Comparison

Al Smith

Mac Daddy
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Mar 6, 2005
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Northern Ohio
This is a few pictures showing a saw ran first with a factory muffler but ran on 32 to 1 oil and secondly after a gutted and improved muffler .

The first pic was taken about a year ago .I lifted the top and did a real simple port job .Just widened the exhaust polished the intake type .At that time I gutted the muffler and added the second port. Much like a factory duel port . Prior to that there was a slight build up of carbon ,not bad though .

The second pic was taken Saturday .The piston was not touched .It is just as it appeared when I lifted the top .That saw has had approx 30 to 40 running hours since a year ago .It wasn't ran tank after tank though .15-20 minutes per time cutting stuff out of a pile to splitable lengths .Almost no carbon .That piston had a nice slick coating of oil when I lifted it .

That cylinder is going to be reworked to raise the comp for some improvement in performance .I thought it noteworthy to post just to show what improving the exhaust flow does for an engine .Draw you own conclusion on the oil .
 

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Noticeable difference in deposits on that piston. Very interesting.

Looks like your shop could use a port job as well. Kind of looks like my desk top. But I know where everything is.
 
I have yet to pull apart an engine, stock or modified, and find a piston so free of carbon, though I have noted improvement with a larger exhaust port and muffler opening. What type of oil are you using, Al? Were you also using 32:1 after modifying?
 
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I'm a slob every where but in the house where in I'm a perfectly tidy guy .:lol:

The oil was just whatever ever TSC sells ,nothing special .I've ran 32 to 1 all my life except maybe as a kid with those real old saws which were 16 to 1 .

Prior to the original half fast port job that saw ran with the baffles but minus the screen with just the standard 038 AV single hole muffler . After which as I said that muffler was nothing but the shell .No baffle ,screen ,nothing but the can .

It got a tad loud but not really that bad .Then again I grew up on reed engined Macs so any thing is quieter than them .

Seldom once I work on a top end do I ever get back into the saw .This one was perhaps the first .Maybe they all look like that but somehow I doubt it .
 
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No that's an AV .I haven't checked the mag .I will say this for the mag ,that little pup outcut both a 2100 Husky plus an 066 Stihl the last I ran it for time in 10 by 10's . Actually the Rocky special is about my favorite saw .:thumbup:
 
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This is the Mag piston after I cut a pop in it .It really wasn't too carboned up before I tore into it either .

The differences in the saw engines as designed are slight but distict .The AV uses a hemi domed piston with a offset combustion chamber .The mag uses a flat top piston with a centered chamber . Why the difference I haven't a clue .
 

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I've ran 32 to 1 all my life except maybe as a kid with those real old saws which were 16 to 1 .

Why Al? Not being mean, but I am pulling down saws at 50:1 that are as well, or better oiled than that one.
Keep in mind I am an "oil snob" and run NOTHING but premium gas and Royal Purple at 50:1.
 
Why Al? Not being mean, but I am pulling down saws at 50:1 that are as well, or better oiled than that one.
Keep in mind I am an "oil snob" and run NOTHING but premium gas and Royal Purple at 50:1.

The post is unclear. Are you equating "better oiled," with carbon on the piston crown? That's not a valid conclusion. Generally, modded saws need a larger amount of oil in the mix, like 32:1. That is one school of thought anyway.

I run 32:1 in all my modded saws. The plug looks happy.
 
Royal purple :O

Ha Ha Ha ,you've got to be pulling my leg .:lol: That company was started by PT Barnum or his long lost cousin .

NOPE!!! I SWEAR by the stuff!! Ran it in my last truck, gained 2 MPG. Started using it in my saws, everytime I tear them down they are "slick and slimey".
I switched my new truck over to Mobil 1, 16MPG. I have since gone to Royal Purple, 17.5 MPG.
Who is selling what?
 
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Okay ,Purple it is .If it feels good do it .I just change the stuff on a regular bassis myself .

I'll tell you something odd though .Most people including myself are old school with 10W 30 oil ,the old standby .Newer engines are designed to run on 5W 20 because of tighter tolerances and they get better gas mileage if that weight is used. Hard to believe but true .

Then again if they get a couple hundred thousand miles on them 90 weight gear lube might be called for in some cases .Some get a tad loosey goosey .
 
I hear and agree with that Al! I got called the first time I had the oil changed in my old truck, '97 F150 and wanted 10W-40. They all but came unglued!!
The "new" truck '04, takes the 5W-20 you mention. The "old" truck took MANY years of abuse, puled things it shouldn't have and dealt with me on top of all of that! 4.2L, I did head gaskets at around 80k, and it finally started knocking at 146K. This was after years of Royal Purple mind you. Engine was clean as clean. Thebearing wasn't even loose, it was worn and showed more wear on the bckside of the bearing!
Now this is the TRUCK that though it was a sports car, seriously!! Anybody but me got in it and drove it the check engine light would come on because they wouldn't push it like I would. Then it ran like crap until you pulled off a battery cable. It was indeed an oddity!!
But after pulling off the pan and valve covers and seeing how clean they were, on top of the gas milleage increase, I am SOLD!!!
 
You cannot run 10w-30 or 10w-40 oil in the Triton motors because the oil passageways in the heads are too small. The oil will pool up in the top of the motor and the bottom end will starve. 5w-20 in my 5.4 with 99,800 miles on it right now and it runs perfect, without disconnecting any wires or running it hard to keep the check engine light from coming on. :roll:

And I'm a cheapskate, I run the NAPA house brand 5w-20 because it's dirt cheap. :lol:
 
That's residue .I never drink Pepsi unless it has a nip of Black Velvet in it .;)

There is a car guy on the radio here that rates how long it takes to do a DIY car repair by the number of beers you would drink while doing it. Yeah that's a 2 beer job, no problem.
 
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What will surprise most people is a tractor engine .Huge radiator and well limited by the governor as to rpm and small carbs .They seldom get gunky inside .

The worst thing for an engine is short jaunts that don't get it up to operating temps .You actually wear the damned things out by starting and stopping them .

Take an outboard motor.Cooled by an entire lake or the Atlantic ocean .Barring any other problems they never overheat and run forever .

Saws get cooked by restrictive mufflers and fins packed full of sawdust . Some will run almost forever .I've got a shed full of living proof .:|:
 
My 5.4 is happy no matter how I drive Brian, it was an oddity with the 4.2 for sure! My wife would drive it and "short shift" it and it took weeks to get it to run right without the light comming on!:? It was never "right" from the day I bought it, but it liked the way I drove it so all was well:D
When fuel prices shoot up again, and they will, try a good synthetic, your MPG will go up more than you imagined! 1.6MPG doesn't sound like much, but figure that over a 24 gallon tank!
 
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Things have changed regarding automotive type engines .It used to be about standard 2.5 to 3 thou clearance on rod and main bearings .Now days that is closer to 1 thou .You cannot pump 30WT oil through that tight of a fit .

The good news is these modern designs if taken care of will likely go an easy 200 thousand miles . Ya gotta change the oil though .
 
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