Go Back   DIY Go Kart Forum > Building Plans And Advice > Engines & Clutches

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 09-14-2018, 04:20 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default Gx200 clone smoking problem

I have a Honda GX200 clone that is smoking like crazy. I cannot see any sign of damage to the cylinder wall or the rings. However it is definitely burning oil. Also I noticed that there is only one valve seal in the head. Any advice on what could be causing this would be greatly appreciated.
Reply With Quote
  #2  
Old 09-14-2018, 05:08 PM
anickode's Avatar
anickode anickode is offline
Senior Member
 
Join Date: Apr 2010
Location: S.E. Michigan
Posts: 1,572
Thanks: 51
Thanked 680 Times in 475 Posts
Default

I usually attribute a major smoking problem to bad influences and poor coping mechanisms.

If the cylinder walls and Piston rings are good, the oil is either coming from the head or the breather. Is your breather still routed to the intake? Oil in the intake/carburetor?
__________________
"Well that would be a bomb."
Reply With Quote
The Following User Says Thank You to anickode For This Useful Post:
65ShelbyClone (10-26-2018)
  #3  
Old 09-14-2018, 05:18 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

The breather tube is still connected to the intake. There is some oil in the air filter, but the carb is clean.
Reply With Quote
  #4  
Old 09-14-2018, 11:32 PM
bob58o's Avatar
bob58o bob58o is offline
Sick, Tired, and in Debt
 
Join Date: Jan 2016
Location: Under the Rothschild Whip
Posts: 7,339
Thanks: 3,184
Thanked 2,096 Times in 1,651 Posts
Default

Any modifications done to the engine?
Hot cam? Ratio Rockers? These tend to lead to worn out valve stem guides.
http://www.badasscars.com/index.cfm/...rod/prd114.htm

"The next thing to observe is WHEN it smokes. If it smokes under acceleration, it is telling you that it smokes when cylinder pressures are high, which points at the rings. If it smokes under deceleration, it points at the valve stem seals. A really good symptom when valve seals (or guides) are shot, is when the engine smokes real bad when first started-up in the morning, but them stops smoking shortly after. This is because it takes some time for the oil to seep down the long valve guides, and sitting for several hours or over night allows ample time for this oil to seep down and into the combustion chambers, which would burn (and smoke) upon start-up."
__________________
Paper money eventually returns to its intrinsic value: Zero
Reply With Quote
The Following 2 Users Say Thank You to bob58o For This Useful Post:
pearl111 (10-25-2018), Randy H (09-16-2018)
  #5  
Old 09-15-2018, 05:48 AM
itsid's Avatar
itsid itsid is offline
Moderator
 
Join Date: Jul 2013
Location: Ruhrpott [Germany]
Posts: 9,040
Thanks: 1,239
Thanked 3,834 Times in 2,858 Posts
Default

a missing valve stem seal will cause smoke;
so first refit new seals and see if that fixes your problem.
(yes, I'd replace the remaining one with a fresh one while you're at it.. just to not take any chances)

'sid
__________________
Jokes about german sausage are the wurst.
Reply With Quote
The Following 2 Users Say Thank You to itsid For This Useful Post:
pearl111 (10-25-2018), Randy H (09-16-2018)
  #6  
Old 09-15-2018, 08:13 AM
Randy H Randy H is offline
Senior Member
 
Join Date: Oct 2016
Posts: 703
Thanks: 701
Thanked 381 Times in 293 Posts
Default

I believe the GX200 only comes with a seal on the intake valve. And for fun one lash cap on the exhaust valve.
Reply With Quote
The Following 2 Users Say Thank You to Randy H For This Useful Post:
bob58o (09-15-2018), pearl111 (10-25-2018)
  #7  
Old 09-15-2018, 08:18 AM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

What about if it smokes at idle, when accelerating, and when decelerating, and does not stop smoking. Could this be a sign that the rings, valve seals and valve guides need to be replaced.
Also to answer bob58o's question, I have only removed the governor, and that was after the engine had started smoking. Other than that the engine is stock.
Reply With Quote
  #8  
Old 09-15-2018, 10:08 AM
bob58o's Avatar
bob58o bob58o is offline
Sick, Tired, and in Debt
 
Join Date: Jan 2016
Location: Under the Rothschild Whip
Posts: 7,339
Thanks: 3,184
Thanked 2,096 Times in 1,651 Posts
Default

Quote:
Originally Posted by Randy H View Post
I believe the GX200 only comes with a seal on the intake valve. And for fun one lash cap on the exhaust valve.
The 212 Hemi's I've had were that way. Only 1 seal. On the intake side.
https://www.lsengineers.co.uk/media/...mbly-guide.pdf
__________________
Paper money eventually returns to its intrinsic value: Zero
Reply With Quote
The Following User Says Thank You to bob58o For This Useful Post:
Randy H (09-16-2018)
  #9  
Old 09-15-2018, 11:14 AM
itsid's Avatar
itsid itsid is offline
Moderator
 
Join Date: Jul 2013
Location: Ruhrpott [Germany]
Posts: 9,040
Thanks: 1,239
Thanked 3,834 Times in 2,858 Posts
Default

Quote:
Originally Posted by Randy H View Post
I believe the GX200 only comes with a seal on the intake valve. And for fun one lash cap on the exhaust valve.
hmm,
if the lash cap looks like the stem seal that might be, but I remeber two such hats on my clone
(I can't tell for sure if they both had a lip, since I haven't removed the springs [just set the lash])

odd, but sure they save every penny possible...
so I guess you could very well be correct

Well then,
air filter.. the air filter could be the cause if it's dripping wet,
TEST: remove the air filter, cover the air intake with a fresh clean hankerchief (cloth, not tissue!)
if it stops smoking after a few seconds, it WAS the air filter..
SOLUTION: clean the airfilter and it's box, soak it in fresh oil and squeez as much oil out as you can.. recheck!
if it's not, we can move on

TEST: carb, sometimes that's not oil but unburned fuel mixed with nasty schmoo from the carb bowl..
so clean the carb bowl and turn lean the engine out until it barely stays alive then back up 1/8th of a turn.
have it as lean as possible in idle for our test.
Now allow it to idle for a minute or two;
if it stops smoking it's been your carb.
else.. we move on!

remove the exhaust (it itself can collect oil and smoke)
testrun the engine, and if it stops smoking...
clean the exhaust internally (brake cleaner works well) while having it off.
if it doesn't we need to move on

And for that the engine will have to be disassembled
check the valve seats (worn out as bob said?) still properly pressed in?

piston rings can be installed incorrectly (order, orientation or flipped upside down)
IIRC the oil ring is a sandwich of three indicidual rings and the scraper (second) has a nasty barely visible taper (bigger diameter needs to point down)
make sure order is correct as well as none is flipped align the ring gaps 120 apart

if you can measure your bore it might be worn and in need of oversized rings already.
and you have it apart anyways.. so you might want to fix that.

And if it still keeps blowing out smoke now, I'm out of clues *shrugs*

'sid
__________________
Jokes about german sausage are the wurst.
Reply With Quote
The Following User Says Thank You to itsid For This Useful Post:
Randy H (09-16-2018)
  #10  
Old 09-15-2018, 12:29 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

It isn't the air filter because I already took it off to see if that was the problem and the engine is still releasing white smoked.
I already removed and cleaned the carburetor but it does have some high speed tuning issues.
It may very well be the exhaust because when I removed it I set it on its side and some oil came out.
It isn't likely that the rings are improperly installed since I have never removed them.

I forgot to mention this earlier but I bought this engine new on a 2014 Baja Warrior MB200gc and only put about 15 to 20 hours on it before it started smoking. So there may be some extremely cheap components in this engine.
Reply With Quote
  #11  
Old 09-15-2018, 12:55 PM
bob58o's Avatar
bob58o bob58o is offline
Sick, Tired, and in Debt
 
Join Date: Jan 2016
Location: Under the Rothschild Whip
Posts: 7,339
Thanks: 3,184
Thanked 2,096 Times in 1,651 Posts
Default

Is a possible that a blown head gasket might also cause smoke?
__________________
Paper money eventually returns to its intrinsic value: Zero
Reply With Quote
  #12  
Old 09-15-2018, 01:02 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

Quote:
Originally Posted by bob58o View Post
Is a possible that a blown head gasket might also cause smoke?
Not sure but I have noticed that the head gasket looks strange where it separates the combustion chamber and the area where the push rods are.
Reply With Quote
  #13  
Old 09-15-2018, 01:05 PM
bob58o's Avatar
bob58o bob58o is offline
Sick, Tired, and in Debt
 
Join Date: Jan 2016
Location: Under the Rothschild Whip
Posts: 7,339
Thanks: 3,184
Thanked 2,096 Times in 1,651 Posts
Default

Quote:
Originally Posted by J.S.@SMS View Post
Not sure but I have noticed that the head gasket looks strange where it separates the combustion chamber and the area where the push rods are.
You can check the head gasket by spraying some soapy water and pulling the pull starter.


ADDED:
Perhaps that won't detect a gasket that isn't blown all the way out.????
__________________
Paper money eventually returns to its intrinsic value: Zero
Reply With Quote
The Following 2 Users Say Thank You to bob58o For This Useful Post:
Nosandwich (09-16-2018), Randy H (09-16-2018)
  #14  
Old 09-15-2018, 02:11 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

I will need to examine the head gasket closely, but that might be it. I can hear a very faint hissing and there is a spot on the heat shield under the head, right below where the head gasket would be, that has what appears to be oil that has been burnt onto the shield by the engine heat.
Reply With Quote
  #15  
Old 10-25-2018, 02:35 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

Hey everyone. It's been over a month so I figured that I'd give you all an update.

I cleaned the muffler, the air filter, and the carburetor, none of which helped. So I decided that I might as well pull the engine apart and inspect each component.

I didn't need to check the head gasket for a leak, because when I pulled it out there was a flat spot in it where there is supposed to be a ridge. Made a note to self to order a new gasket kit and continued disassembling.

I removed the side cover and shortly then after the cam, crank, rod and piston. Cam and tappets showed signs of only slight wear, but the rings were wore out and apparently installed incorrectly (oil ring where the oil ring goes, center ring on the top slot and upside down, and chrome faced ring in the center slot), which is odd since the engine was new and I never removed the rings. So I added new rings to the list.

Moving on to the head, I removed the rockers and the valved. Neither seemed worn. I ordered two new valve seals (they work on the intake and exhaust and fit like a glove on both).

After the parts arrived I honed the bore and re-assembled the engine. The parts that I ordered are:
New ring kit
New gasket kit
New valve seals
New crank seals
New carburetor (Ruixing)

I also completely removed the remaining half of the arm that rides on the governor (originally chopped it off just below the part that holds it in the block leaving about 1/4" in the block), drilled the hole out to 1/4" and tapped for a 5/16-24tpi bolt that I had lying around (same bolt size that predators use for the side plate and crank). I then bent some bailing wire into a throttle linkage and used the governor spring (the hd one) as a throttle return spring.

I will post some pictures as soon as possible. And I will see if it will run after I order a new lash cap, or as Honda's engineers like to call it a "exhaust valve rotator cap." Mine seems to have gone AWOL.
Reply With Quote
The Following 2 Users Say Thank You to J.S.@SMS For This Useful Post:
itsid (10-26-2018), landuse (10-26-2018)
  #16  
Old 10-26-2018, 01:06 AM
landuse's Avatar
landuse landuse is offline
Moderator
 
Join Date: Nov 2010
Location: Pietermaritzburg, South Africa
Posts: 16,353
Thanks: 1,671
Thanked 3,085 Times in 2,512 Posts
Default

I hope it runs better after all the maintenance
Reply With Quote
  #17  
Old 10-26-2018, 01:25 AM
bob58o's Avatar
bob58o bob58o is offline
Sick, Tired, and in Debt
 
Join Date: Jan 2016
Location: Under the Rothschild Whip
Posts: 7,339
Thanks: 3,184
Thanked 2,096 Times in 1,651 Posts
Default

Quote:
Originally Posted by J.S.@SMS View Post
And I will see if it will run after I order a new lash cap, or as Honda's engineers like to call it a "exhaust valve rotator cap." Mine seems to have gone AWOL.
Lash caps, Hemi rocker arm shaft E-clips, split style keepers,...
Poof - right into the Ether.
__________________
Paper money eventually returns to its intrinsic value: Zero
Reply With Quote
  #18  
Old 11-02-2018, 06:55 PM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

I got the lash caps today. So I will be reassembling and starting the break in either tomorrow or Sunday. I also got an autolite ar3910x plug for the engine.
Reply With Quote
  #19  
Old 11-19-2018, 11:27 AM
J.S.@SMS J.S.@SMS is offline
Senior Member
 
Join Date: Sep 2018
Location: Weeki Wachee Fl.
Posts: 168
Thanks: 26
Thanked 29 Times in 27 Posts
Default

Sorry it took so long, but I ran into some issues. I forgot that i had to cut the fuel line because it was stuck to the old carburetor. Then when I went to get now fuel line I bought 1/4" instead of the correct 3/16" which led to a fuel leak. And I was also out of oil. So after getting the new line and oil, I reassembled the engine yesterday. And it started up. It did smoke for about 5 minutes, however I think that was because the rings weren't seated yet, and I did put a few drops of oil in the cylinder prior to starting the engine. And after the 5 minutes it stopped smoking completely. And its actually smoother than when it was new.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 11:25 PM.