Strange problem on 400 scram? Help!
#1
I asked this question once before but left out the info in the second paragraph, so I got more specifics on everything I did and hopes this helps someone help me in return. I just rebuilt the top end on my scram. Started on the second pull and idles great. It even revs when you give it throttle in nuetral. Here's the problem....after I put it in forward and give it any gas it boggs bad. It will however accelerate ok if I keep the over-ride buttom depressed and it doesn't matter if you have it in 4wheel drive or not when depressed (didn't try to go very fast with button depressed, just fast enough to load it in my truck). It seems to back up fine though. I already took the carb apart twice myself and cleaned it out thoroughly and made sure the jets were A-OK as did a friend of mine also. Could this be caused by hooking up the wrong wire in the wrong place on the lighting pod( this is the only wiring I touched in the rebuild)? I know that I have the reverse and nuertal indicators connected correctly although the reverse indicator seems to be burnt out. Woud a burnt out reverse indicator possibly be the cause due to the way it is wired(I know that sounds like a stupid question, but I had to ask anyway)? I also put in all new fuel lines and cleaned out the clogged fuel selector so that it has full flow through it now. I also put in a new fuel filter and checked to make sure that I had flow through it. I already checked the air screw and it's still at 1 1/5 turnes out. I checked for leaks with spray, but didn't notice any extra rpm's when doing so. Well that's about all that I did so far. Any ideas? Anything would be greatfully appreciated.
I did raise the clip on the needle jet one notch and upped the main jet from a 270 to a 280. Could this carb change alone cause the bike to bogg as it is doing? I did have someone check out the over-ride and he said that it is operating fine otherwise it wouldn't accelerate faster in reverse. Please help? A guess is great too!
Thanks again!
I did raise the clip on the needle jet one notch and upped the main jet from a 270 to a 280. Could this carb change alone cause the bike to bogg as it is doing? I did have someone check out the over-ride and he said that it is operating fine otherwise it wouldn't accelerate faster in reverse. Please help? A guess is great too!
Thanks again!
#2
The 1st time I ever rebuilt the top end on my Scrambler I had symptoms just like you described. It turned out to be a wire that was plugged back into the wrong connector in the pod. Seems like I remember it was a brown or brown striped wire.
Seems like it had something to do with the reverse light, like when we put it in forward gear the quad thought it was in reverse so it was running like it was in reverse does without the override being pushed.
My son just happened to notice when I put it in forward gear the reverse indicator light came on up on the dash. That's how we finally figured what it was. Once we corrected the connections we were in business.
Are you sure the reverse indicator is burnt out or is a crossed wire making it think it's in forward gear instead of reverse. That may not be your problem but it sure sounds like the same thing I experienced. What are the odds two guys would make the same dumb mistake but hey, great minds think alike.
Seems like it had something to do with the reverse light, like when we put it in forward gear the quad thought it was in reverse so it was running like it was in reverse does without the override being pushed.
My son just happened to notice when I put it in forward gear the reverse indicator light came on up on the dash. That's how we finally figured what it was. Once we corrected the connections we were in business.
Are you sure the reverse indicator is burnt out or is a crossed wire making it think it's in forward gear instead of reverse. That may not be your problem but it sure sounds like the same thing I experienced. What are the odds two guys would make the same dumb mistake but hey, great minds think alike.
#3
I'm gonna find out tomorrow when I check the wires again. I didn't really notice whether or not the reverse indicator came on while I had it in forward, but I'll check the wiring on the lighting pod again and chnge a few wires around and see what happens. Thanks for the input! If you think of anything else, just post again no matter how crazy it may sound.
#4
The needle clip CAN make a change like that, that doesn't mean that is the problem, but if it is too rich in the midrange, it will run like crap. I would just drop the clip back down a notch and see if it clears up any, but if you are having to push the button for it to operate correctly, then it is surely a wiring problem.
#5
Thanks againg guys for the help. I'm gonna get right on it tomorrow morning. I'm gonna put the clip back where it was and change the main jet back to a 270 as I had it before, not that I think the main jet is part of the problem, but I'll have it back as it was before I tore it down. I'm also gonna check all the connections on the light pod to make sure all the connections are clean. And maybe as a last resort, switch a couple of wires around on the light pod to see if that helps if the jetting doesn't help. I let you know how it turns out and as I said before, thanks again and have a great weekend of riding. If you think of anything thing else I might try, let me know.
#6
One more thing to check. The over ride does connect to the reverse light via a purple wire, it could happen if the light is burnt out. But.. I would check out that wire real good and make sure it is hooked up correctly. You also have a wire, green I think, going to the lo beam headlight from the over ride button and another wire gray&white going to the AWD switch and the Trans switch. Good luck.
#7
Thanks NC. I did double check it and it is hooked up right. Even cleaned the connections. I'm gonna try and locate a new reverse indicator lamp tomorrow after I get off work, thereby eliminating just one more possiblity so to speak. then I'm gonna put everything back on the carb as it was before I rebuilt the top end and see if that doen't do the trick. I do believe though that it is an electrical problem and I hope you are right. Thanks again for the help!
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#9
Well I finally got it running right I think. I couldn't take it out for a long test ride, but it seemed to accelerate pretty good in my yard(I didn't have to use the over-ride switch to get it to go foward. I checked underneath the hood again and pooled the lighting pod off, cleaned every connection on it with emery type sandpaper. I also found a pretty filthy double connection (yellow/red and yellow wires)that go to the regulator that I also cleaned out. Changed everything back the way I had on the carb prior to tearing down the top end. Now the reverse light works again. That alone saved me $22.00. So now all I have to do is put the bumper back on that I just had fixed and break her in again with some new plugs. Qiuck question....since you are suppposed to premix the oil and gas in addition to the oil injection when breaking it in again, do you use the standard recommended plug for break in or do you go with something else? By the way, thanks for all the help. It was very much appreciated.
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