DT175 1978

Haven't checked the old one with a magnet yet, but I will. Thanks again for all of your help. (and for your patience with me) I'm getting a pretty good idea of what things I need to do next, and I've got some work to do, so I better get some work done. I'll come back and post up again if I run into any specific questions, or to report back on how things worked out for me. -Thanks

Okay - another question or two. After doing some research online... now I've got even more questions... My manual (from 1983) says to take the new gasket out of the package, put grease on both side of the gasket, and torque to 18 ft/lbs The internet says: take the new gasket out of the package, anneal it, put aluminum paint or copper gasket sealer on it, torque it 18 ft/lbs, 100 miles later re-torque it. SO... do I anneal a brand new gasket? Do I grease it, paint it, what? Is there an FAQ I can refer to for this?

So, I've had trouble finding quality head gaskets on eBay... I finally broke down and called my local Yamaha dealer, who said he can order me one direct from Yamaha. It would be the Yamaha authorized direct replacement... he couldn't tell me much about who actually manufactures it, or exactly what it's made of. He said it should be the same size and materials as the original - basically, best available. I assume it would be the same one available through "yamahapartshouse.com" - that site brings up a part # 1W2-11181-00-00 which is what I think I would recieve.Link: http://www.yamahapartshouse.com/oemparts/a/yam/50041a8af8700209bc7858e1/crankcase-cylinder The only picture I could find of that part number online is on a completed eBay auction - http://www.ebay.com/itm/Genuine-Yamaha-Cylinder-Head-1-Gasket-MX175-DT175-More-1W2-11181-00-00-NEW-NOS-/321130642303?nma=true&si=EXs%2Bh65nTyRX9ZZCSwKj%2BLmVP2g%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557 The price my Yamaha dealer quoted me, while not great, is something I could live with. You guys think I'd be alright with whatever it is that my local dealer would source for me (from Yamaha)? With no help, I'd probably just order it up and run with it.... but I just want to check with you more experienced folks. Thanks.

Okay. Now that's what I want to hear! I want to, get it apart, and then take my time getting everything right. I'll follow your advice from the other thread and check out the piston and rings, decarbonize and clean up everything, and check for any other obvious issues before considering reasembling with new gaskets (and I'll look for real copper / NOS / the brand you recomended.) Sound okay? I'll report back if I run into any questions or issues along the way. Thank you for all of your help over the last few days, I really do appriciate it.

I'm very new to working on bikes and have a question on how to store my "work in progress" while I'm working on it. I'm not able to bring the bike in doors / into a shop. I usually park under a "carport". I need to remove my exhaust system, head, and cylinder on my DT175E. I expect to have enough work to do before reasembly that I have these pieces off for some period of time. It is possible that I may get stuck on something small and end up having the head off quite some time. What precautions should I take to aviod things like dust and moisture from entering the engine? In the carport I normally park under, it stays dry from rain but it is a bit of a dusty area as fine dust from the gravel driveway drifts in pretty heavily whenever a car is coming or going. I also worry about moisture from the air as I live in an area that rains often. I thought that I would just try to cover / wrap up the whole bottom end with plastic or something to cover up the piston and opening (piston in proper holding fixture per shop manual) to keep stuff out. Does that sound okay? Is there a better way? Thanks and sorry for such a 'newbie' question.

Thanks - I'll try my best to describe what it's doing. The bike does start, and it does run and ride. I cannot correctly set the idle - the idle can only be set too high, if I try to lower it, it's too low and dies - I can't find the "in between" to get a correct idle speed. I get best results adjusting the pilot air screw pretty much completely closed. When I first start the bike and it's idling in the driveway, you cannot rev rpms up high - like it's "stuck". It's better after it warms up. Then it reacts to the throttle more normally. When I attempt to test ride, the bike takes off normally at low RPM but begins to struggle and sound bad about 3000 rpms... like it's "stuck" and won't rev any higher... it slowly 'works through' that 'rough spot' and eventually does rev to higher rpms. It seems to smooth out as it gets past that "rough spot" and approcahes the shift point. I have: cleaned the petcock and screen, I'm getting good fuel flow. I emptied the fuel and replaced with new fuel - tank is very clean inside. Installed a reproduction carb, instaclled a new (oiled) air filter, and new (properly gapped) spark plug. Some of the things above seemed to make mild improvements, the old carb spewed fuel out the overflow, and the new one helped a bit but the overall running condition is pretty much the same. I sprayed WD40 at some areas hoping to identify leak points and believe I identified a leaking head gasket as described in the first post. re-torqued the head nuts, still no change. I'm reaching the end of mechanical abilities. I want to improve my mechanical abilities, but I'm hoping to get some info on what to check or do next... I'm happy to provide any info I can and I appreciate you trying to help.

By the way - I'm sorry if my posts are getting confusing. I'm trying to be clear, but maybe giving too much info? Let me know if any questions. I'm not very experienced and trying to determine what I should do next. The goal is for the bike to run well. I appreciate any guidance.

So, I went ahead and took the seat, tank, and exhaust off so that I could get to the head nuts. The nuts themselves weren't as bad as I'd feared and seemed to to fuction pretty normally. I did notice that the head nuts were 1/2" and I wondered why they weren't metric? I found that the head nuts were already torqued to at least 18 ft/lbs. Just to make sure the nuts were working I backed them off just a bit and they broke free pretty normally, then I re-torqued them to 12 ft/lbs and then 18 ft/lbs in a criss cross pattern. I put everything back together and fired it up. Nothing seemed different. Should I just try a new head gasket and then see where I'm at? Maybe I should just plan to pull the head itsself and decorbanize the head and exhaust and clean it all up and put back together with new base gsket, head gasket, and exhaust gasket then see where I'm at. Everything, including the exhaust port did look kind of dirty and bad. Not sure exactly what to do next.

Thanks again. I should be able to finally get some work done on this tomorrow. Before I jump in, I have one or two more quick questions about this. A couple of the nuts and washers on the head are pretty rusty / suspect. I’ve been soaking all of them with WD40 and hitting them with a wire brush and a toothbrush and re-soaking with WD40 to get ready for this. The suspect ones are looking better. When I go to re-torque the head nuts, should I back them off at all first, to see how easily they turn or maybe so as to start all 6 at “finger tight”? Or do I just set the torque wrench for 18 ft/lbs and tighten only? Can anybody describe the “criss-cross pattern” my manual says to use… is that like a star pattern for lug nuts on a car… I’m only confused because it’s 6 nuts. After the first nut, do I do the one directly across or go for more of a star shaped pattern? Once I have my exhaust off, if I cannot complete the head job in one day, do I need to block off the exposed exhaust port and what is the best way to do that? Sorry for all the dumb questions. I really want to get all of my ideas in order so tomorrow I can dive in hopefully makes some progress.

Thanks again. I will try torqueing them first and see how that goes. Now that you mention re-using... how about that? What does "anneal" mean? I saw ebay sellers selling old used ones. They said heat it up to glowing red hot and it's good to re-use. Is that really a thing that works? Whould I be able to do that with the one I have (assuming I can get the nuts torques to 18 ft/lb)?

Well thanks, for that. I don't want to buy poor quality - that's why I needed to ask. So, steel is not good for the head gasket. Do either of these look better? http://www.ebay.com/itm/Yamaha-DT175-IT175-MX175-Complete-Gasket-Set-New-294-/141019949983?pt=Motorcycles_Parts_Accessories&fits=Year%3A1978|Model%3ADT175&hash=item20d571ab9f&vxp=mtr [url="http://www.ebay.com/itm/Vesrah-Complete-Gasket-Kit-Fits-Yamaha-DT175-1978-1981-/330982663044?pt=Motorcycles_Parts_Accessories&fits=Year%3A1978%7CModel%3ADT175&hash=item4d101aa384&vxp=mtr I haven't spotted any "Noboru" or NOS, but I can keep looking.

Hi everybody. I haven't been here in about a year as I haven't made any progress on my project in about a year... until now. To review - becuase people probably won't remember me, I am not very experienced in working on engines, so I'm trying to learn. I am dealing with a generally poor running '78 DT175, and I FINALLY found a problem that could explain why I can't set the idle and the poor running I experience. Head Gasket. I'm pretty sure it's leaking... I spotted a clean spot along the edge of the head gasket that just looked "different", and with the bike running, I shot some WD40 at it. The engine running made the oil bubble up just like finding a tire leak with soapy water... I shut it off, and the bubbles quit, started it up and the bubbles started up... repeated a few times to be sure. I'm pretty sure I've got a leaking head gasket. SO... I'm looking at eBay for a head gasket and also an exhaust gasket as the exhasut will have to be removed to remove the head I see a lot of gasket kits that say they have everything for a "complete engine rebuild" - does that include the exhaust gasket? They don't detail exactly what's in the kit, and I think I see it in the photo, but I'm not sure... Link to what I'm looking at: http://www.ebay.com/itm/Yamaha-DT175-E-MX-1978-1979-Gasket-set-complete-New/220378204101?rt=nc&_trksid=p2047675.m1851&_trkparms=aid%3D222002%26algo%3DSIC.FIT%26ao%3D1%26asc%3D16802%26meid%3D613700581762132395%26pid%3D100005%26prg%3D7926%26rk%3D1%26rkt%3D5%26sd%3D290595689978%26 1) Does that have the exhaust gasket - is that what I'm seeing? 2) Do these gaskets look okay - I've seen a couple different reproduction styles, but these looked good to me. Anybody use them or have an opinion? Is there a better option I should be looking for? Thanks for any info or opinions - I have very little experience and just wanted to check. Also, I do have it right on the head gasket leaking... right? Thanks to any and all that respond. -Matt B.

Hey thanks again guys. I appologise, I was getting a bit dispondant. Yesterday was 'one of those days' and I was pretty overwhelmed with my project along with other parts of my life. Thanks again for the good advice. I do have plenty of sockets,open end/box wrenches, screw drivers, pliers, cresent wrenches and basic stuff - it's really just an impact driver and torque wrench that I need tro be well equipped with tools. They're probably both good ideas. And you guys are right - gaskets aren't that expensive. I need to remember that I went into this with the idea of learning how to fix things - because I'm not good at it and I want to learn - so its not supposed to be easy and I have a lot to learn. I think I need to just slow myself down and re-group myself a bit, and continue on when 'my heart is into it'. Thanks for the kind encouragement. I do want to make this thing run. I really want to go for a ride! I'll try to come back and post when I have specific questions. For now, I need to gather some more info and maybe some more tools and parts. Thanks, you guys are great.

Thanks again guys. I guess I would need an engine gasket kit before even taking the left side cover off or taking the reed valve out... I think I'd also need some tools that I don't have. I think I'm in over my head. I really screwed up and did cosmetic and street legal stuff first (brand new NOS seat cover, got the plastics looking good, repalced a broken turn signal and front stop switch) and licensed it with perminate collectors plates... I've got a good looking, fully legal bike that runs like crap. Now I'm way over budget and out of skills to get it running right.... I've wasted a bunch of money I'm never getting back and I think I better quit. If I decide to keep working on it, I'll come back and bug you guys with some more questions when I have them, but for right now... I've lost faith and I kind of just want to just push it over a cliff. I keep throwing good money after bad and I just don't believe that after I go buy a gasket kit, an impact driver, a torque wrench, crank seals, reeds... I just don't think I'll get it running. And then there's the clutch and front forks which I know both need attention that I'm not fit to give, I think the financially smart thing for me to do would be to just quit. I've lost faith. This was just a stupid pipe dream anyway, I don't have the skills to fix things and this isn't going to teach me anything... I should have taken up golf. Thanks Airhead for trying to help. You seem to know your stuff.

Where does that leave me? Still checking this mystery carburetor? Should I rebuild the original before I move on? Have a missed anything? What would you check next?