SawTroll
Information Collector
Yes, that is what I was thinking of - just didn't remember the name of that valve......:biggrinbounce2:
346XP Piston Diameter Specs (350 Husky Upgrade)
- Thread starter Sonypete
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Yes, that is what I was thinking of - just didn't remember the name of that valve......:biggrinbounce2:
Well I re-tried it with the throttle taped wide open and still the same 110 or so PSI. I also notice my pressure gauge is the one with the valve at the tip, so it should be pulling proper numbers.
After running her through some small pieces of wood, she would sputter and bog out halfway through a cut. I brought it into the garage to check her out and looks like the liquid gasket I used on the transfer port covers are no good, at least on one side. During mid to high RPMS you can see fuel get pushed out to the top just ever so slightly on the one transfer port, thus getting the area wet with fuel.
This might also account for the lower pressure readings I'm getting. Actually on second thought it wouldn't since the compression tests only after the piston has closed over the transfer ports.
Hopefully the local Husky dealer has gasket sets in stock so I can get this taken care of within a day or so. Maybe they will give me a free compression/vacuum test while i'm there. *fingers crossed*
- Pete
After running her through some small pieces of wood, she would sputter and bog out halfway through a cut. I brought it into the garage to check her out and looks like the liquid gasket I used on the transfer port covers are no good, at least on one side. During mid to high RPMS you can see fuel get pushed out to the top just ever so slightly on the one transfer port, thus getting the area wet with fuel.
This might also account for the lower pressure readings I'm getting. Actually on second thought it wouldn't since the compression tests only after the piston has closed over the transfer ports.
Hopefully the local Husky dealer has gasket sets in stock so I can get this taken care of within a day or so. Maybe they will give me a free compression/vacuum test while i'm there. *fingers crossed*
- Pete
ronT2
ArboristSite Guru
I haven't been able to find a part # for the transfer cover gaskets. I had to cut a set out of some gasket material.
Yea not able to find one either. Will have to cut some up tonight.
Hey Guys,
It should be pretty safe to re-use the head gasket on my Husky 350, as long as I clean it off, right?
Also I had removed the bolts for the crankshaft cover part of the cylinder but never pulled it off the plastic base as it was stuck pretty good. Do they use an adhesive type liquid gasket? I just put hte bolts back after noticing there was no need to remove it. Should I be concerned about leakage there?
Anyone think that the transfer port leaking could affect the overall compression readings? Granted there covered up during the up stroke for compression they would release some of the fuel/air mixture when the piston is coming down and forcing it into the upper chamber via the transfer ports. So there would be less fuel and air to compress. Just let me know if I'm grabbing at straws here, heh.
Hey Guys,
It should be pretty safe to re-use the head gasket on my Husky 350, as long as I clean it off, right?
Also I had removed the bolts for the crankshaft cover part of the cylinder but never pulled it off the plastic base as it was stuck pretty good. Do they use an adhesive type liquid gasket? I just put hte bolts back after noticing there was no need to remove it. Should I be concerned about leakage there?
Anyone think that the transfer port leaking could affect the overall compression readings? Granted there covered up during the up stroke for compression they would release some of the fuel/air mixture when the piston is coming down and forcing it into the upper chamber via the transfer ports. So there would be less fuel and air to compress. Just let me know if I'm grabbing at straws here, heh.
Alright I tore her apart again. Used gasket paper for the side transfer port covers. Checked everything again. I noticed the cylinder is still somewhat smooth to the touch but I can see smearing on the exhaust side. I ended up taking my brake honing tool to it again to get a good surface for the rings. Funny thing is the new piston and ring show no signs of causing the cylinder wall aberrations.
After putting it back together I did a compression test and it was 120PSI. She started right up and I did a couple heat cycles while I wait for the air filter to come in since I just ordered on.
Once the air filter was I cut some random logs and honestly she screams through them compared to my father-in-laws craftsman. After about 30 minutes of cutting stuff, I let her cool off so I could get some compression number and check out the cylinder through the spark plug hole. Well looks like the cylinder wall is showing wear signs as before. And she tested at 100PSI, lower then the very first time I had her together because I only heat cycled it then. She has seen some load the 2nd time around.
I put some oil in and tested again and she shot up to 150 PSI easily. So it looks to be issue with the ring/cylinder.
I even screwed the H and L carb adjustments all the way counter clockwise to get as rich of a setting so its getting plenty of oil in the fuel. So its not an issue with over heating.
All in all, even at 100 PSI she rips. For how long she lasts with crappy ring to cylinder seal I can only guess. From how the cylinder shows it don't look to get any worse from the initial 20 minutes of running. I'll keep checking her since I can deal with the current power she has.
- Pete
After putting it back together I did a compression test and it was 120PSI. She started right up and I did a couple heat cycles while I wait for the air filter to come in since I just ordered on.
Once the air filter was I cut some random logs and honestly she screams through them compared to my father-in-laws craftsman. After about 30 minutes of cutting stuff, I let her cool off so I could get some compression number and check out the cylinder through the spark plug hole. Well looks like the cylinder wall is showing wear signs as before. And she tested at 100PSI, lower then the very first time I had her together because I only heat cycled it then. She has seen some load the 2nd time around.
I put some oil in and tested again and she shot up to 150 PSI easily. So it looks to be issue with the ring/cylinder.
I even screwed the H and L carb adjustments all the way counter clockwise to get as rich of a setting so its getting plenty of oil in the fuel. So its not an issue with over heating.
All in all, even at 100 PSI she rips. For how long she lasts with crappy ring to cylinder seal I can only guess. From how the cylinder shows it don't look to get any worse from the initial 20 minutes of running. I'll keep checking her since I can deal with the current power she has.
- Pete
sunfish
Fish Head
I'd run the crap out of her and replace the cylinder if it needs later.
Sunfish,
Thats what i'm thinking. she runs like a bat out of hell with just 100+ PSI and my port job. I won't be using her a whole lot so probably last me as is for a few years.
Can't beat it for only $40 put into her to get running.
- Pete
Thats what i'm thinking. she runs like a bat out of hell with just 100+ PSI and my port job. I won't be using her a whole lot so probably last me as is for a few years.
Can't beat it for only $40 put into her to get running.
- Pete
Don't hone two strokes. You ruined the cylinder.
See I have heard that comment before, but have also heard its fine todo on a 2 stroke cylinder. Honestly, in generality, the cylinder walls surface are no different on a 2 stroke then a 4 stroke engine.
I can't see honing it ever so slightly to get a nice surface so that the new ring will break in properly would cause an issue only on a 2 stroke cylinder.
Rupedoggy explain why its an issue only on 2 stroke engines? I have no problem with being incorrect in my assumption
- Pete
I can't see honing it ever so slightly to get a nice surface so that the new ring will break in properly would cause an issue only on a 2 stroke cylinder.
Rupedoggy explain why its an issue only on 2 stroke engines? I have no problem with being incorrect in my assumption
- Pete
ronT2
ArboristSite Guru
Beside the fact that they are cylindrical in shape and you want a uniform cross hatched pattern to help seat the rings the cylinders on saws are very different. I have yet to rebuild a four stroke that didn’t have plain iron walled cylinders. On the other hand every saw or other small OPE two cycle I’ve had apart has had some type of coating over the aluminum, and it aint thick. If you break through that coating you’ll soon be looking for a new cylinder.
When you said in an earlier post that you noticed a “smear” could you be seeing a spot on in the cylinder where you could have broken through??? Just a thought….
When you said in an earlier post that you noticed a “smear” could you be seeing a spot on in the cylinder where you could have broken through??? Just a thought….
The smear is more like a long streak and only shows after running the engine. So seems to be a product of running the engine. Didn't notice any break through when prepping the cylinder during both assemblies.
- Pete
- Pete
SawTroll
Information Collector
I suspect the cylinder walls will not hold on to the oil as well if polished, but I am no expert on the issue....
Hotdig
ArboristSite Lurker
squish
The squish on my 350 with oem gasket was just over .05
Without gasket was .022
Did you put a gasket under the jug?
If so, I'd remove it and use yamabond 4 or the other suggested sealers.
Gets you more compression.
.02$
The squish on my 350 with oem gasket was just over .05
Without gasket was .022
Did you put a gasket under the jug?
If so, I'd remove it and use yamabond 4 or the other suggested sealers.
Gets you more compression.
.02$
nmurph
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Old thread.
Hotdig
ArboristSite Lurker
TY......... I'm slipping in my old age.
