DA 85 question

[nesikachad]

I just can't seem to get ahead here.

My 3W crapped out with a bad reed and now my DA85 is acting goofy.

Went to the field last night and the motor floods out while trying to start it. I pull the plug and it just pukes fuel everywhere like it'd been stabbed in the neck or something.

The local DA guru suggests that I check to see if the seat on the carb is acting up. I pull the fuel line from the tank and blow in it. He said that if the needle is bad it'll let me blow air into it. Well, it didn't so that was a good thing. (right?)

I dry off the plug and we get it fired. Fiddling with the needles to get a nice transition. Everything seems to be good then we notice that fuel/oil is built up on the outside of the case at the seam. It's weeping passed the seal between the two cylinder case halves. The motor died a couple times on the transition after a long idle so we go back to fiddling with the needles a bit. while turning it over we hear this peculiar whistle/wheezing sound. Similar to the sound a blade of grass makes when being blown between your thumbs. I think it's the cylinder case pushing air through the case halves.

GRRRRR! This thing was sent back to DA and completely overhauled less than a month ago. I've had less than ten flights on it. It's never been overheated or suffered a lean run. I know these are good engines, I think I'm just an unfortunate victim of circumstance. The local "DA Guru Guy" has one on a QQ bipe that is an absolute rocket ship. The thing just screams.

I'm tired of pulling engines and mailing them all over the fricken country so I'm going to fix this myself which leads to my real question here; I used Yamabond for years on dirt bikes and it's what we use to seal up cases on the vintage H/D bikes here at the shop. It would seem plausible that it should work for this too.

Any reason not to use it?

[brycesteenburg]

I have done it before with Hondabond. Pretty much the same stuff. Worked great and sealed. It was made to seal two machined surfaces together and be resistant to gas and oil. Try it. Like I said it worked for me.
Bryce

[jamesrxx951]

i cant see why it wouldn't work it designed for 2 stroke engines. i used it on my 2 stroke yamaha snowmobile. and it worked. should be faster then sending it back in and waiting. i think it need to set for 24 hrs to fully cure thought right?

[WOODisGOOD]

	Quote: Originally Posted by nesikachad
	I just can't seem to get ahead here. My 3W crapped out with a bad reed and now my DA85 is acting goofy. Went to the field last night and the motor floods out while trying to start it. I pull the plug and it just pukes fuel everywhere like it'd been stabbed in the neck or something. The local DA guru suggests that I check to see if the seat on the carb is acting up. I pull the fuel line from the tank and blow in it. He said that if the needle is bad it'll let me blow air into it. Well, it didn't so that was a good thing. (right?) I dry off the plug and we get it fired. Fiddling with the needles to get a nice transition. Everything seems to be good then we notice that fuel/oil is built up on the outside of the case at the seam. It's weeping passed the seal between the two cylinder case halves. The motor died a couple times on the transition after a long idle so we go back to fiddling with the needles a bit. while turning it over we hear this peculiar whistle/wheezing sound. Similar to the sound a blade of grass makes when being blown between your thumbs. I think it's the cylinder case pushing air through the case halves. GRRRRR! This thing was sent back to DA and completely overhauled less than a month ago. I've had less than ten flights on it. It's never been overheated or suffered a lean run. I know these are good engines, I think I'm just an unfortunate victim of circumstance. The local "DA Guru Guy" has one on a QQ bipe that is an absolute rocket ship. The thing just screams. I'm tired of pulling engines and mailing them all over the fricken country so I'm going to fix this myself which leads to my real question here; I used Yamabond for years on dirt bikes and it's what we use to seal up cases on the vintage H/D bikes here at the shop. It would seem plausible that it should work for this too. Any reason not to use it?

Chad,
I dont see that the engine has ever been in for service unless it came in under a different name. Let me know if you need a new gasket and I will be glad to send you one.

[nesikachad]

Garrett Knight. It was his plane prior to the 4th of July weekend. You guys went through the motor and got it back to him the Thursday before.

I fixed the problem by the way. Wasn't the gasket. The case bolts that hold the front/back half together were loose.

Two of the bolt were almost ready to fall out.

Runs like a watch now.