Husqy 395 Big Bore, Good Compression and Low Power.

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If you haven’t then you definitely want to do a pressure/vacuum test. An air leak can create a gutless condition in bigger saws that still run.

Although your carb is probably fine (since you rebuilt it), some rebuilds don’t work out. Try to find a known good carb that you can swap in and eliminate the carb as a possibility.

You converted from 394 to 395. Did you check the pulse track before install? No garbage blocking the port or nipple in the jug? Line isn’t kinked?

Muffler screen is clear?

If all that checks out, you’re probably dealing with a garbage jug. You could try deleting the gasket, cleaning up the ports, even grinding to get better timing, but I would just admit defeat after a failed delete attempt and replace with a quality jug. I just saw an OEM kit on E-bay today for $150 shipped.

Hope you get it sorted.
 
as said above, thats typical of a aftermarket big bore, low power. canyou measure squish clearance? id be curious to see where port durations are. aftermarket kits, especially big bore kits, require a lot of work to get them even close to an oem cylinder.
 
If you haven’t then you definitely want to do a pressure/vacuum test. An air leak can create a gutless condition in bigger saws that still run.

Although your carb is probably fine (since you rebuilt it), some rebuilds don’t work out. Try to find a known good carb that you can swap in and eliminate the carb as a possibility.

You converted from 394 to 395. Did you check the pulse track before install? No garbage blocking the port or nipple in the jug? Line isn’t kinked?

Muffler screen is clear?

If all that checks out, you’re probably dealing with a garbage jug. You could try deleting the gasket, cleaning up the ports, even grinding to get better timing, but I would just admit defeat after a failed delete attempt and replace with a quality jug. I just saw an OEM kit on E-bay today for $150 shipped.

Hope you get it sorted.
If you haven’t then you definitely want to do a pressure/vacuum test. An air leak can create a gutless condition in bigger saws that still run.

Although your carb is probably fine (since you rebuilt it), some rebuilds don’t work out. Try to find a known good carb that you can swap in and eliminate the carb as a possibility.

You converted from 394 to 395. Did you check the pulse track before install? No garbage blocking the port or nipple in the jug? Line isn’t kinked?

Muffler screen is clear?

If all that checks out, you’re probably dealing with a garbage jug. You could try deleting the gasket, cleaning up the ports, even grinding to get better timing, but I would just admit defeat after a failed delete attempt and replace with a quality jug. I just saw an OEM kit on E-bay today for $150 shipped.

Hope you get it sorted.
Yes checked the pulse tube, muffler screen is clear, spark plug is chocolate brown. I'm going g to try a 395 carb. I'm wandering if the 394 had a smaller carb since it has 2 transfer ports and 395 had 4. If the 394 carb is smaller it may not have enough cfm for a 4 piet big bore. Kinda like having a 600cfm on a 455 Pontiac. Just a thought I came up with.
If you haven’t then you definitely want to do a pressure/vacuum test. An air leak can create a gutless condition in bigger saws that still run.

Although your carb is probably fine (since you rebuilt it), some rebuilds don’t work out. Try to find a known good carb that you can swap in and eliminate the carb as a possibility.

You converted from 394 to 395. Did you check the pulse track before install? No garbage blocking the port or nipple in the jug? Line isn’t kinked?

Muffler screen is clear?

If all that checks out, you’re probably dealing with a garbage jug. You could try deleting the gasket, cleaning up the ports, even grinding to get better timing, but I would just admit defeat after a failed delete attempt and replace with a quality jug. I just saw an OEM kit on E-bay today for $150 shipped.

Hope you get it sorted.
Screen is clear as is pulse tube, spark plug is chocolate brown. I'm going to try a 395 carb. Does the 395 have a slightly bigger carb since it had 4 transfer ports vs the 394 having 2 transfer ports. If that's the case I wander if the 394 carb isn't enough cfm for the 395 4 port big bore, kinda like running a 600 cfm on a big block.
 
Yes checked the pulse tube, muffler screen is clear, spark plug is chocolate brown. I'm going g to try a 395 carb. I'm wandering if the 394 had a smaller carb since it has 2 transfer ports and 395 had 4. If the 394 carb is smaller it may not have enough cfm for a 4 piet big bore. Kinda like having a 600cfm on a 455 Pontiac. Just a thought I came up with.

Screen is clear as is pulse tube, spark plug is chocolate brown. I'm going to try a 395 carb. Does the 395 have a slightly bigger carb since it had 4 transfer ports vs the 394 having 2 transfer ports. If that's the case I wander if the 394 carb isn't enough cfm for the 395 4 port big bore, kinda like running a 600 cfm on a big block.
Didnt mean 2 reply twice.
 
as said above, thats typical of a aftermarket big bore, low power. canyou measure squish clearance? id be curious to see where port durations are. aftermarket kits, especially big bore kits, require a lot of work to get them even close to an oem cylinder.
I do not have the know how or tools to measure squish. I'm going to try a 395 carb.
 
Sorry if it’s been mentioned. Did you buy a kit that converts the 394 to 395? The 394 got its pulse through the carb block. 395 gets pulse from the cylinder through a rubber line and to the carb. Does the carb have an impulse line going to the top plate?
 
Checking squish is pretty easy. All you need is some grease, thin solder, and a mic or calipers. 0.018”-0.025” is the sweet spot. Many AM top ends have a squish in the .045” - .080”. Here’s a link.

 
Ye
Sorry if it’s been mentioned. Did you buy a kit that converts the 394 to 395? The 394 got its pulse through the carb block. 395 gets pulse from the cylinder through a rubber line and to the carb. Does the carb have an impulse line going to the top plate?
Yes it was a 395 kit and yes I added the pulse tube to the top of the carb.
 
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