Drew Lane Posted June 18, 2009 Share Posted June 18, 2009 I exhausted the search option on the forum, so I hope this isn't a repeat of something someone else has already asked. So, yesterday, I bought a 1978 DT175E in running condition for $350.00. It had been sitting in a garage and hadn't run in 6 years. After a few kicks and with the choke full on, it finally started. But, as you can imagine, it wasn't a happy camper. It had what the guy described a "pretty fresh" 2-cycle oil in the reservoir. I put clean gas in it with some Seafoam. I also dumped the pan oil and replaced it with some fresh dino oil and a little Seafoam in there, too. I also pulled the carb, disassembled it and cleaned all the pilots and jets. Soaked the disassembled assembly in parts cleaner, cleaned all of that with hot, soapy water, air blasted all the parts dry, swabbed it with rubbing alcohol (90%) then applied penetrating oil in a very light fashion. The bike starts easily now and even idles! But, it ain't coming to the party just yet. When I get the bike running, 1st and 2nd gear are as fun as a roll in they hay with a redhead. But, when you open the throttle clear up and stir the tranny, she gives you the blue smoke like crazy and the engine bogs down completely. It's obvious that it's getting way too much oil in the mixture. So, the question I have is this: Is there an adjustment on the oil mix that I can make? Is it at the carb, the oil pump or somewhere else? I really don't want to go the route of pre-mixing my fuel all the time. It's pointless, IMHO, when you have a perfectly good oil pump. Link to comment Share on other sites More sharing options...
TylerP Posted June 18, 2009 Share Posted June 18, 2009 It may have a bad right side crank seal. It runs in the motor oil and if it's bad some of the oil will get under the crank and get burned. See if it smells like motor oil at all. If it is,it's not hard to fix. Link to comment Share on other sites More sharing options...
Moderator DirtyDT Posted June 18, 2009 Moderator Share Posted June 18, 2009 I presume you have changed the 2 stroke oil? The oil pump is adjusted by shims. Check if the oil cable is sticking open on full throttle. Either stiff or the cable isnt seating right when you open her up. I would then test the bike with a premix only to see if it is still happening. Link to comment Share on other sites More sharing options...
Drew Lane Posted June 18, 2009 Author Share Posted June 18, 2009 It may have a bad right side crank seal. It runs in the motor oil and if it's bad some of the oil will get under the crank and get burned. See if it smells like motor oil at all. If it is,it's not hard to fix. It's definitely two stroke smoke. Smells and looks like a weed whacker from Maximum Overdrive on a killing spree. Link to comment Share on other sites More sharing options...
Drew Lane Posted June 18, 2009 Author Share Posted June 18, 2009 I presume you have changed the 2 stroke oil? The oil pump is adjusted by shims. Check if the oil cable is sticking open on full throttle. Either stiff or the cable isnt seating right when you open her up. I would then test the bike with a premix only to see if it is still happening. I'll try the pre-mix thing. No, I didn't change the 2 stroke oil yet. The guy said he'd just added it recently to try to start the cycle. But, what he meant by recently and what I mean by recently could be very different. I'll try the pre-mix and I'll also change out the 2 cycle. Will post what I find here. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 18, 2009 Moderator Share Posted June 18, 2009 I'll try the pre-mix thing. No, I didn't change the 2 stroke oil yet. The guy said he'd just added it recently to try to start the cycle. But, what he meant by recently and what I mean by recently could be very different. I'll try the pre-mix and I'll also change out the 2 cycle. Will post what I find here. Before you get carried away. Are you SURE its not just burning the crap out of the exhaust etc. Have you tried riding through the smokey bit. To see if it clears, instead of holding WOT bring the throttle up nice and slow as the revs go up. If she chokes back it down a little and then open up a bit more. Till you get her flat out. Got to admit it would be an easy fix if it works. My 175 always got a bit smokey as she warmed up but it cleared after a minute or two Link to comment Share on other sites More sharing options...
Drew Lane Posted June 19, 2009 Author Share Posted June 19, 2009 Before you get carried away. Are you SURE its not just burning the crap out of the exhaust etc. Have you tried riding through the smokey bit. To see if it clears, instead of holding WOT bring the throttle up nice and slow as the revs go up. If she chokes back it down a little and then open up a bit more. Till you get her flat out. Got to admit it would be an easy fix if it works. My 175 always got a bit smokey as she warmed up but it cleared after a minute or two Ok, so to this point, I've done the following: 1. New fuel, 91 octane, with a dash of Seafoam 2. New crankcase oil; NOT synthetic 3. Cleared 2-cycle tank, refilled with new 4. New NGK plug gapped to 0.64mm She's running a LOT better now, but still seems to bog out WOT, even when you creep up on it and roll the power on gradually. Also seems to have a bit of a sticky clutch. Clutch will fully engage, but it's like something just holding it then letting it go all of a sudden. So, I used some penetrating oil on the cables (clutch and throttle) to see if that will help. Any other ideas out there? Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 19, 2009 Moderator Share Posted June 19, 2009 What is this seafoam you speak of? Link to comment Share on other sites More sharing options...
Drew Lane Posted June 19, 2009 Author Share Posted June 19, 2009 What is this seafoam you speak of? Seafoam is miracle juice for mototcycles! http://www.webbikeworld.com/sea-foam/ Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 19, 2009 Moderator Share Posted June 19, 2009 Seafoam is miracle juice for mototcycles! http://www.webbikeworld.com/sea-foam/ A bit like Sanatogen for bikes then Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 19, 2009 Moderator Share Posted June 19, 2009 A bit like Sanatogen for bikes then More like a laxative if it gets it moving........ Link to comment Share on other sites More sharing options...
4Skins Posted June 20, 2009 Share Posted June 20, 2009 Before you get carried away. Are you SURE its not just burning the crap out of the exhaust etc. Have you tried riding through the smokey bit. To see if it clears, instead of holding WOT bring the throttle up nice and slow as the revs go up. If she chokes back it down a little and then open up a bit more. Till you get her flat out. Got to admit it would be an easy fix if it works. My 175 always got a bit smokey as she warmed up but it cleared after a minute or two Gotta agree with the Cynic here, take off the whole exhaust system and you'll prolly find it'd choked up with a lifetime's gunk. As soon as the pipe gets a bit of heat in it it starts burning the oil out. We used to burn them out with the oxy acetaline set and compressed air when I was in the trade. If it's got a removable baffle in the muffler, take that out too, even if you have to use brute strength and vice-grips. If you can't manage this in your own workshop, it's worth taking to a shop to get it done. Also, you never mentioned the air filter, I presume you checked that. Link to comment Share on other sites More sharing options...
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