Excessive Heat Milling with a husky 288xp?

[ridgerunner97]

Anyone have any experience milling with a husky 288xp lite, I am new to chainsaw milling as are my friends and we were doing a 16in diameter 7ft long cherry the other night when my saw started to smoke out of the flywheel cover slots. Only third cut and let saw cool for 20min between cuts. Haven't had the problem before. I stopped pulled the top cover off the saw and there was no chips or anything inside although it looked like the cover over the muffler was starting to turn black like it was burning. No deforming though. Any tips to modify the top plastic cover over the muffler to reflect heat, or general tips would be greatly appreciated. Im trying to not destroy my equipment and maximize my efforts. Thanks

 

[Can8ianTimber]

From what I have learned a sharp chain is the most important thing. Listen to your saw. I just burned up my Husqvarna 3120 and I am learning the hard way what not to do.

Good luck

 

[ridgerunner97]

yeah i touched the chain up after the second cut, so i ruled that out, my filter was brand new and the fuel was mixed perfectly and im running 93 octane sunoco fuel it was fresh so i counted that out, and i wasnt forcing the saw so i don't know what she was doing but it was cutting fast as hell we were doing 2ft a minute which from what ive read is damn fast in hardwood. It is just normal chisel chain too. Im very sorry to hear about your beast taking a dump. I picked my 288 up for a lil over 300 bucks so there are some more sweethearts out there im on the prowl for an older husky 2100 or 3120xp to mill with. Thanks for the insight, im new to the site and am agog in all the knowledge floating around here.

 

[Crofter]

Set the HS jet about 1/4 turn richer than what you would use for bucking. Should be strongly 4 stroking till you put it under load. That will help keep head temperatures down.

 

[redprospector]

I don't know much about CS milling, but I did burn up a 288xp milling once. I think the saw was about to go anyway though.

Without looking at the saw, about all I can say is; Where there's smoke, there's heat. Where there's heat, there's friction (at least on a saw).
Something ain't right under that cover, pull it and take a look.

Andy

Crofter may be right, could be lean, getting warm, and burning crud.

 

[ridgerunner97]

Hey i will give that a shot, i was thinking about tinkering with sum kind of minimally invasive heat shielding under the top cover where it overlaps the muffler. Also would chaging the muffler over to a type that has a larger exhaust pipe exit in the stock location decrease temperatures? Its hard to describe but Baileys has one try this link, http://www.baileysonline.com/itemdetail.asp?item=QH+50359+1501&catID= It differs from my stock muffler as in this one has a large pipe where my stock one is just a tiny rectangle in that location.

 

[howellhandmade]

Your theory is that the muffler is heating up enough to make the plastic smoke? Even if a heat shield were to protect the plastic, that's kind of like treating an arterial cut by mopping the floor. That much heat shouldn't exist in normal operation, so either the saw is running too lean, is under too much load, the clutch is slipping, or something else.

Jack

 

[Can8ianTimber]

My 3120 burning up was just stupidity. I hit steel and kept pushing it with a 60" bar fully burried in white oak. I was trying to split the log so I could get it on the mill. Anyways Walker is rebuilding it and "walkerizing" it so it should run cooler and with more power than it did before.

So a guy at work had a thought about somehow mounting a thermostat to the saw so you could see if it was overheating. Could you tap between two fins and thread it in so that the tip touched the body of the cylinder from the outside? Larger motors have thermostats, why not a large saw for milling? It would be a lot more complicated than that I am sure and you would have to have the right unit but what do you guys think about the consept???

 

[Brushwacker]

If your muffler comes loose the exhaust escaping can cause heat to your engine + I believe it would run leaner. My friends Husky 385 seized up like that about a year ago. If you haven't, check your muffler screws and gasket.

 

[woodsrunner]

Maybe running too lean

Set the HS jet about 1/4 turn richer than what you would use for bucking. Should be strongly 4 stroking till you put it under load. That will help keep head temperatures down.

:agree2:

Be sure your saw isn't running lean! As others have said there are several things that could possibly cause a lean condition. If you don't understand what that really means (no offense intended) use the search function and learn as much as possible about it. Milling is extreme duty for a saw and there's no point in burning up a good saw when it might be avoided by some simple maintainance or adjustment. Good luck, milling is fun (until you fry your saw).

Scott

 

[howellhandmade]

SNIP

So a guy at work had a thought about somehow mounting a thermostat to the saw so you could see if it was overheating. Could you tap between two fins and thread it in so that the tip touched the body of the cylinder from the outside? Larger motors have thermostats, why not a large saw for milling? It would be a lot more complicated than that I am sure and you would have to have the right unit but what do you guys think about the consept???

You could just shoot an IR thermometer at the cylinder. Might take another set of hands, but comparing "regular" temp readings with milling might be informative. Can't really compare to big motors, which read the temp of coolant, which a saw doesn't have of course. Although you could maybe adapt an EGT sensor tapped into the muffler close to the port. Or you could put in a thermocouple like you suggest, but to explore the concept I'd start with the handheld IR unit, they're cheap and useful for lots of stuff.

Jack

 

[LAndrews]

Most of the time smoke is just oil vaporizing because it's heated to where it does. If oil's been building up for a while, getting the saw good and hot for the first time will do it.

There shouldn't be a direct correlation between fuel/oil/air mixture and smoke coming out of the flywheel cover - unless the left side seal is gone and the thing shouldn't run too well if that's the case. Load alone can get the saw very nearly as hot as a lean (or way too rich) mixture. +1 for the IR meter advice - they're worth their weight in gold when it comes to diagnosing problems.

I washed down my 395xp with about four cans of brake cleaner shortly after I got it. Tons of oily sawdust flowed out of every orifice, and the saw ran noticeably cooler afterwards. Having said that, enough paint came off that I can't recommend that approach. Never had a problem with kart engines... <shrug>

 

[BobL]

You could just shoot an IR thermometer at the cylinder. Might take another set of hands, but comparing "regular" temp readings with milling might be informative. Can't really compare to big motors, which read the temp of coolant, which a saw doesn't have of course. Although you could maybe adapt an EGT sensor tapped into the muffler close to the port. Or you could put in a thermocouple like you suggest, but to explore the concept I'd start with the handheld IR unit, they're cheap and useful for lots of stuff.

Jack

IR's will not be accurate even when the cylinders are clean, then you will have way too much variability caused by soot, oil and sawdust to contend with.

I have tried with both IR spot meters and FLIR cameras to monitor temps and neither agreed with a thermocouple temp reading.

Here is an IR image of the BIL Mill with 880 taken with a FLIR camera. The saw had not even been started and the ambient temp - as was saw - was 24ºC (ie red in the image). IR readings of shiny stuff (Mill, exhaust and clutch cover) are too variable (from white to black!).

 

[wavefreak]

:agree2:

Be sure your saw isn't running lean! As others have said there are several things that could possibly cause a lean condition. If you don't understand what that really means (no offense intended) use the search function and learn as much as possible about it. Milling is extreme duty for a saw and there's no point in burning up a good saw when it might be avoided by some simple maintainance or adjustment. Good luck, milling is fun (until you fry your saw).

Scott

How can you tell if it's running lean? An oxygen sensor isn't too practical . I mix my gas 40:1 instead of the 50:1 the manual says. Some here say to mix it even richer.

 

[howellhandmade]

How can you tell if it's running lean? An oxygen sensor isn't too practical . I mix my gas 40:1 instead of the 50:1 the manual says. Some here say to mix it even richer.

Richness refers to the ratio of air to fuel, not oil to fuel. It's common to confuse lean/rich with lubrication, but they are separate issues. Fuel in excess of what can be burned (richness) takes heat out of the system by changing from liquid to vapor, then carrying the heat out the exhaust. Oil helps the bearing/sliding surfaces slip and helps keep temps lower by reducing friction, but does not remove heat through vaporization as effectively as gasoline. So it is possible for a 2-stroke engine to be well-lubricated but still overheat. In fact, more oil in the mix reduces the amount of fuel available to the existing quantity of air, making the fuel delivery at a given setting more lean. So, you can lean out your engine no matter how much oil you have with an air leak or bad carb setting, and you can cook your engine with straight gas no matter how rich the carb is set. Here's the commonly referenced link for carb settings:

http://www.madsens1.com/saw carb tune.htm

Jack

 

[ridgerunner97]

Okay guys awesome insight into my problem, i talked to my local S***l dealer mechanic, who is a friend and happens to respect the husky saws, whole different story and lets not get off topic, but he said to give the hi needle a little adjustment and it will cool the saw. Also to the other posters about clean fins and thermocouples etc. etc. good ideas, however the saw is extremely clean, well maintained and highly tuned. Im young, and new at milling but am no rookie with a saw lol. Thanks to everyone for being so helpful and especially respectful about answering my questions.

 

[Crofter]

Ridgerunner, the part of your post about "highly tuned" very often raises a flag because in a lot of peoples minds, that equates with "really screaming" etc., What it often means is that the saw (or other 2 stroke) is set dangerously lean and about the worst condition to have for milling. I am sure your friend mentioning a little bit of adjustment on the HI referred definitely to counter clockwise and richer! Good advice but often disregarded. Kills more two strokes than running straight gas does.

 

[woodsrunner]

Richness refers to the ratio of air to fuel, not oil to fuel. It's common to confuse lean/rich with lubrication, but they are separate issues. Fuel in excess of what can be burned (richness) takes heat out of the system by changing from liquid to vapor, then carrying the heat out the exhaust. Oil helps the bearing/sliding surfaces slip and helps keep temps lower by reducing friction, but does not remove heat through vaporization as effectively as gasoline. So it is possible for a 2-stroke engine to be well-lubricated but still overheat. In fact, more oil in the mix reduces the amount of fuel available to the existing quantity of air, making the fuel delivery at a given setting more lean. So, you can lean out your engine no matter how much oil you have with an air leak or bad carb setting, and you can cook your engine with straight gas no matter how rich the carb is set. Here's the commonly referenced link for carb settings:

http://www.madsens1.com/saw carb tune.htm

Jack

Well Said!!

Scott

 

[LAndrews]

Richness refers to the ratio of air to fuel, not oil to fuel. It's common to confuse lean/rich with lubrication, but they are separate issues. Fuel in excess of what can be burned (richness) takes heat out of the system by changing from liquid to vapor, then carrying the heat out the exhaust.

One tiny addendum: Richness is good until the exhaust has enough fuel in it that it's basically a blowtorch. First time you see a glowing-red muffler - there you are. More common problem with an expansion chamber than a can exhaust...

BobL: Very, very sweet IR camera setup. Me likes. Here's another fun setup - nothing quite like >1000FPS.

www.nacinc.com

 

[SilverBox]

yup, others have said richen it up, I agree. A few days ago, I ran a used (but new to me) 394 xp for a few cuts and it got fairly hot (it cut real nice thu, lol, when its lean it cuts like heck, but burns out fast), but I could tell by the sound it was running a bit on the lean side, before I run it anymore milling, I'll probably go 1/4 turn out on the H screw to fatter 'er up a little.