Gx200 clone smoking problem

[J.S.@SMS]

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.

 

[anickode]

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?

 

[J.S.@SMS]

The breather tube is still connected to the intake. There is some oil in the air filter, but the carb is clean.

 

[bob58o]

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...ct_id=114/category_id=13/mode=prod/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."

 

[itsid]

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

 

[Randy H]

I believe the GX200 only comes with a seal on the intake valve. And for fun one lash cap on the exhaust valve.

 

[J.S.@SMS]

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.

 

[bob58o]

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/pdfs/honda/gx120-gx160-gx200-assembly-guide.pdf

 

[itsid]

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

 

[J.S.@SMS]

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.

 

[bob58o]

Is a possible that a blown head gasket might also cause smoke?

 

[J.S.@SMS]

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.

 

[bob58o]

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.
https://www.youtube.com/watch?v=LUN2z8yZvQM

ADDED:
Perhaps that won't detect a gasket that isn't blown all the way out.????

 

[J.S.@SMS]

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.

 

[J.S.@SMS]

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.

 

[landuse]

I hope it runs better after all the maintenance

 

[bob58o]

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.

 

[J.S.@SMS]

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.

 

[J.S.@SMS]

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.