Ford NAA locked up, Ideas?

[Verticaltrx]

I shut off my '53 NAA this evening for a couple minutes and when I went to restart it the solenoid just clicked. Tractor had only been run a couple minutes (backing load of corn in the barn) so it wasn't hot or anything. Tried to restart it a couple more times and same thing. Then held the starter button and herd a very slight humming in the starter and the wires began to get hot, as if it were trying to turn over but couldn't. Decided to try to roll start it and went down a good hill trying it in every gear, but the rear tires would just lock up every time I let out the clutch. That's when I decided the motor must have somehow locked up.

Not sure what happened as it has been running perfectly, full of oil, and was reading about 5-10psi hot idle oil pressure, and 35psi hot at 1500rpms last time I used it. Only odd thing the tractor has ever done was it would lose oil pressure when going downhill on any decent slope, as soon as you turned across the hill or leveled out oil pressure would come back. Going uphill it would keep oil pressure. Not sure if something was funny about the oil pickup and it finally let go or what. This tractor could have 2000hrs on it or 20,000 for all I know. It has been 'rebuilt' at least once, and who ever did it didn't do a good job. My first project was replacing the rear main oil seal as the P/O put it in backwards. So who knows what is going on in there. Any ideas on what could have happen all the sudden would be great.

 

[LD1]

I dont have any Ideas off the top of my head.

But I will say, dont rely only on the "roll starting" method.

Get a wrench and put on the front of the crank to verify weather it is locked up or not.

 

[Verticaltrx]

I dont have any Ideas off the top of my head.

But I will say, dont rely only on the "roll starting" method.

Get a wrench and put on the front of the crank to verify weather it is locked up or not.

True, but it has always roll started whenever I've tried before. These motors are very low compression and pretty easy to crank over that way. I'll try to get something on the end of the crank, not sure what as it has a little pump drive coupler on the end.

 

[Soundguy]

1, pull spark plugs and see if it is hydro locked.

2, 5-10 psi hot idle? on a red tiger? AND it looses pressure when moving on a grade?

that oil pump or pickup, or engine is seriously SICK.. even the most claptrap red tigers usually hold 25 psi hot idle... i'd be looking into that immediatly.


soundguy

 

[Verticaltrx]

1, pull spark plugs and see if it is hydro locked.

2, 5-10 psi hot idle? on a red tiger? AND it looses pressure when moving on a grade?

that oil pump or pickup, or engine is seriously SICK.. even the most claptrap red tigers usually hold 25 psi hot idle... i'd be looking into that immediatly.


soundguy

I went out a few minutes ago and put a 2ft bar on the crank and it wouldn't budge, it's locked up tight.

I'll try pulling the plugs, but not sure why it would be hydro locked.

It's looking like a complete rebuild is going to have to take place, so the oiling issue should be evident when I tear it apart. Still unsure why it just locked up out of the blue, maybe the oil pickup came out of the pump or something. The only visible problem is the bottom of the oil pan had been pushed up a little at some point (before I got it), but when I had the pan off to replace the rear main seal I made sure it still had adequate clearance. Also made sure the oil pickup screen was clean, which it was.

 

[Soundguy]

I'll try pulling the plugs, but not sure why it would be hydro locked.

.

not sure why?

you don't suppose there is a couple gallons of liquid coolant circulating in the block do you? and a fibre/paper/metal/composite gasket is keeping the water out of important places like... combustion cylinders? I've seen a running engine be shut down, have a spontanious head gasket leak filling a jug, and hydrolocking it... I've also seen one fail from lack of lube and have the bearing shells weld to the crank.

5 psi of oil pressure on a red tiger would scare me to death.

I've colelcted a pretty good deal of junk over the years. i have some red tigers that are so loose you coul push start them by hand and the valve train rattles like a.. well.. train, and smoking more from the breather than the muffler.. and still hold 25 psi hot oil pressure on 15 yer old 10w30 oil...

then red tigers had awesome lube setup.. a unit in any condition above poor usually starts at cold idle with 50+ psi oil pressure, and can maintain it hot if in good condition.

either the important engine clearances are wadeenough to drive a bus thru, or the oil pump is seriously worn, it's sucking air, has very low oil, or is running on mostly gas in the crankcase with some oil mixed in it to give it a dark color...

if pulling the spark plugs does not show hydro lock,, i'd be dropping the pan and looking at bearingcaps.. hot ones will liekly have turned color.... might even have spun a bearing, depending on if you used to have good oil pressure, and it suddenly changed.. etc..

for the heck of it, pull the hyd plug on the small option cover under the rigth fornt of the seat, in case some weird failure in the unloding valve is blocking flow and you are pumping against the relief.. and it's stuck .....somehow..

soundguy

 

[Verticaltrx]

Thanks for the info.

As I mentioned before, motor was 'rebuilt' by a real shade tree mechanic, so really any of the above could be the culprit.

I'll also add, when I had the pan off to change the rear main seal, I checked the main bearings and they looked almost new. Plastigage'd them and they were pretty close to spec on the clearances. What was seriously disconcerting was the fact that the crank had so much end play that when you push in the clutch you heard a thud. That was the crank moving forward about a 1/4"

The thrust face on the mains looked to be in decent condition, but the crank itself had a groove worn into it where the bearings ride against it. So when I do rebuild I'm going to have to either buy a new crank or have that one built up an machined.

I guess I need to to a little more investigation first, but it is sure seeming like a full motor rebuild is eminent. I was hoping to get a few more years out of this tractor before that was the case, as my plan was to do a FULL rebuild on the tractor when I do. I mean take the entire thing down to bare castings front to rear and rebuild/refurbish everything like N-complete does. Problem is I really don't have the time to do that right now.

 

[Soundguy]

i'd think it for sure has some thrust issues.. and if it really was a rebuild.. it should have had new, not nearly new bearing shells.

sounds like they took it apart and put it back together, vs rebuilding.

good luck on her.

soundguy

 

[NormL]

Way back in the day, when I was still a little squirt:laughing::laughing:, I remember starters "hanging up". That meant the starter drive had jammed up tooth on tooth on the ring gear. Before you put the wrenches to something else, try loosening the starter first. It's worth a shot.

 

[Soundguy]

his bar over should have made it move if it was hung. it don't hurt to check.. but i doubt he's that lucky on this one.

soundguy