Sky hawk leaking oil???

[matesrates]

Hi all
I have a 70cc skyhawk engine 2 stroke
It seems to be leaking oil...
Look like its coming out of magneto...Where the wires come out of engine and its hiting the exhaust and smoking up
How can i fix this problem???????
Any comments more than welcome
Thankyou

 

[WildAlaskan]

well the only thing other than a cracked case it could be is a badly sealed seal

those things are not installed very well what you do about that is first take off magneto being carefull taking it off as not to crack the block
then u could either try to evenly press the seal in making it snug it looks like a rubber washer or buy a replacment online and use a new one

i would to use the one yah got a new one aint expensive but its a time killer waiting for parts and such

that should do it

 

[2door]

If there is enough oil to come out around the wires then the magneto cover is probably about half full of oil. That is a sure sign that the crankshaft seal behind the magneto rotor (magnet) is defective. Often they will have been installed incorrectly at the factory and have been damaged by the rotating magnet. This will require replacement. Several sponsors here have crank seals. The mag side is the narrow one. You'll have to remove the rotor and here's where people get into trouble because the rotor can sometimes be a PITA to get off the shaft. The crankshaft where the rotor rides is only about 5/16" in diameter and can be bent by using excessive prying force on one side of the magnet. Its best to use a puller that will apply equal pressure to both sides at once to avoid crank damage. I like Ace Hardware's faucet handle puller. It works like it was made for the job. Once the magnet is off (mark it so it goes back on the same way) You'll see the seal. It is the black rubber thing. It can be pried out with a small skinny tool and the new seal will need to be driven back in the bore with the proper tool. A socket that is just a little smaller in diameter works well. Lube the inside circumference of the new seal with engine oil as well as the crankshaft before driving the new seal on. Reassemble everything and go riding. As long as everything runs good, you'll be okay. Often when the magneto coil gets oil soaked they can and will fail. Be prepared for that and order a new coil when you order the seals. Good luck.
Tom

 

[matesrates]

If there is enough oil to come out around the wires then the magneto cover is probably about half full of oil. That is a sure sign that the crankshaft seal behind the magneto rotor (magnet) is defective. Often they will have been installed incorrectly at the factory and have been damaged by the rotating magnet. This will require replacement. Several sponsors here have crank seals. The mag side is the narrow one. You'll have to remove the rotor and here's where people get into trouble because the rotor can sometimes be a PITA to get off the shaft. The crankshaft where the rotor rides is only about 5/16" in diameter and can be bent by using excessive prying force on one side of the magnet. Its best to use a puller that will apply equal pressure to both sides at once to avoid crank damage. I like Ace Hardware's faucet handle puller. It works like it was made for the job. Once the magnet is off (mark it so it goes back on the same way) You'll see the seal. It is the black rubber thing. It can be pried out with a small skinny tool and the new seal will need to be driven back in the bore with the proper tool. A socket that is just a little smaller in diameter works well. Lube the inside circumference of the new seal with engine oil as well as the crankshaft before driving the new seal on. Reassemble everything and go riding. As long as everything runs good, you'll be okay. Often when the magneto coil gets oil soaked they can and will fail. Be prepared for that and order a new coil when you order the seals. Good luck.
Tom

Thankyou for the detailed information
Just a question how could there be so much oil in a 2 stroke engine???
Am i runing the oil in the petrol to rich???
I use around 300ml 2 stroke motorcycle oil the 5 litres petrol
I only ride this bike on the weekend
Does all the 2 stroke oil sink to the bottom of fuel take if not used for a week??
Thanks again

 

[camlifter]

fuel and oil are getting past the seal, the fuel is evaporating and just the oil is left in the cover. if it's filled up enough to leak out the wires hole it's been doing it for some time.

 

[2door]

I will suggest reducing the amount of oil in your mix. You are currently running approximately a 16:1 mix. This is often recommended in the kit instructions and is not advisable. Prior to a complete break-in period, about two gallons of run time, we like to see a 24:1 mix moving down to a 32:1 after break-in. Use a good quality 2 stroke, non marine oil and clean gasoline mixed (shook) in a clean container, not in the bike's fuel tank.

Camlifter correctly explained why there is only oil in the magneto cover.

As for oil seperation after a prolonged period of setting it would be advisable to shake the bike a little if it sits for days or weeks without being run. Also you should not mix more fuel than you can use in a few weeks. 2 stroke oil/gas mix has a short shelf life and can go bad if it is stored too long. Good luck, hope we've helped.
Tom

 

[matesrates]

I will suggest reducing the amount of oil in your mix. You are currently running approximately a 16:1 mix. This is often recommended in the kit instructions and is not advisable. Prior to a complete break-in period, about two gallons of run time, we like to see a 24:1 mix moving down to a 32:1 after break-in. Use a good quality 2 stroke, non marine oil and clean gasoline mixed (shook) in a clean container, not in the bike's fuel tank.

Camlifter correctly explained why there is only oil in the magneto cover.

As for oil seperation after a prolonged period of setting it would be advisable to shake the bike a little if it sits for days or weeks without being run. Also you should not mix more fuel than you can use in a few weeks. 2 stroke oil/gas mix has a short shelf life and can go bad if it is stored too long. Good luck, hope we've helped.
Tom

Thanks all for the great info
So i am currently still running it in ?????Is it meant to be 500km?? 9 months of riding i only do around
1 km a day on the weekends just for a bit of fun
31-1 and 24-1 mix sorry how much ml of oil per litre is this???
I use motorbike 2 stroke oil

 

[matesrates]

I have taken off the rotor and it seems to be sitting out about 3mm from the face of engine
So i got a larger socket to push in the seal ...I pushed it in about 2 mm under the face of engine than i put all back together
Went for a short ride than i looked it was sitting out again arond 3 mm
Is this right for the crank seal to sit out of the face around 3 mm????

Anyway i ordered i new seal...Just a question what do you guys use around the seal????? Anything??? oil??? lock tite??? rtv silicon gasket maker????
Thanks in adavance

 

[breno]

Usually ur betta off replacing the seal once the oil gets around the outside of it otherwise she'll be nice and lubed up to pop straight back out again.
This skyhawk 70cc from my experience is abit of a hit and miss thing. The last one I had the crank shaft was oscilatting so the seal never stood a chance. The seals do wear out after a while but usually that can be prevented from not revving the guts out of it for extended times. I do use locktite sealer high temp, oil resis. blah blah. That does stop them coming out but not from wearing out so it can make it a bit of a bugger getting them back out..
Where abouts in Sydney do you live?

 

[matesrates]

I have taken off the rotor and it seems to be sitting out about 3mm from the face of engine
So i got a larger socket to push in the seal ...I pushed it in about 2 mm under the face of engine than i put all back together
Went for a short ride than i looked it was sitting out again arond 3 mm
Is this right for the crank seal to sit out of the face around 3 mm????

Anyway i ordered i new seal...Just a question what do you guys use around the seal????? Anything??? oil??? lock tite??? rtv silicon gasket maker????
Thanks in adavance

Can someone please answer this post???
When i fit this new seal do i push it in around 3 mm under the face of the engine than let the lock tite dry???
Or do i push seal in then turn the engine over (not start it) than the seal will sit around 2 mm outside of face of engine than let the lock tite dry????
Is it meant to fit flush to the face of engine in 2 mm or out 2 mm of face of engine
Please someone answer this as i am going to do this on the weekend
Thankyou in advance--------------

Hi there i have a crank seal leaking on magneto side
Oil is coming out of magneto casing oil is driping out of the wires and leaking onto the exhast

I have taken off the rotor and it seems to be sitting out about 3mm from the face of engine
So i got a larger socket to push in the seal ...I pushed it in about 2 mm under the face of engine than i put all back together
Went for a short ride than i looked it was sitting out again arond 3 mm
Is this right for the crank seal to sit out of the face around 3 mm????

Anyway i ordered i new seal...Just a question what do you guys use around the seal????? Anything??? oil??? lock tite??? rtv silicon gasket maker????
Thanks in adavance

 

[skiball83]

Dont use anything around the seal. On your current prob where it wont seat there is probably some of the old seal in the crank area you cant see. You have to make sure that all of it is out. I just did this and it looked like the old seal was out till I compared it to the new one. Realized I should check again and Im thankful I did. Half the old seal and the little wire around it was still in there. Took EVERTHING out and put in the new seal, now no leaks. BTW used a 3/8 socket to drive in the new seal. Use the ratchet side towards the motor to drive it in, and use a smaller socket than the seal..forgot what size I used. Hope this helps. I forgot, the seal should sit inside the crank seal housing, never out. Out means its gonna get eaten up by the magnet. Keep us posted.

 

[tonycar]

Hi all
I have a 70cc skyhawk engine 2 stroke
It seems to be leaking oil...
Look like its coming out of magneto...Where the wires come out of engine and its hiting the exhaust and smoking up
How can i fix this problem???????
Any comments more than welcome
Thankyou

G'Day, just found this thread, I had the same problem but fixed it after a lot of head scratching, had tried all the above solutions with no luck, frustrated and peed off i put this together. Basically all it is, is a cap over the seal to hold it in with RTV silicone to put a little pressure on it to hold it in place [after i had done all the above threads]. This dose work very well and i do it to all my engines just to be on the safe side.
step 1 get some brass paper thin shim. 2 cut template from paper. 3 reproduce it with paper thin shim. 4 bolt down with coil. 5 take off and apply RTV about 1 mm thick just around the pressed mark on the shim and keep it away from the shaft hole, do same to the top of the seal and crank case fit. 6 put back together wet but do not tighten down, make sure it sits below main thick shaft it should. 7 let dry [24 hr]. 8 reassemble as per normal.
I hope this works for you [i know it will] as it has for me.
Good luck

 

[twebster321]

What kind of oil do you recommend using for the crank case? Anyone know of any related articles on this? Your thoughts and recommendations are appreciated!

 

[2door]

What kind of oil do you recommend using for the crank case? Anyone know of any related articles on this? Your thoughts and recommendations are appreciated!

If you have a 2 cycle engine it does not have oil in the crankcase. All lubrication comes from the oil in the fuel mix. If you're talking about a 4 stroke engine we'll need to know what engine you have before we can help you.
Tom

 

[twebster321]

Tom - It's a two stroke 48 cc (GT 2B), just making sure before I begin testing this baby out! Thank you very much, will let you know how it works out during the test run.

ALL THE BEST!!!

-TW