2 Stroke Help Needed

[martindavies]

The water in the rad is fine and clear

[KRS1]

The black stuff is more like honey.

Choke is not on, and the RC valve is working fine. I have the owners manual and have checked all the movements / specifications against it. Also while the head was off it was cleaned, made sure it was moving freely and then rechecked once I put it all back together.

I cant see any numbers stamped on the jets? Maybe im missing them but I can buy new jets of the numbers you recommended and try that out. I cant imagine them costing a lot.

One other thing I noticed was when looking through the exhaust port at the wall of the piston whilst turning the engine over slowly a slight amount milky coloured oil on the piston walls below the rings. Is this normal or point to something else?

Numbers are there, just hard to see. If you have the shop manual then the original sizes are in there. Get the part numbers to avoid communication breakdown at the honda dealer.

You have more than one problem. Sounds like a possible head gasket as one of them, hopefully not the cylinder.

Edited May 21, 2011 by KRS1

[Richard-BKK]

Does the engine use engine-oil? Do you need to fill-up the liquid-cooling? If not than the chances are that an little alien, at night unscrews your spark-plug and is peeing in your combustion chamber.... :D :crazy:

Edited May 21, 2011 by Richard-BKK

[martindavies]

Does the engine use engine-oil? Do you need to fill-up the liquid-cooling? If not than the chances are that an little alien, at night unscrews your spark-plug and is peeing in your combustion chamber.... :D :crazy:

I am not sure on the engine oil front as its not my bike, but I know that in the time I have had it or have known it its never needed water to be added. The bike actually runs at a good temperature. Temp reading generally at about a third up the dial, sometimes in traffic during the day it will go up to the mid way point. but never anywhere near the red.

I like the alien idea though... gonna be the cheapest fix

Yes I think it is suffering from a few different issues.

I will take it for a ride to a local bike mechanic and see what he says and ill post what he thinks when I get back.

Cheers

[dumball]

'Richard-BKK' timestamp='1305960919' post='4438690']

Milky-colored fluids suggest a gasket is leaking... cooling liquid mixes with oil and create the milky color you see... As the two-stoke oil mixed in the petrol is probably not enough to create the milky looking fluid you likely have also engine oil leaking... Time to split the engine and replace all gaskets...

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

[Lickey]

MD, take the exhaust off and remove the air filter, fit some ear plugs and start it up, does it rev better now? if so, replace the filter, still revs good? re-fit exhaust, back to 7k revs? you say the exhaust has been cleaned out, ok, lets take that for gospel, Strokers need exhaust back pressure to run nice, but that back pressure can expose a leaking crank seal,

this simple test should show up the problem. dont worry too much about the oil you see in the exhaust port, the pump is delivering at full throttle opening and the engine is not reaching it, normal..

Didnt try this simple test?

[KRS1]

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

Of course not , but a mechanic could have changed the jets in an attempt to lean the bike out when the smoke first started to occur, which results in a hot cylinder, which could then lead to a cracked head, cylinder, toasted gasket which leads to water coming in.

Gotta check everything !

[Lickey]

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

Of course not , but a mechanic could have changed the jets in an attempt to lean the bike out when the smoke first started to occur, which results in a hot cylinder, which could then lead to a cracked head, cylinder, toasted gasket which leads to water coming in.

Gotta check everything !

Gotta check everything,, OP already said the rad coolant is clean and temp shows normal,,,

Gotta read everything too...

[KRS1]

Im getting out of the kitchen, before it turns violent.

Edited May 21, 2011 by KRS1

[koratfreak]

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

Of course not , but a mechanic could have changed the jets in an attempt to lean the bike out when the smoke first started to occur, which results in a hot cylinder, which could then lead to a cracked head, cylinder, toasted gasket which leads to water coming in.

Gotta check everything !

Gotta check everything,, OP already said the rad coolant is clean and temp shows normal,,,

Gotta read everything too...

I not understand wy somuch talking here!

You bring your bike to like a honda shop ore waterver you have,and they have service pakage.

They wil chek everythink ,new oil,gaskets,everythink.

I got 2 honda nsr 150 cc sp proarm and i did it the same.

For the nsr its cost me before 1200 bhat for cleaning everythink oil ect

[dumball]

'Lickey' timestamp='1305999285' post='4439788']RS1' timestamp='1305997301' post='4439746']

'dumball' timestamp='1305989364' post='4439562']

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

Of course not , but a mechanic could have changed the jets in an attempt to lean the bike out when the smoke first started to occur, which results in a hot cylinder, which could then lead to a cracked head, cylinder, toasted gasket which leads to water coming in.

Gotta check everything !

Gotta check everything,, OP already said the rad coolant is clean and temp shows normal,,,

Gotta read everything too...

Any competant mechanic worth his salt would not change jetting to solve an excess oil feed problem , before the cylinder head would crack from a lean mixture , the piston would have a partial seizure in the cylinder as it it the most vulnerable for overheating problems , put it all back to stock and change the cause of the excess oil , the crank case oil seal which is allowing transmission oil to be drawn into the engine compartment , simple job , simple fix .

[dumball]

'Lickey' timestamp='1305999285' post='4439788']RS1' timestamp='1305997301' post='4439746']

'dumball' timestamp='1305989364' post='4439562']

There is no engine oil , that is a separate system , the transmition oil will enter the lower end through a leaking crank case seal , a very common problem on 2 stroke engines , no way jetting of any kind can cause all of the excess oil you have entering the combustion chamber . I suggest you take the machine to a competent mechanic who works on 2 strokes and have that seal replaced , it should not be expensive as it is a straight forward job . Too many cooks in the kitchen .

Of course not , but a mechanic could have changed the jets in an attempt to lean the bike out when the smoke first started to occur, which results in a hot cylinder, which could then lead to a cracked head, cylinder, toasted gasket which leads to water coming in.

Gotta check everything !

Gotta check everything,, OP already said the rad coolant is clean and temp shows normal,,,

Gotta read everything too...

Any competant mechanic worth his salt would not change jetting to solve an excess oil feed problem , before the cylinder head would crack from a lean mixture , the piston would have a partial seizure in the cylinder as it it the most vulnerable for overheating problems , put it all back to stock and change the cause of the excess oil , the crank case oil seal which is allowing transmission oil to be drawn into the engine compartment , simple job , simple fix .