Still smoking left side DAMIT

[funky]

Hi all ran the bike up properly today I am still getting smoke out the left pipe starts clear then after about a minute it smokes not to bad on idle 1100 rpm but when i throttle it it gets worse nothing right side I am thinking rings probably. should of checked when I had the engine out but found that a valve stem oil seal was shot and thought that was the problem.
Could it be air leakage from the carbs or floats timing chain seems correct tension is good.

when removing the plugs the electrodes outer and inner are black and shiny but the face around the base of the threaded section of the plug is silver and clean on both sides tells me i am a little lean rather than rich. Not sure what to do but do not want to rush and pull the engine again. I am thinking of changing the mixture screws as they are missing the little "o" rings and washers that sit below the the small spring for new ones from mikes and new carb rubbers engine side.
As I said the timing is in the "f" mark fitted Pamco high powered system new ATU solid state regulater rectifire iridium plugs new head gasket re seated valves that where a good fit in the valve guides no wobble side to side, compression was good 145psi and 140psi. I am wondering if the previous owner who had rebuild the engine popped the oil seal upside down or has not staggered the ring gaps.
read a thread last night where another chap from England took his engine out four times due to the same problem and it was rings .... could it be my piston sleeve on the left is scored DAMIT bike runs really nice can get good low idle speed adjust the carbs mixture does not cut out and rides good too wondering if i just leave it for a while and see if it settles ,,, not sur what to do
All the best Funky

 

[Jbinnington]

At risk of stating the obvious, you will need to dismantle it to find out. You ask "could it be...?" Yes it could but from this distance the best that can be done is to say look at this or that.
You are going to need to dismantle, inspect and repair/replace

You are satisfied its oil smoke and not a very rich carb, perhaps the cold start circuit on one carb is jammed open or a missing pilot jet?

Start with a carb overhaul, and go from there. It would be unusual for one cyl to fail only. Unless of course it's been messed with...

 

[funky]

I am going to go to the carbs first just ordered two new mixture screw kits because that is not right there are "o" rings missing from both. When lock the mixture screw down and screw them out half a turn, the bike runs ok ,,, the book says 21/2 to 3 turns on the 34s I checked for air leaks with carb cleaner on the seals but they seem fine.I will take the engine out again but only when i am sure thats all it can be.
Also the pipes have silencers in them with wadding and i know that the left one got soaked in oil and fuel when i lost my left cylinder before i fitted the Pamco so it could be burning that off.
Thanks for the reply all the best

 

[funky]

Hi all hope you are well just to update you i have posted a video of the smoking left cylinder any suggestion would be greatly appreciated ,,,, here is the link

Ok the situation is this I thought about this with my limited knowledge and what has become apparent is that the carbs have the same issue on both sides I.E the mixture screws both of them are missing the rubber "O" ring and small washer so why is only the left side smoking It cant be a carb problem I stripped the carbys down and re-checked all the components all the jets everything. things are pointing to the engine having to be pulled again.
All the best funky

 

[TwoManyXS1Bs]

Hey, funky. White smoke out the exhaust, like in your video, can come from a variety of sources, but your video looks like it's from the rings.

These engines also have a history of pulling oil from the camchain tunnel thru the headgasket, from warped surfaces. Search for "leakless engine assembly". Coupla threads on that:

http://www.xs650.com/forum/showthread.php?t=13212
http://www.xs650.com/forum/showthread.php?t=30318

Usually, when there's ring blow-by, you'll get oil mist coming out the crankcase breather, more during acceleration. Could try to fashion some sort of filter/trap to the crankcase vent tubing (like a wrapped rag), and see if it gets wet.

With ring blow-by, you can have bad rings and cylinders, stuck rings, non-seating rings (glazed cylinders). Some ideas in these threads:

http://www.xs650.com/forum/showthread.php?t=32451
http://www.xs650.com/forum/showthread.php?t=29279

Of course, the proper approach is to consider a top-end overhaul.

 

[ridgerunner1965]

have you run it enuf to burn out the oil and fuel yu say was trapped in the left pipe wadding?

 

[HooliganCycles]

I see you did a compression check, a leak down would tell you a lot...or pour a little oil in the cylinders and see if compression comes up, that would indicate ring trouble

 

[Jbinnington]

Good point, give it a good run to burn off your spilt oil. Does the plug on the affected side foul?

 

[funky]

Hi all thanks for the reply Interesting stuff I did not use 1104 as stated and can see how this could be the issue i am pulling the engine out and going again probably next week.
the cleanliness was there last time.
Need to be more meticulous in my approach and learn not to rush I am to eager to get things done thats where I feel down need to take my time and check with you fellas for advise.
Thanks chaps

 

[funky]

Good point, give it a good run to burn off your spilt oil. Does the plug on the affected side foul?

both the plugs come out the same carbon on the electrode base rings on the plugs silver and clean left plug has a little oil on it

 

[funky]

Ridgerunner I have done about 80 miles on it so its probably had enough time to burn that off i would think could be wrong though, thanks for the suggestions,

 

[chizler62]

Typically you see if its a guide seal that it will not always smoke. When it gets hot out or after engine warms etc. A worn valve guide will always smoke however. You can take off the left valve cover and run the bike a bit. If you see a lot of oil "mist" than perhaps rings, shoot some extra oil in the cavity and see if the seal picks it up?

I have seen a few of these forums where XS650 owners have put gasket sealer on the entire head gasket. This isn't the proper way. The head gasket is made only were there are certain areas for the sealer. If applying sealer to entire gasket the areas where the sealer is suppose to be, around cam chain tunnel, will not have enough compression and won't be as effective as designed. etc
You could be pulling oil from that area. I have seen this twice on customer's bikes in the last few years.

And honestly "no wobble" really isn't the way to check valve stem clearance. lol

 

[TwoManyXS1Bs]

...And honestly "no wobble" really isn't the way to check valve stem clearance. lol

Here's the Go/NoGo test from the '78 service manual.

 

[chizler62]

Before competent techs, tools, training etc Using a dial indicator was used, that procedure to my knowledge has been replaced

Posted via Mobile

 

[TwoManyXS1Bs]

The purpose of the valve guide is two-fold:
First, to keep the valve aligned so that the valve head will properly and instantly seat at the closing moment, which also reduces flutter/settling and uneven seat wear.
Second, to pass some of the valve heat to the head casting.

Valve guides wear in an hourglass pattern, especially in rocker-arm configurations. To determine the ability of the guide to maintain this alignment, using bore gauges, requires multiple ID readings, and a little geometry to derive the valve head's potential misalignment. Each reading, either stem OD or guide ID, will introduce certain errors, from the instrument's measurement tolerances and the operator's deft touch. These accumulative errors stack up.

There's two methods to determine measured clearances of a shaft in a hole.

First is the "derived" method. Measurement of the shaft OD, which includes the two measurement errors of instrument tolerance and operator technique, is subtracted from the hole's ID, which also includes the same two error factors. The resulting value will then include at least four errors, a significant tolerance factor. It gets worse if working with 'hourglass' wear patterns. Plus, this method makes no provision for bore and shaft "straightness", another error of unknown magnitude.

Second is the "direct" method, which would use feeler gauges, 'rocking', drag-fit measurements, air gauge, ...etc. The "direct" method also includes the instrument and operator error, but only one of each, not two or more of each. The "direct" method is faster, and potentially more accurate.

Before competent techs...

When was that? Before it was all shipped overseas? Does that include grammer and diction?

A competent tech school would have taught this...

 

[funky]

Hi dudes how are you all hope your well.... Took my engine out again today
and guess what I found this...
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I think Twomanyxs and and your friendly neighborhood 5twins hit the nail on the head LEAKAGE
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Twomany posted a link where 5twin recommended using a sealant around the oilsways and of course the Camchain well

[/QUOTE] did not see that should of asked
I Award you both the CDM


These are my bores your advise on these would be appreciated

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well I am going to have top of cylinder head and head skimmed and have the valve guides checked along with the valves stems and seats all by the book this time I am pretty sure that the leakage was the issue. will also have piston rings and piston checked but i will do my own checks first so i can learn and then get a pro in to see what he thinks my mate budgy who has been a motorcyle mechanic for 35 years and has done work on my CBR 600 sf1 sports

Dont forget chaps let me know what you think and thanks for all your feedback if any of you require andy help with Psychiatric matters i will only be to ready to help
All the best funky

 

[funky]

CLOSE UP OF BORES
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What the verdict or

 

[scabber]

Looks like a re bore might fix it. What do the pistons look like. A machine shop can tell you better. Depends weather you can hone and new rings.

 

[TwoManyXS1Bs]

Ditto with scabber. Bores need work. If they're clean-up honed enuff, they'll probably end up out of spec, especially with worn pistons, so bore job and pistons/rings likely. If head and cylinders are skimmed flat, can forego the sealer trick...

 

[chizler62]

When was that? Before it was all shipped overseas? Does that include grammer and diction?

A competent tech school would have taught this...

Isn't grammer a singer? or grammar is the singer? lol
My point is that a lot of manuals and info in the 70's and early 80's were written for the tech who hadn't ever been trained. Like HonTec, MMI, AMI or whatever they're called. IMO if the 78 manual was written today for exactly the same bike with todays trained techs, OEM tools, etc the procedures would be different.
You'll notice todays OEM manuals are written without the simple procedures "how to check cable free play" etc because it's written for a competent tech.