TG1860G with Kawasaki FD590V will not start

[mgbstyle65]

Thanks in advance for any help.
Will not start. If i keep turning it over then i will get a single backfire through the carb.
What i have done.

Bypassed the interlock switch because it tested to be bad.
Bypassed the PTO switch because it tested bad
The weird thing about the above was that with them connected they still allowed the motor to turn over.
Replaced the Spark Igniter because it tested completely out of spec. each pin i tested showed like 3 to 8 ohms.
All of the new parts have tested good but for now, so they won't be a part of the equation I am leaving the interlock and PTO bypassed.
Removed all connectors and soldiered them directly together.
Set the valves from the flywheel markings and manual steps to 25mm
removed radiator and cleaned spot on flywheel with emery cloth and the magnets on the Igniter Pulsars and put a very thin layer of dielectric grease.
gapped spark plugs at .025

Now i have very strong spark from coils and the spark plugs
Compression on both cylinders exactly the same at 140 (this is the only thing that worries me because manual shows should be 170psi)
I tap some starting fluid in the carb to make sure its getting fuel.

Another odd thing is the steering wheel has the issue where it turns while starting. It seems like it resets fine but after about 3 seconds or so it starts
turning to the right again

Just looking for some ideas because i am at a loss. Thanks in advanced for the help.

Wes

 

[BX23S]

Welcome to the forum!

 

[Dave_eng]

What did you do with the starting fluid and how did the engine react?

Dave

 

[D2Cat]

You don't say how long you've owned the mower, but it will not start if you don't have the parking brake set.

 

[mgbstyle65]

You don't say how long you've owned the mower, but it will not start if you don't have the parking brake set.

I removed the interlock switch for the brakes and bypassed it. the relay tested bad. i have owned it almost a year. there were alot of issues that i have fixed so far.

 

[mgbstyle65]

What did you do with the starting fluid and how did the engine react?

Dave

tapped some in the carb with no difference. so far i can get one backfire or pop out of the carb and that's it

 

[mgbstyle65]

Welcome to the forum!

thanks Mike

 

[BruceP]

I work on several small-engines per week. They are all purchased used and I get nearly ALL of them all running within 20 minutes. (the others have mechanical damage and become spare-parts)

it sounds as if you have fired the parts-cannon at this thing without a lot of results. I doubt there is enough adjustment to set the valve-clearances to 25mm. However, the compression results indicate the valves are acceptable.

lets review what is needed to make engine run:
1) Compression
2)Ignition
3) Fuel

You need to walk through each of these and validate them. It sounds as if you have at least 2 of them.

Remember that an engine can run ALL BY ITSELF (not mounted in any chassis). Hence, it is easy to eliminate all "safety switches" by simply unplugging all wires between engine-chassis. You can leave the big red wire on the starter. (There are either 1 or 2 plugs...... 1 is for kill-switch, other is for charging system)

In cases where the engine will not crank due to safety-switch, just jumper from battery+ to starter to crank engine.

Once you decide how you will be cranking the engine... remove air-filter so you can spritz a little starter-spray DIRECTLY into carburetor throat.

Choke should be OPEN when using starting-spray.

BEWARE - you will have no way to KILL the engine with all the wires disconnected!!

Begin cranking engine, after it is spinning, add a spritz of starting-spray into carb throat.

There are THREE possible outcomes:
1) engine starts and runs [Stuf rag in carburetor to kill engine] (your problem is either the chassis wiring or choke adjustment)
2) engine runs for a moment (your problem is carburetor )
3) no start (Time to troubleshoot engine)

If engine seems to backfire or wants to run backwards, assume the key on the flywheel has sheared. (ignition timing is incorrect)

BTW: sanding the magnet on flywheel MAKES NO DIFFERENCE to how the ignitor fires. (Rust does not affect the magnetic field)

To check if the carburetor is metering fuel, check the sparkplugs. They should be 'wet' with gasoline.

One of the MOST COMMON no-start issues is misadjustment of the choke. If the choke does not COMPLETELY close, many engines will fail to start without starting-spray.

Let us know what you find.

 

[mgbstyle65]

I work on several small-engines per week. They are all purchased used and I get nearly ALL of them all running within 20 minutes. (the others have mechanical damage and become spare-parts)

it sounds as if you have fired the parts-cannon at this thing without a lot of results. I doubt there is enough adjustment to set the valve-clearances to 25mm. However, the compression results indicate the valves are acceptable.

lets review what is needed to make engine run:
1) Compression
2)Ignition
3) Fuel

You need to walk through each of these and validate them. It sounds as if you have at least 2 of them.

Remember that an engine can run ALL BY ITSELF (not mounted in any chassis). Hence, it is easy to eliminate all "safety switches" by simply unplugging all wires between engine-chassis. You can leave the big red wire on the starter. (There are either 1 or 2 plugs...... 1 is for kill-switch, other is for charging system)

In cases where the engine will not crank due to safety-switch, just jumper from battery+ to starter to crank engine.

Once you decide how you will be cranking the engine... remove air-filter so you can spritz a little starter-spray DIRECTLY into carburetor throat.

Choke should be OPEN when using starting-spray.

BEWARE - you will have no way to KILL the engine with all the wires disconnected!!

Begin cranking engine, after it is spinning, add a spritz of starting-spray into carb throat.

There are THREE possible outcomes:
1) engine starts and runs [Stuf rag in carburetor to kill engine] (your problem is either the chassis wiring or choke adjustment)
2) engine runs for a moment (your problem is carburetor )
3) no start (Time to troubleshoot engine)

If engine seems to backfire or wants to run backwards, assume the key on the flywheel has sheared. (ignition timing is incorrect)

BTW: sanding the magnet on flywheel MAKES NO DIFFERENCE to how the ignitor fires. (Rust does not affect the magnetic field)

To check if the carburetor is metering fuel, check the sparkplugs. They should be 'wet' with gasoline.

One of the MOST COMMON no-start issues is misadjustment of the choke. If the choke does not COMPLETELY close, many engines will fail to start without starting-spray.

Let us know what you find.

I am about to head back out there and take a whack at it again. I forgot to mention that early on, because of the backfiring through the carb, i checked to make sure the pin on the flywheel wasn't sheared and took that time to set the timing on the flywheel instead of by feeling tdc at the spark plug hole. i did tap the starting fluid directly in with the air filter off but didnt try adding more as i was spinning it over so i will try that along with your other suggestions.

I also added about a teaspoon of oil to each cylinder and check compression again. one went up 8lbs the other 10 lbs. the book says that 175psi was the lowest acceptable number. would it still fire with 140?
i will give yall an update once i try these out.

Thanks for the help.

 

[Pau7220]

Any incident cause the no start? I worked on a Briggs last week that hit a rock and wouldn't start. When the crankshaft stopped turning the flywheel didn't... it sheared the key knocking the timing off by a mile.


Edit... guess we were typing at the same time.

As far as the starting fluid use... I usually keep gasoline in a contact lens solution bottle for issues like this.

 

[lugbolt]

140 is low. Should be 200-ish, 175 at the lowest.

Check valve clearance first, although they're not known to tighten up & cause loss of compression.

What they are known for is breaking camshaft gears. Complaint #1 backfiring and #2 low compression.

 

[Pau7220]

What they are known for is breaking camshaft gears.

Set the valves from the flywheel markings

I guess when OP stated they set the valves, assumption is they checked valve action...
i.e. TDC of exhaust stroke.... exhaust valve closes & intake opens.

 

[SidecarFlip]

Got the same engine on my Cub zero turn. I've found that the coil feed wires lay on the intake manifold and through vibration, rub the insulation thin and then short out on the manifold causing the backfire issue, I sleeved mine with heat shrink tube and zip tied them to the manifold so they would not rub.

I see you have a cheapo STP junk oil filter. You need to loose that and use a quality filter with some media inside. Those STP filters are worthless and that motor relies on clean filtered oil which could be why your compression is low. Junk inside eating away at the rings. When you pulled the overhead covers was there any crud (blowby) in the covers? Telling sign of internal wear. I have 1500 hours on mine, runs like a top but is a gas hog.

 

[mgbstyle65]

140 is low. Should be 200-ish, 175 at the lowest.

Check valve clearance first, although they're not known to tighten up & cause loss of compression.

What they are known for is breaking camshaft gears. Complaint #1 backfiring and #2 low compression.

Thanks for the reply. I was thinking that but its not supposed to be the one with the plastic gear. Do you think it could still be a broken camshaft? Also I set the valves, both of them at 25mm because the manual said from 24 to 28mm, should i change that? Also set the plugs to .025... thought it was funny the manual put it in two different measurements for the valves vs the plugs, a little confusing at first.

 

[mgbstyle65]

Got the same engine on my Cub zero turn. I've found that the coil feed wires lay on the intake manifold and through vibration, rub the insulation thin and then short out on the manifold causing the backfire issue, I sleeved mine with heat shrink tube and zip tied them to the manifold so they would not rub.

I see you have a cheapo STP junk oil filter. You need to loose that and use a quality filter with some media inside. Those STP filters are worthless and that motor relies on clean filtered oil which could be why your compression is low. Junk inside eating away at the rings. When you pulled the overhead covers was there any crud (blowby) in the covers? Telling sign of internal wear. I have 1500 hours on mine, runs like a top but is a gas hog.

I switched to wix this year after hearing about fram and stp filters. thanks for the heads up. i will double check the coil wires too. it was very clean inside the valve covers

 

[Pau7220]

manual said from 24 to 28mm,

That's between .94" and 1.1"
I hope that's a typo.

Do you think it could still be a broken camshaft?

Did you check the valve action? TDC of exhaust stroke.... exhaust valve closes & intake opens.
BOTH CYLINDERS.

 

[thebicman]

I do hope you are making a typo on the valve settings. Its 0.25 mm which is 0.010 inch. Plug is correct at 0.025 inch.

 

[mgbstyle65]

That's between .94" and 1.1"
I hope that's a typo.

Did you check the valve action? TDC of exhaust stroke.... exhaust valve closes & intake opens.
BOTH CYLINDERS.

yeah sorry. .024-.028in and i did .025in

 

[mgbstyle65]

yeah sorry. .024-.028in and i did .025in

and i pull the radiator to set by the flywheel

 

[lugbolt]

Thanks for the reply. I was thinking that but its not supposed to be the one with the plastic gear. Do you think it could still be a broken camshaft? Also I set the valves, both of them at 25mm because the manual said from 24 to 28mm, should i change that? Also set the plugs to .025... thought it was funny the manual put it in two different measurements for the valves vs the plugs, a little confusing at first.

yeah to my knowledge they are still using plastic gear, even the new replacement. On some engines, yeah they switched to metal, but you also had to change the crank spur gear, meaning pull the crankshaft out. Kawasaki Mules were notorious for it, on the KAF620's, pre A5 models (pre 1999). 99- were all metal gears, and they made a little more noise. Those are FD620D engines; and some of them were also used on generators and mowers, but to my knowledge, Kubota didn't use the 620. John Deere did, 425 and 445, among others. Did many a plastic gear replacement on those 425's. Likely a hundred or thereabouts. I know it was a bunch of them. Then about 50 Mules over the years.

.25mm is fine. 25mm is a shade less than one inch. Plugs .025" is fine. Yeah the manuals are weird, all of the Kubota manuals are. They are written in Jinglish I think.