Mech

The fuel and the ignition could both have power to them and then be controlled by the ECU earthing them. Wires almost never break inside the loom. They break at/where they go into the terminals where they connect to things, or they wear through and short where they rub on the frame. If there is a break in a wire, it's going to be inside that wire's insulation and you probably won't find it by looking. You need a multimeter that can check ohms and use it to check the continuity of the wires from one end to the other. You really don't want to be going pulling the loom apart just for a look. I'd inspect the loom for shorts to earth, (which will be obvious by the worn through tape and insulation) and check for continuity from one end of each wire to the other. You need to bear in mind that the power to the coil could come straight from a fuse, then be earthed inside the ECU and controlled by the ECU to fire the spark. Or it could have the same setup except with the power coming from in the ECU. Or the coil might have an earth wire(or not, it might earth internally) and be sent a short pulse of power from the ECU to make it spark. If it's the last option then there will only be a short burst of power in the coil's circuit when the motor is turning over. You really need to know or figure out which system it is so you know which wire is meant to have power, and when it's meant to have power. If you tell me where you got the manual from I'll try and download it and see if I can figure it out with you.. And do you have a list of the possible trouble codes? Is there one for the coil ?

The fuel circuit might have power all the time and then the ECU earths it when they want the pump or injectors to go.. If it's fuel injected. That's fairly common. The manual should describe how things operate.. Do you have a manual ? And what sort of motor does this have ? Suzuki by any chance ?

Ok, so in the list of trouble codes, is there one for an open circuit in the ignition feed wire ? Perhaps there is no code for that fault.. If there is a code for that fault, then I'd still be expecting a bad earth or power to the ecu.. They often have several power and earths to a ECU. And all the powers and earths going into the ECU are for separate circuits, so you need to confirm they are all good. It's also possible that the ECU acts as a CDI and only sends a pulse of power to the coil when a spark is needed. I'm not familiar with those machines. Other than that.. there's a break or an earth in the wire from the ECU to the coil.

On cars when there's no trouble codes they recommend checking all the power feeds and earths, especially to the ECU.

Ha.. If you work on it you'll probably void the warranty.. Blocked exhaust ? After it's died take the sparkplug out and see if it's wet or dry..

Oh ok, and Hi. And I guess being as how you're fixing a quad you must be rural ? Being a country mechanic's a good thing, plenty of variety and great customers..

That's a strange one ! What sort of chain adjuster does it have, a manual adjustment or an automatic one ? Is it in good order ? If it's an automatic sort, is the ratchet in good condition.. Does it do it when it's running or as you rotate the motor by hand ? Is it perhaps trying to jump when the motor either backfires or as it comes up against compression as the motor's coming to a stop ? Some cam chain tensioners don't like the engine being turned backwards, or backfiring. The tensioners are only designed to take the slack out of the chain on the loose side, and don't always handle the load of being on the tight side if the motor's being turned backwards or backfiring. Are the sprockets in good condition ? Does the top and bottom sprocket look to be in line if viewed from above.. could the chain be trying to creep sideways and come off the sprocket ? Is the chain the right pitch for the sprockets ? Do the links sit nicely on every tooth they contact ? Are the cam bearings good ?

Start it up from cold and listen as it idles, then listen with a very gentle rev within a minute of startup, and then slip it into gear and apply a little load while it's still very cold and listen. Then warm it up for a few minutes but not long enough for the oil to get hot, and do all three tests again. Then warm it right up so the whole thing and the oil's hot and do all three tests. Take notes of all three temps three tests and report back.

There are ways to pinpoint the cause of the noise, but it still takes a bit of experience to say how bad it is.. So.. does the noise seem louder hot or cold ? If it's loader cold how long before the noise quietens slightly.. Pistons expand a lot in the first minute as they heat up. If it's worse cold and quietens quickly then piston slap would be the suspect. Bottom ends don't quieten much in that short time but they do get loader as the oils warms and thins.. in ten minutes say. If you put it into gear and apply a bit of throttle to load things up, does the sound get louder or quieter.. Piston slap and broken rings and valve problems won't get much quieter or louder, but crank play will get louder under a load. If it's in neutral and you give the throttle a very little blip to raise the revs a couple of hundred revs, then let it off again.. what does the sound do. Is their a momentary taping sound ? That's a sign of the piston pin being worn. Piston pin wear doesn't get noisy under load but it does as the load comes off the piston and the piston can fly up and down freely with a few revs on. Temperature making a difference to the sound tells us a lot. Load effecting the sound tells us a lot. Revs with no load on things(just as it reaches revs and then starts to slow) tells us a lot. The combination of these three things helps us pinpoint the problem.

It's important that metal head gaskets can get their heat away into the block and head.. so using any sort of sealant isn't a good idea. The head and block need to be clean metal too.. if there's dirt/carbon between the parts then the heat can't get away to the head/block. It's a good idea to have a bit of ten mill thick plate glass in the workshop to use with wet and dry sandpaper to clean and/or flatten heads.

Manuals say use a special threaded pressing tool. I made a tool from a steel plate that fits in the center of the rim underneath, with a threaded shaft through it, then on top with the threaded rod going through it I have a bit of 4X2 with two 2X1 bits of wood about 4 inches long at each end under that, and then 4 and a half inch long steel strap plates bolted through the 2X1 and the 4X2 at their outer ends. I leave the bolts loose so the steel strap dangles down so I can start them under the rim's lip, then as I tighten the center threaded bolt the 4X2 presses on the 2X1s which press on the outer ends of the steel straps, which jam in between the rim and tyre and press down right up against the rim.. The 2X1 allows the plates to press the tyre down by one inch which is normally enough to get things started moving with a bit of soap and some hitting with a bead breaker.. I made it ages ago and it's saved me heaps of sweat and swearing..

I would be surprised if it was possible to graft the 500 into a 300 gearbox. If the parts did fit, the gearbox and drive line might not stand the strain anyway. You could look up an online parts catalogue and see if the cases or gears are used in both models. Some catalogues online let you choose a part, and then click a button to see what other models the part fits.. And yeah Suzukis are not really high performance, their great advantage is their low low ratio. They are great for farm work and really hilly country. If you want sporty performance though.. get a honda.. haha.

The centrifugal clutch is used to drive the bike from a standstill, and locks up a bit above idle revs, and the plate clutch is controlled by the gear change lever to prevent gears getting crashed when you change gears with a few revs on. The plate clutch has an adjustment on the right hand side of the motor near the oil filter. The adjuster is under a bung. Get a manual and have a read on how to adjust that. It's very likely the plate clutch adjustment is your problem,(adjusting it is routine maintenance), and an easy job so the first thing to check.

Yup.. there's no gasket under the cover, just sealer. I doubt that's where the leak is coming from. The valve adjusting caps or the decompression lever's shaft seal do leak quite often though. First thing to do though is to identify where the leak's coming from. Clean the top end with a bit of petrol and a hose off, then run the engine while you sit and watch, or go for a short run and check for leaks before it's had a chance to spread oil all around again. The valve cover's are real easy to change, and the decompression lever and shaft pull straight out together once you've removed one bolt going down through the cam cover. The bolt is the one near the outer end of the shaft. Take note of where the spring goes, and it's a bit of a struggle to get it back into place as you refit the shaft, but it can be done with some pliers on the spring to wind it into tension as you push the shaft in the last ten mills or so.

Hi. The threads are standard anti-clockwise to remove. Have you tried using a six sided socket.. rather than the more common twelve spline socket ? A common mechanics trick for rounded nuts is to use a cold chisel on two of the flats of the nut, on opposite sides of the nut (if you can get at them). The idea being to partially split the nut in line with the stud it's on. In most cases once you've put a groove down both opposite flats of the nut, you've both enlarged the nuts diameter enough for a socket to get a bit better grip, and at the same time spread the nut so it's looser on the threads. Even if you cant get straight at the side of the nut with the chisel, putting a groove from the outer edge down as far as possible will likely allow the socket to get a better grip. Six sided socket should be the first thing to try though...

View File 1999-2004 Suzuki LT-F300/300F King Quad Service Manual 1999-2004 Suzuki LT-F300/300F King Quad 300 Service Manual Submitter Mech Submitted 12/28/2021 Category Suzuki ATV  

That plate's probably on a tapered or splined shaft. I'd wind that six mill bolt out a small amount, perhaps six turns, then either use a puller and pull the plate or lever it up, and give the bolt a sharp tap with a small hammer. Don't bash it too hard or you'll bend the bolt. It's not likely to damage the threads if it is a long bolt as you say.. Allen keys are tough. If you are using a puller, press against the allen key and then tap the end of the puller's bolt.. If it's a splined shaft the plate should move with the puller, but if it's a tapered shaft it will need a tap, either on the end of the allen key, or on the side of the sleeve under that plate.. A sharp tap with a small engineers hammer's better than a hard whack with a bigger hammer.

You need to use a volt meter to look for voltage across places, and at times, where there shouldn't be any.. So from one side of the solenoid to the other should show battery voltage when you aren't trying to crank it over, but that voltage should drop to near zero when you operate the starter. If it shows more than about a half volt as it's cranking then there's a dirty connection in there somewhere, possibly inside the solenoid or in one of the battery lead terminals. Then check for voltage across(from one end to the other) of each battery lead while cranking, there should be no voltage shown.. if there is a voltage shown it's because there's a dirty connector or near broken lead. To speed things up you could check for voltage while cranking right from the battery to the starter terminal, if there's no voltage shown then those leads and connections are clean and tight and working. If there is more than about a half volt then there's a bad connection in that power feed somewhere so you start checking one lead and the solenoid at a time to find which one. Then do the same process with the earth.. from the battery earth terminal to the starter body should show no voltage while cranking. If there is a voltage then there's a bad earth connection somewhere, so check one lead to earth, then earth to engine, then engine to starter body. When checking the starter leads, make sure you are checking from terminal to terminal, they can get bad connections where they crimp to the wires..

Yeah could be a leaking float needle valve, or the float level might be set too high, or there might be a leak between the float needle valve's brass housing/seat and the carby body. Take the carby apart and pull the float out, then the needle and then the needle's seat. Check the "O" ring or washer that seals between the seat and carby body, then put that in and check the needle's clean and put that in, then fit the float and check it's height adjustment.

Ok. I've been keeping a look out for you... I'll keep watching. To go with the press you will need a couple of short lengths of what I think you guys call girder steel.. it's cross section is like a capital I... That's a capital "eye", not an "L". It needs to be big stuff, like six inches tall and about four across the two side plates. That's to support the crank on the bed of the press. You also want a bit of angle iron about two inches by two inches. That doesn't need to be very long, about eight inches will be plenty. It's what you use to align the crank webs as you start pressing it together. You set the webs in the angle so they line up initially before you press the second web on. The books often say to use a special tool that's a bit of rod that goes through holes in the webs, but the angle does fine as long as you get it all sitting nice. You're also going to need those centers I was talking about.. Have you figured anything for that yet ? Before you press the old crank apart, take note how far the crank pin pokes through the webs. Mostly they are about flush with the web face but sometimes they poke out a little. It would be a good idea too, to make sure the new parts are identical to the old, in the length of the pin in particular. If the new pin's a bit longer or shorter then you'd allow for that when you press the new pin in. The rods sometimes seem a little different in dimensions or weight if they aren't genuine but that's ok.. As long as they are the same length anyway. .haha Being a little thicker or chunker is ok. I'll look for your posts.

Sounds like you need to fix the earth wire or connection, and it may not come out of gear because the gears in the diff are wound up and can't let the engaging dog slide till you back up a little.. that's quite common on a lot of things.

Simple things first.. You could try a new spark plug.. that black/rich could be caused by it misfiring. Misfiring could also be caused by some other electrical problem as has been said but those things need diagnosing and are dearer to fix.. The idle mixture only effects idling and a tiny amount of throttle, after that other jets take over. You should check the air-cleaner, and also, those things have an auto fuel cutoff tap which plays up sometimes and lets the sump fill with petrol.. check the oil level.. If it's too full, or if fuel seems to be disappearing out of the tank, check the fuel tap mechanism. Do a standard tune, plug, aircleaner, valve clearance, then start to diagnose it. If you have a timing light it's an easy test to drive with it connected and watch to see if the spark starts disappearing as the faltering starts

Yeah, that isn't a good look for a new piston alright.. Good onya finding it.