Burning oil

I changed my oil yesterday. New filter. I even got the rear drain plug. Today, it starts smoking. White. Bike runs fine (though I sm not planning on riding it until I figure out what the problem is).

You may recognize this from my last oil change when I put too much oil in and it overflowed in to the airbox. I'm pretty sure I put the right amount in this time, so what's the story?

 

what kind of oil did you use and can you see a small bubble in the top of sight glass ON THE CENTER STAND

 

Yamaha 20w-40 sae

yes. I could see the bubble when the bike was on it's center stand.

 

Oil smoke is unmistakenly blue in color. White smoke is water either vapor caused by moisture in the exhaust system, a head gasket/water jacket leak in a water cooled engine or possibly automatic transmission fluid being drawn into the engine.

So, lets see. You are air cooled, you don't have an automatic transmission so it must be water vapor either from condensation in the exhaust system, or from water contamination in the crankcase burning off.

Does the oil look like oil should look or does it have a milky appearance? I can't guess how you could get enough water in the crankcase oil to make your bike smoke white.

 

Often lots of oil burning looks as white smoke. Blue is not always the colour.. And in the absences of water or ATF.. likely .
Suggest either a fresh bore/rings/ bearings etc OR a bottle of Lucas Oil Conditioner (overpriced STP It will stop the oil burning, letting you use the bike for a fair while to come.

 

Just ride it till it blows and then buy my parts bike. Engine has 4,000 miles. pm me.

 

I would ride it a bit and see if it clears up. Could be oil or ??? in the exhaust collector or muffler cans.

 

wamaxim - I'm pretty sure it's oil. Smell, etc.

jared - I've got a parts bike sitting in my garage (thanks, though) so I imagine I'll turn to that once riding weather is no longer available. I would like to keep riding it while it's nice, though.

Anyone else lend any praise for Lucas Oil Conditioner? Worth it?

OK, so here's the weirdest part: Over the last couple of days, I've been taking the bike out for short trips. It does fine for a while at the beginning of the trip (no smoke). Then, once it heats up, it starts smoking. It will ALSO smoke if I tip the bike (sharp turn) a fair amount.

Please help. I'm not sure where I should be looking. ANY IDEAS?

 

How many miles are on it? A bad valve stem seal could lead to the symptoms you're describing. What do the plugs look like? Is one quite oily?

 

Fitz, why come you don't answer my PM?

 

MILES: 21,600
SPARK PLUGS: All of them are black. One and three have white on the tips. There seems to be a bit of oil seepage, though coming from the plug holes - all of them. This ring any bells?

It would seem that there is something really wrong with my engine. I would like to fix it myself. What I need to know is how I begin.

Do I take the entire engine out of the bike? As long as I'm getting in there, what else should I do while I'm in there? What parts should I order? Or should I wait to see what I find once I open her up?

 

First off, let's do some basic diagnosis. The motor could still be full of oil from the overfill episode.

Do a compression check; post results. With only 21K on it, I wouldn't think rings would be an issue unless the motor was badly rusted inside at some point, but let's find out.

My best guess without more diagnosis is "dead" valve stem seals. Not a horribly expensive or unusual procedure; you can take the opportunity to clean, decarbon and lap the valves at the same time IF that's the fix.

 

Sounds good. I'll do a compression check and post within the next couple of days. Thanks, Fitz.

 

In the future ... don't bother with the "Rear Drain Plug"
There is a chance it might fracture ... leaving you in a lurch.

Do a simple little test.
Warm-up the bike.
Take it for a ride.
Have somebody follow you and watch your exhaust.
Have them remember how and when it smokes and how bad.

 

Thanks, Rick. As soon as I make friends with someone with motorized transportation (all of my friends ride bicycles), I'll make them do this.

Hey, I just read this forum: http://xjbikes.com/Forums/viewtopic/p=1 ... tml#170905

...and I'm thinking that this might be part of my problem. Is it possible that the symptoms I have described could be gas in the engine? I DID notice a gas smell when I drained my oil, but I thought that was just the bike. If so, I assume I need to reset my float levels. Anything else?

 

If you even THINK you have gas in the crankcase, change the oil.

A bike that's filling its crankcase up has two problems, one with a float or floats that aren't shutting off PLUS something going on with the petcock whereby it isn't shutting off either.

You can check quite easily: pull your oil filler cap off with the motor COLD and stick your nose in the hole. You'll smell gas if that's happening. I'm perpetually worried about the possibility, so I "sniff the crankcase" everytime I add oil or forgot when I last did it, or come back to the bike and realize I left it on PRI for whatever reason. You should NOT smell gas, just oil.

I still think the motor could be full of oil, puddled in the breather maze, etc., and still burning it out. It doesn't do it cold because the oil isn't trapped somewhere it warms up right away.

Or maybe the overfill wasn't totally "operator error" and we have a two-pronged problem.

I'm assuming the bike ran reasonably OK with no oil burning symptoms prior to the overfill episode?

If you're going to keep riding it a bit during the diagnostic phase, fit a new set of plugs and let's see how fast they soot up.

 

It's possible that all of these are problems. It's going to take a couple of days until I can get you compression numbers. Talk to me about what kind of danger I'm running right now with the gas in the crankcase.

My bike's going to explode, isn't it?

 

Gas in the crankcase dilutes your oil and then bad things happen to bearings and the like. If there's gas in the oil, CHANGE the oil. You don't need to change the filter every time until you get the problem figured out, but don't run the motor with gas-diluted oil in it.

Your bike won't explode, but you also don't want to wreck your main bearings.

 

Fair enough. Fitz, I can always count on ya. Thanks. I'll change the oil and check the compression on Friday (my next day off). Get back to you then.

 

Alright. Help me with my memory here: I'm about to do a compression check. I was prepared to just take out the spark plugs one-by-one and screw in the gauge and turn the bike on. I let it turn over a couple/four times and then take the reading for the highest compression. THEN, I remember that there was some other step in there. I had to disconnect something electrical. So I searched for the thread but can't seem to find it. Anyone want to throw me a bone?

 

Remove Plugs (All)
Unplug Ignitor
FULLY Charged Battery
Throttles held WIDE Open
Neutral
Install Tester Hose to No.-1
Turn-over Engine / Observe & Record Gauge information.
Write-down observations.
Continue to 2, 3 & 4

 

OK. I can do all of this... except how do I "unplug" the ignitor?

 

Lift the Seat or remove the Side Cover and locate the Box.

Remove the two Plug-in's ... No Heavy Lifting.

 

FINALLY! Had a day off and ran the compression check:

1 70psi
2 85psi
3 95psi
4 70psi

Also, in case it helps, spark plugs were as follows:
1 white
2 fine
3 white
4 black

Thanks for the diagnostics help.

 

If you had all 4 plugs out, throttle opened up, and battery boosted, guess what- - you either have a bad compression tester, or a bad motor. Anything under 80 usually doesn't light off at idle.

Now you can put a tablespoon of oil in each hole and see if the compression comes up or not.
If it does = bad rings
if it doesn't = bad valve seating, possible valve adj. or warped valve.

 

$hit. Didn't open up the throttle. Thanks, TIME. Funny, too, because Rick JUST told me to do that.

Will do again and get back to you.

 

OK, new, ACTUAL readings on those cylinders (with it warmed up, and with the throttle open:
1 = 120
2 = 100
3 = 100
4 = 85

Bigfitz, I just put in new spark plugs. Will let you know how it goes. Please give me some advice with this new knowledge.

 

I get 147's on XJ's and I hit 180 on a lawn mower, due to different cam timing, so, what's the highest you've seen on that gauge?
You need better numbers. Something's not right.

Then try the oil.

 

The gauge is brand new. First item I have done the test on. I will change the oil (and put a table spoon of oil in each cylinder) tomorrow and let you know what I get.

 

Bump

 

What happened with the re-test with a tablespoon of oil in each cylinder?

Are you sure your new gauge was fully seated in the plug holes and you didn't have any leaks anywhere?

Try a different gauge, seriously. I own two (they're cheap) for exactly that reason. {side note: the one I have that's 30+ years old was made in the USA. Try to find one nowadays...}

You HAVE checked and adjusted your valve clearances?

 

sounds like the valves need adjusted, or worst case at least one cylinder needs rings.

i had a similar problem on my kz a few months ago, turned out to be a bent valve. try the easiest first, check the valve clearances.

after that re-check ur compression. if ur compresion doesnt come up over 110-120(should be closer to 130+, but will run ok with 110-120) you will at minimum have to pull the head, and if you do this, do a full engine rebuild, you will appreciate not having to pull the engine apart again for a good long time if its properly cared for.

 

Alright,

Here are the readings AFTER dropping some oil in each cylinder:
1 = 150
2 = 150
3 = 180
4 = 120

So, quite a bit higher than without the oil.

I believe my valve clearances are all good. I checked, replaced, and rechecked valve clearances about 4 months ago.

What's next?

 

Oh. I also wanted to get back to you on the spark plugs. Put new ones in yesterday and drove around for a bit afterwards and today. All of the plugs look good except for 3 which is dark black.

 

bump

 

Based on the 3 compression tests and the black plug, you have. . .

Bad Rings on #4, maybe caused by your gas-in-oil episode (??)

It might get a little better with continued driving, but if the cylinder is scuffed and scored it's gonna need work to make it right.
Alot of work.

 

Unfortunately I tend to agree.

The readings you got from #4, especially its "improvement" once oiled, tells us that #4 definitely has a ring problem; oil won't cause that big of a change if it's a bad valve. #3 probably just needs a valve stem seal.

I would pull the head and assess the extent of the problem; then decide if it makes more sense to rebuild or look for a motor to swap.

 

I think I would like to rebuild. Now that I have a garage and a thirst for knowledge I will be able to work on it all winter. Could you talk me through the broad strokes of rebuilding?

 

Try running 20/50 Oil in it.
See if that slows down the consumption issue.

 

Sure; Pull the head, and have a look at the cylinder walls. Pull the jugs and measure the bores (or have them measured) for roundness and wear, top and bottom.
Then a decision can be made about using the original pistons with new rings, re-sleeving, boring and using bigger pistons, etc. Parts availability and expense also begins to come into play.
The head will also need to be torn down and inspected, the valves lapped and valve stem seals replaced (if the valves are OK.)
Since you're going to have the motor apart that far, you might consider flipping it over, splitting the cases and replacing the primary chain tensioner while you're at it. This step is NOT necessary as part of the upper-end rebuild we were discussing.

 

I will try 20/50. Do you think I will do significant damage if I ride the bike until November before beginning this work?

 

Not any that the rebuild won't fix, unless the #4 cylinder has suffered something really horrible. I would run 20W50 and take it easy with the right wrist. Give yourself a new 7K redline for now.

 

Sounds good. I'm mainly puttering around the city so I don't usually bring the rpms too high anyway.

I'm a bit bummed, because I just bought a bunch of 10W40, but that stuff will keep until next Spring, right?

Also, do I need to replace the filter when I put in 20W50? I just replaced it 6 weeks ago.

 

If you leave the Caps on the Bottles ... your grandchildren can use the oil, later.

Run 20/50
You don't need a new Filter.
Watch the Oil Level and Color.
Top it up as needed.
Open the Airbox and remove the Filter.
Wipe the INNER Shelf clean with Paper Towel or Tissue.

If the 20/50 lets you go without having to add too much Oil that good.

IF you start USING Oil frequently ...
CHECK
That inner Airbox Shelf.
If you problem get to the point where the Airbox Shelf is getting nasty... you got to SHUT DOWN because you risk Throwing a Rod.

 

Great. Thanks. I'll go get some 20/50 right now.
I have NO IDEA where I would be without you guys. BTW - Rick, thanks for the clutch adjustment how to. It worked REAL nice.

 

After thinking about this- - you have nothing to lose by trying to free-up whatever bunged up the rings in #4 by dropping in a couple tablespoons of SeaFoam and letting sit for a couple days, then run it out, and do it again. Several times over.

I have had gasoline enter the crankcase of cars with mechanical fuel pumps before, and here at XJBikes there have been many people who ended up running gas in the oil, and nobody had a catastrophic failure.

When you consider how easy it would be to try this, to free up a possibly stuck ring, and also change-up to the thicker oil for now, as opposed to pulling your engine apart, I'd do it !!

Also try- - Marvel Mystery Oil, PB-Blaster, Kroil, Holy Water. . .

 

Great. I've got some Kroil, some PB Blaster and some Seafoam lying around. I'll give the Seafoam a try first.

 

An update -
I changed the oil today (also cleaned out the airbox - which wasn't bad - with a paper towel) and put in 20w50. It smokes. A lot.

I'm going to try the Seafoam in a bit but I was wondering if this smoking can tell you any more about the bike.

 

It smokes now, because you just poured all that oil in. . .
You are now scheduled for a mandatory 40 mile highway cruise.
Then break out the SeaFoam.

 

I'm beginning to think you have two problems.

One, we know the rings on #4 aren't the greatest, but that plug isn't sooting up so that's probably not the source.

#3 is sooting up pretty badly, IIRC.

I think a valve stem seal on #3 is gone and that's what's causing the smoke. That or there's still a puddle of oil somewhere that hasn't burned away yet.