been a long while, but need help, 312-8 won't run

[Jake0030 47]

Ran like a champ for an hour then died when a large stick bogged up the mowing deck. Removed said stick and nothing. She has gas, she has a fully charged battery. PTO not engaged, seat switch is engaged. Fuses and spark plug are good. This one is a mystery? She is trying hard to start,  but no dice, i just ware down the battery.  She turns over, but won't start. Any one care to take a guess?

Edited August 4, 2019 by Jake0030

[troutbum70 857]

If your sure it is getting gas and you got good spark from coil, my next thought would be a safety switch like maybe the one on the clutch or for some reason the one on pto shorted out and is disengaged.

[Jake0030 47]

I'm going to go over the beast tomorrow and try to figure it out. I'm pretty sure it's getting gas, maybe the carb is dirty, but she ran so well at first with no problems. I'll make sure gas is not the issue by unplugging the fuel line from the carb and pouring some gasoline in to fill it up. other than that, i'm assuming there is some relay that is not working? Thanks troutbum63!

[Yossarian 203]

I'd try a little (or a lot) of starting fluid in the carb.  I've had good luck chasing away small engine gremlins with that stuff and some seafoam.

 

ETA: I might be wrong but I would think a safety switch issue would prevent it from turning over.

Edited August 4, 2019 by Yossarian

[troutbum70 857]

While you have the gas line off at carb crank it over and make sure the fuel pump is spitting some out.

[Darb1964 1,014]

Starting fluid I don't know been the demise of many a small engine. The motor is dry already from cranking. Maybe flooded tomorrow it may start right up if the battery is fully charged.

[Yossarian 203]

15 minutes ago, Darb1964 said:

Starting fluid I don't know been the demise of many a small engine. The motor is dry already from cranking. Maybe flooded tomorrow it may start right up if the battery is fully charged.

If I've been doing it wrong, by all means let me know how and why.  Seriously not meant as an argument, just my own experience based on trial and error.  I've had really good luck with everything from mowers, tillers, chainsaws and blowers with the following procedures.  Drain all old gas, refill with non-ethanol gas and Seafoam mix according to (or kinda close, maybe a little extra)  Seafoam recommendations, apply starting fluid and crank engine. If it catches but dies right away I try again and spray fluid into the carb until it will run on it's own. Then I either let it sit and run for a while or use it until it runs straight.  Like I said that's just my experience based on a very small sample size. It doesn't address every issue but for me it has gotten things back on track for less than $10  and avoided busting any knuckles .  If there is any info on the how and why starting fluid is bad for small engines I'd love to hear about it, maybe in it's own thread though.

[Darb1964 1,014]

I love seafoam it is a great product and Starting fluid gets the engine started quick and then the seafoam cleans the carb.starting fluid dries out the cylinder and is very corrosive,if used alone or over many starts will score the cylinder. Starting alone is the most destructive time in a engines life. I like marvel oil ,add it to gas and oil helps I think  to protect the cylinder. Not trying to start an argument, if I came across like that I apologize. I would like to know what others think about Starting fluid I'm no expert that is for sure.

[gwest_ca-(File Mod) 10,495]

What is the model number and serial number of this 312-8? 

 

Starting fluid should only be used on engines that do not have a spark plug or a glow plug.

If used on an engine with a spark plug you stand a good chance of blowing the engine apart.

If used on an engine with a glow plug you stand a good chance of blowing your arm off.

 

Garry

[peter lena 8,064]

my first thought was this engine coming to a violent high speed stop with impact ?  i agree with DARB 1964, on the starting fluid issue , since regularly using  STABIL  in all of my gas , i have no fuel issues at all , i am thinking  that the heavy mower pull down  has caused a safety switch failure or related issue. i have also found the fuses near the lower battery tray can be an issue. replaced with a new fuse holder , fresh  fuses and dielectric grease on connections , eliminated issues , pete

[tunahead72 2,340]

11 hours ago, Jake0030 said:

I'm going to go over the beast tomorrow and try to figure it out...

 

I think that's your best bet, just take a slow careful look around the entire tractor and look for anything obviously wrong that might have been caused by hitting that stick.  Did you disengage the mower after this happened?  How big was this stick, and is it possible it might have hit any wiring, or fuel lines, or pretty much anything outside of the deck?  Look for disconnected wires, unattached hardware, anything unusual.  Take your time, and let us know what you see.

 

[troutbum70 857]

I agree with tunahead that abrupt shut down caused a failure that starting fluid is not going to solve. I would take a heavy wire strait from battery positive to solenoid or starter post and see if it will start, if so then you know problem is electrical. And if not electrical make sure fuel pump is squirting gas into carb, this is where a little squirt of starting fluid will let you know if it is lacking fuel if the fluid will get it to bark. Prolonged use of starting fluid is never good, I have used wd40 or similar in place of starting fluid as it does offer some lubrication so not to dry out seals and so on.

[Darb1964 1,014]

Thanks all some very good information as always. Very interested in the cause and cure

[troutbum70 857]

Hopefully he reports back with his findings.

[953 nut 51,656]

23 hours ago, troutbum63 said:

safety switch like maybe the one on the clutch

The clutch switch would keep it from turning over with the key, @Jake0030 said it is turning over.

If you take a slow system by system check of the engine you will find the problem. Do you have spark?   Is fuel coming out of the fuel pump? Will the engine fire with a bit of carburetor cleaner sprayed into the carb.?

[troutbum70 857]

Good point 953 I should have thought of that. That the clutch switch would prevent it from even turning over, another brain fart on my part.

[Yossarian 203]

2 hours ago, 953 nut said:

The clutch switch would keep it from turning over with the key, @Jake0030 said it is turning over.

If you take a slow system by system check of the engine you will find the problem. Do you have spark?   Is fuel coming out of the fuel pump? Will the engine fire with a bit of carburetor cleaner sprayed into the carb.?

That's kinda sorta pretty much what I said.  Is Carb cleaner that much safer/better than starting fluid?  Are there any safety switches that will let the engine turn over but not catch?

[Jake0030 47]

Hey everyone Thanks for all the info and advice. Sorry, I had bigger fish to fry yesterday as this city slicker is still learning to be country. Well pump pressure switch went out yesterday. Had to deal with that first. Now its the tractor's turn. I'll report back shortly.

 

[posifour11 723]

12 minutes ago, Jake0030 said:

Hey everyone Thanks for all the info and advice. Sorry, I had bigger fish to fry yesterday as this city slicker is still learning to be country. Well pump pressure switch went out yesterday. Had to deal with that first. Now its the tractor's turn. I'll report back shortly.

 

Wait til your controller burns out a condenser and you freak out thinking about needing a new pump. 

[troutbum70 857]

Confucius says a family without water is not a happy family. 

[Jake0030 47]

Late 80's model , i thought it had no fuel pump,  just a gravity fed carb. kohler engine. I know she has gas. The only thing i have noticed for the first time is audible clicking at ignition switch. Bypassed seat safety switch as it's the only one that has ever given me problems. I am certain she is getting gas to the carb, but have not removed carb to check for bogging. Next step i guess is to take the dash apart and start looking for something wrong. The stick was not that big, but thick enough to stop one of the blades. It did not make contact with frame, wires or mechanical parts other than the one blade on the deck. I have since removed the deck. I don't know guys, I'll keep at it.

 

Edited August 5, 2019 by Jake0030
incorrect data

[Jake0030 47]

Starter is not making any weird noise, but i took the spark plug out, it was dry and clean and there is no difference in operation if i remove the connection to spark plug.

[Lee1977 6,217]

I think you disloged some trash in the carburator that is causing it not to start.  If the spark plug is dry it's not getting gas.  You need to clean the carburator.

[clueless 2,898]

On 8/4/2019 at 5:34 AM, gwest_ca said:

What is the model number and serial number of this 312-8? 

 

Starting fluid should only be used on engines that do not have a spark plug or a glow plug.

If used on an engine with a spark plug you stand a good chance of blowing the engine apart.

If used on an engine with a glow plug you stand a good chance of blowing your arm off.

 

Garry

Carb cleaner will make it fire and is far easier on theses little engines. 

[953 nut 51,656]

1 hour ago, Jake0030 said:

Next step i guess is to take the dash apart and start looking for something wrong.

If the engine turns over with the key and you have spark I doubt that anything in the dash area is the problem.