OT - Need help quick, engine rebuild question.

jmkarcz · 10/25/2007, 09:55 PM

I am re building the $%^##@ leaf blower, and recv'd the parts tonight. I have it all the way apart, and am replacing the piston thingy, and the piston chute thingy (thing the piston goes up and down in...) I can normally replace old parts with new parts, but there were directions in the new piston parts that have me confused.

It reads: be sure to heat the new piston too 150 degrees F. and to clean the rust inhibator from the piston with alcohol or solvent.

I scrubbed the piston down with alcohol and a solvent, nothing really came off... but why should I heat the piston up, that will make it larger, and not fit into the other part I bought, the chute? do I really need to heat it up?

If anyone could nudge me, I'd like to get it back up and running tonight, it would save me an hour or two tomorrow...

Jason

Limpit · 10/25/2007, 10:01 PM

J,
Heating it up would expand it if anything but not much at 150. I am thinking that they may have you do that to bake out any inhibitor you missed. It could also be to heat treat the piston for some reason but again 150 is not much. Just stick it in your oven to be on the safe side.
I am not really much of a 2 cycle mech. so maybe that is what it is all about.

BTW, the "chute thingy is called a cylinder.

jmkarcz · 10/25/2007, 10:03 PM

I could hit it with the torch for, oh, say, a whole 25 seconds, but it's smaller than 1/2 a "C" battery. I'll do it, but I was kinda wondering why...

Limpit · 10/25/2007, 10:05 PM

Just stick it in your oven.
I would not hit it with a torch, you cannot regulate the temp. that way.

jmkarcz · 10/25/2007, 10:07 PM

I spose... I already had it on... I'll do that....

Thanks

Limpit · 10/25/2007, 10:15 PM

Hey wait..I just thought of a great idea.
Put it in the microwave, it will cook faster.

jmkarcz · 10/25/2007, 10:19 PM

jmkarcz · 10/25/2007, 11:57 PM

Does anyone have a fool proof way of adding exactly the right amount of oil for their 2 cycle engines? I had alot of time to think while I tore this apart, tried to fix it, put it together, - did not work, ordered the parts and repeated the process... and the only explanation I can come up with is that I do not remember if the oil in the 4oz container was completely full or not. I usually add a little less than the full amount, as 40:1 is 3.2 oz to 1 gallon. this way I err on the heavy amount, but maybe I should get a measuring container or something... do they make such a beast that is intended for this type of application?

BTW it runs again. in case anyone doubted me Scott.

J

Thanks Limpit, I had just enough time to crack a Root beer while the piston was in the oven.

Fishcrazy06 · 10/26/2007, 12:09 AM

I dont know if this is a good thing or not but I was always told my a number of different 'old timers' its better to add a little extra oil than a little less. I have always done that. Like I said dunno if its good or bad but I have never had a problem doing it this way.

Eric

jmkarcz · 10/26/2007, 12:17 AM

Ironically, I to was told that by an old timer... I think looking back the 4oz of oil may have been 3, but it's hard to tell as that was 2 weeks ago...

bigreef74 · 10/26/2007, 05:46 AM

Ok here is my thought on 2 cycle oil and octane rating on fuel.

First all 2 stroke oil is different, each manufacture use different additives to their oil. This is because each oil is maid for a specific brand of small engine and the make up of their internal engine parts pistons, cylinder wall sleeve. â€œchuteâ€

Next part. Heating the piston expands it to release the sealants. If you were to look at a piston under a microscope it would look like the rock mountains.

87 octane verses 93 octane

I use 93 octane in all my lawn equipment, because the 93 octane has more lubricants and less impurities.

In my vehicles I use 3 tanks of 87 and the fourth it 93 octane to help clean out the carbon and the also lubricate the vale train.

On another note make sure you install the piton rings correctly.

Always use break clean to remove sealants and grease from parts break clean is the most cost effective metal cleaner that dose not leave a residue.

Hope this helps.

Mike

yaitisme · 10/26/2007, 07:36 AM

I'm not sure that there are more lubricants or less impurities in 93 octane... there is more octane though. I use premium, from stations that don't add Alcohol, in my small engines also. The octane number drops over time so 87 octane is only going to get lower, not good. I also avoid the alcohol because it tends to absorb water over time. In modern cars, 10% alcohol is no big deal and higher octane is just a marketing ploy unless it is needed by an engine with higher compression (common on Nisson's).

As far as heating the piston, Mikes answer sounds right. Must be a reason the Man. wants you to do it, so why not?

2 cycle oils measurement.... for that some of an amount, I use a 2 cycle oil seringe (my spell check can't even help me here). I actually use a turkey injection seringe for the 100 to 1 full synthetic oil I use (@ 1.3 oz to a gallon all though I use an even 2 oz).

Your problem is more than likely on the carb side. If the piston moves a 2 cycle engine will typically run. If the carb. is slightly off or the reeds are damaged your screwed.

I agree with Mike on 2-cycle oil too, not all will burn right in all engines. I used to buy what ever was on sale, but stopped doing this after have mixed (pun intended) results. When I got into snowmobiling, I did a ton of reading on 2-cycle oils and now only use two types... Mercury Premium in my outboard and Amsoil 100-1 (Amsoil 2-cycle injection oil in the sled until it stopped snowing LOL) in everything else. No more problems and the 100-1 is easier on the environment. I wouldn't mix up any new 2-cycle oil this late in the season unless you have something to use it in over the winter.

If your in the area, stop by any fill your blower up with some of my gas. I use it through out the year so it stays relatively fresh. I could also get you a couple oz. of 100-1 to try it yourself.

jmkarcz · 10/26/2007, 09:52 PM

I did go buy a bottle of 2-cycle oil from/with some well known label on it, like Briggs and Straton... I really was just sucked in by the handy pre measure cup on the top... You know, the ones that you release the cap, and as you squeeze, the oil/fluid flows up along the side thru a tube and fills the cup to the level you squeeze to... when it's empty, I'm gonna just get some other economy size 2 cycle oil with a brand name and refill it... it'll be a pain, but I like the thought of knowing that I DID get the 3.2 oz in the gallon (and maybe a bit more and how much more.) Here's what I ended up fixing... because I believe the oil was a bit to lean... it ran for 45 minutes just fine... it's the only explanation.

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kiowascout · 10/27/2007, 04:15 PM

that is one fried piston!

I would say it oil starved for sure.

2 stroke oil syringe is the way to go. you can get one at menard's, or your favorite, fleet farm. I have one that I use to make the premix for my snowblower.

Further, I also have a seperate gas can that is labeled "two stroke" on it to avoid any mishaps

yaitisme · 10/27/2007, 07:01 PM

Too lean (piston top) and the seizure mark is from not allowing the piston and the cylinder to fully heat up before going to full throttle or loss of lubrication.

10/25/2007, 09:55 PM	#1
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	OT - Need help quick, engine rebuild question. I am re building the $%^##@ leaf blower, and recv'd the parts tonight. I have it all the way apart, and am replacing the piston thingy, and the piston chute thingy (thing the piston goes up and down in...) I can normally replace old parts with new parts, but there were directions in the new piston parts that have me confused. It reads: be sure to heat the new piston too 150 degrees F. and to clean the rust inhibator from the piston with alcohol or solvent. I scrubbed the piston down with alcohol and a solvent, nothing really came off... but why should I heat the piston up, that will make it larger, and not fit into the other part I bought, the chute? do I really need to heat it up? If anyone could nudge me, I'd like to get it back up and running tonight, it would save me an hour or two tomorrow... Jason

10/25/2007, 10:01 PM	#2
Limpit Happy Reefer Join Date: Nov 2004 Location: "Home of the nations fastest high banked 1/4 mile" Posts: 1,563	J, Heating it up would expand it if anything but not much at 150. I am thinking that they may have you do that to bake out any inhibitor you missed. It could also be to heat treat the piston for some reason but again 150 is not much. Just stick it in your oven to be on the safe side. I am not really much of a 2 cycle mech. so maybe that is what it is all about. BTW, the "chute thingy is called a cylinder.

10/25/2007, 10:03 PM	#3
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	I could hit it with the torch for, oh, say, a whole 25 seconds, but it's smaller than 1/2 a "C" battery. I'll do it, but I was kinda wondering why...

10/25/2007, 10:05 PM	#4
Limpit Happy Reefer Join Date: Nov 2004 Location: "Home of the nations fastest high banked 1/4 mile" Posts: 1,563	Just stick it in your oven. I would not hit it with a torch, you cannot regulate the temp. that way.

10/25/2007, 10:07 PM	#5
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	I spose... I already had it on... I'll do that.... Thanks

10/25/2007, 10:15 PM	#6
Limpit Happy Reefer Join Date: Nov 2004 Location: "Home of the nations fastest high banked 1/4 mile" Posts: 1,563	Hey wait..I just thought of a great idea. Put it in the microwave, it will cook faster.

10/25/2007, 10:19 PM	#7
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728

10/25/2007, 11:57 PM	#8
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	Does anyone have a fool proof way of adding exactly the right amount of oil for their 2 cycle engines? I had alot of time to think while I tore this apart, tried to fix it, put it together, - did not work, ordered the parts and repeated the process... and the only explanation I can come up with is that I do not remember if the oil in the 4oz container was completely full or not. I usually add a little less than the full amount, as 40:1 is 3.2 oz to 1 gallon. this way I err on the heavy amount, but maybe I should get a measuring container or something... do they make such a beast that is intended for this type of application? BTW it runs again. in case anyone doubted me Scott. J Thanks Limpit, I had just enough time to crack a Root beer while the piston was in the oven.

10/26/2007, 12:09 AM	#9
Fishcrazy06 Registered Member Join Date: Sep 2006 Posts: 1,568	I dont know if this is a good thing or not but I was always told my a number of different 'old timers' its better to add a little extra oil than a little less. I have always done that. Like I said dunno if its good or bad but I have never had a problem doing it this way. Eric

10/26/2007, 12:17 AM	#10
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	Ironically, I to was told that by an old timer... I think looking back the 4oz of oil may have been 3, but it's hard to tell as that was 2 weeks ago...

10/26/2007, 05:46 AM	#11
bigreef74 Registered Member Join Date: Nov 2006 Location: wisconsin Posts: 334	Ok here is my thought on 2 cycle oil and octane rating on fuel. First all 2 stroke oil is different, each manufacture use different additives to their oil. This is because each oil is maid for a specific brand of small engine and the make up of their internal engine parts pistons, cylinder wall sleeve. â€œchuteâ€ Next part. Heating the piston expands it to release the sealants. If you were to look at a piston under a microscope it would look like the rock mountains. 87 octane verses 93 octane I use 93 octane in all my lawn equipment, because the 93 octane has more lubricants and less impurities. In my vehicles I use 3 tanks of 87 and the fourth it 93 octane to help clean out the carbon and the also lubricate the vale train. On another note make sure you install the piton rings correctly. Always use break clean to remove sealants and grease from parts break clean is the most cost effective metal cleaner that dose not leave a residue. Hope this helps. Mike

10/26/2007, 07:36 AM	#12
yaitisme Moved On Join Date: Aug 2006 Location: North East Wisconsin Posts: 1,216	I'm not sure that there are more lubricants or less impurities in 93 octane... there is more octane though. I use premium, from stations that don't add Alcohol, in my small engines also. The octane number drops over time so 87 octane is only going to get lower, not good. I also avoid the alcohol because it tends to absorb water over time. In modern cars, 10% alcohol is no big deal and higher octane is just a marketing ploy unless it is needed by an engine with higher compression (common on Nisson's). As far as heating the piston, Mikes answer sounds right. Must be a reason the Man. wants you to do it, so why not? 2 cycle oils measurement.... for that some of an amount, I use a 2 cycle oil seringe (my spell check can't even help me here). I actually use a turkey injection seringe for the 100 to 1 full synthetic oil I use (@ 1.3 oz to a gallon all though I use an even 2 oz). Your problem is more than likely on the carb side. If the piston moves a 2 cycle engine will typically run. If the carb. is slightly off or the reeds are damaged your screwed. I agree with Mike on 2-cycle oil too, not all will burn right in all engines. I used to buy what ever was on sale, but stopped doing this after have mixed (pun intended) results. When I got into snowmobiling, I did a ton of reading on 2-cycle oils and now only use two types... Mercury Premium in my outboard and Amsoil 100-1 (Amsoil 2-cycle injection oil in the sled until it stopped snowing LOL) in everything else. No more problems and the 100-1 is easier on the environment. I wouldn't mix up any new 2-cycle oil this late in the season unless you have something to use it in over the winter. If your in the area, stop by any fill your blower up with some of my gas. I use it through out the year so it stays relatively fresh. I could also get you a couple oz. of 100-1 to try it yourself.

10/26/2007, 09:52 PM	#13
jmkarcz Registered Member Join Date: Feb 2003 Posts: 2,728	I did go buy a bottle of 2-cycle oil from/with some well known label on it, like Briggs and Straton... I really was just sucked in by the handy pre measure cup on the top... You know, the ones that you release the cap, and as you squeeze, the oil/fluid flows up along the side thru a tube and fills the cup to the level you squeeze to... when it's empty, I'm gonna just get some other economy size 2 cycle oil with a brand name and refill it... it'll be a pain, but I like the thought of knowing that I DID get the 3.2 oz in the gallon (and maybe a bit more and how much more.) Here's what I ended up fixing... because I believe the oil was a bit to lean... it ran for 45 minutes just fine... it's the only explanation.

10/27/2007, 04:15 PM	#14
kiowascout Registered Member Join Date: Apr 2005 Location: Depere, WI Posts: 467	that is one fried piston! I would say it oil starved for sure. 2 stroke oil syringe is the way to go. you can get one at menard's, or your favorite, fleet farm. I have one that I use to make the premix for my snowblower. Further, I also have a seperate gas can that is labeled "two stroke" on it to avoid any mishaps

10/27/2007, 07:01 PM	#15
yaitisme Moved On Join Date: Aug 2006 Location: North East Wisconsin Posts: 1,216	Too lean (piston top) and the seizure mark is from not allowing the piston and the cylinder to fully heat up before going to full throttle or loss of lubrication.