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General Forestry => Chainsaws => Topic started by: nhlogga on June 17, 2009, 08:27:59 PM

Title: rod bearing problems 372/2171
Post by: nhlogga on June 17, 2009, 08:27:59 PM
question. every husky 372 / jred 2171 i have owned lasts me about 1 year to 1 1/2 years of steady running. problem is the rod bearing disentigrates. i've talked to my local saw dealers and can't get a straight answer. i've been told that husky did have a bad run on cranks years back. been told to let off my heave trigger finger(done that). been told to keep saw sharp{duh! everyone knows that). one dealer told me to use the quakerstate mix he sells and mix it 32:1. tried that on a brand new saw from day 1 and it didn't last a year. i mix my gas with jred oil(5gal. bottle) to 4 1/5 - 5 gal of high octane gas. it doesn't matter if i use stihl or husky mix either. i bring my saws to my dealer every so often and have him put it on the tach so they aren't over revving. i keep up with maintenence on them. i clean the air filters usually a couple times a week which is all that is required on huskys/jreds. i know alot of guys that get years out of their saws. i don't spray my air cleaners off with starting fluid like alot of guys i know do. i usually rinse them in mixed gas then blow them off with compressed air. any ideas? i have plenty of saws with bad cranks and good p/c's and everything else to go with them.
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Title: Re: rod bearing problems 372/2171
Post by: Maineloggerkid on June 17, 2009, 09:06:17 PM
I have never heard tell of that problem. I have run them relentlessly in hardwood with no ill effects. The oldest one I had is now 8 years old and still going, although in someone elses hands. I have a new 385Xp, and it seems really tough, too. A little more weight to lug, but it seems to stand up. Maybe try a 385/2186 and see if it last longer.
Title: Re: rod bearing problems 372/2171
Post by: chucker on June 17, 2009, 09:33:26 PM
 bottom line!! ITS ALL IN THE OIL, never had a problem internaly with either brand of saws with a oil mix of 24:1 for long hard days of cutting w. oak and red. the 625 has had 1 new ring (original guts) and it is a 1986 model . the 670 is due for a new ring someday as i can feel the loss of power from 20 years of cutting!! so if 24:1 is to rich go with a electric saw maybe??
Title: Re: rod bearing problems 372/2171
Post by: joe_indi on June 18, 2009, 08:01:52 AM
Check the ignition module .Is it black or blue in color?
When I was retailing huskys a couple of years, I had seen the crank big end failures in 372xps.
This used to happen  on saws with blue ignition modules.
They had speed limiters in them, while as the older black modules were without speed limiters.
What I think happens is this, at a certain rpm the speed limiter starts cutting off the ignition current, so that in every alternate combustion stroke there is no combustion.The engine sounds as if its 4 stroking with a rich carburator setting.
For the crankshaft under cutting load, this must be like tripping over it's own feet for every other step taken.
The damaged bearing must be the husky 372's equivalent of badly bruised knees.
Joe
Title: Re: rod bearing problems 372/2171
Post by: olyman on June 18, 2009, 08:03:17 AM
wonder if maybe the flywheel, or clutch side seal is bad, thinning out the fuel mix at rpm's????
Title: Re: rod bearing problems 372/2171
Post by: Rocky_J on June 18, 2009, 04:08:16 PM
Olyman, I suspect Joe is correct. The rev limited ignition module would tend to fool people into thinking their saw was running rich when in fact it was running lean. Stupid pencil pushers making decisions to 'protect' users end up costing us money instead.  :(
Title: Re: rod bearing problems 372/2171
Post by: Cut4fun on June 18, 2009, 05:28:12 PM
You guys could be on to something with the blue coils.

I have a 365 special that is like new and I had to trim the rev limiters on H and L to get it to operate off of the rev limited coil.  From the factory the best adjustment you could do with the limiters on was right on the rev limiter and it sounded rich till I  put a tach on it and you could see it jumping around on rpm's and I looked and seen that blue coil.

Runs pretty darn good for a stock saw. Even ran it at the GTG and it got in the middle of the pack and I think it was the fastest stock 4 cube in the class.



Title: Re: rod bearing problems 372/2171
Post by: ladylake on June 18, 2009, 05:37:00 PM
 Other tha oil and running way to lean,( I can't imagine anyone running up against a rev limiter a lot when you should be running 9 to 10 thousand in the cut, rev limiter set at around 13 thousand or so although it could cause trouble tuning) maybe running the chain way tight. I know on a truck if you run the belts real tight it causes bearing to go out, waterpump, alternator etc.   Steve
Title: Re: rod bearing problems 372/2171
Post by: Cut4fun on June 18, 2009, 07:24:55 PM
Here is the Husky tool for splitting the crankcases (if you are having trouble) to put the new cranks in.   


http://cgi.ebay.com/502516101-CRANKCASE-SPLITTER-TOOL-HUSQVARNA-CHAINSAW_W0QQitemZ390033250650QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5acfcb195a&_trksid=p3286.m20.l1116
Title: Re: rod bearing problems 372/2171
Post by: Al_Smith on June 18, 2009, 08:17:16 PM
I can't honestly say I've ever seen a rod bearing failure on a saw engine .I've seen a few main bearing failures but they were caused by dust ingestion caused by faulty air filters .
Title: Re: rod bearing problems 372/2171
Post by: sablatnic on June 19, 2009, 12:43:33 AM
Husqvarna , Partner and Jonsereds had some rod bearing problems about 25 years ago, but I haven't seen any failed bearings lately.
Title: Re: rod bearing problems 372/2171
Post by: Cut4fun on June 19, 2009, 10:55:31 AM
Quote from: ladylake on June 18, 2009, 05:37:00 PM
Other tha oil and running way to lean,( I can't imagine anyone running up against a rev limiter a lot when you should be running 9 to 10 thousand in the cut,

I think what they were getting at, if the person tuning the saw  thought they were rich by hearing the saw  hitting the rev limiter and thinking it was 4 stroking and kept leaning it out. Then they ended up super lean in extended cuts. Just a WAG = wild a$$ guess. Could be wrong, but thats what I got out of it.
Title: Re: rod bearing problems 372/2171
Post by: ladylake on June 19, 2009, 12:41:12 PM
Quote from: Cut4fun on June 19, 2009, 10:55:31 AM
Quote from: ladylake on June 18, 2009, 05:37:00 PM
Other tha oil and running way to lean,( I can't imagine anyone running up against a rev limiter a lot when you should be running 9 to 10 thousand in the cut,

I think what they were getting at, if the person tuning the saw  thought they were rich by hearing the saw  hitting the rev limiter and thinking it was 4 stroking and kept leaning it out. Then they ended up super lean in extended cuts. Just a WAG = wild a$$ guess. Could be wrong, but thats what I got out of it.

  Hey now your getting like the news media just putting parts of what I said in your quote, I believe I mentioned tuning. If I read Joe's reply he said hitting the rev limiter under cutting load.  Getting it tuned to lean with a rev limiter would be real easy.     Steve
Title: Re: rod bearing problems 372/2171
Post by: joe_indi on June 19, 2009, 01:24:36 PM
Quote from: ladylake on June 19, 2009, 12:41:12 PM

  Hey now your getting like the news media just putting parts of what I said in your quote, I believe I mentioned tuning. If I read Joe's reply he said hitting the rev limiter under cutting load.  Getting it tuned to lean with a rev limiter would be real easy
Steve, sorry I have to use the above as a quote.
Under cutting load is what I said, and what I had meant.
If the saw was hitting maximum rpm off load with the speed limiter working, the crankshaft big end would not be under any force that could  damage it.That is, unless you wanted to wreck the saw and prolonged the full throttle for a very long time without load.
In the cut, the saw does not always run at 9000 or 10000 rpm, momentarily the rpm could move up to 13000+.
When the speed limiter starts doing the equivalent of throwing bolos at the crankshaft, with the saw under the partial load of the cut, the chain would de-accelerate quite a bit, causing the crankshaft also to do the same.
I once saw a Stihl video which was taken of a saw chain with filed off depth gauges .
At a relative slow motion, you could actually see the impacts being transferred to the crankshaft.
The resultant forces on the crankshaft due to the speed limiter coming into play, is somewhat similar.
That is what I think.
At least after seeing numerous husky crankshafts.
Changing the ignition module to the older black ones prevented a repeat performance, in most cases.The exceptions were the saws that used to be revved at maximum speed for nearly 5 minutes before and after work.This was a practice picked up by some saw owners because they had seen truck drivers do this.But with trucks it was for a different purpose altogether. 

Post Script 30 minutes later.
The crankshaft failure was higher with saws used for continuous  limbing .
Title: Re: rod bearing problems 372/2171
Post by: ladylake on June 19, 2009, 03:56:12 PM
 Joe  Nothing wrong with using quotes just use the whole quote.  What you said makes sence as a lot of operators over rev their saws. Let them scream while not cutting much.  Or it could be adjusted too lean, or you hit on another thing, rakers way to low. Steve
Title: Re: rod bearing problems 372/2171
Post by: chucker on June 19, 2009, 04:59:28 PM
or just no sense of the use of the tool or its given instructions??  when a saw is reved to the maxx with all that power its got to give sooner or later. like full power scotty and hit the chain break!!! lol
Title: Re: rod bearing problems 372/2171
Post by: nhlogga on June 20, 2009, 06:22:04 PM
i was thinking that all the limbing i was doing could have been part of the problem. also i was cutting a lot of underbrush and "finger wood" on houselots. i was working as a sub whose mentality was go!,go!,go!. as long as the saw was cutting it didn't need to be sharpend. WRONG!!! I tried to explain to him that running a saw that was not properly sharpened was just a blown up saw ready to happen. He didn't care. $700+ for a new saw didn't mean anything to him. It wasn't his saw blowin up. After almost 5 years of working for him I got a better offer and parted ways. Now I just show up with my lunch box. No more go!go!go!. On top of that, he hated high stumps so as the ground got pounded down around the stumps from the skidders and other equipment I'd be told to cut the stumps down. A chainsaw is not a stump grinder. Granted he was a good guy and taught me alot and paid well but at what cost when I was spending money on a few saws a year and all the beat up chains I wasted? Great tax right-offs but I would have liked to put some of that $$$ in my pocket. Would have left sooner but in this economy you gotta job you keep it.
Title: Re: rod bearing problems 372/2171
Post by: ladylake on June 20, 2009, 10:52:36 PM
 Joe   Sounds like you were right, a lot of running up against the rev limiter due to no load from dull chains.   Steve
Title: Re: rod bearing problems 372/2171
Post by: Dave Shepard on June 21, 2009, 08:03:31 AM
FWIW, that case puller is available from your local Husky dealer for about $60-65, and no shipping. ;) That'll save you $30 :)
Title: Re: rod bearing problems 372/2171
Post by: nhlogga on June 29, 2009, 06:13:39 PM
Thanks for all the help and advice. So the black non limited coils are better for the saws?
Title: Re: rod bearing problems 372/2171
Post by: joe_indi on July 01, 2009, 01:21:14 AM
Quote from: nhlogga on June 29, 2009, 06:13:39 PM
So the black non limited coils are better for the saws?
The answer would be 'Yes' as well as 'No'.
It depends more on the user.
A person who knows his saw inside out might find the coils without speed limiters a better option, because he would know how and when to tune his saw.
But an average or new user is better off with the coil with a speed limiter, provided he avoids experimenting with the carb settings.
Huskys are sold in most countries as 'EPA' versions, which could also  be read as lean burn with limited adjustments.
Asian markets still get the non-EPA versions.

Joe