Search

GREAT RIDES & STAYS!
Fab Ads
Previous Thread
Next Thread
Print Thread
Rate Thread
Burning oil like crazy #154959 05/04/24 06:42 PM
Joined: Sep 2020
Posts: 3
T
Telstar2112 Offline OP
Junior Member
OP Offline
Junior Member
T
Joined: Sep 2020
Posts: 3
Long story short, ran an 07 XT225 out of oil and damaged piston and cylinder. The small dregs of oil that remained in bike at drain were thick like molasses. Must have been run dry a long time. Cleaned everything out and flushed as much as possible and installed new piston , rings and cylinder and gaskets from cheap ebay kit. Checked ring clearances, compression is ok at about 145, not great but I think ok, all went together well. Bike starts right up, but then a minute or so later starts pumping out smoke like a smoke machine, fill the yard in a minute. Seems like as soon as it warms up.

Took it apart 2 more times trying to find something wrong, replaced all the gaskets and O-rings as I suspected one of the o-rings along the cylinder head bolts was somehow allowing oil to slip into the cylinder. Also replaced valve stem seals mainly since they came in the kit. Also ran it a few times replacing the oil and filter in between to try and flush the engine clean.

Same exact result. Runs great, smokes like crazy, way too much to ride, would burn up all the oil quickly anyway.

Some questions:
There is good oil flow to the top end at purge screw along right rear cylinder head bolt but what if return for this oil was clogged? Anyway to check that? THe oil was very thick so a clog somewhere is a possibility but it is certainly pumping as a ton is getting into the cylinder somehow.

Quite a lot of air blows out of crankcase vent hose, the one that goes to the air box, is this normal?

Same if I remove the oil filler plug, lots of air blows out of there, is that normal?

For this amount of oil/smoke is it most likely still getting in by the head gasket from the cylinder head bolt path? It is a lot of smoke!

I also vaguely remember , when cleaning sludge out all the oil paths that I could see and access, at one point feeling like the small screwdriver I was using may have pushed through something that maybe it shouldn't have went through. I don't remember exactly, as it was last year when I worked on this previously. Is there any thin diaphragm near the oil filter area that I could have pierced? Or maybe a hole that was blind but very thin at the end that I pierced and could be screwing up the oil path or pressure? I did not see anything looking online and it is only a vague memory?

I'm getting better at this teardown but is a lot of work and I am at my wits end as to what is going on.

Any help is greatly appreciated.

Steve.

Re: Burning oil like crazy [Re: Telstar2112] #154963 05/05/24 06:52 PM
Joined: Jun 2013
Posts: 4,168
peejman Offline
Platinum Member
*****
Offline
Platinum Member
*****
Joined: Jun 2013
Posts: 4,168
Sounds like your cheap ebay kit is to blame. The compression isn't terrible but is low for a rebuild. Perhaps the compression rings aren't fully seated yet and the oil ring isn't seated at all. The cylinder may be oversize or out-of-round.

Are you using synthetic or conventional oil? Engine break-in must be done with conventional and switch to synthetic later.

Last edited by peejman; 05/05/24 06:52 PM.

This shall pass, be still and know.
2006 XT225, UNI filter, ProTaper bars, MSR handguards, SS front brake line, Shinko 241's.
Re: Burning oil like crazy [Re: peejman] #154964 05/05/24 07:07 PM
Joined: Sep 2020
Posts: 3
T
Telstar2112 Offline OP
Junior Member
OP Offline
Junior Member
T
Joined: Sep 2020
Posts: 3
Since I wrote that above I did recheck the compression and it is more like 155, but I guess it could still be the problem. I did put in synthetic 15W-50 but I can swap that out and run it with regular oil. It is possible there is just something wrong with the kit but that compression isn't too too bad. Maybe I'll try and find another kit or see what the actual Yamaha parts cost but since I am not sure what damage may be done to the whole gearbox from running it out of oil I am reluctant to put too much $ into it.

I will also bring the head into work where we have a machine shop to see if the head is warped or anything like that.

I did open the oil fill on another single cylinder bike while it was running and there was a ton of air pumping out of that one as well so I guess that part is normal.

Thanks,
Steve.

Re: Burning oil like crazy [Re: Telstar2112] #154966 05/06/24 09:02 PM
Joined: Jan 2004
Posts: 6,623
Muniac Offline
Platinum Member
*****
Offline
Platinum Member
*****
Joined: Jan 2004
Posts: 6,623
Compression at 155 PSI isn't great but OK. Our bikes measured around 147 PSI @ 10k miles and didn't use oil. I'm wondering if oil is being ingested through the intake value guide or breather tube. Could oil be getting into the exhaust port somehow? If it's post the cylinder the plug won't look fouled. We ran Mobile I 15W-50 in our bikes and never had any problems. Conventional oil was used for several thousand miles before switching. Good luck running this problem down.


Evolve & Simplify
Be There or Be Nowhere! A Few Adventures & Video
Re: Burning oil like crazy [Re: Telstar2112] #154969 05/07/24 11:35 AM
Joined: Jun 2013
Posts: 4,168
peejman Offline
Platinum Member
*****
Offline
Platinum Member
*****
Joined: Jun 2013
Posts: 4,168
Good point... could be bad valve seals. If it sits for a bit between starts, a good bit of oil could leak through. But I'd think the smoke would subside after a minute or 3 instead of only beginning then.

Are you letting it idle to warm up? If so, I feel sure the rings haven't seated. There's different theories on engine break-in procedures, but it does need some load to maximize cylinder pressure and get the rings to seal up. Given how much smoke you're seeing, there's probably too much oil in there for the rings to seal. I suspect it needs to come back down, get cleaned thoroughly, refilled with conventional oil, and try break-in again. New rings wouldn't be a bad idea.

Last edited by peejman; 05/07/24 11:37 AM.

This shall pass, be still and know.
2006 XT225, UNI filter, ProTaper bars, MSR handguards, SS front brake line, Shinko 241's.
Re: Burning oil like crazy [Re: Telstar2112] #154970 05/11/24 12:17 AM
Joined: Sep 2020
Posts: 3
T
Telstar2112 Offline OP
Junior Member
OP Offline
Junior Member
T
Joined: Sep 2020
Posts: 3
Thanks guys, I will check those things. Initially after first assembly, I started it right up and let it idle. This first time it was still winter and cold out and exhaust coming out was nice and clean until it warmed up, then the smoke started. Now that it is warmer out it starts after only about 20 seconds or so. Interesting about the oil getting right into the exhaust, maybe a crack or something. I will check into that removing and examining the head and also check the plug for fouling. I have revved the bike up here and there but not very much. I could try that too to seat the rings but since the compression wasn't too bad if figured the rings may be OK. I did do the valve seals but not guides and they "seemed" OK but I did not measure them. But the smoke is not immediate but after a small delay so it is not the usual valve seals kind of thing. Hopefully I'll find some time this weekend to tear it back apart.

Re: Burning oil like crazy [Re: Telstar2112] #154972 05/12/24 08:07 PM
Joined: Mar 2022
Posts: 114
flyinhawaiian968 Offline
Member L1
*****
Offline
Member L1
*****
Joined: Mar 2022
Posts: 114
Did you happen to get a bunch of oil down into the exhaust itself when you disassembled the engine? That could be the reason why it doesn't immediately smoke upon cold start, it has to heat up the exhaust to get it smoking. While this would be pretty loud, you could remove the muffler from the pipe, start it up and see if it still smokes. If it doesn't, chances are there's a bunch of oil in the muffler that starts smoking once the exhaust heats it up enough. I'd probably check the manifold pipe for oil too before testing this theory.

Compression sounds decent enough for this bike to run okay, so I'd put more attention into the valvetrain leaking somewhere. You say you ran it out of oil, I assume you seized the engine enough to warrant the cylinder/piston replacement. If so, you may have damaged the valves too, which could cause it to leak into the cylinder/exhaust port. I think that's where I'd spend my time inspecting once I determined its not just the exhaust coated or filled with oil.


1992 XT225

Web & Site Search
Google
 
Custom TO Customer
Specialty Resource and DONATE
Fab Ads
Boardcaster Updates

Board Upgrade: Board upgrade to V7.7.3 has been completed on Monday Feb 3rd 2020. Ride safely. Enjoy the new software!

Who's Online Now
0 registered members (), 23 guests, and 1 spider.
Key: Admin, Global Mod, Mod
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Top Posters(All Time)
Reggie 11,645
Muniac 6,623
alexd 5,915
Az4x4 5,074
Moto Psycho 4,684
peejman 4,168
kris 2,366
JerryH 2,152
Paul49 2,114
Doc250 1,643
Forum Statistics
Forums38
Topics16,843
Posts151,359
Members6,020
Most Online279
Dec 6th, 2019
Newest Members
Steve855, Thauch, NoahA, JimmyPNW, Fothi Lajos
6020 Registered Users
May
S M T W T F S
1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31
Powered by UBB.threads™ PHP Forum Software 7.7.3