Stihl MS500i Hot Start Problem

[L34]

Ok.
Seen plenty of topics on this and the "other" forum about poor performance when using high octane fuel in non high worked over saws.
I can under stand in a high comp V8.

 

[Clyde85]

I am not sure if there's any truth to this or not, but I was told years ago that adding two cycle oil to the gas reduces the octane level of the fuel.

 

[TimberMcPherson]

I have done 2 summers now with our 500i and its never had the slightest issue

 

[juanroberts]

 

[Long Bar 60]

I'm a timber faller cutting salvage on one of the giant CA fires from last summer. Bought a 500i because that was the only larger CC saw available. I've had A LOT (over 50) of big Stihl saws in my career and I've never had one that barely starts and runs terrible when it's hot. The saw was unusable and had to pack out of the hole to get another saw. Dealer said I needed a "green weenie" (foam) air filter. None of the dealers that I've talked to seem to know anything about these saws. Terribly disappointed spending over $1500 for a saw that I can't depend on.

 

[juanroberts]

Sorry to hear it was a disappointment. One of the reasons I got the ms500i was that it was reportedly long-term maintenance-free. In particular: “The thing has just kept on going, without any problems. The air filter is basically completely clogged.” This is from:
https://www.forestry.com/editorial/equipments/result-long-term-testing-stihl-ms-500i/
When I bought mine the dealer recommended using non-ethanol gas. I know my smaller saw boils its gas when it gets hot but it seems to not mind it. I have not run the ms500i as hard yet. Maybe in a couple of months.

Having a fuel injected dirtbike, I doubt its the air filter.

If you figure out, please let us know.

Thanks.

 

[stihlaficionado]

In addition to not needing a 500i, nor having the money to buy a 500i, it is to new a saw to spend that kind of money. My 461 is going like new after 5 years, and I expect to get another great 5+ years out of it. My ms290 which I use more then anything is now on its 10th year and it too is also running and starting great. Compression test last year tells me that it is very healthy also. I did a carb rebuild to address some rare bogging issues -- 20 minutes of work, $6+ in cost and it is perfect.

500i? Why?

Cuz it's the first truly innovative saw in quite awhile
Resale value should be high if kept in good condition

 

[lone wolf]

View attachment 912144
Cuz it's the first truly innovative saw in quite awhile
Resale value should be high if kept in good condition

Maybe the injector will hold up better to Ethanol.

 

[Long Bar 60]

I'm a timber faller cutting salvage on one of the giant CAView attachment 912059 fires from last summer. Bought a 500i because that was the only larger CC saw available. I've had A LOT (over 50) of big Stihl saws in my career and I've never had one that barely starts and runs terrible when it's hot. The saw was unusable and had to pack out of the hole to get another saw. Dealer said I needed a "green weenie" (foam) air filter. None of the dealers that I've talked to seem to know anything about these saws. Terribly disappointed spending over $1500 for a saw that I can't depend on.

So I put a "green weenie" on the 500i and HOLY COW (!!!) what a difference. The stock air filter must have been totally clogged with the fine black ash particulates that only come from cutting fire salvage. I washed the HD2 filter daily with a high PH cleaner and plenty of water and tapped the chips out several times during my cutting day but the stock filter just wasn't capable of both filtering the air AND letting the air into the system.
A little more about the conditions I'm working in. In addition to being extremely dirty (the only thing worse would be a Mt. St. Helens type situation) it is also extremely hot. The dash board thermometer on my pick up at 1:00 quitting time the other day read 99 degrees. The only shade is the shadow behind the dead tree trunks. All the forest duff is burned up so it's just bare dry powdery dirt beneath this charred skeleton of a forest.
The weenie solved everything. And this saw never had power even close to what it has now. I'm running a Stihl 36" 3/8 X .063 light bar with Oregon 75CJ chain at .035 ground on a Silvey SDM4 and HDG6. Bury the bar in tough bull Doug Fir and it still pulls hard. Almost what one of my 661's would do but not quite. I do let it idle for 5 or 10 seconds after a long hard cut before shutting it off just to let things cool down a bit before shutting it off. I think these saws may have a vapor lock problem in this high heat.
I just ordered a West Coast Saws Bark Box for it too. I figure if freeing it up going in did that much then freeing it up going out might help too. Don't much care for NAMs (noisy ass mufflers (LOL)) but that's the price sometimes. I live in camp during the week so I won't put the Bark Box on until next weekend which means no report for a couple of weeks.
Terribly disappointed...? Never mind.

 

[Long Bar 60]

So I put a West Coast Saws Bark Box (NAM- noisy ass muffler) on it and found that a Max Flow air filter fits right on with a little bit of drilling of the filter cage and the outer plate so I did that too. Ran it all week in these ultra dirty conditions without washing the foam filter (I used the white foam as opposed to the green) and it ran flawlessly and the throttle body was absolutely spotless. I use Bel Ray foam filter oil. The Bark Box upped the power and torque but make sure to have good ear protection. I've already got a perma-headache from a concussion a couple weeks ago (knocked out cold by a widow maker) and all that noise probably doesn't help.

This saw is loud, light and powerful. I take back all my original assessments and give it a resounding thumbs up. I'll try a 41" Cannon bar on it this week just for giggles and see how well it pulls. Should be just fine based on its 36" prowess. It would probably struggle with a 50" bar but it also won't ever need to pull one.

It amazes me that Stihl can't come up with an air filter that will handle all the conditions that a timber cutter has to work in. They never have either. Those old flat flocked filters (090, 075/076, 045/056) needed to be washed numerous times every day and that was in "clean" green timber. I will never forget the first foam filter that I put on an 045. Cutting scale back in those days and I'll bet my income went up by 25%. It was just shocking the performance difference.

Oh, and another nice feature of the NAM is that it really blasts the exhaust out hard. As mentioned previously I'm cutting salvage on a burn so there's no forest duff on the ground, just bare dry dirt so the log is frequently covered with dirt or heavy dust where I have to buck it. Point the NAM at the bucking point, hit the throttle and presto, the dirt gets blown away. Nice clean cut. I do carry a wire brush on my tool belt if the exhaust can't get it clean but I mostly use it to clean the butt of rain splash dirt before falling the tree (technically snag). Most days I only have one chain to grind back at camp. Must be doing something right!

I'll post any new things I find on the 500i but for now I am really liking it. Check out this log deck. There are dozens and dozens of these decks all over this burn. The mills can't handle all the wood and there simply aren't enough log trucks to get it to the mills so they'll get hauled in later.

 

[juanroberts]

a Max Flow air filter fits right on with a little bit of drilling of the filter cage and the outer platea Max Flow air filter fits right on with a little bit of drilling of the filter cage and the outer plate so I did that too.

Hey Long Bar 60,

that is some great news. I do trail deadfall bucking and that was new and helpful info as well. I never thought of carrying a wire brush riding after a burn. I am curious which Max Flow you used, for example, the one for the newer MS660, or MS440, etc?

Thank you.

 

[Long Bar 60]

Hey Long Bar 60,

that is some great news. I do trail deadfall bucking and that was new and helpful info as well. I never thought of carrying a wire brush riding after a burn. I am curious which Max Flow you used, for example, the one for the newer MS660, or MS440, etc?

Thank you.

I don't think it makes any difference which Max Flow is used in the way I have it set up. I used the inner cage with the foam filter and then just the flat plate over that with the fastening nut. No rain shroud. The foam is just out there fully exposed. I've been told that a 661 rain cover will fit with some modifications but I have a box full of cages and plates and it hardly ever rains in this part of California in the summertime so I just used what I had. Madsen's Shop and Supply says that Equi-tee Manufacturing (the makers of Max Flow) are working on a filter for the 500i but it's not out yet so I'll continue to use what I've got unless the foam is getting ripped up regularly. It looked really good after one week. Of course, there is no brush to rip things up since it all burned in the fire. Oh, and even with the built in spark arresters the Bark Box is not legal on Forest Service ground.

Be safe out there.

 

[juanroberts]

Thanks Long Bar 60 for the insight. So while waiting on the Maxflow to arrive, I received the Outerwear. It has a tangerine color and tight fit. Hopefully its insurance in case I drop the dirtbike in the water.

On the foam center washer seal, it was letting sawdust through, and presumably dust. I made a washer from a bicycle inner tube and it is sitting beneath the white foam ring. The extra washer is an idea off the internet that is meant to create more pressure and hopefully stop sawdust from going through there. I also colored the center of the white foam washer with a black sharpie to more easily assess when it is centered.

 

[juanroberts]

Point the NAM at the bucking point, hit the throttle and presto, the dirt gets blown away.

I had been thinking in general about this very helpful post. And in particular, its suggestion of using the MS500i’s exhaust to blow the dirt off of logs.

California received a lot of rain this season. There are a lot of deadfalls blocking the trails. Big ones. On steep slopes. The rootball on these on their fall tossed a bunch of dirt up and unto the log. So, the trick of using the saws exhaust to clear the inch-thick dust off these logs has been awesome.

Maybe the air filter may get dirtier? But who cares because I prefer to change the air filter in the garage any day compared to sharpening the chain trail side on a hot day while wearing full moto riding gear.

So thanks, Long Bar 60.

-Mid Bar 28.

 

[juanroberts]

At 3:20 this guy claims to let the MS500 idle for 30 seconds before shutting it off so the ECU can reset to idle (from full throttle if you were cutting beforehand). This makes it easier to start later because the ECU thereby wont flood the motor.

At 4:30 he claims cold seize is a problem and to ensure the saw warms before cutting at full power.

 

[cheeves]

Hello,
Well I ran out and bought a 500i and I've only put about 3 tanks of fuel through it. I was really impressed until today.

Prior to today, I had only used the saw in cold weather and it was fantastic, I could take it from the warm shop outdoors (-10c) and it would start up and wouldn't miss a beat. Today, in warmer weather, the saw won't re-start when warm. It will start and die or start and if some throttle input is given, it bogs and dies. It would do this for about 30mins after use and now it's running normally. Before I take it to the dealer I'd like to know if anyone else has had these issues?
Thanks

SAME WITH OURS. HAVE 2 ...OLD COLONY FIREWOOD. 79 DOLKITA TOO!
WE LET THEM SIT AND GRAB ANOTHER SAW.
LOVE TO KNOW WHATS UP WITH THAT?

 

[bundy]

I have 2 Makita DCS401 saws that both run well and start well from a cold start. Restarting after the saws get hot is no joy. I switch off and let the hot one cool off and the saw starts fine.

 

[Hermio]

In addition to not needing a 500i, nor having the money to buy a 500i, it is to new a saw to spend that kind of money. My 461 is going like new after 5 years, and I expect to get another great 5+ years out of it. My ms290 which I use more then anything is now on its 10th year and it too is also running and starting great. Compression test last year tells me that it is very healthy also. I did a carb rebuild to address some rare bogging issues -- 20 minutes of work, $6+ in cost and it is perfect.

500i? Why?

The answer: power. My stock 500i cuts through 12" diameter white oak in 5 seconds, 18" red oak in 10 seconds. And it weighs less than other saws in its power range. Mine usually stalls out when I first start it after non-use of a month or two. Second start usually works. I think it takes several seconds for the mini-computer to make the necessary adjustments.

 

[user 122190]

The answer: power. My stock 500i cuts through 12" diameter white oak in 5 seconds, 18" red oak in 10 seconds. And it weighs less than other saws in its power range. Mine usually stalls out when I first start it after non-use of a month or two. Second start usually works. I think it takes several seconds for the mini-computer to make the necessary adjustments.

Good information. Thanks!

 

[juanroberts]

Agreed on “power”:

https://www.stihlusa.com/guides-pro...-Weight Ratio At,weight ratios on the market.“Power-to-Weight Ratio At just 13.9 lbs. (14.8 for the R version), the MS 500i features one of the best power-to-weight ratios on the market.”

You also cannot flood it because its fuel injected.

In terms of the folks that cannot start their saws when hot, can you check next time if the fuel in the tank is boiling? If so, it may be the use of more volatile leftover winter fuel in the summer…. Thanks.