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put the 801 in some wood for the first time, not to shabby.
[video=youtube;YT2jMnx3c_Y]http://www.youtube.com/watch?v=YT2jMnx3c_Y[/video]
 
Query on an 80

I have an old 80 that's always been a workhorse. On this last job I was using it and the idle went erratic;racing, dying etc. Under full power it would rap up and then dull out and stall. So....it's been a very long time since a carb rebuild....did that and exactly the same thing. I tried a different plug, but will put a new one in shortly. A year ago I pulled the flywheel and examined, sanded and adjusted the point. It looked immaculate in there. So I'm thinking magneto....anyone had similar problems and a solid fix? I'm thinking I should pull the flywheel again and start there....I guess it could also be the crank seals, although it did have great compression....I should check that too again...

Kevin
 
Well, first off, crankseals have nothing what so ever to do with compression, though they can/will make the saw run poorly. I would check the fuel lines by pressure and vac to see if you have a pin hole air leak in one or the other of them. Also when you rebuilt the carb did you clean or replace the final fuel filter in the carb. It is located in a 1/4" hole under the top cover right next to the fuel inlet. Make certain your tank vent check valve is not stuck. Those are the very first places I'd look...definately sounds like fuel starvation to me.
 
Cantdog said:
Well, first off, crankseals have nothing what so ever to do with compression, though they can/will make the saw run poorly. I would check the fuel lines by pressure and vac to see if you have a pin hole air leak in one or the other of them. Also when you rebuilt the carb did you clean or replace the final fuel filter in the carb. It is located in a 1/4" hole under the top cover right next to the fuel inlet. Make certain your tank vent check valve is not stuck. Those are the very first places I'd look...definately sounds like fuel starvation to me.
Click to expand...

Yeah, it doesn't sound like when the crank seals went out on my Husky 2100...just throwing that out there. This would be great if it was a fuel starvation issue. If by 'fuel filter' in the carb you're talking about that mesh screen, no I didn't replace that. I dropped the stripped carb into carb cleaner for a few hrs, flushed and reassembled. I did look at the screen and it seemed clear. I had problems yrs ago with the tank vent, but that was starting issues more than anything. The carb line out of the tank into the carb is fine...but I hear ya....should check down into the tank.

Thanks for the tip on fuel starvation....makes the most sense and I think I'm fishing with the points/magneto...it's going to be simpler than that.

Kevin
 
Bingo Cantdog, you nailed it!:msp_thumbsup: Even though I had full vacuum on my fuel line test, after I cleaned out the tank filter itself, it's business as normal. I was just about to change out that screen inside the carb, but thought I'd give it a pull and test. The vent box is simplicity itself; inside is a formed 90 that goes directly to the carb from the tank. Under the box is a small hole that goes to the top vent/line. I gotta think it was the tank filter since the lines held max vacuum. I had a spare vent box & tank line so I stuck that in for good measure.

I should have looked for the obvious....I know better. I was smarter when I was back in the woods with these things...younger too.:bang:

Anyway, awesome suggestion, thanks again man!!:msp_thumbup:

Kevin
 
hey guy's I just picked up this johnny and wanted to see if anyone knew what model it is? I was thinking it could be an 80 but not 100%. has spark, comp is 160, and a clean cylinder. I put some gas in her and she fired on the third pull, but died 5 seconds later. Then there was gas all over the clutch side of the carb. she wouldn't fire again, thinking shes flooded getting too much gas....anyways let me know what you guys think...
005-1.jpg

004.jpg

002-1.jpg
 
Last edited:
Yep that is an 80. It looks like someone set it up to run a K&N style air filter though. That gas on the clutch side is probably coming from the fuel tank vent. Look to see if the vent is still there or if it has fallen out over the course of the saw's life. It will look like a bunch of little brass rods shoved into a hose. If there is no filter the gas could have sloshed out when you were trying to start it. Normally I would say 160psi is good for a saw, but for an 80 I might pull the muffler and see if there is any scoring. I would say the normal range for psi is 190-220 for these saws.


Nice score!
 
Last edited:
Real1shepherd said:
Bingo Cantdog, you nailed it!:msp_thumbsup: Even though I had full vacuum on my fuel line test, after I cleaned out the tank filter itself, it's business as normal. I was just about to change out that screen inside the carb, but thought I'd give it a pull and test. The vent box is simplicity itself; inside is a formed 90 that goes directly to the carb from the tank. Under the box is a small hole that goes to the top vent/line. I gotta think it was the tank filter since the lines held max vacuum. I had a spare vent box & tank line so I stuck that in for good measure.

I should have looked for the obvious....I know better. I was smarter when I was back in the woods with these things...younger too.:bang:

Anyway, awesome suggestion, thanks again man!!:msp_thumbup:

Kevin
Click to expand...

LOL...Even I get to be right once in a while!!LOL! But really I always go for the easiest stuff first...my main motto is "Never overlook the Obvious" We, as species always want to assume a problem is way more complex than it usually is. Case in point..honda 5.5 mower..always ran great..went to use it....started right up and would run for 30 sec and die. I checked the spark...good spark, ok, fuel issue...so I tore the carb and fuel tank off and cleaned everything and put it all back together...didn't change a thing!! Grrr.. I bet I had that carb on and off a half dozen times, checked the coil air gap...basically went nuts and could not change what this little motor was doing. Finally in desperation I went online and searched "Honda 5'5 running issues" landed on a forum similar to this one and scrolled down the list of issues until I hit one that said "motor starts runs 20 seconds and shuts off" AhhHA!!
Read the posts and end end run was.............Spark plug......NO????? I could bellieve that as I has a nice bright spark.....Monday morning I was at the parts store. getting something else and said WTH gimme a spark plug...worth a shot...lawn's getting pretty high...OL is getting pretty loud. The darn thing started right up and has run perfect ever since!!! I prbably had 8 hrs in fussing whith that thing and the cure was a 60 second fix!!
 
Cantdog said:
LOL...Even I get to be right once in a while!!LOL! But really I always go for the easiest stuff first...my main motto is "Never overlook the Obvious" We, as species always want to assume a problem is way more complex than it usually is. Case in point..honda 5.5 mower..always ran great..went to use it....started right up and would run for 30 sec and die. I checked the spark...good spark, ok, fuel issue...so I tore the carb and fuel tank off and cleaned everything and put it all back together...didn't change a thing!! Grrr.. I bet I had that carb on and off a half dozen times, checked the coil air gap...basically went nuts and could not change what this little motor was doing. Finally in desperation I went online and searched "Honda 5'5 running issues" landed on a forum similar to this one and scrolled down the list of issues until I hit one that said "motor starts runs 20 seconds and shuts off" AhhHA!!
Read the posts and end end run was.............Spark plug......NO????? I could bellieve that as I has a nice bright spark.....Monday morning I was at the parts store. getting something else and said WTH gimme a spark plug...worth a shot...lawn's getting pretty high...OL is getting pretty loud. The darn thing started right up and has run perfect ever since!!! I prbably had 8 hrs in fussing whith that thing and the cure was a 60 second fix!!
Click to expand...

Robin, I have been going through the same thing with the saw my friend dropped off. I cleaned the carb, new fuel lines and filter, and it still wouldn't fire. The plug had nice blue spark but I thought what the hell,and threw another plug in there (the wrong size) and the damn thing runs. Now I just need to get the right plug and it should be golden. Since when do plugs go bad anyways. :)

:cheers:
 
PB said:
Yep that is an 80. It looks like someone set it up to run a K&N style air filter though. That gas on the clutch side is probably coming from the fuel tank vent. Look to see if the vent is still there or if it has fallen out over the course of the saw's life. It will look like a bunch of little brass rods shoved into a hose. If there is no filter the gas could have sloshed out when you were trying to start it. Normally I would say 160psi is good for a saw, but for an 80 I might pull the muffler and see if there is any scoring. I would say the normal range for psi is 190-220 for these saws.


Nice score!
Click to expand...


LOL...What he said!!:cheers:
 
PB said:
Robin, I have been going through the same thing with the saw my friend dropped off. I cleaned the carb, new fuel lines and filter, and it still wouldn't fire. The plug had nice blue spark but I thought what the hell,and threw another plug in there (the wrong size) and the damn thing runs. Now I just need to get the right plug and it should be golden. Since when do plugs go bad anyways. :)

:cheers:
Click to expand...

LOL Yeah I 've had them just not fire under compression but in the outside air fire fine. The one on my mower (I believe) had a crack in the porclean and when cold would fire properly but as it warmed the crack would expand and allow it to fire to ground on the side. It was a sobering event....so now t is the first thing I try when having problems, just to eliminate it...just like I did in 7th grade with my first chainsaw before I knew all this stuff and stuff..LOL!!!
 
It's an 80 alright....just like mine. The tank vent should be a tube that runs from the tank vent 'box' into a hole that goes to the clutch side of the saw. After ignoring the obvious small things and coming in here for a rescue, I would suggest the following; check your fuel lines with a vacuum, check the fuel filter in the tank, replace the spark plug and check your compression. I think my compression runs about 175psi and the saw runs fine. Just as a matter of course since you don't know any history, clean the carb and put in a complete rebuild kit.:rock:

Kevin
 
Real1shepherd said:
It's an 80 alright....just like mine. The tank vent should be a tube that runs from the tank vent 'box' into a hole that goes to the clutch side of the saw. After ignoring the obvious small things and coming in here for a rescue, I would suggest the following; check your fuel lines with a vacuum, check the fuel filter in the tank, replace the spark plug and check your compression. I think my compression runs about 175psi and the saw runs fine. Just as a matter of course since you don't know any history, clean the carb and put in a complete rebuild kit.:rock:

Kevin
Click to expand...

Cantdog said:
LOL...What he said!!:cheers:
Click to expand...

PB said:
Yep that is an 80. It looks like someone set it up to run a K&N style air filter though. That gas on the clutch side is probably coming from the fuel tank vent. Look to see if the vent is still there or if it has fallen out over the course of the saw's life. It will look like a bunch of little brass rods shoved into a hose. If there is no filter the gas could have sloshed out when you were trying to start it. Normally I would say 160psi is good for a saw, but for an 80 I might pull the muffler and see if there is any scoring. I would say the normal range for psi is 190-220 for these saws.


Nice score!
Click to expand...


I was hoping it was an 80, nice.... got it for $50 from some old guy that use to be a faller back in the day. the compression was 160 witch I thought was very good but dam, these go up to 190-220 thats some high compression. when I did the compression test it was kinda hard to pull so I did it only twice, could be higher after I get deeper into it. one weird thing is like I said it kinda hard to pull but if I take out the plug its allot easier to pull??? Could it be because of the very high compression on these old beasts? also the cylinder looks good too me, so here are a couple of pics of the cylinder, and looks like some one been in the carb area. new fuel line... any thoughts?

001-1.jpg


007.jpg


006.jpg


005-2.jpg


004-1.jpg
 
If you only pulled it 2 times you didn't the full compression build up. You should pull it until it stops and I wouldn't be surprised if it is 200. These old JReds have very high compression and you need to be committed to start them. If you take out the plug all the compression will go right through the hole, so that is why it is easier to turn over.
 
PB said:
If you only pulled it 2 times you didn't the full compression build up. You should pull it until it stops and I wouldn't be surprised if it is 200. These old JReds have very high compression and you need to be committed to start them. If you take out the plug all the compression will go right through the hole, so that is why it is easier to turn over.
Click to expand...

ya thats what I thought just need a little more muscle hahah... yep, that was a stupid question but thanks for answering it anyways. hows the cylinder look in the picks?
 

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