What's the next thing I should look for?

virtual_guy

virtual_guy

Member
I'm at my wit's end. You all led me in the right direction when we found a scored piston. I changed it and the cylinder. Sealed it back up with Loctite 515 and with a coat of oil on the cylinder wall. Compression checked at about 125-130psi. There's a good blue spark and the spark plug is wet.

Won't fire.

The air filter is new. I checked the spark arrester and it was clean, tried to start with the spark arrester off.

Still won't fire.

I checked that the alignment pin on the flywheel is intact and the flywheel is seated on it correctly.

What can I check next other than the direction to a dumpster? Surely I'm close to getting this POS running :LOL:
 
The next thing you should look for is the engine model number. Since you started a new thread, we can't possibly remember what engine or mower you're talking about. You need to tell us again.

Try some starting fluid or some other spray you know will start engines. See if it will sputter with the spray. If it hits 2 or 3 times, then you know it's the fuel or the fuel delivery system.

Some ideas...
  • Is the fuel in the tank AND the float bowl fresh ??
  • When was the last time you removed the float bowl and looked for water ?
 
Ok ok in my irritation and haste I missed an important point.

It's a Poulan Pro PP5020AV chainsaw.

It has a new carb on it and I checked the flywheel key...a couple times.

I have a new spark plug and the one I pulled out. Both produce good spark as far as I can tell and I've tried both with the same results.

I'm confident with the fuel but I'll check for water. At least it's something to look for.

I don't have any start fluid but that's worth trying.

Thanks!
 
Ok. Get some real starting fluid. Remove the spark plug and Make sure the spark plug is dry. Spray a VERY small amount of starting fluid into the plug hole. Install plug and try to start it. It should fire a couple times. If it doesn't you have either a spark or compression problem. If it fires spray a small amount into the carb throat and try to start it. If it does not fire you probably have a primary compression (crankcase) problem. You would need to do a pressure and vac test on it. If it fies and runs for a second or so you have a fuel delivery (carb) problem.
 
getting rebuilt blue smokes to fire is always problematic
My usual method for obstinate ones is to warm the spark plug up in something else till it is very uncomfortable to hold with a gloved hand
The quickly fit it loosely, say just barely finger tight ( ouch it was hot )
This helps to vapourize the fuel, prevents fuel fouling the plug & allows the engine to be cranked substantially faster .
All of the above make for easier starting.
When it does fire up ( note do not close the choke ) run the engine for a good 5 minutes or so then let it cool down & tighten the spark plug .
Many a Bantam engine required being towed quite a long way in first gear before they gave in a and fired .
 
bertsmobile1 said:
getting rebuilt blue smokes to fire is always problematic
My usual method for obstinate ones is to warm the spark plug up in something else till it is very uncomfortable to hold with a gloved hand
The quickly fit it loosely, say just barely finger tight ( ouch it was hot )
This helps to vapourize the fuel, prevents fuel fouling the plug & allows the engine to be cranked substantially faster .
All of the above make for easier starting.
When it does fire up ( note do not close the choke ) run the engine for a good 5 minutes or so then let it cool down & tighten the spark plug .
Many a Bantam engine required being towed quite a long way in first gear before they gave in a and fired .
Click to expand...
I always used High Gear to help start a towed vehicle....
 
What grade of gasoline are you using, if 87 octane it probably will not start. Most chainsaw Operators Manuals state using 91 octane or higher. I use 93 octane gasoline in all outdoor power equipment & my pickup. Read page 9 in Operators Manual concerning fresh 87 octane gas & 40:1 two cycle synthetic oil preferably Poulan brand. If you have a 1 gallon gas container mix 3.2 oz. of Poulan/ Weed Eater Brand 2-cycle synthetic oil with fresh gasoline & just give 93 octane a try. Let us know how it goes, thanks, Mark

Suggestion: When posting in the future start with equipment type, name brand, year, model & serial numbers & any other information you can provide, thanks, Mark
 
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