Oops, Ran over my 400.

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

M. Kulp

ArboristSite Lurker
Joined
Feb 11, 2023
Messages
14
Reaction score
9
Location
NE Texas
Hello, everyone. I Just did something very stupid. I let a new worker use my stihl 400 in the wood lot. He left it in the weeds beside the woodpile. I went to hook up the chipper that evening after dark, and slowly drove over the bar. Something didn't feel right, so I backed up, turning. The dump truck tire smashed the chain brake, the bar, 3 cooling fins, and the chain and sprocket cover. Thankfully, the saw still runs. What Now!? I've got a stihl 391 I could use for parts, but am not sure what is interchangeable. Any advice? Is there a good place to get parts saws? Chainsaw parts? What is the longterm effect of the fins being broken? I'd better get the saw fixed, or a replacement, it was the boy's favorite. And I want to keep the worker, he is conscientious and smart, really it's my falt for driving that close to the wood pile. Thanks in advance
M. Kulp
 
Hello, everyone. I Just did something very stupid. I let a new worker use my stihl 400 in the wood lot. He left it in the weeds beside the woodpile. I went to hook up the chipper that evening after dark, and slowly drove over the bar. Something didn't feel right, so I backed up, turning. The dump truck tire smashed the chain brake, the bar, 3 cooling fins, and the chain and sprocket cover. Thankfully, the saw still runs. What Now!? I've got a stihl 391 I could use for parts, but am not sure what is interchangeable. Any advice? Is there a good place to get parts saws? Chainsaw parts? What is the longterm effect of the fins being broken? I'd better get the saw fixed, or a replacement, it was the boy's favorite. And I want to keep the worker, he is conscientious and smart, really it's my falt for driving that close to the wood pile. Thanks in advance
M. Kulp
Oops. sell as a parts saw, get another one and don’t do again 😉
 
Hello, everyone. I Just did something very stupid. I let a new worker use my stihl 400 in the wood lot. He left it in the weeds beside the woodpile. I went to hook up the chipper that evening after dark, and slowly drove over the bar. Something didn't feel right, so I backed up, turning. The dump truck tire smashed the chain brake, the bar, 3 cooling fins, and the chain and sprocket cover. Thankfully, the saw still runs. What Now!? I've got a stihl 391 I could use for parts, but am not sure what is interchangeable. Any advice? Is there a good place to get parts saws? Chainsaw parts? What is the longterm effect of the fins being broken? I'd better get the saw fixed, or a replacement, it was the boy's favorite. And I want to keep the worker, he is conscientious and smart, really it's my falt for driving that close to the wood pile. Thanks in advance
M. Kulp
Smart would have been if he had put the saw where a truck cant hit it, like close to a tree or something. No replacement for experience.
 
Heck if he's letting it go for $150.00 I'd pay that and the shipping.
Smashed up parts saws are a gamble at best, so many have came my way for refurbishment, most went back out costing the owner much more than the saw was actually worth. Once they are mauled over by a machine like a skidder or a truck there is more damage than meets the eye before disassembly.If the OP has the time and experience and patience then sure go ahead and fix it but most business minded people don`t.. They just want a working saw to keep the money flowing.
 
I feel your pain. I laid my Stihl Professional Arborists saw next to the front tire on one of my customers trucks (get my trimming done for free) and he pulled forward and his rear duals on his chipper dump truck, wiped it out (literally). It went to the landfill (flattened) and I replaced it with an Echo top handle CS for half the cost. Good saw after doing a muffler mod. 400 versus 700+.

In fact, I sold my MS Stihl and replaced it with an Echo Timber Bear. Modded the muffler and the air cleaner (Stokel foam air cleaner and velocity stack) and pulled the limiter caps. Nice saw. Only Stihl's left here is my 42+ year old 028 and my 090 and 075 I bought new, way back when, not for sale
 
Smashed up parts saws are a gamble at best, so many have came my way for refurbishment, most went back out costing the owner much more than the saw was actually worth. Once they are mauled over by a machine like a skidder or a truck there is more damage than meets the eye before disassembly.If the OP has the time and experience and patience then sure go ahead and fix it but most business minded people don`t.. They just want a working saw to keep the money flowing.
Who said I would rebuild it?
 
I'd fix it. The bar, chain, and sprocket are just consumable parts anyway. The bar cover and chain brake assembly are pricey, but certainly not cause for pitching the saw.

As to broken fins? They only provide cooling. A smart user might use that saw for twenty years without over heating it. A smarter user would probably buy a new cylinder, bolt it on along with his new bar cover, and restore the saw to working order.

While getting down to the cylinder, if you find other broken stuff, it would be time to re-evaluate. In my experience, motor mounts and anti-vibe features usually get hurt first when you drop them out of a tree or run over them.

I'd even consider picking up the broken fin parts and seeing if they could be welded back on with some of the propane soldering rods. It's not like you are going to be out much if it didn't work.
 
I'd fix it. The bar, chain, and sprocket are just consumable parts anyway. The bar cover and chain brake assembly are pricey, but certainly not cause for pitching the saw.

As to broken fins? They only provide cooling. A smart user might use that saw for twenty years without over heating it. A smarter user would probably buy a new cylinder, bolt it on along with his new bar cover, and restore the saw to working order.

While getting down to the cylinder, if you find other broken stuff, it would be time to re-evaluate. In my experience, motor mounts and anti-vibe features usually get hurt first when you drop them out of a tree or run over them.

I'd even consider picking up the broken fin parts and seeing if they could be welded back on with some of the propane soldering rods. It's not like you are going to be out much if it didn't work.

I remember one saw being brought in that the owner claimed it only got bumped lightly and just the top handlebar got bent some. That saw ended up costing about half of what a new one would cost out the door. Upon closer inspection the top cover had the cylinder fins imprinted into it, the cylinder was broke about 3/4 the way around the cyl base , just a couple top fins bent somewhat, the chain bar was twisted a good bit and upon removal both bar studs had been pulled out some and the bar pad cracked through and through into the oil tank. Thr fuel tank was split where the top handle attached on the right rear side, when I called the owner he couldn`t believe there was that much damage so I had him come in and see for himself , all damage was documented in pics as the saw was disassembled part by part. After looking it over he still wanted it repaired with all new OEM parts. The saw was bought new at the dealership I was working at the time, the owner of that shop would not do any mechanical rebuilds due to not wanting to guarantee repairs, the saw owner remembered I was working there when he bought the saw so he approached me to rebuild it.
 
I try to put my saws down where they can't be reached by vehicles just for this reason. Or better, put them back in the truck or UTV. Also when you feel something funny under the wheels, driving back over it is probably not the best idea. Yea I have done it too.

I have seen air cooled two stroke motorcycles run fine with a few broken fins. The cylinder will run a little hotter but it will probably be fine. If it overheats and seizes then you'll be replacing the cylinder (if it can't be rescued), which is what you'd do to repair the damage. There are people who can weld fins back on but it's tricky and probably costs near what a cylinder would.

If the damage is only what you said, I'd fix the brake and cover and get a new bar and run it.
 
@firekindler

What say ye about broken/crushed fins and operational functions of a saw?

(It'll run fine, errr, mostly!)
I believe Stihl once said no more than two broke fins would be ok on a 066 cylinder . I prefer to have them all on, especially if the saw will see long extended cuts where heat really builds up. I never know how a saw owner is going to use/ treat a saw after it leaves my hands. Light cuts or liming would be fine but milling or long rips could overheat even a fully finned cylinder.
 
Back
Top