Jd101506

My major problem was working on two different quads, which were damn near identical in the first place. Confusing D7EA and D8EA plugs, near identical filters, near identical carbs… I have no problem admitting I was wrong or that I was the big dummy here. Definitely learned a lot, got two free fourwheelers up and running for under 800$ all in, and got me active on here so I’ll consider it a win. like I said above I really appreciate everyone’s patience. It definitely tried mine… 😆

Measure twice post on the forums once? 🙃

WELL. I think I solved it. So first off, I had my neighbor test my fuel as hes a mechanic, he has some kind of chromotograph and measured a sample of my oil. A VERY slight amount of fuel, but again this quad has something like 3.6quarts so its quite a lot. Couldn't sleep for a time last night so I started pawing through the manual. I realized two things. First, I installed my air intake filter incorrectly. When I got the quad, the airbox was PACKED full of mouse nest, this also means the original foam filter was toast, melted, eaten, completely gone. So when I went to reinstall, I didn't realize that I could take apart the air intake plastic shroud. I looked at it briefly and it LOOKED like it was a rivet in one side holding the plastic shroud to the guide for the mount in the box. So the ONLY way this could have been mounted was reversing the filter and installing it backwards... Which would NORMALLY be fine, but the foam filters I bought had quite a lot of glue on one end and I wonder if it was blocking the air flow or causing erratic running. Either way, I corrected this and it seems quite a bit better. Second, I think you guys hit the nail on the head. When I originally ordered the email carbs I ordered the correct PNs for each the LT300E and the LT4WD. Now they are the SAME slide style carb, but as @Gwbarm noted the jets are different. The LT300E takes a 13200-41B31 and the LT4WD takes a 13200-19B02. Again, I ordered these carbs from the SAME seller, on the SAME day, and they arrived on the SAME day to my house.... You can see where this is going. When I got it in, I had the fuel pump ready to go for the LT300 but not the LT4WD, so I left that one in the box. Installed the LT300 carb and boom! Went like it should and it was great. I DID notice on occasion, that when coming off a hard throttle I'd have a little bit of a RPM drop and every once in awhile it would stall. I didn't think too much of it since I haven't really put a lot of effort into that quad, and figured I needed a new plug and all that. So later, when the replacement fuel pump for the LT4WD arrived, I installed that and had all the following issues... So after ALL these issues and everything else... I figured I must have screwed up somewhere. So today, I parked them both next to each other and setup two VERY obviously different stations and I removed the carbs from BOTH Suzukis. I pulled the LT300e, and took a look at the pilot and the main. The 300e had a 98 main installed and a pilot listed with a 41. Thought this was weird because it was basically down the middle of the CV and slide carbs for the LT4wd... When I pulled the carb that was ON the LT4WD, it had a 112.5 main and a 20 pilot. I slapped my forehead and realized my mistake. What I DID do after, is I swapped the carbs, put the correct 112.5 and 20 on the LT300e, it fired RIGHT up and runs around the yard with no hesitation and ZERO issues. It sounds great! Because the main and pilot are SLIGHTLY off the book... I took the Shindy carb kit jets OUT of the original carb and installed in the ebay carb. Adjusted my slide/throttle and my mixture to factory. (Did this on both). Reinstalled, and MAN, it fired RIGHT up and idles like brand new. I'm attaching a video as a final proof. I double checked the overflow, and I double checked the inside of the carb after riding around for awhile and both were dry! I think I am reaching the end of my issues... Only thing now I noticed is that my speedo doesn't work so I'll have to figure that out. I have a lot of cleaning and other things to do but I am REALLY happy with how it runs! Thank you guys SO much for all your help with my issues during this! I really appreciate your guidance and patience.

Oh and while I was messing around I did a compression test just to be sure I wasn’t having bigger issues. Seems like 165 throttle open. So that’s positive!

Good info! The one that came off the Quadrunner is a VM24, so when I ordered the replacement carbs I used the Suzuki parts website and ordered 13200-19B02. Same deal for the Kipa carb. Is there a slick test I can do on the oil to see if there’s fuel in it? I’m second guessing myself that it has fuel in it. I tried the cardboard test and didn’t noticing any rings forming. The smell isn’t bad enough for me to immediately say I’ve got a big problem but that thing takes a ton of oil compared to my LT300 so it could have a bit in it and I dunno if I’d know.

No idea if this helps or hurts my case but I pulled a small bottle pump out and put some pressure on the carb. I would imagine this pumps more pressure into the carb than that fuel pump possibly could. It seems to hold pressure. I realized as I was removing this carb that the drain for the carb was kinked. So I would imagine if this TRIED to drain it wouldn’t have. The rubber hose was folded over on itself and wouldn’t let any fuel past. It’s encouraging that when I put that pressure on it, it came out in a steady stream and then abruptly ended. Tells me the seat and needle are doing something relatively right. I took a piece of vinyl hose and tried to blow through it. I know I can probably only put maybe 2psi to it blowing myself but nothing came out. I’m trying to figure out how I can make a 5psi pressure system to test the float and needle. thoughts?

I have the original carb for the LT4WD. All of these LT4WD models from 85-98 have fuel pumps. They have to, there is no way to gravity feed any fuel to them. I also removed an original Mikuni carb from this LT4WD when I started working on it because it was seized. I know for 100% fact this Suzuki has and needs a fuel pump. I also know for 100% fact that I have the right jets and needles in this carb because I matched the new Shindy ones to the ones that came out of the Mikuni from this bike that wasn’t salvageable. im using Suzuki parts warehouse to buy said parts. The part number for the eBay carb, Amazon carb both pulled from my bike, my year page that was mentioned in screenshots above. I’ll add my vin in here so you can double check I’m not horsing you around. For what it’s worth my LT300 is running great with an eBay carb and a Kipa fuel pump. I don’t know if it was a lightening strike or what, but both machines have and require the same style of carb (Slide style, NOT CV) and both use a variation of the same fuel pump. Im not trying to be an idiot here, I just can’t get this thing to not overfuel itself no matter what I do. I just got bored and pulled the slide out of the Mikuni and man, there’s fuel just sitting in the top there. Wild. Added a photo. Side note; what’s a sure fire way to test for fuel in oil? I’m second guessing if I smell fuel in it or if I’m just smelling the overflow from earlier.

I’m using the needle and seat that came with the shindy kit for the LT4WD. I’ve never used anything but the proper needle and seat which is why I’m confused as to what you are asking.

Super, thanks. I'll take a look at the vent and see what I can see. And yep, I have the slide carb in the middle diagram. The shindy kit I had replaced the jets with exactly the ones you mentioned. 100 and the 22.5. @Mech Ok, just wanted to check and make sure I wasn't missing something. So to confirm: At this point you would adjust the tang on the float needle to be more aggressive to prevent the flooding?

I guess at this point I'm just not sure how to do it. Four different carbs and they all seem to do the same thing. I guess tomorrow I will pull the OEM carb and check the floats again. The tang on the float, I assume I bend it TOWARDS the needle to increase the amount of pressure on the needle? It just seems impossible to me that all four carbs would have the same symptoms but from a technical standpoint it does make sense that the needle isn't doing it. I MAY swap my eBay carb back in because I can adjust the tang and test it outside the ATV using the vacuum from the other one. And the ebay one and the OEM one seem to function identically. One question: The needle itself on the slide of the carb. Would any adjustment to that needle help me? I noticed that the KIPA carb would run at high RPM and my throttle cable was tighter using that than the ebay or OEM... I assume that needle ONLY impacts RPM and not the mixture/how much fuel is going into the engine?

Did you happen to see the video I posted? Any idea about why the fuel would be coming out of that breather? Mech is right. The crankcase may be part of the issue but it doesn’t explain the fuel. Unless the crankcase is causing extreme vacuum somewhere? Anyone have any idea where the crankcase breather is on these LT4WD?

ok so a new data point! I messed with the carbs a bit today. I tried using the carb that I had on it previous and tried to pump fuel into it to flood it. I couldn’t get it to flood! No matter which way I turn it or anything it will not flood. I tested this by taking the old carb, pre filling it with a little bit of fuel, and cranking the engine over with the plug wire off. It pumps fuel like it should, and I can’t make it flood. Now here’s where it’s getting interesting. I noticing my oil level was a little high so I went ahead and I pulled some oil out. After I said screw it let’s try and ride it around a little. Now I left the air box cover off and I left the breather tube for the carb off. it ran around great. Like, how it should. I was astonished! that’s when I realized I forgot to put the oil cap back on. I panicked. Stopped the quad and ran back inside and grabbed it, screwed it back in and started it back up… Wellnit ran great again for about a minute… Now it is doing the same thing as before and the carb has fuel burping back out of the breather! im attaching a video. it got me thinking though… where is the crankcase breather on these? Maybe mine is plugged and as it generates heat and runs it slowly pressurized and pulls fuel hard from the carb and dies? Is there a way to test this? I noticed one breather is missing the little snorkels they come with. and @Gwbarm the carb that is currently on here is from a LT300e that I have. It’s a known ‘good’ carb but I installed the Shink rebuild kit with proper jets for the LT4WD. So far it’s functioning the same as the eBay carb, which I tested on the LT300 and that works fine. IMG_7733.mov

When I run it with the fuel pump it struggles pretty bad, runs a little rough and definitely will stall over time. Without the fuel pump you can see how it runs so I’m near positive it’s just pushing too much fuel and flooding the carb. I’m going to adjust the float fairly aggressively and see if that might help. Right now it’s within spec, but I wonder if I need to just go a little more aggressive.

More data! Definitely running way too rich. Fuel in the crankcase I think, the oil level is higher than I remember it being and smells a little bit like fuel… But the big clue is the plug, pictured below. Black as night. I took a video of the fuel pump off the carb. The quad runs really well in this way, so I think Mech you are right that something isn’t seating. QUESTION; does that fuel pump look like it’s pumping correctly? From descriptions I’ve seen it seems fine but I want to be sure. (I’m adding a YouTube link for the video because it’s larger than the attachment limit) vidoe here: It’s amazing to me this could be traveling across 4 different carbs.. but here we are! Is there anything else I can check on this? I took the bowl off the two carbs previously and both floats were .97 and .98. Unless I’m measuring wrong, the spec is .9 to 1.0in. I would assume thisnis ‘fine’ but I could adjust it more aggressively.

So your suggestion is to change float needles or adjust the float? It just seems impossible that over four different Quadrunner 250 carbs I would have all four not be able to hold fuel pressure. Doesn’t it? Hell even the rebuilt OEM carb isn’t. I haven’t been able to locate a clear instruction on how to adjust the float on these carbs as yet. I debated trying to restrict the fuel pump somehow to test but I haven’t figured that was a worthwhile test long term.

Installed the OEM pump, and I have the same issue. It will run around the yard at RPM with random stumbles but will slowly die at idle. It will smoke a bit as well as I let it sit and idle. The mixture screw seems to make very little difference on the carb. So I installed the KIPA new carb from Amazon. When I first put it in, it just wants to run at an extreme rpm, all the time. I couldn’t slow it with the idle adjustment and the slide needle (thisnis a slide carb not a CV) didn’t seem to make much difference. While I was bored I rebuilt the old LT300 carb and swapped the jets from the LT4WD into that carb with all new seals. I installed that carb and it did the SAME thing where it ran really fast rpm. Couldn’t figure it out. As I was standing there… it suddenly dropped rpm and then went back to the same old behavior it used to have where it would idle and then slowly kinda die and run like junk. So now I’m back to square one. I’d like to think the fuel pump is good and it just seems like it’s letting too much fuel in. At this point I’m going to pinch off the pump and mainline fuel into the carb again to see if it still runs ok. If it does… it feels like a float issue… across three different carbs. But I don’t have much else at this point to go on.

Hi all! So I’ve got a early model (86? Maybe?) (slide carb)Suzuki Quadrunner I’m working on. I’ve having a series of really wild fuel problems and I’m hoping someone could point me in the right direction. So when I first got it the fuel pump and carb were both toast. Rusted, awful, unrebuildable messes. So I bought a pair of cheap Chinese ones of eBay and worked on the rest of it. Carb arrives first. I install it, hook a battery up, mainline some fuel into the carb and it runs. Sounds great actually. Ok, cool, runs good, I’m fine. Wait a few days and the fuel pump shows up. Install and the quad runs like absolute dog crap. It would hesitate, stumble, stall, the works. It does sit and idle and start up quickly though. So I assume it’s the fuel pump, so I end up saying screw it and I buy an OEM one. 85$. Meantime I can still get it to run well with drip feeding it fuel. New pump comes in and installed. Same thing. It stumbles, acts like it’s dying, may stall, etc. This new pump is an OEM Suzuki so my assumption is it’s fine? I ended up swapping the carb wondering if the float or something is actually my problem. This is a different carb, a WELL REVIEWED Kipa carb from Amazon. I install that and I have a whole different set of problems… this carb will run at mid to high RPM, idle adjustment screw be damned. All the way in or all the way out it runs at the same RPM. I ended up taking the main slide and needle out and I swapped it for a different one and the RPM dropped. Not a lot but a little. So I try and drop the carb needle as low as I can and it’s still funky. Something isn’t right. So after swapping that carb again I end up rebuilding the Mikuni carb from my Suzuki lt300, and swap the jets over from the Quadrunner rebuild kit I had ordered. Put that carb in and it does the same stupid high idle. I take the choke cable off the bike entirely and it makes no difference and the throttle cable has plenty of slack. As I’m standing there staring at it, it just suddenly drops the idle and sits there idling pretty happy… so I climb on, and it has the same annoying jerky, slow throttle response that the first eBay carb had. So to recap: 1x Kipa fuel pump kept pushing way too much fuel in. 1x OEM Suzuki fuel pump made the carb from eBay smoke like crazy and idle adjustment did absolutely nothing. I could go a full 2 turns from the stock setting of 1-3/4 turns out in either direction and get the same awful running 1x ebay carb worked well on a mainline of fuel right to the carb gravity fed. But runs like dogshit around the yard. Jerky and low idle and smoking on both the Kipa carbs and the OEM carb. 1x Kipa carb runs at super high RPM and won’t settle down no matter what I do with the cables or anything else. 1x rebuilt mikuni did the same as the Kipa but then randomly dropped rpm to idle and then started running like the ebay carb. So I’m appealing to the brains here. I find it hard to believe I’ve tried this many carbs and such and I haven’t found a working solution. As an aside, I’ve swapped the plug, done an oil change, and done a general inspection. Compression test I haven’t done, and I haven’t adjusted the valves but it starts easily. And runs easily mainlining fuel. Sitting in the garage it sounds fine. I’m attaching a video of it running with the eBay carb and the OEM fuel pump. It’s just really weird. It feels like I’m flooding it because when it’s idling I can smell it and there is a little smoke from the tailpipe. Ill add more video tomorrow of it running like crap around the yard. IMG_7396.mov

New data point! I had ordered a second Kipa fuel pump from Amazon (A refund/replacement for the broken one, the ball from the ball valve inside the inlet was loose inside the pump) arrived today. The so now I have three of these things at the house. I installed this new pump on the LT300e… and magically, it runs perfect. Like, this thing hasn’t run this well yet. I took it for a spin around the yard, no stalling no stutter, nothing. It runs like an absolute top. I left it running in my driveway for a bit and it ran for about 2-3 mins untouched and popped right into gear and sped away when I jumped back on it. So… the old Kipa, the ‘working’ one that I swapped from the 300 to the LT4WD, might be my issue. Works well enough to pump fuel, but doesn’t work well enough to maintain. This was the one that was in the 300 and it ran like crapola, then on the Quadrunner and it ran like crapola. I’ll wait until I get the new OEM fuel pump here and installed on the 4WD before I make any final decisions but so far it seems like this may have been my issue or at least partially. while I was spending money I ordered a ‘name brand’ carb from Amazon (easy returns) to see what the needle clip and default settings are. Reviews were very positive about it being a plug and play so I’ll likely swap it and see what happens.

SOLVED. I got the new key switch in today. Managed to get the front light off (the mounting bracket was rusted in place so I had to break it a little), and the pull the trim around the keyswitch. when I started tracing the wire to unplug it I grabbed ahold of the boot that covers all the wiring… when I did that I pulled back slightly and the keyswitch wiring was revealed, I found that the bullet connector for the ground was stuck in the sleeve but was NOT plugged into the female end. So I seated it stiffly, put the battery on, fired it up and sure enough… It now turns on and off as it should! I swear I checked that 3-4 times before ordering a new switch… Anyway, I can mark this one as solved! Thank you guys SO much for all your help in this thread. For any future Suzuki ATV folks the separate black/yellow bullet connector off the keyswitch is a nightmare!

As a side note; mine are both slide carbs. I double checked. The needle jet is set in the 4th postion, aka ‘rich’ condition. Would I be running rich like this if the needle was set that low? I’ll probably pull the OEM needle out and see what that was set to and try to match it. It’s just still weird to me they both seem to run well when the pump isn’t running… is there any adjustment to these mechanical pumps? thanks!

Update: The carb is DEFINITELY wayyyy too full of fuel. I pulled the carb out of the LT4WD and there is literal fuel pooled in the intake boot. At this point: Is it possible for the pump to pump TOO much fuel into the bowl? Is it just the needle that stops the fuel from getting pumped in? Would adjusting the float prevent that? I pulled the float, and I'm confused about the float adjustment in the screen shot. The needle has a TINY spring in the back side of it, where should the tang be resting on the needle to measure from the bowl to the float? Or should the tang not be pushing on anything on the needle? I realized that I have the same exact carb on both, so it stands to reason BOTH are set the same way, ie, too rich. If I measure from JUST at the point where the tang touches the needle while seated, i get a .87in measurement. In the manual it states .92 to 1.00in. Is that my issue?

Hi all! I've got a 1988 LT4WD that I am working on. It sat for almost two decades in a shed, so I replaced both the carb and the fuel pump (Pump was rusty, carb was ok, but had a pin hole in the bowl itself?). Now, I went el cheapo and I replaced BOTH with Chinese aftermarket Carb and Fuel pump. Now is where it gets confusing: So I did this SAME thing on my other Quad, a 1988 LT300E. They take the same PN carb, and a similar fuel pump, (One has a 90 degree bend in the vacuum port). I've been battling the four wheeler a bit with some electrical issues, but I noticed that at idle it runs GREAT when I gravity feed fuel from a burp can into the fuel bowl of the carb... But as soon as I put it on the fuel pump from the tank, it idles EXTREMELY low and smokes a little. To me, this indicated that the carb itself was running rich. I adjusted it a little on the LT300e, but I could never seem to get it right, it still will slowly die at idle when warm, but ironically if I CHOKE the motor, it'll start up and run. I dont know if this is because the RPM increases? But the quad will run around the yard great at RPM and then die at idle. Now, the LT4WD. I ended up with a faulty fuel pump for my second (I think the spring isn't seated inside as I can hear one rattling around) so when I installed it it WOULD NOT pump fuel. So I ended up swapping the LT300 pump onto the LT4WD. Boom, pumps fuel. I put it all back together and got my tires on. I ran it around my yard and it exhibits the SAME symptoms as the LT300e! It will run around at RPM, but it will not stay running at idle, it drops realllllly low RPM and will start smoking a little as if its running rich. Again, when I ran it with the fuel pump OFF I didn't have this issue. In my head I'm thinking it would be a mixture screw OR float issue... But the mixture screw doesn't seem to help me on either, and the bowls are not over flowing (I checked both overflow lines). Is there something I'm missing here thats obvious? Is there a vacuum line or something I missed? Maybe some configuration or something I missed? I reviewed the manual and nothing stood out to me. Conclusion: Two different Suzuki fourwheelers, two different carbs (Both are chinese Ebay carbs) that BOTH run well when I mainline fuel from a drip can INTO the bowls, BOTH do not keep idle and seem to run extremely rich as they run great at RPM but slowly die at idle. Adjustment screws, idle screws be damned. I ended up ordering a new Suzuki OEM fuel pump for ~90$ just to have it and see if it makes a difference. Any advice here though would be SUPER appreciated!

So that’s part of the problem, that service manual doesn’t exist here for the LT300e. I have the one for Quadrunner, but not the 300E. Before I take it all apart I’ll plug it into the harness and see if the new switch fixes it. If it does, I’ll be tearing that light off somehow I guess.

Ok, so its been awhile BUT I have a new keyswitch coming today to test. I'm going to start there, the key is kinda sh** anyway, so this is a good opportunity to test a few things. ... But I can't figure out how to remove the headlight. I can see the bolts holding the ignition plastics on UNDER the light, but is there a slick way these Suzuki headlights pop off? I don't want to break it removing. Since last message I QD contact cleaned ALL the contacts between components and to the frame. I also got a brand new carb, fuel pump, and replaced the fuel lines. The quad runs signficantly better, but even after messing around a bit it still runs a little weird and seems to want to stall on occasion still. Its making me lean more towards the electrical being off somewhere. I swapped this carb and fuel pump into my 1988 Quadrunner 4x4 and it runs great, so I know the carb and pump are good.

So right now. The key won’t turn the fourwheeler ‘off’ when the engine is running. It starts fine, and I don’t notice any other weirdness aside from a really low idle and the the key switch not turning it off. I can turn the engine off with the engine kill switch though. And you mean the two small wires off the backside of the solenoid? Never tested this before. Is there a way I could rule out the switch? I ordered a replacement new carb for it so I can ‘rule out’ the seals in the carb. At the very least it’ll isolate it to a vacuum problem or electrical for the low idle. Where are all the grounds on these? I found one on the middle of the frame bolted in, but I didn’t see any others obvious. Was thinking I could clean all the grounds just to start. I’m seeing ignition switches are really inexpensive. I just sort of expected that if it was the ignition I would have issues more than the engine turning off. Like, right now my headlight and tail light turn on and off as expected flipping between the third position and second. I left the battery connected overnight and didn’t have any drop in voltage so I know there isn’t a phantom draw anywhere either. Thank you!!