1712 just stopped while mowing?
 

Last night I wascutting grass with my new to me 1712 hydro. I was at 3/4 throttle and while mowing the motor just stopped and will not start. What could cause this? I pulled the plugs. They one was black, one was white. They were not wet. I pulled the air filter, and while cranking it over, it seems to blow fuel back through the carb. I cant seem to get her to start.. Any advice or help? Please.

For starters, why are you mowing at 3/4 throttle? Air-cooled engines need to be run at wide-open throttle under load to cool them properly.

Three things are needed for the engine to run: spark, compression, and fuel, and they all must be present at the proper time. You haven't given us too much to work with, so check for those things first.

Matt324

Pull the plugs and see if you have spark. What do you have for an engine?
From the little bit of info you gave us I'm guessing that you have some sort of electrical problem. If you have a KT Matt G knows what to look for.

The 1712 should have a KT-17 Series II in it.

Ok guys sorry for not being descriptive enough, i was in a panic. So i snuck some time at work to research the websight threads.. Im at a stands still. Tonight i put in two new autolite A26's in each cylinder. And to no avail. Let me tell u the whole story.
My 1980 IH cub 782 went down at 1683.5hrs last saturday.. No more horsepower.
So i bought a clean 1712 off a local guy on clist last wed that was his grandpas.
I mowed .61acres 3 times and after the inital oil change it was 1/3qt low.. No biggie.
It has the KT17 series II with 803.6hrs and there is slight oil on the bottom air filter holder.
My wife was mowing yesterday and i get the call.."the mower just quit all of the sudden".
My heart dropped.
So it was on ADD when she checked the oil. She added it to the FULL level on the dipstick. Still wouldnt start. Gas tank is full. So last night i cranked and cranked to no results..

So tonight while cranking, there is raw/burnt fuel poping out of the top of the carb. I have the air filter pullled off. The plugs are firing, it acta like it wants to start, but coughs.. Anyone with any thouhts? Advice?

You still haven't told us whether it has compression or is getting gas in the cylinders.

Charge the battery so that you can crank it over fast enough to get a good compression test. Take the spark plugs out, screw the compression tester in and crank it over with the throttle wide open. Let us know what you get in each cylinder. If you don't have a tester go to an auto parts store and get one, make sure you get one that matchs your plug thread size. Have them explain to you how to use it if you don't know.
Is the gas old? Are you sure it was only down to the add mark when the wife filled it? Did someone maybe put something other than gas in it, maybe kero? When you said one plug is white and one is black that's telling me something is not right, they should be the same color. Just gonna toss this one out if your other Cub went down "No power" and now this one quits did we fill both with some bad or wrong fuel out of the same can? Something strange is going on.

I checked the compression tonight. Drivers side 0psi, passenger side 55-60psi. Not good. What to do next? is it better to reman or buy a briggs vanguard kit from smallenginewharehouse? Would rings and a gone be better? How can a motor with 804hrs go from strong running with lotsa power to blown up in a matter of 5hrs? I need help.

Matt

Hard to say what happened without seeing it apart. I know it sucks to have one blow but it is a 20 something year old tractor with 800 + hours on it. If the tractor is in good shape otherwise I'd repower it and you should be good for many more years. What happened to your other tractor?

The other tractor is a red 782 with no power. It uses oil and struggles to mow. Im was planning on tearing it down and repaint repower this comming winter. All new seals bearings ect ect..

The combination of running it low on oil and mowing at less than full throttle probably didn't do it any good.

You can rebuild the engine for less money than you can buy a new engine. Take it apart and determine the extent of the damage.

I agree.....:IH Trusted Hand:

It sounds like you're floating the intake valve - no compression and pushing air back into the carb. Maybe you stuck a lifter.

324Matt

Found this engine on Craigs list. Don't know anything about it but maybe it can get you going.

http://charlotte.craigslist.org/bar/2908352270.html

Thanks for the help about the ad on craigslist, but i live near st. Louis MO. Kinda too far for me. I think a lifter sounds right. Tonight I am going to tear into it. Pull the motor out and tear it down to find out. I have never rebuilt a small motor like this. Dosent look too dificult. I will post pics after i fix the computer cord my dog ate....lol

Maybe you can make one good engine out of the two you have. Not sure but I think both tractors have the same engine.

There is not a lot interchangeable between a Series I and a Series II, and nothing that'd likely break during an engine failure for sure.

I was able to do a complete rebuild on the KT17 in my 782 for around $500 in parts and machine work. (Doing all the labor myself) This included having the jugs bored oversize, new pistons, rings, rods, gaskets, seals, valve job, etc.

Ok, the motor is out and on the workbench. Pulled the heads and WHA LA! A valve that wouldnt go back down. I pulled the spring cover and there is a broken valve spring retainer. The cylinder walls have oil in them but not much more than .010. I ordered a Vanguard 18hp drop in motor today. This KT 17 series 2 is going to the shop for a hone and some new rings and pistons and a crank polish and a hot dip on the block. A friend of mine owns a machine shop (im fortunate). So, thanks for all the help guys. And whoever guessed a stuck valve is Winner Winner Chicken Dinner!

Sounds like you are going to ride again! Keep us up to date and WE WANT PICTURES! :biggrin2:

Great news!

I believe Sam meant

:TTWWP:


:biggrin2:

Well said, Sam!

here are the pics as promised.

and more with the old tired 782

Matt

2 things to make life easier on you. Remove the hood and grill only held on by 4 bolts that you get at from the front corners on the underside. 1/2 socket with a short extension. Other thing is the motor plate is held in with 6 bolts that you can get at from the underside also 9/16 socket for the 4 that are behind the axle and a 9/16 box or 9/16 ratchet box wrench for the 2 that are over the axel. I find it easier to pull the engine with the plate bolted to it.

You have some nice cubs, Matt!

And thanks for the pics too!

A good mystery
 

This was better than a "Murder she wrote"! We got the death and the police work and then the solution to the who done it. Can't ask for anything better than that except pictures and we got those too. What a great forum. BTW, what are you going to do with the KT after you rebuild it if you have bought a new Vanguard?

blowing back thru the carb indicates a intake valve failure most likely, pull the head on the side with no comp and look at them. I have also seen them blocked open be a chunk of carbon that broke loose. good luck with it. jeff
ooops, what I get for not reading all the pages before I answer. glad you found the prob.

Ok. Since the kt series 2 from the 1712 is rebuildable, i am going to rebuild it and add a oill filter and put it into the 782 after it is torn down and painted. The 1712 is going to be the work horse and the 782 will be for show.

On another note. The vanguard will he here today, so if anyone knows where i can start a build thread, i will post one up.

I have to go to florida for a wedding so no progress will be made untill monday night.!

Matt

I'd just continue this post. Then you will have the begining to the end.