TS500i question

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Greenmachine

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... Is the crankshaft supposed to move smoothly? I've one on the bench that seems to have some slingshot-ish effect as i rotate it. The top end is removed. Does not feel like a broken bearing to me.

And how can i test the injector while it's disassembled? E. G., to see if there's no grit in it?

Thank you AS.
 
There is a generator on the back side of the flywheel. The magnets are all the way around flywheel, with a stator windings mounted to the crankcase under the flywheel. That is probably what you are feeling. Sometimes concrete and metal bits can make it feel gritty, but a bumpy feeling as it is rotated is normal.
Inertia and airflow will expel most of the dust and debris once it is rev'd up.
At least that's how it's designed, anyway.
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A careful visual inspection of the bearing cages; that the ball bearings are not jumbled up, and there is no up & down play in the bearings at all.
This also goes for the lower rod bearing, checking for cracks in the rod bearing cage.
Testing of the injector.....
Dirt needs to be cleaned off the connections first.
EPA says all constantly wetted hoses should be replaced once disconnected....:crazy:
With the muffler forward, looking from above. The far left hose is the outlet from the fuel pump/primer. It goes to the left-most nipple on the injector. If your primer is hard to pump, then it may be that the tiny screen just behind the inlet nipple of the injector. ( It pulls out with a pair of common pliers), which this is not in the Stihl service manual for some reason.....
Make sure your fuel filter is replaced first to deduce that as the source of the restriction. Personally, I would only use the OEM magnetic filter. Just because it looks clean does not necessarily mean it is unrestrictive. I've seen some filters that looked new, but you couldn't blow through.
Ok, on to the testing of the injector.
Gently pump to 3 or 4 psi on the inlet to the unpowered unjector until it bypasses.
It should not bleed down below 2.5psi. (note that when performing this test the fuel cap should not be shut, as pressure will build up, causing a false reading).
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Another test of the injector with it removed from the engine, which you won't find in any Stihl manual is;
Spray a little wd40 on the injector nozzle outlet while it's under pressure, and holding around the 2.5psi range.
If there is any air bubbling from the injector, then the injector will need to be replaced. This indicates the injector's rubber pintle seal, that is not replaceable, is damaged.
If it is not bubbling, and not holding the 2.5psi, then there is a pressure regulator behind the exit nipple, which consists of a small spring, and needle, similar to ones found in a common chainsaw carburetor. The spring may be weak, or the needle faulty. This is a non-serviceable part, but if you are someone like me who has several dozen "dud injectors" lying around.......
I have had luck switching these components with faulty injectors that had other issues besides the needle and spring, which were still good.
Hope that helps.
 
alexcagle this is such a generous response. Thanks for taking the time to do this!!

Just to reiterate - there's no grittyness. It's like there's a rubber band in there when I rotate it. I twist the crank, it pushes back a bit then and then springs forward again. Bearings look good. I'll report back again soon.

Edit. Sorry reread your post and you say this it s normal. Thanks!!!
 
I'm helping out a fellow who loaned his out and someone left it in a bucket of water. I opened the cylinder and yes, muddy silty water. Chainsaw sacrilege.

I gave it a pull or two and no spark with a good plug.

The injector pump pumps well. I sprayed out the lines and nipples on the injector. Haven't tested it yet but it looks fine if that means anything. Meaning there's book grit in the nozzle.

I wonder if the computer is OK. Seems really water proof.
 
The spark test has to be performed with the spark plug installed.
The crankcase pressure sensor will spark one time unless it gets correct feedback from the sensor in the bottom of the crankcase.
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As blsnelling said, if the crankcase sat for more than 24hrs with water present, your bearings are most likely toast.
Lower rod bearings are prone to ruining from rust quickly from water......Silt, even worse. If you start it with sand behind the bearings, it won't last until lunch. It would have to have the seals pulled and flush the bearings out.
Cranks for that saw run about $250.00 for that saw from Stihl.
I have a good used crank for one if it's toast after all.
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Here is a Partner K950 that got left in a ditch overnight, next to the Arkansas River here in Tulsa. It rained several inches that night. They drug it out a week later. Muffler was completely full of sand.
I was able to save the saw, but needed a donor crank, and new bearings. 1455650479822.jpg
 
Hmmm. Im in deeper than i thought.

I sprayed the injector out with carb cleaner.

Ive never split a crankcase before. Better man up i guess.

Thanks for that offer i may take you up on it.
 
What i did was this: i flushed the bearings and shopvac'd at the same time until no brown carb fluid pooled any more. It wasn't nearly as bad as the photo. I made a point of squirting into the bearings from two different angles.

I made my wife so mad because i stunk up the house with carb cleaner at bedtime. I guess I'm saying i think the silt is gone, but what do i know...

So seems like you guys are saying new bearings and seals.
 
What i did was this: i flushed the bearings and shopvac'd at the same time until no brown carb fluid pooled any more. It wasn't nearly as bad as the photo. I made a point of squirting into the bearings from two different angles.

I made my wife so mad because i stunk up the house with carb cleaner at bedtime. I guess I'm saying i think the silt is gone, but what do i know...

So seems like you guys are saying new bearings and seals.
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Possibly so, depending on how long it was allowed to rust, and the degree of contaminants ingested.
In a contamination that bad, it's near impossible to get all the grit out without disassembling it to make sure. Aluminum pistons and brittle piston rings are not real forgiving to sand contaminants.

WD-40 makes a better flushing agent.
It's clean, lubricating, water displacing, not nearly as caustic, and will kill way less brain cells in the process. LOL
Not to mention keep the Mrs about 5 levels less angry.
Their nail remover smells just as bad to me.....
Funny that you mentioned shop vac-ing the carb cleaner, and stinking up the house.
I myself once rebuilt an automatic transmission in my mom's kitchen overnight back in high school.
She was not real happy when She got home late, and in hind site, I can see why. Lol !!
I use lacquer thinner in a WD-40 squirt bottle to clean, degrease parts, and prep surfaces. However, I have a fume evacuation system that gets rid of the stinky air.

The carb cleaner isn't what you want to use in the injector either. It's a low pressure system, and not designed for caustic liquids like carb cleaner. Although, it probably didn't hurt it, I wouldn't leave it sitting inside the injector. It may eat at the o-rings, so you may want to flush it with an easy shot of WD40 with a straw nozzle in the inlet until it bypasses out the other side.
They don't require cleaning, as they are not designed like a lot of automotive injectors that are inside the combustion chamber, and get subjected to the high temperatures and violent explosions of the combustion process. That's also why those require higher pressure to operate.

If you need to separate the crankcase, get a repair manual, as there are ways to do it incorrectly that can end up very costly and still end up with a short lived saw.
 
alexcagle thanks again for taking the time to educate me. Thanks too to blsnelling for chiming in. Basically I come here and get free repair mentorship. My heartfelt thanks.

I will do as you suggest with the WD40. And yes, my wife was royally pissed off. My man-cave peace was utterly smashed. Your transmission story is so funny. I just pulled my first transmission out. Ten hours under a rusty Chevy 2500 in the middle of a field. Heh. Got it done though.

In our old Montreal apartment I built a vacuum tube amp in our kitchen. Wifey was very accommodating then.
 
Just a quick update. I got this running thanks to all your help. As we discussed, time will tell if I've done an adequate job flushing silt out of the crankshaft. You were both correct there was the slightest bit of rust noticeable on one surface of the crankshaft bearing - namely the outer edge of the inner race on one bearing.

Thanks Again and I'll keep the thread updated for future reference to other AS users.
Dan
 
alexcagle thanks again for taking the time to educate me. Thanks too to blsnelling for chiming in. Basically I come here and get free repair mentorship. My heartfelt thanks.

I will do as you suggest with the WD40. And yes, my wife was royally pissed off. My man-cave peace was utterly smashed. Your transmission story is so funny. I just pulled my first transmission out. Ten hours under a rusty Chevy 2500 in the middle of a field. Heh. Got it done though.

In our old Montreal apartment I built a vacuum tube amp in our kitchen. Wifey was very accommodating then.
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Your are welcome.
I evidently missed the reply a couple months ago....LOL
I'd run the mix with double the oil for a while to fend off any heat caused by the microscopic roughness of any unseen rust. I still wouldn't vest much hope in it lasting. I've tried to save cranks a couple times, and at 10,000 rpm, heat builds up quick on rough bearings.
 

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