DeTour Posted September 26, 2010 Posted September 26, 2010 I've been workin on getting my dt 175 running mint. I cleaned the carb, replaced the bowl drain gasket, petcock gasket, kreemed the tank reinstalled the oil injection lines that the p.o cut and blocked, changed the air filter, replaced the boot between filter and carb and got all new clamps, replaced the gaskets on top of the carb on either side of the thing that screws onto the carb. Before i did anything, i cleaned the carb out, bolted it on as is, and poured a little bit of gas in there. I didn't really premix it with any type of measuring, but i did add oil. It ran pretty good. Then after i got the oil injection on there working, it started idling really high like 4 grand. I figured it was an air leak so thats when i changed the boot and clamps. Still high idle. Just wondering if the oil injection could have anything to do with it. Is it possible i didn't bleed it right or it's not working at all? The fact that it ran good with out it, and now like crap is mind boggling. At first start up the idle isn't too high, but after riding it for like 3 seconds the bike is real boggy and then it started revving higher and higher. Could it just be a case of adjusting the throttle cable? Everyone keeps telling me to spray around with carb clean or something like that, but with it already idling at 4 grand i'd rather not. Any point in the right direction would be much appreciated, thanks!
Moderator Airhead Posted September 26, 2010 Moderator Posted September 26, 2010 I would try to eliminate the oil pump as the culprit. To do this just unfasten the small oil line from the carb spigot and block off the spigot with your finger, does this lower the idle? To bleed it just fill the oil tank up then remove the small screw with a gasket under it that is at the top of the oil pump. Let the oil run until any bubbles stop. There is also a 'Priming' operation to be done, when the engine is running hold the pump pulley fully open for around 30 seconds to allow maximum stroke and push the oil through faster.
DeTour Posted September 26, 2010 Author Posted September 26, 2010 Well My carb doesn't have a port for an oil line. I only have the one small line that goes into the crankcase. Here's a pic. and the routing. When i replaced the throttle cable i followed the manual on priming whereas i spun the wheel with the screw out until clear oil was coming out. Maybe i should disconnect the lines and try some premix? i Don't know....
Moderator Cynic Posted September 26, 2010 Moderator Posted September 26, 2010 You have done something to the carb, there just wouldn't be enough fuel in the system with the slide shut to allow it to run at 4000rpm for more than a very short time. Is the cable right, some have a self adjuster in them that can play silly buggers, is the slide in right. I've got it in the wrong way round before that has the revs climbing faster than a home sick angel. My money is on a carb issue, where is the idle adjuster set? Does the throttle slide seat all the way down, assume nothing you may have a cable thats a little short? Any of these are possible, just some options for you...
DeTour Posted September 26, 2010 Author Posted September 26, 2010 I have the air at 2 1/4 and the idle at 1 1/2. I did just replace the cable too. when i rode it and it ran good it was with the old cable. So i guess i'll be checking that again. Thanks for the help! It just seemed weird, but the oil injection and the cable were the only things i did after i had it running decent already, so it kind of narrows it down to those two.
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