Hard Starting K-301 so Valve adjustment

[jsp_333 268]

I've got a k-301 0n a 312-8.  It has always been a hard starter.  Usually required a good shot of ether.

I didn't worry about it too much as  I didn't use it all that often but now  it wouldn't start at all.

Ignition module, battery, solenoid, starter all good.

I figured valve adjustment because I was running out of things to try.

Looked it up online and figured I could take a run at it.

Set the engine at top dead centre by watching the valves open and close (I didn't take the top of the engine off)

and adjusted intake to .009 and exhaust to .019 as per specs.

Now it won't turn over at all. Naturally.

 

Ideas for what to try next?  Does the engine have to be set at exactly TDC?

 

 

 

[lynnmor 7,305]

Select a valve and then turn the engine by hand till that valve opens all the way, then turn the engine one full turn and adjust that valve.  Repeat for the other valve.

[Skwerl58 704]

After adjusting the valves try  looking at the carb and spark plug. Most of my hard starting has been a spark plug or fuel issue. Install a new spark plug.  Adjust the carb by specs and make sure gas is there after setting and is getting there when turning over. New fuel line and filter and make sure the petcock at the tank is clear and tank is clean. Check to make certain the carb float is adjusted correctly and the carb jets are clean. You will figure it out after a little work.

[953 nut 55,222]

1 hour ago, jsp_333 said:

It has always been a hard starter.  Usually required a good shot of ether.

I didn't worry about it too much as  I didn't use it all that often but now  it wouldn't start at all

Any Wheel Horse with it's gas tank under the seat will eventually encounter hard starting problems. Even a new fuel pump is not too good at pulling fuel uphill. As the pumps age and the fuel system is exposed to contaminants the problems crop up. 

It is time for some deferred maintenance to be done. As @Skwerl58 said you should start at the fuel tank outlet and be sure fuel is able to flow. Replace the fuel hose and ad a filter to the system. You should now be able to have fuel flow to the inlet of the fuel pump. Remove the hose from the fuel pump to carb and crank the engine over to see if fuel is being pumped.

If you have been using gas with ethanol your fuel system probably is contaminated and the pump and carb need to be cleaned up. You can find stations selling non-ethanol gas on this site.  https://www.pure-gas.org/

[jsp_333 268]

Thanks All.  I'll start with lynnmor's comments and do the valves again using that technique.

 

I'm Using a spark plug from my everyday worker.  I'll do the carb to spec and if that doesn't do it I'll just replace it.

Fuel line and filter I can do obviously.  Only use non-ethenol gas.  I've checked the pump in the past and it's good.

 

I ended up at vales because the engine cranks a couple of turns then stops.  Then after a few second it starts to crank again. Sometimes it fired sometimes it didn't.   

[ri702bill 8,319]

Is the fuel pump losing prime while sitting?? The 312 has the gas tank under the seat like my C81 - I had the same hard starting problem. Added a 1/4" primer bulb - issue solved.

Over time, the OE fuel pump check valves accumulate crud that keeps them from doing the sealing job.....

Edited September 11 by ri702bill

[SylvanLakeWH 25,557]

 

Same on my C-105...

 

Couple squeezes of the bulb and fires up instantly...

[Ed Kennell 38,170]

1 hour ago, SylvanLakeWH said:

 

Same on my C-105...

 

Couple squeezes of the bulb and fires up instantly...

         Same on my 310, 312, and 520.    Save a battery and starter....install a primer bulb.

[Achto 27,571]

14 hours ago, jsp_333 said:

Set the engine at top dead centre by watching the valves open and close (I didn't take the top of the engine off)

and adjusted intake to .009 and exhaust to .019 as per specs.

Now it won't turn over at all.

 

If you set the exhaust valve while it was on the ACR (Automatic Compression Relief ) pin, then the ACR would no longer be doing it's job. This would cause your engine to turn over hard or stop when it hit the compression stroke.

 

If your engine has points, try static timing them. I have used this method to turn hard to start engines into 1 pull wonders.

https://www.mgonitzke.net/cubcadet/tools/static_timing.pdf

 

Edited September 11 by Achto

[Mike'sHorseBarn 2,998]

My c-161 takes FOREVER to start and it has the tank under the seat. I know the issue is the fuel pump losing prime, but I'm thinking about adding an electric fuel pump otherwise I'm afraid I'll burn the starter one of these days. 

[SylvanLakeWH 25,557]

35 minutes ago, Mike'sHorseBarn said:

My c-161 takes FOREVER to start and it has the tank under the seat. I know the issue is the fuel pump losing prime, but I'm thinking about adding an electric fuel pump otherwise I'm afraid I'll burn the starter one of these days. 

Two squeezes and she fires right up... 

 

[Ed Kennell 38,170]

55 minutes ago, Mike'sHorseBarn said:

My c-161 takes FOREVER to start and it has the tank under the seat. I know the issue is the fuel pump losing prime, but I'm thinking about adding an electric fuel pump otherwise I'm afraid I'll burn the starter one of these days. 

That also works.  Just be sure to remove the old pump and blank off the crankcase.   You don't want pressurized fuel leaking into the crankcase thru an old fuel pump diaphragm.

[jsp_333 268]

Going out to get a primer bulb this morning.  Interested to see if it solves the problem.  I'm still convinced it's valves but I've been wrong before.  A lot.

Acho I've been wondering about the ACR.

"This would cause your engine to turn over hard or stop when it hit the compression stroke. "  This is what I think is happening. 

But lowest hanging fruit first.

 

[lynnmor 7,305]

11 minutes ago, jsp_333 said:

Going out to get a primer bulb this morning.  Interested to see if it solves the problem.  I'm still convinced it's valves but I've been wrong before.  A lot.

Acho I've been wondering about the ACR.

"This would cause your engine to turn over hard or stop when it hit the compression stroke. "  This is what I think is happening. 

But lowest hanging fruit first.

 

When I suggested a method of valve adjustment I should have added that you need to turn the engine a bit in both directions to be sure that you are not on the compression release.  Just make sure that the lifter is on the base circle and not being pushed by the compression relief mechanism.

[jsp_333 268]

Primer bulb on order.

Double checked valve clearances as per Lynnmor. No luck

I've attached a brief video of what's happening.

Next is static timing.

 

[pfrederi 17,739]

Did you load test the battery????   Sounds like some of mine with old batteries...

 

Hook up you multimeter while cranking how low does it drop...

Edited September 11 by pfrederi

[jsp_333 268]

We have an expression in Canada goes something like this  FUUUUUUUUUUUUUCK!

New Battery. Fired right up.

Feel really embarrassed.  I've picked up 3 or 4 tractors this year and I guess a bad battery got in the 312.

Tested at 13 volts but dropped to 6 volts under load. This is what comes from being a cheap bastard and not getting a new battery immediately for any new-to-me tractor.

 

[pfrederi 17,739]

If you have 3 or 4 tractors it is well worth spending a few buck for one of these

 

 

[jsp_333 268]

pfrederi

yeah got one of those.  Just didn't check battery under load. The tractor I put the battery from the 312 in doesn't start now either.  Lesson learned.

[jsp_333 268]

On 9/11/2024 at 9:22 AM, SylvanLakeWH said:

Two squeezes and she fires right up... 

 

 

On 9/11/2024 at 5:19 AM, ri702bill said:

Is the fuel pump losing prime while sitting?? The 312 has the gas tank under the seat like my C81 - I had the same hard starting problem. Added a 1/4" primer bulb - issue solved.

Over time, the OE fuel pump check valves accumulate crud that keeps them from doing the sealing job.....

 

Update;

Tried to fire it yesterday and nothing. Gave up pissed off.

Then I remembered I hard installed the primer bulb. Went back outside,  couple a squeezes,  and she fired beautifully.  Again THANKS ALL.

[peter lena 8,625]

@jsp_333  agree with others on the  squeeze primer bulb , personally have added a , fuel check valve , vertically  just under carb , also have clear fuel line there , so I can verify  looking at fuel hold to carb set up .  pete