Boggy Spew from '77 Liquifire...

[yellowlab2]

Last night I picked up my first liquid vintage sled, a '77 340 Liquifire. The previous owner has owned it for close to 20 years, and has used it every year but last. He told me that when he has started it, the last few years, it will spew black oily gas out of the exhasut until it is warmed up...so, of cours, I had to try starting it. It started and ran boggy, and spewed like he said.
The only old sleds I've had that act like this had single Sachs motors, that had Tilly carb issues...so I'm thinking that the carbs he has never cleaned are the main issue here...any other possibilities this sounds like, with this particular motor?
Thanks, in advance for your input!
BTW, I will post up a few pics later today...it's not a gem, but it was a great sled for the $, IMO!

[JD600]

First off, Welcome!

I would start with crank seals and a good carb cleaning. If you are not new to vintage sleds, these things shouldn't be new to you. Liquifires are pretty cool. Keep us posted on this, and good luck.

DE

[harleysportster]

First off, Welcome!

I would start with crank seals and a god carb cleaning. If you are not new to vintage sleds, these things shouldn't be new to you. Liquifires are pretty cool. Keep us posted on this, and good luck.

DE

I would also like to add to check for spark on both cylinders.

[yellowlab2]

Really good spark on both sides, but that doesn't mean both sides are running...does it? I thought of this at the guy's house, too...but I won't dig too much deeper until I get the carbs cleaned and fuel lines replaced. Here are a few pics:

[harleysportster]

Bad/leaking crank seals should be replaced automaticly if you do not know the history of any engine repairs. One other thing to mention are worn choke plungers. As cheap as they are, they should be replaced also.

[yellowlab2]

I did a cursory carb cleaning (not what really needs to be done!), and tried starting it, when I got home today...started and ran, but was boggy...when I felt the y-pipe, the clutch side was cool and the mag side was warm! So I did a quick compression test...120/121, so not bad...sprayed premix right into the the clutch side carb and got it to run on both cylinders. It wouldn't stay running, bogged and quit. At least now I'm pretty sure it's a carb/choke issue, and it WILL run right eventually! Nice sounding motor when it was running on both!!

[harleysportster]

it's great that you are narrowing it down. I would look for a stuck fuel inlet needle valve or clogged jets. You will problably find gummy brownish tar inside the carb bowl. With the blended gas that we have today, it doesn't take long to seperate and gum up.

[WinnipegStPaul9]

But you still need to replace the crank seals. Easy on that sled I'm thinking.

DA

[Jimmy]

Looks like its a 1976 model, cause it has ribs on the side of the pan. You can check the serial number on the tunnel and cross reference this with the serial numbers in the model section on this sight.

[yellowlab2]

It IS a '76, I thought I added that to the post with the pics, but I don't see it there now!

[harleysportster]

But you still need to replace the crank seals. Easy on that sled I'm thinking.

DA

Yep, but best if the engine was pulled fro mthe sled.

[WinnipegStPaul9]

But you still need to replace the crank seals. Easy on that sled I'm thinking.

DA

Yep, but best if the engine was pulled fro mthe sled.

Agreed, just trying to make a point.

DA