fuel pump problem
Posted: Mon May 23, 2022 2:27 am
by hillsy
FinTruder wrote: ↑Mon May 23, 2022 2:15 am
I need to check that out. I know i didn't, but can't say if some previous owner did. If the pump is not capable to pump fuel quicker, it gives me these symptoms right? If pumps contacts can run bike just enough to keep it running at low rpms but not give enough spark to contacts to run it harder?
The pump doesn't change speed - it just runs for longer when the carbs need more fuel.
There is a volume test in the manual for the pump - I'm not sure of the volume but its something like a pint a minute?
Re: Starting ,spark/fuel pump problem
Posted: Mon May 23, 2022 3:15 am
by FinTruder
hillsy wrote: ↑Mon May 23, 2022 2:27 am
The pump doesn't change speed - it just runs for longer when the carbs need more fuel.
There is a volume test in the manual for the pump - I'm not sure of the volume but its something like a pint a minute?
Hmph.. pump relay is there and working.. could it be...
I start to think my mufflers.. i got pretty much 14y old supertrapp mufflers with discs and closed cap.. Looks pretty.. um.. carbonish
Could it be that simple.. i start to remove those discs and caps
Re: Starting ,spark/fuel pump problem
Posted: Mon May 23, 2022 7:06 am
by FinTruder
Mystery solved. I took supertrapp discs off and drove 100km,s in highway 140kmph no problems anymore. Badly clogged exhaust and discs full of carbon waste. +10y of uncleaned pipes makes intruder unhappy xD