Stihl bg55 blower

[hlw49]

Let me give you one more tidbit of information. Take the fan off the unit, left handed nut I think, and see if it has blown the crankshaft seal out that is behind the fan. This is from the guy where I work that works on them all the time he is a real guru. Really knows what he is doing on two stroke.

 

[lbrac]

When I have problems starting a small 2-stroke engine after priming and choking it and pulling it over a number of times, I go through a troubleshooting routine:

I pull the plug to see if it is dry or damp with fuel. If damp, I turn the choke off and open the throttle fully while I pull it over with the exhaust pointing down. This will allow excess fuel to be pumped out of the lower end and cylinder and out of the exhaust port. I then place a finger over the plug hole and pull the engine over slowly to check for a strong suction/pressure pulse as the engine turns over. If it is strong, I place my palm over the carb inlet to check for a strong vacuum when I pull the engine over slowly. If the vacuum/pressure tests are poor, it is time to consider disassembling the engine to inspect the piston and ring, and the cylinder condition, and/or the lower end bearing(s) and seals. I have found engines with low compression that had a ring stuck in the ring groove of the piston, although there was no other damage to the piston or cylinder wall.

If the vacuum/pressure tests are ok, I connect the plug to the plug wire, ground the plug body, and check for spark when I pull it over. If ok, I reinstall the plug, if not, I try a new plug to see if it will spark when pulled over. If no spark with either plug, it is time to troubleshoot/repair the ignition system.

If the plug sparks, and it was dry when I first removed it, I spray starting fluid into the carb inlet before trying to pull start it. If the engine fires but cuts off right away, the fuel system is due for troubleshooting/repair.

This procedure will not catch every possible problem, but it doesn't cost anything, and it is relatively quick to perform.

 

[Tommyb2401]

Your initial post didn't give much information to really diagnose the problem. So the advice and questions was simply to get more information, to steer you in the right direction.
For any tech, "what's the problem" is our initial question we all ask ourselves. What are the symptoms is the next. And so forth and so on. Until the culprit is narrowed down to the problem.
When you have eliminated the impossible, whatever remains, however improbable, must be the truth?
You can either spend the money on a shop to diagnose the blower. Or spend the money on the tools needed to diagnose it.
Or spend the money on a new or used one.
Either way, it's mechanical. And not going to last forever. So we're not trying to lecture you. Just get all the information we need to diagnose, sight unseen, your equipment through an online forum.

I apologize if I came off as a a** what information is it that I need to provide

 

[PTmowerMech]

I apologize if I came off as a a** what information is it that I need to provide

IIRC, you've been asked a few questions so far.

 

[bertsmobile1]

2 strokes need both primary & secondary compression to work
They rely on the crankcase oil seals to do this.
Two strokes require high compression to work depending upon the model it can be anywhere from 110psi to 85psi ( on my gauge ) and 1 psi lower it is all over red rover
A 4 stroke can start with as little as 50 psi .
The BG55 is the bottom end blower so repairs will most likely exceed the replacement price.
When most try to start by dropping fuel down the plug hole they use way too much
A single drop should cause the engine to fire about a dozen times .

Then we have spark plugs
New plugs have no glaze on the insulator nose because the EPA demands 0.000% Pb in the exhaust and you do get a minute amount of lead from the glaze
Add to that the fact that modern fuels ( which are not petrol ) are highly conductive at compression pressures if the plug gets slightly damp then the voltage will track down the plug .
This leaves a conductive path that the spark will short down forever unless burned off.
This is what causes the "bad out the box" syndrome people who have no idea flap their gums about trying to sound intelligent .

So pull the muffler & carb off have a good look at the piston & bore at the top & bottom
If you can see any marks other than the cross hatching then the bore is toast
Get a fresh plug and warm it till it is too hot to touch with your hand .
Put a drop of fuel down the plug hole, insert the hot plug finger tight and give it some pulls trigger fully open.
If it does not go bang then time for a new barrel & piston.

Bottom end 2 strokes usually only have 1 piston ring and that ring has to do a lot of work .

 

[PTmowerMech]

Thanks Bert. I didn't know the bottom end of a two stroke needed compression too.

 

[bertsmobile1]

Crankcase compression is called the pprimary compression and during that a ot of the oil comes out of suspension and condenses inside the crank case which is why you often find them very oily
The combustion compression is called secondary compression

If you can drag yourself away from repeats of the Peanuts Christmass specials search the WULF stepped piston 2 stroke engine

 

[PTmowerMech]

Crankcase compression is called the pprimary compression and during that a ot of the oil comes out of suspension and condenses inside the crank case which is why you often find them very oily
The combustion compression is called secondary compression

If you can drag yourself away from repeats of the Peanuts Christmass specials search the WULF stepped piston 2 stroke engine

Which also explain a crank seal leak, when the crank seal is on the side, and not the bottom. As in vertical engines.