How to tell if it smokes too much ..

Got questions? We got answers....
Post Reply
mgouras
Member
Posts: 6
Joined: 04:57 pm Dec 27 2007
Country:
Location: Montana

How to tell if it smokes too much ..

Post by mgouras »

I just got my 1991 KDX250 back together, and she's still a smoker.
It seems to me like it's too much white smoke (with a light tint of blue). It smokes at idle, and it smokes more whan I rev it.
Can I drain the tranny oil and let it idle to see if it goes away, perhaps ruling out crank seals?
Can i drain the coolant and run for a cupla minutes to rule out head leak (Or is this too dangerous even for a short period)?
The bike has a new piston and rings. It has 190 compression.
It has a new head gasket (cometic).
I'm running amsoil at 40:1.
Jets are 38 pilot, 160 main and 1368 needle on the top clip. Air screw out 1 1/2 turns.
It idles and runs fine, except for the smoke.
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

Main sounds big...

White smoke is water.... what is the temp there?
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
mgouras
Member
Posts: 6
Joined: 04:57 pm Dec 27 2007
Country:
Location: Montana

Post by mgouras »

Its about 25 degrees outside, if that's what you mean.
1991 KDX250
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Re: 'Can I drain the tranny oil and let it idle to see if it goes away..'

No.

Well, you CAN...but it would be a foolhardy move.

You can test for leaks using a leakdown tester device. Basically, attach a pressure/vacuum guage through the oil filler plug (as an example), run the bike, see what happens. Natch...the breather needs to be blocked off. It would help to have a baseline (a reading done when it worked fine). You can use it to guage changes you DO make, too.

Does the bike LOSE tranny oil? If it's enough to show in the smoke, it will show as a loss of fluid.

That said, as Inda said..white isn't tranny oil. Coolant leaks will show as 'white'..and it will smell sweet, too.

A 2-smoke may well have 'white' smoke..especially when it's cold..and 25º is cold.

If you have no other telltales (fluid loss, sweet smell, steam-bathed looking sparky plug), don't worry about it.

imo and all that extraneous baloney............

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
User avatar
Mr. Wibbens
KDXRider.net
KDXRider.net
Posts: 4884
Joined: 02:57 am Nov 07 2004
Country:
Location: Playing in the Poison Oak
Contact:

Post by Mr. Wibbens »

Warning! This member tends to use sarcasm as a regular form of communication. If a post seems offensive, before you panic and fly off the handle, re-read the post and imagine it being said with a sideways grin.
((Bike Profile))
((Pics))
FIVE OUT OF FOUR PEOPLE DONUT UNDERSTAND FRACTIONS
mgouras
Member
Posts: 6
Joined: 04:57 pm Dec 27 2007
Country:
Location: Montana

Post by mgouras »

Thanks guys. Thanks for the feedback. And nice video!
!
mgouras
Member
Posts: 6
Joined: 04:57 pm Dec 27 2007
Country:
Location: Montana

Post by mgouras »

Well, I decided to take off the head to make sure everything looked good anyway. It did, and I saw no evidence of head gasket leaks.
I buttoned it up with a new head gasket -- and promptly snapped off a cylinder head stud! I was using a torque wrench set to 18 ft lbs, so either my wrench is no good or the stud was bad.
I twisted it out with some vise grips, and got a new stud at the hardware store of the exact same 8X40 size. (it's just steel, right?) So i'll get another head gasket and try again. (I understand they are no good once they are squished)
1991 KDX250
User avatar
scheckaet
KDXRider.net
KDXRider.net
Posts: 3740
Joined: 12:09 am Nov 10 2005
Country:
Location: edmond oklahoma

Post by scheckaet »

The same thing happened to me when I did my fork conversion.
if your torque wrench is as good as mine (read cheap), I always keep it at the lowest setting when not in use and when I do use it, I always go 5 lb at a time till I reach the correct torque. If I feel like it should have cliqued already I start over, hope that makes sense.

As for the head gasket I heard some re-use them after applying some copper spray or sumthin like that but never tried it myself.

Wilf
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

I have reused them... get the copper gasket spray if you don't want to buy another gasket.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

If you use a gasket spray..take note of the small round hole in the gasket that 'mates' with an ellipsis kind'a shaped hole in the cylinder/head. Try to remove the sprayed material from the gasket in the ellipsis area. When you don't, that part of the gasket exposed to coolant will take the sprayed material off..to float around your coolant system...get stuck on the rad cap gasket.

I don't know that's a big deal...I've NOT removed the overspray most of the time (and then found the floaters) and don't know that it causes problems...but...metal floaters in the coolant system doesn't seem like a wonderful thing to me.

Good thing you got the stud out! Sometimes they don't come out so good.

Even a good torque wrench loses it's 'tune' after awhile. There are tool shops that calibrate wrenches...........

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
User avatar
TWMOODY
Gold Member
Gold Member
Posts: 752
Joined: 08:10 pm Dec 01 2006
Country:
Location: Southeast , Michigan

Post by TWMOODY »

I have reused head gaskets one time coating both sides with copper coat.
Never had any problems with many miles.
User avatar
Mr. Wibbens
KDXRider.net
KDXRider.net
Posts: 4884
Joined: 02:57 am Nov 07 2004
Country:
Location: Playing in the Poison Oak
Contact:

Post by Mr. Wibbens »

Just don't use Orange High Temp Silliycone!

I never thought I'd ever hear the end of that one! :roll:
Warning! This member tends to use sarcasm as a regular form of communication. If a post seems offensive, before you panic and fly off the handle, re-read the post and imagine it being said with a sideways grin.
((Bike Profile))
((Pics))
FIVE OUT OF FOUR PEOPLE DONUT UNDERSTAND FRACTIONS
GS
Member
Posts: 644
Joined: 11:33 pm Feb 17 2005
Country:
Location: Vancouver area, Canada

Post by GS »

I just use a very thin coating of high-moly grease.....stuff made in the 50's I would guess. :prayer:

Now, someone (anyone) is free to tell me why that is a bad idea :roll:
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

I know folks who use paint.... :? Seems to work.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
Post Reply