OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Tecumseh / Kirby Engines Hk25 can’t start

Hi all

New to the game so need some guidance

Picked up an old victa imperial 16 inch cylinder mower which has a hk25 engine and I believe hadn’t run in a while

Initially had no spark even with new spark plug. Had no readings on ignition coil so replaced it, cleaned up the magnets and flywheel etc and now have a spark

Now onto the next area. Put in fresh fuel, drained oil and put in fresh oil but can’t still get it to start.

The Carby is quite dirty and I plan to replace with aftermarket or clean this up. Float valve drips fuel at the moment too

Would this be the next step or should I look elsewhere.
What else can be done to get this going?

Thanks

Hi Darth,
Get some starter fluid and give it a squirt into the carby throat and see if that fires it up. If it fires your problem is with the carby

Thanks. I’ll give it a try this weekend.

I need to find a replacement flywheel nut now as I sheered the nut when removing it today.

Should I put any fuel into the spark plug hole or not at this stage?

You can try a bit of fuel in the plug hole but the starter fluid is a bit more explosive and often when I have problems starting an engine I find a squirt of starter fluid seems to wake a motor up. Don't use to much, just a quick squirt is all you need to see if the motor is going to run, then you go from there

Hi Normk

Unfortunately starter fluid or fuel into spark plug hole didn’t work.

There was a good puff of black smoke or dirt come out of the muffler but can’t get it to start.

Any ideas?

Well that tells you spark is working. Pull the muffler off and try again, just incase the muffler is clogged

Ok thanks

I’m a little inexperienced on this.

The muffler was off already.

I may need to replace the carby as the float valve leaks. All the fuel likes are clean.

Would that be the next logical step?

Ok if you can't get it to attempt to start with the starter fluid it is time to stop working on this motor and bin it. The carby is not the problem, the starter fluid bypasses the carby, so don't waste anymore time on it

No problem. Thanks for the help

Honestly I was planning to do an electric conversion but if it was all possible to get the motor going I would try

The good thing is that i haven’t spent anymore than a new spark plug and ignition coil.

And that is why you do these tests before throwing too much money at them. New horizontal shaft motors are pretty cheap

Hi normk

Thought I would try again today with the starter fluid and using a drill to spin flywheel.

Used a bit more than a squirt. Followed can instructions and said 5 seconds and did both the carb intake and also spark plug hole.

Got it going once to fire up and then it stopped obviously but couldn’t do it again after I let the engine rest for an hour.

So I’m assuming the carb needs a clean or replacement?

Yep that proves it will run so carby is the problem

Thanks. Looks like this will be my Friday job of rebuild. Pending condition then a new carby online.

Thanks for the quick replies. Much appreciated.

Let’s see where this next step takes me.

Hey normK

Got the engine going today after much struggle.

New carb and fuel pipe. I am not sure I can provide a video of it running. Once I got it going on numerous times once I added throttle it would die

Sounds like not enough fuel is getting to it. I’ve played with the mixture on carb but no luck.

Any thoughts?

Try closing the choke partially and then see if you can open the throttle slowly

Thanks.

That’s how I got it going initially. Choke was one notch from closure. Once I put throttle on it died

I tried a few combinations and even adjusted the mixture on carb

Even tried adjusting the throttle at the engine instead of at the handle.

I'm guessing it has an air leak on the inlet somewhere

Thanks. I’ll take a look at the next step

Hey Normk

Still no luck. I’ve put in new gaskets around carb. Readjusted fuel lines to ensure no kinks

Took off the breather today to check any clogs but no luck

Got the engine to run once but then couldn’t get it going again.
Adjusted the mix while it was running and it didn’t change much but once touched throttle it died again.

Does fuel play a part? I’m using unleaded 91. But should I be looking for something else or 95? Was a thought

Are you trying it with starter fluid. Try another plug

have tried with starter fluid. That’s how I got it running the first time and partially the other times.

I’ve gone ahead and cleaned the old carby this morning. Will swap it back and see if that changes things as I’ve read the aftermarket ones don’t always work.

In terms of spark plug. I’ve used both the champion CJ8 and also the NGK 6BS. Any others to try?

I never trust any spark plug, I had a mower dropped here last week and it took 3 plugs before it fired first pull and ran perfectly

I’ll try a few new ones then.

Thanks for the help.

Hi Normk

I showed my video of the running mower to a local mower shop and going through all the things I’ve done.

Shop believes the mower isn’t getting enough fuel. I had cleaned the tank before using it and new lines and new carb have gone in

The cap has a pin size hole on top whether it’s factory or not, am unsure. Whether it’s big enough to vent?

Also thinks maybe the choke isn’t fully closed. When I look at the replacement carb, the choke doesn’t close all the way but also has a small hole in it on the outer edge.

What do you think? Anything I should try?

If you can't get it to give a flutter on starter fluid then lack of fuel I don't believe is the issue unless it is flooded. And the breather on the cap is not the problem because you have had the cap on and off and therefore the tank has a volume of air in it so fuel flow would not be a problem, the breather hole problem would only come up if the motor had been running enough to cause a vacuum in the tank

Might be flooded due to the times I’ve tried to start it and failed

I’ll see what I can do with that now

I flooded my chainsaw yesterday and it took me ages to get it going after I stripped everything down on it

Well I think I have another problem. The flywheel
Key has cracked in half and split in some way

So I’ve ordered a new genuine replacement key.

Before that I got it popping a few times and sounded like it wanted to start but didn’t.

Timing is probably off due to key amongst other things.

This will be a labour of love

broken keyway doesn't help

After new flywheel key installed and retimed my points/ignition

Got the engine to start 2nd pull but was rough. Ran for about 10 seconds and died.
Same again 2nd time around.

Then I lost spark. Tried a few spark plugs just to make sure it wasn’t a damaged plug. Same issue across the board.
Hoping my ignition coil hasn’t come loose or damaged. Took it half apart again but didn’t have time to finish today. Hopefully it’s just a loose coil.

What new coil did you buy and how were you testing the original coil?

Bought one off eBay.

Roughly $20.

To test it I used a multimeter. There are plenty of videos online to find out to test it and ensure it can be used.