You can't find where it pops out at the other end? It MIGHT be a compression release, but man I can't recall them having one..
Does it get spark?? :mellow: I hadn't even considered that.. :laugh:
Have ya shot a teaspoon of gas right down the spark plug hole and kicked it over as hard as ya can and yelled at it?? :angry: That helps sometimes.
Does it get spark?? :mellow: I hadn't even considered that.. :laugh:
Have ya shot a teaspoon of gas right down the spark plug hole and kicked it over as hard as ya can and yelled at it?? :angry: That helps sometimes.
If I make it to ricks sometime and remember, I will look.. He has a parts bike that is already opened up and half missing...
It should pretty self explanatory if ya look it all over.. Should be a spot for the cable to mount, then I wanna say on those, there's a little arm on the injector that pulls up to open the flow up...
It should pretty self explanatory if ya look it all over.. Should be a spot for the cable to mount, then I wanna say on those, there's a little arm on the injector that pulls up to open the flow up...
Hey everyone! So....I've had some time to work on this bike with little luck. The cable in question was in fact the Throttle/Oil Pump cable that I replaced with a new one. Fuel and oil tanks were drained, cleaned and new oil and fuel put in. Changed the trans oil too. Cleaned the carb. Removed the oil pump and blew out the old oil and primed in new oil, however, putting a cordless drill to the oil pump didn't seem to pump any oil so I'm not sure if it's faulty and if there's a way to rebuild it. Replaced the spark plug and new plug connector. Also, blew out and cleaned the exhaust. Lastly, adjusted timing gap and cleaned the ignition coil contacts. I know I have good compression, fuel and spark.
So here's the result. It started and ran for about 15 seconds...got it to run for about 30 secs then it just dies. Wait a few minutes and it starts and dies again. I can't figure out what's goin on. When it does start for that short amount of time, I'm at half to full throttle as it won't run at idle. Carb idle was adjusted to 1.5 turns out as the manual states (yes, I have the manual believe it or not). Anyone have any ideas as to what's goin on? Any help would be great as I'm debating on whether or not to spend any more time on this thing.
So here's the result. It started and ran for about 15 seconds...got it to run for about 30 secs then it just dies. Wait a few minutes and it starts and dies again. I can't figure out what's goin on. When it does start for that short amount of time, I'm at half to full throttle as it won't run at idle. Carb idle was adjusted to 1.5 turns out as the manual states (yes, I have the manual believe it or not). Anyone have any ideas as to what's goin on? Any help would be great as I'm debating on whether or not to spend any more time on this thing.
That's classic symptoms of overheating on a Suzuki 2 stroke of that vintage, and it shuts down after a short time. The oil pumps go bad, don't pump enough oil, and there you go.
Try an experiment: MIX the gas and oil at 20:1 in the gas tank. Yeah, that's heavy, but most of them were that mix back then. See if the problem goes away, or at least gets a lot better. Then you can decide what you want to do. I removed the oil pump on mine and stayed with mixed gas. Mine was an old Suzuki FZ-50 moped with the same engine.
Try an experiment: MIX the gas and oil at 20:1 in the gas tank. Yeah, that's heavy, but most of them were that mix back then. See if the problem goes away, or at least gets a lot better. Then you can decide what you want to do. I removed the oil pump on mine and stayed with mixed gas. Mine was an old Suzuki FZ-50 moped with the same engine.
2-strokes are about as easy as it gets to diagnose.
I highly-doubt the engine would overheat without oil after running 15 seconds but until you are certain the oil pump is working correctly, it's always a good idea to pre-mix your fuel for the initial debug.
Your engine has spark. That means the focus should be on the carburetor.
Since you disassembled it and cleaned it out and then it ran where it didn't before, that definitely points towards the carb being the culprit.
What it sounds like to me is that first you need to make sure your carb is set-up correctly. Make sure the fuel level in the bowl is correct and all the jets and bleeds are clean. Then make sure no rust or debris inside the gas tank getting to it. Usually the gas tanks from older bikes have rust in them. If yours does, that might explain why it will only run for a few seconds. If the rust gets into the needle and seat, it can impede or totally block fuel flow to the bowl.
Try taking your carb apart again and look inside the float bowl to see if there is a bunch of crap in there. Then clean it and remove the needle and seat and clean them out good too. Then reassemble the carb and try again. You may want to use another container as a gas tank to prove it out if your gas tank is rusty. You can also try using a small fuel filter to catch the debris before it makes it to the carb.
This is the typical problem I usually face when I get another KV75. They almost always need to have the carb thoroughly cleaned and the gas tanks de-rusted and sealed. After that, they usually start on the first kick and run like champs.
I highly-doubt the engine would overheat without oil after running 15 seconds but until you are certain the oil pump is working correctly, it's always a good idea to pre-mix your fuel for the initial debug.
Your engine has spark. That means the focus should be on the carburetor.
Since you disassembled it and cleaned it out and then it ran where it didn't before, that definitely points towards the carb being the culprit.
What it sounds like to me is that first you need to make sure your carb is set-up correctly. Make sure the fuel level in the bowl is correct and all the jets and bleeds are clean. Then make sure no rust or debris inside the gas tank getting to it. Usually the gas tanks from older bikes have rust in them. If yours does, that might explain why it will only run for a few seconds. If the rust gets into the needle and seat, it can impede or totally block fuel flow to the bowl.
Try taking your carb apart again and look inside the float bowl to see if there is a bunch of crap in there. Then clean it and remove the needle and seat and clean them out good too. Then reassemble the carb and try again. You may want to use another container as a gas tank to prove it out if your gas tank is rusty. You can also try using a small fuel filter to catch the debris before it makes it to the carb.
This is the typical problem I usually face when I get another KV75. They almost always need to have the carb thoroughly cleaned and the gas tanks de-rusted and sealed. After that, they usually start on the first kick and run like champs.
so how's the mt50 now?
was the 15 second run time diagnosed?
are you running straight gas and relying on the oil pump or premixing?
i have a 71 that had a broken oil pump cable and the prev. own replaced only the throttle end.
might run premix and leave the oil in the tank and hopefully it will still lube the bottom end both ways.
other issues with mine are the ignition switch. was missing the key and frozen so gonna improvise and rig a 4pdt on/on toggle for off and night settings.
the petcock. its missing the o rings and haven't figured out fabbing some o rings or seals or using 2 in line on/off petcocks for the tank breather and fuel.
have a pdf of the repair manual but wish there was one out there for the owners book.
oldmt50: used to live in southfield, if i was there to help would be fun!
was the 15 second run time diagnosed?
are you running straight gas and relying on the oil pump or premixing?
i have a 71 that had a broken oil pump cable and the prev. own replaced only the throttle end.
might run premix and leave the oil in the tank and hopefully it will still lube the bottom end both ways.
other issues with mine are the ignition switch. was missing the key and frozen so gonna improvise and rig a 4pdt on/on toggle for off and night settings.
the petcock. its missing the o rings and haven't figured out fabbing some o rings or seals or using 2 in line on/off petcocks for the tank breather and fuel.
have a pdf of the repair manual but wish there was one out there for the owners book.
oldmt50: used to live in southfield, if i was there to help would be fun!
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