Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Good morning my name is ***** ***** I can help you diagnose this issue. first off it sounds like you have a failed rodbearing but we need to look at a couple things first
have you pulled the spark plugs? if not do that and see what color and condition they are in. run the engine and see if one cylinder is running cooler than the other
oh no that's not good at all. I would recommend a compression test at this point to verify but it sounds like you have an internal failure. most likely a rod bearing. possably look down into the cylinder that had the smashed spark plug and see if the top of the piston has damage.
absolutely it can be fixed. it will all depend on how bad it is really. I would tear the unit down and get a good look at it. price out the parts and labor, in most cases its actually cheaper just to buy a new engine and replace that way....especially if you are paying labor. If you plan on doing the work yourself it may be more cost effective to rebuild yourself.
sorry to hear about the trouble
thanks for using JA and when you have a moment please rate the service.
on the first machine I would still compression test it. I use the website partstree.com for all the parts break downs
on the second machine test the voltage at the battery and make sure the stator is making 13+ volts. no volts not juice to make the spark
anything above 100 psi is good
so that proves that piston rings and valves are good. you mentioned that the suspect side may have hit the spark plug correct? how does the top of the piston look?
I wouldn't feel right speculating at this point. not being there to hear it.... you first stated it sounded like an exhaust noise, maybe an exhaust gasket? again...with out hearing it. I'm sorry but I don't want to point you in the wrong direction and cost you money that you don't need to spend
the glare makes it a little hard to see. how does the crank look from that side?
sounds like you made good progress! I wouldn't blame the govenour just yet.... it sounds to me like you have a carb/fuel related issue
have you tried an additive like sea foam in the fuel? it sounds like you may have picked up some debris and the low idle jet may be partially clogged. heck... maybe just tear the carb apart and clean the heck outta it and see if that helps
not so much...don't have any technical info on Scag. I will say you will need to figure out if the 2 issues are related or separate. I would suspect that they are related only because this all started at once. PTO requires seat switch and key on. battery drain caused by wiring on the engine? key switch wiring jacked up? I will opt out so that a scag tech with wire diagrams can pick this up
WHat engine is this? Kohler? The stator is under the flywheel and it has to put out a minimum of 28 volts AC. Check with it unplugged from the voltage regulator. If it puts out 28 + Ac volts, it is good, plugg the regulator back in and test with meter on DC volts, output should be 1/2 of the stator around 14 volts DC. f it does, be sure the wire from the regulator output goes to the battery posiitve, at starter solenoid or keyswitch. If not, it will not charger the battery. If battery voltage drops below 12 volts, the pto clutch will drop out or not engage.
Model number? It was there, two wires coming from under the flywheel to the voltage regulator?
See page 8-14 in the manual above. Just as I stated.
Do you have battery voltage at the output terminal of the regulator? If you do, the stator has to be bad.
If clutch is throwing sparks , you have problem with the clutch, should be no place for spark to show. Sealed coil and harness!
Clutch is the largest electrical load on the engine. If it pulls too much amperage, the charging system can't keep up.
What is the output of the regulator?
On Kohler it is the center connection, purple.
It should read battery voltage before starting and well above battery voltage when you run engine at high speed.
Follow the purple wire to see where it goes, has to go to the battery posiitve or it will not charge.
What does it read running, that is what would have to charge battery.??
Is meter on DC volts?
Battery can't be more than 14 volts DC!
Now running at high speed.
So it is charging ! And very good!
Don't know, but charging system is working!
What is it reading with key off, and what is it reading running?
OK, the purple wire is not going to the battery. Take a jumper wire from the battery , to the purple wire at the regulator and run engine while checking battery voltage.
OK, so back to the stator , what was the two white wires reading unplugged from the regulator and engine running at speed.
Meter on AC volts.
red on one white, black on the other, read at same time.
Ok, your stator is good. So by that, the regulator is not working, it should have output well over battery voltage.
It's not working!
If the purple wire has battery voltage at all times, key off or on, it is wired correctly.
Does it with key on?
Ok, it is wired correctly.
Typically regulator is killed when a person jumps the unit off with a running vehicle.
Run cylinder test with engine idling. Loosen spark plug wires and remove one at a time whilr idling, engine should continue to run. If engine dies when either wire is removed, the opposite cylinder is not firing, I would suspect a bad coil.
If not a spark problem, a carburetor problem. Has carburetor needle seat and float been checked?
The wet cylinder is not firing.
Wet plug is always a plug that is not firing.
Does it have spark?
WHat engine CH, CV, SV, ??
Hydraulic lifters. May be valve leaking?
Find TDC by using probe in cylinder while turning manually, You want both valve rockers up, which is the compression stroke. With leak down test, yo put pressure in the cylinder and hls it, with shutoff valve , to see if it holds.
By test , your exhaust valves are not seated.
See if it has spark when attached to grounded spark plug.
My thoughts are your valves are not seating!
DOes left cylinder have good spark? I think you ave a bad coil on the wet cylinder.