31707 0129 E1 Runs for a few seonds, then dies

[PTmowerMech]

Hey everyone. I've been out of sorts lately. Some medical issues (Back, knee and elbow) Still not back to up to par. But supervising my nephew on a problem he has.

It'll run for a few seconds. (30 sec. tops) then just die.
Spark test: When it dies, the crank is still turns enough rounds to see the spark tester lighting up until it comes to a dead stop.
Compression is good.
Good compression
New plug.
Snipped the fuel solenoid nipple.
Did a valve adjustment.
Fuel line, with new filter and shut off, fuel flows freely.

So the only thing left is the carb, right? I put a new carb on it last year. (A Stens carb).

 

[Born2Mow]

And did he leave ANY ethanol fuel in the fuel system over the winter ?

I suspect the old fuel has clogged the jets. The engine is cranking because the choke FORCES fuel up from the float bowl, but when the choke turns OFF (and they turn OFF fairly quickly) all fuel to the engine stops because the carb can't supply fuel through the usual passages.

I also highly suspect that that's what's wrong with the first carb.

You simply cannot not leave ANY ethanol fuel in a carburetor-type fuel system during storage. Even with a fuel stabilizer it's not a great idea.

 

[bertsmobile1]

Have you checked the timing key ?
Will it run for a full minute if you give it Short shots of carb cleaner down the throat ?

Sorry to hear you were down & out.
You have been missed
Glad to hear you are back upright again.
So what happened with the shop while you were ill ?

 

[PTmowerMech]

Have you checked the timing key ?
Will it run for a full minute if you give it Short shots of carb cleaner down the throat ?

Sorry to hear you were down & out.
You have been missed
Glad to hear you are back upright again.
So what happened with the shop while you were ill ?

I tried the carb spray on it today, And didn't get much more than a cough. Also watching the spark tester firing while it's turning over.

I haven't checked the timing key, simply because it sounds fine when it does run.
But now that you bring this up, I've adjusted the valves, but still get the slow to stop at the compression stroke. So I slowly turned the engine over by hand, and can see the ACR bump the valve. So I'll check that first thing tomorrow.

As far as the shop goes, I just stopped doing anything up there. I got to where I couldn't put my socks on. If I did, it was usually with my toes. Had to buy shoes without laces. I still have several probably a couple thousands $$$ in stens parts (and others) at the shop. I sure miss working from home. Being able to work at midnight if I couldn't sleep. Or lay down during the day when my back was hurting.

 

[PTmowerMech]

And did he leave ANY ethanol fuel in the fuel system over the winter ?

I suspect the old fuel has clogged the jets. The engine is cranking because the choke FORCES fuel up from the float bowl, but when the choke turns OFF (and they turn OFF fairly quickly) all fuel to the engine stops because the carb can't supply fuel through the usual passages.

I also highly suspect that that's what's wrong with the first carb.

You simply cannot not leave ANY ethanol fuel in a carburetor-type fuel system during storage. Even with a fuel stabilizer it's not a great idea.

I'm sure there was. And you may be right about it clogging something up. Except that even using carb spray, it won't start. By the time I started using it, the battery was drained, and having a hard times getting passed the compression stroke. So i put it the battery and my jumper on charge for the night.

 

[Born2Mow]

I'm sure there was. And you may be right about it clogging something up. Except that even using carb spray, it won't start.

Carb spray is not some kind of magic, wonder juice. It does NOT work miracles by being near the carb or sprayed into the carb.

You must completely disassemble the carb. When the carb is completely disassembled, and spread all over your work bench, THEN you can use it to spray down various holes and passageways in the carb body to check that the passageway is clear. Carb spray WILL NOT clear blockages, you have to do that with small wires and probes, such as dental tools.

ONCE compressed air can make it down ALL the passageways, THEN carb spray will finish the job by removing the varnish-like coatings and trash left behind that may still restrict the passageways.

Capish ?

 

[Scrubcadet10]

I think PT knows that.

 

[Born2Mow]

I think PT knows that.

Friend, I think you are assuming WAY too much.

He says he is 1) spraying the carb cleaner and 2) trying to start it. To me that says the carb is NOT disassembled.

If he'd like to share more detail I'm willing to listen. But until he does, that's my assessment. I only know what he tells me.

 

[Scrubcadet10]

I was thinking he was referring to Berts post about keeping it running with the parts cleaner.
didn't mean for that to come across in a condescending manner

 

[bertsmobile1]

I tried the carb spray on it today, And didn't get much more than a cough. Also watching the spark tester firing while it's turning over.

I haven't checked the timing key, simply because it sounds fine when it does run.
But now that you bring this up, I've adjusted the valves, but still get the slow to stop at the compression stroke. So I slowly turned the engine over by hand, and can see the ACR bump the valve. So I'll check that first thing tomorrow.

As far as the shop goes, I just stopped doing anything up there. I got to where I couldn't put my socks on. If I did, it was usually with my toes. Had to buy shoes without laces. I still have several probably a couple thousands $$$ in stens parts (and others) at the shop. I sure miss working from home. Being able to work at midnight if I couldn't sleep. Or lay down during the day when my back was hurting.

Sorry to hear that.
Know exactly where you are coming from
The RA that flared up last year had me crippled to the point that shoes were not an option. crawling to the dunny on all fours then having to run a hose through the bathroom window cause there was no way to use paper .
Glad to see you are back on your feet.
keep up the physio , I still can't feel tensions properly so the torque wrench gets used for everything , boy does that slow things down.
Was seriously looking at registering for the age pension , but that is behind me now ( hopefully ) and with some effort it will be behind you as well .
If you have not done so yet put a temporary ill health message on you phone.
I did and ended up having customers come in & pay me for supervising them fixing their own mowers & I sold down a lot of the inventory which I am slowly bringing back .

As for the engine , if the starter is hesitating then either the valves are too loose or the cam is worn down or the ACR is faulty .
That is always my quick & dirty test when servicing a mower, iff the starter hung or was pronounced lumpy then I did the valve lash.
When finished there was always at least 1 hour of mowing an if the starter hung after that the I knew there was a cam / head problem