8N Noise, need opinions

bobsdaddy

New User
I Just purchased a 48 8N. I bought it knowing it had issues, the lady I bought it from said she thought it had thrown a rod. I finally got it started after rebuilding the distributor and it made a screeching noise like I have never heard. Extremely loud. When it first started it idled fine but applying power made it screech. There was no knock. I removed the belt to rule out the water pump or generator, but the screech continued. I drained the oil and cut the oil filter open, no metal anywhere. I am suspecting a rod bearing, and plan to drop the oil pan this weekend. Does anyone have any suggestions as to what they may think it is or know of anything that I should be looking for? Thanks in advance.
 
It will idle for 2 or 3 seconds then the screeching starts. It gets more intense with more throttle. It sounds like it's coming from the #2 or #3 cylinder area, but really hard to pinpoint. I dont want to run it to long like that without knowing what I'm dealing with. The lady I bought it from said she was brush hogging with it and it started out of the blue.
 
Is there any free play in the clutch pedal? If not, it's a good possibility that the throw out bearing is junk. I've had noises tranfer through a tractor so it sounds like it's coming from a totally different area. Check out everything before tearing it apart. What works good sometimes is a long screw driver. Put it against the tractor in different areas and put it up to your ear. It's helped me pinpoint many problems
 
(quoted from post at 17:07:21 08/13/19) Bob ,Does it have good oil pressure at idle?

I started and stopped it so fast I never checked. Pretty dumb on my part. I have drained all its fluids in anticipation of removing the front wheels and removing the oil pan. I think that I will replace the fluids and start it again so I can check the oil pressure and make a video so that all of you can hear it. Its hard to describe a noise. I really appreciate everyone's input on this
 

Hi. There is about 50% free play in the clutch pedal. I'm going to try and start it again tomorrow and video it so you guys can hear it.
 
Bob,If you have the oil drained out,Reach up into the drain hole and feel if the oil pickup tube is loose before putting the plug and oil back in it.But it sounds like it lost oil pressure and spun a rod bearing.Thus the squeaking sound.
 
(quoted from post at 18:36:33 08/13/19) Bob,If you have the oil drained out,Reach up into the drain hole and feel if the oil pickup tube is loose before putting the plug and oil back in it.But it sounds like it lost oil pressure and spun a rod bearing.Thus the squeaking sound.

I just checked the pickup tube. I can wiggle it a bit, not real bad but can move it maybe 1/8 th of an inch with no pressure put on it. I agree with the spun bearing theory. Can i roll new bearings in from underneath? I would like to get this tractor functional so that i can let my old 41 9n rest. I would like to restore the 9n first then move on to this one.
 
(quoted from post at 19:49:28 08/13/19)
I agree

For odd sound location a mechanics stethoscope can come in handy.

I had a squealing type sound coming from my 8N and with the stethoscope I zeroed in on it. It was the tach cable. Lubed it and it was ok.
 
Bobsdaddy,You ask,Can i roll new bearings in from underneath?
You could but if it has spun,but it would be a waste of time and money.
The bad rod would need replaced or resized,all of them at least resized and the crankshaft turned undersized.Do it right and don't waste your time and money just to be disappointed later.
I had bought a 2N not running like that once,that hat set for years.Got it home and as soon as I started it was squealing and had 0 oil pressure.It had spun #1 rod bearing before I acquired it,I could tell by the damage that was done
So fix it right the first time . :D
 
Probably not your problem but that year you have a front mount distributor and if the factory bolts to hold it on lose the lock washer when installing they will actually hit the timing gear and make a knock I have a 41 9N that had a knock and even mechanicks said bad wrist pin. Found out after tear down it had a 1" bolt substituted instead of the 3/4" bolt to hold distributor on and that was hitting the ribs on the gear. Simple check.
 

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