Help with 1989 gas motor.

[DonoBBD]

Ok so I had a odd back fire so it seemed. I thought it was the intake gasket so I pulled the carb and intake to find everything ok nothing out of the ordinary. So I cleaned up where the fuel pump sits to see if it was where this puff was coming from. Cleaned up all the parts try ed her again and still a puff back fire still. Got in there for a very very good look and it is the crankcase in that area letting out this puff.

So I then see two loose bolts on the back of the motor. Someone at some point changed out the starter. The two bolts that hold the bracket on that hold the crank case together were loose. I cranked them tight but I feel they have pushed the gasket out. (if there is a gasket)

Is there a way I could fix this with out pulling the motor and with out splitting the case apart?

Any thoughts?

Cheers Don.

[mcdave71]

So is it leaking oil already? If no leaks run it as is. If it is a leak, it's hard to degrease a small access in a case and apply sealant. Can be done but is it worth the hardship?

[DonoBBD]

Originally Posted by mcdave71

So is it leaking oil already? If no leaks run it as is. If it is a leak, it's hard to degrease a small access in a case and apply sealant. Can be done but is it worth the hardship?

Well it is kinda odd. It is puffing out oil gas mix but the spot it is coming out is so small it can hardly be seen. It is behind the intake infront of the fuel pump and about a half inch or so. I tightened up the two loose bolts but it didn't fix the leak. I am guessing that there is a crank case gasket then and is pushed out in this small spot.

Is there a crank case gasket?

Don.

[redcloud]

In 89 the early engines were 2PG's and later 89's were the new 3PG and I know that the 3PG's do not have a gasket as I just rebuilt mine. Only a light layer of liquid gasket. Do you have the engine that has the horizontal muffler or the one that has a verticle muffler? Verticle is a 2PG.
You don't mention if anything has been done to the engine or how well it was running before the puffing or during?
Wondering about back pressure from plugged muffler?
Not sure that would give that problem but worth a look see.

[DonoBBD]

Originally Posted by redcloud

In 89 the early engines were 2PG's and later 89's were the new 3PG and I know that the 3PG's do not have a gasket as I just rebuilt mine. Only a light layer of liquid gasket. Do you have the engine that has the horizontal muffler or the one that has a verticle muffler? Verticle is a 2PG.
You don't mention if anything has been done to the engine or how well it was running before the puffing or during?
Wondering about back pressure from plugged muffler?
Not sure that would give that problem but worth a look see.

It was running OK just hard starting. New carb. Muffler is vertical I am sure it is clear as it was working fine. Will double check.

I picked up some green lock tight and blue. Going to loosen off the two bolts that were loose again and drop on some green by the leak. Tighten up the bolts. Then drop on some blue and hope she holds. I have nothing to loose other then having to pull the motor and fix her right if it don't.

Cheers Don.

[redcloud]

Just wondering if you have looked at the top of the piston or did a compression check? If you have a pin hole or bad ring, you could be getting compression pressure to some degree into the crank case and over running the seam. Just a thought as I see you have not did any rebuild on the engine or mention any of that.

[mcdave71]

Originally Posted by redcloud

Just wondering if you have looked at the top of the piston or did a compression check? If you have a pin hole or bad ring, you could be getting compression pressure to some degree into the crank case and over running the seam. Just a thought as I see you have not did any rebuild on the engine or mention any of that.

Two stroke uses the engine case for intake on this doesn't it? So then it's doing what it's supposed to, just leaking.

[DonoBBD]

Originally Posted by mcdave71

Two stroke uses the engine case for intake on this doesn't it? So then it's doing what it's supposed to, just leaking.

Ya see this is how the hard starting started. Low crank case vacuum to pull the fuel/air past the reeds. The timing being off is too advanced or retarded and lighting off the fuel just before the piston is up past the intake port or after. Then I get the puff into the crank case. The reeds will not let the pressure out so the seal takes the hit. This case leak all started from the two case bolts backing out letting pressure push the gasket out.

The electronic ignition conversion and different plug has created this as well as the clutch kit with a bit much back shift.

Cheers Don.