1991 XR250R Smoking after Rebuild
- Thread starter XR400RMan
- Start date
If you have a 3 piece oil ring, and if the wavy portion gets overlapped during assembly, (easy to do) then you will have copious amounts of oil smoke and even oil coming out the exhaust.
Please don't ask me how I know this.:o I will say it was late at night and the excitment of the first race of the season played a part. I did miss practice while I pulled the top end down in the pits.:eek: But I was young then.
Please don't ask me how I know this.:o I will say it was late at night and the excitment of the first race of the season played a part. I did miss practice while I pulled the top end down in the pits.:eek: But I was young then.
- Thread starter
- #28
Ok I am back with some more information, The guy at the shop that rebuilt my engine set the valves lose because he said they would tighten up but since the first time I have started the bike you can hear the valves moving and I think he adjusted the valves to lose and not quite tight enough, Also when I went an looked at the bike there was black oil residue on the bottom of the rear fender and my dad and me saw this so when I was riding it in the guys yard my dad looked very close but could not see any smoke and then he rode it and I didn't see any smoke, When I had the Top-End rebuilt the guy said he didn't put any oil on the rings when he put them on the piston but then he put synthetic oil in the bike,I thought you weren't suppose to use synthetic oil in a new engine, Could this have messed something up? My dad is taking the bike back next week hopefully because I am tired of it smoking, I have to check the oil level every couple of hours when riding and add some, I have already just about runined my Jersey because of it and I am afraid I will ruin my whole Top-End again if I don't hurry up and get it fixed, I am using 20W-50 oil right now, Thanks Matt
DualSportr
Member
- Aug 22, 2000
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It is tough to break in an engine on synthetic - it'll glaze the cylinder. Which is probably what has happened.
Whatever the case, it needs to be fixed - even if the reason for the smoking isn't that big of a deal, running this engine low on oil every time you ride definitely will cause problems in the long run.
Whatever the case, it needs to be fixed - even if the reason for the smoking isn't that big of a deal, running this engine low on oil every time you ride definitely will cause problems in the long run.
- Thread starter
- #30
Dualsportr I don't run the engine LOW ON OIL WHEN I RIDE, I top it off before I ride each day and then in about 2 hours of riding I will check it again and add if neccesary, Me and my dad are taking it back to the shop this next week to see whats wrong, I forgot who mentioned those 3 oil rings and said that oil can accutaly come out of the exhaust, Well I looked on the back of my jersey the other day and there was oil spots all over it like say when I was stopped and the wind was blowing the smoke to the front of the bike and I was on the bike then it blew oil on my jersey,My new jersey looks pretty bad now, Matt
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DualSportr
Member
- Aug 22, 2000
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Just take the thing in and get it fixed. Jeesh!
- Thread starter
- #32
Dualsportr there is no need to get an attitude, You didn't read my other reply right,Because I said that I filled it up with oil and then you came back and said RUNNING THE ENGINE LOW ON OIL WILL RUIN THE ENGINE IN THE LONG RUN,I know it will and thats WHY I FILL THE DARN THING UP AND KEEP A CHECK ON IT, Thanks for your help Dualsportr and everyone else's, I will try and get another update when the shop takes the engine apart, Matt
DualSportr
Member
- Aug 22, 2000
- 527
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My point was that if you check the oil, fill it, then ride 2 hours - then check the oil again and need to add some at that point, the engine is running low(er) on oil at some point during the ride.
Also, the ring blowby (or whatever is pumping oil out the exhaust valves and into your pipe) is causing other problems that we have all talked about here.
The reason I finally got sick of this discussion is that we have all given you the reason for the problem (and the possible fixes), but it's been OVER TWO MONTHS and you've not done anything to fix it, just continued to voice the same issues over and over.
All I'm saying is, it's been since Jan 17th - get the danged thing fixed and quit'cher bichen!
Also, the ring blowby (or whatever is pumping oil out the exhaust valves and into your pipe) is causing other problems that we have all talked about here.
The reason I finally got sick of this discussion is that we have all given you the reason for the problem (and the possible fixes), but it's been OVER TWO MONTHS and you've not done anything to fix it, just continued to voice the same issues over and over.
All I'm saying is, it's been since Jan 17th - get the danged thing fixed and quit'cher bichen!
- Thread starter
- #34
Dualsportr I am sorry if I annoyed you in anyway, I am just trying to get to the bottom of this, You are 100% right,You guys have given me I think all of the possible reasons that why it could be burning oil, Like I heard above that if it doesn't smoke at first but then starts smoking when the engine starts warming up then it is probably the piston rings didn't seat or one may have broke, Mine kinda does that,It won't smoke all that much until the engine gets warmed up, But also somebody said that if the valves are to lose then it can also burn oil,Well the mechanic said he adjusted the valves a bit lose because they would tighten up,Well they may have tightened up but they make quite a bit of nosie ecspecially say I am stopped and I rev the engine you can really hear them, So I am just trying to see when the bike smokes and when it doesn't so I can see what the biggest problem maybe, The reason I haven't gotten it fixed yet is because I have been waiting to see if the rings would seat and they never did I guess or there is something else in there wrong and my dad is just now getting time to take it to the shop, And no my dad doesn't pay for the expenses,I do,Its my bike and I will pay for everything on it. ON a 4-stroke engine there are alot of things that could let it burn oil, Again I am sorry if I insulted you or made you mad Dualsportr, Matt
DualSportr
Member
- Aug 22, 2000
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The person who stated that loose valves could cause smoking meant the valves were loose in the guides (what the valve rides up and down in), allowing oil to seep around them. When you talk about the mechanic 'setting the valves loose' he means that he adjusted the tappets (on the very end of the valve) for a little more clearance. Completely different.
I guess there's two things that frustrate me here, one, is that you don't have a good basic understanding of how your engine works. Not your fault, but it makes it difficult for us (and probably the mechanic) to hold a good conversation about the problems you are experiencing (case in point is the valve 'clearance' discussion above).
The second thing that is a frustration is that everyone here has told you that the rings would have seated by now, and that this is a mechanical problem that needs to be fixed. This has been stated, unequivocally in more than a few posts in the last two months, however you seem to ignore these and still ask the same questions over and over. I guess you're hoping for an answer which won't require another engine tear down and doesn't mean spending more of your hard-earned cash.
I understand your frustration with having to fix a bike which you've already paid to have fixed. However, that doesn't alter the facts.
Fact: the bike is not running correctly, and something must be done to 1. Correctly diagnose the problem and 2. Fix it.
Fact: Neither of those two things can be accomplished online. The engine will have to be disassembled. Period. End of discussion.
Please do update us when you've found the problem and had it fixed. I know we'd all be interested to hear how it pans out.
- Thread starter
- #36
Dualsportr you are right I didn't know what the person mean't when he said that it could burn oil when the valves were loose and right before I read your last reply my dad told me what you said that the valves were loose in the guides, I know alot more about engines now than I did before I got my bike, Do I know every single thing about them,NO I DON'T, I have a good understanding of how my bike works and before I had no idea. When I talk about engines alot of times I know what I mean but I can't put into words what I am talking about, Again I am sorry for making you mad Dualsportr, And Yes I don't want to spend much more money on the bike in the engine dept, I just know that this thing isn't smoking because I did something wrong, I wanted it done right the 1st time just as anyone else would want it done, Ok Dualsportr you said that I keep ignoring the fact that the Rings would have seated by now, I know they would have and they either didn't seat or one broke or they did seat and there is something else wrong, I still think there is a low spot in the cylinder, But the other day I was talking to a guy and he said that when you are boring a cylinder to fit the piston because the cylinder is to small then you can't have a LOW SPOT,So I don't know, I will update you all on the situation when I get it fixed, Oh and Dualsportr the you said that in this 2 months that the rings would have seated,Yes I know but I was only getting to ride like once a week and for 2 weeks I didn't get to ride it so I was giving it time,If I had been riding it everyday I would have done had it in the shop, Sorry for fustrating everyone, Now I feel like a Jerk. Matt
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wow bud,lot of info not much substance.1 1/2 hr old.How much smoke,and when,is bike cold,choke on,does it lessen or dissapear when warm and choke off.What type and grade oil,how full is oil.I am working out my smokin prob at moment with near new xr70 I bought my kids,I`ll let you know how I go.But a couple of things bother me.#1Crap about wiseco taking longer to bed(not true) #2The scratch in bore,are they that careless they couldn`t even pack and wrap it in a rag,says a bit about competency,and if cleared up scratch,I`m guessing with a hone,did they put the said original piston in a sloppy hole.#3Compession loss,rings not fitted correctly or he put it the factory didn`t seat them correctly(wow thats a whopper)If he said after rebuild it was down on compression,and it was due to a poor seating ring,picture this,There is a hardened carbon or chrome alloy ring in a groove in a piston,clearance up and down in groove is variable but average 0.020",it has over 2/3 of its depth in this groove,it has a locator peg where the ring gaps meet.Once on piston and in bore,It has nowhere to go,and if it`s not seated(installed correctly) that hard ring goes snap,ring broken,SMOKE,bore and piston damage.Thats the compression rings.Now the oil rings are a set of 3,top is a thin credit card thickess ring and on the bottom is the same.In between is a wavey shape ring that traps oil in between the wafer ring and the gap in the wave in the middle.Now to not seat(install)correctly means at best it will smoke,but ussually if the wavey one is on top or bottom instead of between thin ones.It is softer and bends,thin ones are easily boken and smoke,let alone bore damage and so on.
It`s a 4 stroke so whipping the head off in front of him for a balls and all inspection is not easy especially for a novice.But with the seating story and the lack of obvious care they take.As well as the lack of support,and owning up to and rectifying mistakes is unexcusable.Do you have a department of fair trading in U.S. if so ring them.Is he a registered and licenced mechanic,ring the Motor Trades Association.I`m afraid that I can`t 100% say what ailes your bike,but a good educated guess would be they snapped a ring,poor install, and probably because they honed it out even more and used same piston set because they were annoyed you caught their carelessness first go and then cared even less when rectifying(if thats what you call it).$10 says it was a 1st year apprentice that actually fitted your gear and they are trying to cover.But one thing is undisputed,they scratched bore,do again,and have rebuilt,no good,take down, rebuild,no good,NOW WHAT? get in touch with someone with some obvious clout like Complaints Officer Honda Motors,fair trading dept. M.T.A. and make a noise and front them and I think after they failed to rectify the problem first go,now you have the choice of repairer and take it elsewhere and give them the bill.CHECK STATE CONSUMER LAWS FIRST.
It`s a 4 stroke so whipping the head off in front of him for a balls and all inspection is not easy especially for a novice.But with the seating story and the lack of obvious care they take.As well as the lack of support,and owning up to and rectifying mistakes is unexcusable.Do you have a department of fair trading in U.S. if so ring them.Is he a registered and licenced mechanic,ring the Motor Trades Association.I`m afraid that I can`t 100% say what ailes your bike,but a good educated guess would be they snapped a ring,poor install, and probably because they honed it out even more and used same piston set because they were annoyed you caught their carelessness first go and then cared even less when rectifying(if thats what you call it).$10 says it was a 1st year apprentice that actually fitted your gear and they are trying to cover.But one thing is undisputed,they scratched bore,do again,and have rebuilt,no good,take down, rebuild,no good,NOW WHAT? get in touch with someone with some obvious clout like Complaints Officer Honda Motors,fair trading dept. M.T.A. and make a noise and front them and I think after they failed to rectify the problem first go,now you have the choice of repairer and take it elsewhere and give them the bill.CHECK STATE CONSUMER LAWS FIRST.
