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Just when you think all problems are solved... Just replaced the starter and turns over/cranks fine. Background, I had taken apart (I don't know much about engines but...) the Zenith carburetor about 6 mos ago cause it was running poorly. Checked the float valve and all seemed OK. Set the needle valve at recommended position. Overall there was an improvement. No problems but then after not using for many months started up one day then the next just getting solenoid click sound. Long story short finally put the starter armature on a growler and was deemed failing.

Got a starter replacement installed and started the tractor yesterday, pulled choke out like normal but engine just puttered and did not fully get going while I was tring different positions with the choke there was varying degrees of stronger turnover. Then I tried again with no choke and it started fully up. Dug my trench for a good 2-3 hours then shut it down for the day and refilled the hydraulic fluid (it leaks) and topped off the gas. Tractor is on a slight downhill slope. Today I can't get it started just sputtering. I pulled apart all the fuel lines, blew some/most out with compressed air. Fuel seems to be flowing. I'm thinking that my problem is a fuel related one.

Note: all pics were from before when carb was removed. Carb not removed now. There is a large screw (see white arrow pic) at the bottom of the carburetor, I don't know what it's for but I loosened it and gas began pouring out. Is it supposed to do that? or is there something wrong with my float? How can I tell if float and needle are working without taking carb off? Any tests I can do? Is it flooded? Thanks much!
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The bowl nut you have arrowed is a float bowl drain plug and yes fuel will run out when all connected up, you would use this to drain bad fuel if engine was running rough.
 

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I think it is about time you checked the actual spark for colour, pull the plug lead from any plug and connect to a plug that you removed and replaced, place the plug on a good earth point and have someone crank the engine while you check the spark at the plug electrodes, a blue spark is best, check the ignition points for correct gap and condition of contacts and the condenser, a crook condenser will do what you are experiencing, if you have badly arced contacts, then replace both contacts and condenser, with a good American or British made one.

An old saying, "if you think you have fuel problems, then it may be electrical", because both will give a similar problem and it is easier to check electrical before fuel.

If you can prime the fuel pump with the primer and you get good supply, then the diaphragm and the reed valves are ok, the long banana lever goes against the cam shaft and this gives the pumping action, you have to be sure when inserting the pump that the lever actually goes against the cam lobe, it is easy to place the lever on the wrong side of the cam lobe, that I know.
 

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I'm going to test the plugs tomorrow like you said. I reset all the new plug gaps to recommended .025 before I installed them. I believe the previous owner ( 6/2020) had recently replaced distributor, rotor and wires. I'll need to google about ignition point gaps, and condenser. My manual says "Distributor Gap : .014" But I'll need to go through it. Good point about fuel pump alignment with cam lobe. I had no idea and just shoved it in. I'll have to remove and try and make sure proper. When you describe "prime the fuel pump" and "you get good supply" can you expound on that?
My mechanical pump with hand primer has two hoses/tube going to it. One comes from my gas tank that passes through an in line filter, then goes to the pump. The other leave the pump and goes over to feed the carburetor. How specifically would I test as you described? Would I disconnect one of the lines somewhere, then hand prime and notice if adequate (?) flow/supply is generated?
Thanks!
Most pump levers had to be inserted through the opening and kept close to the inside of the engine housing, sometimes when the pump lever rested against the cam lobe, you have to push against the pump lever to insert the retaining studs.

To check the pump operation, remove the supply hose from the carby inlet and place into a container and pump the lever and watch the flow, if the flow is a good squirt, then the pump is ok, if only a dribble then possibly a reed valve is stuck, but don't go there yet, you can also hold a finger over the hose end and pump the lever to check pressure as you pump the lever, be careful, can be a bit messy with fuel spray, the fact that the diaphragm is not leaking fuel shows that the diaphragm is ok and the reed valves are also ok when the fuel pump is pumping, maybe I should have said "PRIME the CARBY", I was probably thinking Prime the fuel/injection pump on a diesel engine, sorry, and fuel pump supply is the amount of fuel being supplied to the carby from the pump.

If you are not sure of what I have written, then ask questions again, I'll be happy to answer.
 

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Yes!! lots of things turning when you crank an engine with the starter motor at flywheel attached to the crankshaft, which moves the the pistons to TDC and BTC in their sequence, the crankshaft drives the cam shaft through the timing gears at half time, the camshaft drives the distributor and the valve lifters in time with the pistons and also a mechanical fuel pump if fitted, so yes a lot of things happening in sequence, and the order has to be correct.
 

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What do you think ? Good enough flow? Thanks
That output is between good and bad, did you try the primer lever to see what the output was like?, did you pace a finger over the outlet house to feel the pump pulse and if the pulse could lift your finger and pass fuel through?.
 

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No. I fugured if the crankshaft was working the pump properly (my video) then I did not need to do hand primer lever. RE outlet hose, you mean the same end as I show in the vid before going into carby?
yes, -- and the fuel pump seems to be working, but I expected enough fuel to fill the end of the hose as it was ejected, and placing a finger over the end would let you feel how strong the pulse was.
 

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Thanks again for your time yesterday. I ended up ordering from Steiner (express delivery $$$) new set of points, condenser, rotor that looks identical to mine. And also a new 12v coil. Doing some further meter testing I see that my coil is reading about 3.5 ohms on the primary and 10.56 ohms on the secondary. From what I can tell those #'s sound fine. But it did have some oil in the distributor lead wire socket. Then put the condenser on the meter neg on the wire and pos on the casing. I got a reading that continually increased. I saw on YT that that might indicate it's good. Now I'm a bit worried that these are good. The rotor looked in decent shape. I did look more closely at the points and see some corrosion on each mating part. Could this cause a problem? I'm temped to file/sand off to a fresh surface and re-install and see if tractor has improvement in starting. Do you think it's worth the time or just wait for my new parts?

Additionally I see the specs on the new coil I'm getting is rated a bit lower than mine at 3.1/9.6K.Should that still be OK for my tractor? Thanks! View attachment 80282
No wonder the engine wouldn't start, thats the problem right there, see if you can clean up both contacts and give her a go, you will be able to file the faces, but the movable contact is fairly had it, you will need to replace the contact set and condenser.
 

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Automotive tire Wheel Tire Yellow Wood


Use the pipe wrench as a last resort, you will damage the hydraulic pump drive shaft, there are about 5 studs that hold the drive plate to the front pulley, use a tyre lever or large screw driver between the each stud and the drive hub and lever downwards, there should be a timing pointer on the other side and a timing mark on the crankshaft pulley, rotate the engine until the marks line up, this will have both #1 and #4 pistons at top dead center, set the contacts at just opening, we used a cigarette paper to feel the contacts opening.

The timing pointer on the timing case may have a few graduation marks, if so, you will need to rotate the pulley until the pulley mark aligns with the last mark on the timing pointer, this will give you top dead center for setting the contacts, and all of the rotation of the crankshaft pulley is done in a clockwise manner.

And then again, you may have the timing marks on the flywheel, in that case you may have to remove the starter to locate these or there may be a cover on the flywheel housing that you can shift to expose the markings.

So with that, this cowboy will leave you with that info and will ride off into the sunset.
 

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LOL. This is something I was always curious about. And now with some new engine learning going on and all. My exhaust manifold has always had this indentation/HOLE in it towards the top. Whereas in my manual it shows a picture with a solid section and some casted #'s. Does my manifold have a hole in it? It almost appears to be molded that way. But now, knowing more than I did a couple of weeks ago. Isn't this where the fuel/air mix gets sucked out of my carburetor then it gets distributed to each of the 4 cylinders? If this hole is not intended, couldn't this put a wrench, so to speak, in the whole fuel/air thing? My engine would always want to lose power when I would greatly increase the accelerator. How exactly does this manifold design supposed to function? Upper section for fuel/air distribution and side/lower for exhaust? Thanks! View attachment 80292 View attachment 80293 View attachment 80294
Organism Tints and shades Art Paint Rectangle



I thought I had better ride back and comment on your last photo of the manifold, if that is a hole where I have that blue pointer aimed at, then you have big trouble, that part of the exhaust manifold has had it, another reason your engine will be playing up with the exhaust gas heating the inlet manifold, (you can see the black soot mark going up the inlet manifold towards the carby and to the right in the photo) this will cause fuel evaporation and make the engine lose power as you commented on in a previous post.

I think you should begin to look for a replacement manifold, you may be able to get the old one repaired, you may be able to do a temporary repair with exhaust manifold gunk, but I can see a repair of the left hand end and the actual exhaust manifold section doesn't look that great overall, sorry for the bad news, something you didn't need to hear right now.

Yes you are correct with your question, the upper section is the inlet manifold where the engine draws in the fuel/air mixture to the cylinders, and the lower manifold is for the exhaust gases to leave the cylinders and be exhausted safely .

Something else to consider with that opening in the exhaust manifold, should the carby leak fuel there with the engine running, then you will have a fire that you most likely will not see if you are using the backhoe until it is too late to fight it, just a thought for you.
 

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Thanks for the info here, really appreciate it! Enjoy the ride!
Geez!!, disregard that post, well a certain amount of it, sorry what I wrote was for timing the distributor.

All you need to do to set the point gap is to set the cam lobe on the distributor shaft inline with the contact set rubbing block lifter and adjust the opening.
 

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Is there a way I can do a test to see if my carb float and needle is performing properly while it is still attached to my tractor?
Not really with a top mount float setup, some carbies had the float and inlet pivoting from the side of the float bowl and it was possible to check these with the air horn off, if the engine is running sweet initially, then the float is working ok, if the engine is blowing black smoke and running rough, then you have a flooding problem.

You mentioned before in a previous post that you were squeezing the viton on the float needle, is this tip doughy?, if it is, then you will need to replace, the tip has to be firm.
 
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