smoking

[ludwig]

hey everybody,i been busy rebuilding carburetors and proud to say they are working great.but i should mention that i also replaced the ex. vales and seals with after market parts.the head gaskets are Honda.on the initial start up i expected some smoke but the left side smokes pretty bad and smells like oil.then i shut it down and waited a while restarted and no smoke .then took a short ride and no smoke. had bike on side stand for 1 minute restarted and its smoking again.back in the shop on center stand restart after 10 minutes no smoke.could it be something other than valve seals?i 'm pretty sure that might be the problem along with crappy valves witch something told me not to do in the first place.so i have learned a very expensive lesson.i just hope that it's not something else but i think putting Honda parts in it would not hurt.any opinions would be great :thanks:

 

[mcgovern61]

Could be your oil is overfilled. When the bike is on the side stand, oil drains into the valve cover and hangs there leaving it there during start up and a lot of smoke. Best thing is to always shut down with the bike upright and left the oil drain for a minute before going onto the side stand and then only starting it while upright.

The issue could be gas leaking down.

 

[ludwig]

no the oil level is fine,filled with 3.4 qts. 10w40.i pulled the spark plugs and they are all clean no oil on them at all.seems like oil is seeping directly into the left side exhaust.i could start it right up no smoke drive a short distance and after making some left turns it starts smoking again.i don't know if i mentioned this but i had Napa clean and install 4 exhaust valves and 8 valve stem seals from Partsnmore, the intake valves were reused.i just hope i'm right by thinking that if i start all over again and by using Honda valves,seals and gaskets would be worth the $600.00 i will have to put into it.

 

[dan filipi]

I run the oil level no higher than 1/2 way in the site glass.
Has stopped this sidestand smoking problem.

 

[Tory]

I cant see what NAPA could have done wrong.An engine is an engine and these heads (other than being shorter) are very much like a car head.
I would search other avenues like fuel/oil/coolant in a muffler before I invested into redoing something that sounds like it was profesionally done already.
Double check your oil level,make sure you turn off your petcock when parked, and do a compresion test for the heck of it.

 

[dan filipi]

Curious, why do you say the exhaust valves they put in are crappy?

Also, what is the history of this motor?

 

[joedrum]

box fan to cool ...run the bike on the center stand watch it till you figure whats up ...it will be level .. thats what id do ...something will make itself known probably

 

[slabghost]

What color is the smoke? If it's black it's burning a bit rich indicating too much fuel. If it's blue it's oil possibly a bit in the exhaust burning off. If it's white it may be condensation in the exhaust. If it smells sweet it is likely coolant from somewhere. Have you checked the trouble shooting chart in your manual? Are you turning off the fuel just before shut down?

 

[ludwig]

i never said Napa did anything wrong. i maybe should have used the word inferior instead of crappy.yes i do turn off the fuel before shutting off the engine.but before i start buying any more parts i will take the advice of running a lower oil level and doing another compression check.

 

[bulldawg]

at times i nave the exact problem but mine smokes out yhe right eide mostly and to a lesser degree out the left side
but it clears up after a while. like to know what you find out.

don

 

[ludwig]

yeah,i am going with my gut and i am going to replace all the valves,seals,belts,and gaskets with all Honda parts.i will try to never use a.m. parts again.when i rebuilt the carburetors i tried keyster brand and the float bowl gasket wouldn't fit also the carb. to plenum o ring wouldn't fit, the pilot screws are usable but i can see a difference in the finish the cheaper one looks cheaper you get what you pay for. so i thought if there is a difference in those parts there has to be a difference in the valves and seals i just put that i now have take out and throw in the trash.but that's alright at least i get to have another shot at it.this is going to take awhile so happy holidays and peace to all

 

[AApple]

Hmmmm...I kinda been following this. I did my head gaskets earlier this summer, and replaced the valve seals then. Up until then, mine had never smoked unless I had ATF in the fuel. Now, however, it does smoke when I first start it every time, and it is using more oil than it used to. I can smell the oil burning when it starts, and you can see it, too. It only smokes for maybe a minute or so, then stops....as far as I know. I can't see a cloud behind me while riding, so....
Now I'm wondering if the valve seals I got in my gasket set are crap, too.... :headscratch:

I never leave mine on the side stand, except to get off....then it goes right up on center. More habit than anything else.

 

[bulldawg]

after thinking about mine smoking out the right bank,it is mostly after using the choke,
maybe the choke is sticking. any comments? is this possible?
MERRY CHRISTMAS AND A HAPPY NEW YEAR TO all.

 

[ludwig]

i think i found the problem.i pulled the left head off which has only 5 miles on it.and i noticed black unburned fuel that leaked from the intake down to the exhaust.i think that may be due to not lapping the valves?it's my own fault for not asking the guy at Napa if they lapped the valves cause they were together when i picked them up and just put them on the bike.

 

[slabghost]

It all might have seated and sealed up in a few hundred miles of running.Maybe not but I'd have run it a while before tearing back into it.

 

[DaveO430]

i think i found the problem.i pulled the left head off which has only 5 miles on it.and i noticed black unburned fuel that leaked from the intake down to the exhaust.i think that may be due to not lapping the valves?it's my own fault for not asking the guy at Napa if they lapped the valves cause they were together when i picked them up and just put them on the bike.

Got my doubts on that. If the valves were not sealing you would have a miss. There should not be any unburned fuel there unless the carbs are flooding over. Also if you will notice the exhaust valve stems are pointing down so oil going up the stem is unlikely unless the cover was full of oil, the seals gone and the guides worn out and there was waaaaaaaaaay too much oil in the engine. Not going to get much down the intake stem either and it would be obvious when looking down in the intake port. I suspect the rings, look at the edge of the pistons for signs of oil and the carbon washed off the perimeter but still present in the center.

 

[ludwig]

i was having doubts about it too.the only reason i suspected the valves is because it didn't smoke like that before they were put in.but i'm wondering if i'm even on the right track.if it were the rings would it smoke constantly?because like i said it wouldn't smoke on the center stand, only after its moving it would start smoking.after parking for 20 minutes on center stand and restarting it would run strong and clean.i checked the floats and they are all the same at 15.5 mm.

 

[Steve83]

The intake is vacuum, the exhaust is pressure. Bad intake valve seals, stems or guides would allow oil into the cylinder, and it usually clears quickly after startup.. If the exhausts are bad, the oil goes into the headers and muffler. When you pulled the head, was there any oil in the exhaust ports and/or header pipes?

A compression test will tell you if the valves are seating, but leaking valve seats won't cause smoke.

If the bike sits higher than normal, or if the side stand or its mount is loose or bent, the bike will lean over more, dumping oil into the left valve cover. While the head's off, put a pan under the engine, put the bike on the side stand and see if any oil flows.

I hope you get this figured out! Best of luck!

 

[mcgovern61]

i was having doubts about it too.the only reason i suspected the valves is because it didn't smoke like that before they were put in.but i'm wondering if i'm even on the right track.if it were the rings would it smoke constantly?because like i said it wouldn't smoke on the center stand, only after its moving it would start smoking.after parking for 20 minutes on center stand and restarting it would run strong and clean.i checked the floats and they are all the same at 15.5 mm.

I can only say that when I adjusted my floats, they did not seal on all of them at 15.5 mm, I had to adjust #3 to 17.5 mm before it would seal. I had to clean my float needles 3 x before they would seal properly. Could be you are leaking gas and not burning oil. I did a leak down test with my carbs by taking them off, filling the tank to the top and putting the carbs on the floor connected by a fuel line run from the petcock. Let them sit for 24 hours and see if they are leaking when full. I then turned them 45 degrees to see if they leaked while moving and they did! Cleaned the needles again and finally got them to stop leaking. All this time, I was having startup smoke. After cleaning and no leaking, no more startup smoke.

 

[ludwig]

i did just rebuild the carbs myself something i have never done before.the floats are probably not right so i will check them a couple more times.i will get back to it after the holidays.thank you all for your help and advice.i sure could use some of that good luck for Christmas HO HO HO