Hello Everyone –
First time poster. Thanks in advance for the advice and expertise of this forum.
I recently acquired a 1953 Ford NAA Jubilee that starts and runs well, hydraulics work. It has a 12 volt conversion. Its duty for the previous 25 years has been snow plowing on a short 200 foot driveway here in South East lower Michigan. It appears to have been maintained minimally, although the oil, coolant and gas tank are clean and clear.
The tractor has a slight knock, and this is the main reason for my post. But first some background.
I first did a compression test (dry) with the following results:
Cyl 1 = 112 psi
Cyl 2 = 100 psi
Cyl 3 = 107 psi
Cyl 4 = 107 psi
I thought these were positive test results.
The next thing I did was to adjust the valve lash. I was glad I did this because cyl #2 (I think) exhaust valve had little or no clearance. After this adjustment the knock was the same. The top end was quite clean with no noticeable sludge buildup.
At first this knock occurred only during cold start-up and disappeared after about 1 or 2 minutes. However, it now seems to knock all of the time unless the tractor is under some load. Please understand that I have not yet changed the oil and filter, but that the oil appears very clean and recently changed. Again the knock disappears under load or acceleration.
Here is a video of a cold start. Listen to the knock http://youtu.be/jmKAox7zbqg
Question 1: What do you think is causing this knock based on what you hear in the video? What is most likely? Could it be a clogged oil filter limiting the oil flow? Sticky tappet? Other? Those with sensitive and experienced ears please comment.
Question 2: Is this something that might be helped with the addition of an oil additive like Marvel Mystery Oil? Or a commercial product like Motor Flush? Or with a high zinc/phosphorous (ZDDP) oil? I don’t want to cause any damage, but of course I am looking for an easy fix! I am preparing to change oil and filter for the first time and I’m willing to try an additive or treatment that might free up something that is sticking. Any recommendations based on your experience?
I was hoping that just running the tractor would cause this knock to get better but it seems to be getting worse in that it does not go away after a minute or so. I also believe that the tractor has a stuck thermostat (stuck open) and is not coming up to full temperature, but I am not sure because the temp gage is not working. Planning to replace water pump and thermostat soon.
I am currently working my way through the ignition system, cooling system and air cleaner to get the tractor into reliable shape. Carb seems OK.
Question 3: What are the recommended oils for the transmission, hydraulics and rear end? GL-1 for all? UTF (not sure what that is)? GL-5 for rear end? Guidance please. I am planning to replace these before the winter sets in. I am planning to use this tractor for both winter and summer duties. Sorry I know this was covered in previous posts. From the FAQ section it appears I should flush gearboxes with diesel or kerosene when I replace these lubes? Or just drain and refill on a warm day? As I understand it I have separate reservoirs for trans, hydraulics and rear end on the NAA.
Thanks in advance for your advice all. I am becoming quite fond of this tractor as it seems reliable and strong. I want it to be reliable and healthy!
George
First time poster. Thanks in advance for the advice and expertise of this forum.
I recently acquired a 1953 Ford NAA Jubilee that starts and runs well, hydraulics work. It has a 12 volt conversion. Its duty for the previous 25 years has been snow plowing on a short 200 foot driveway here in South East lower Michigan. It appears to have been maintained minimally, although the oil, coolant and gas tank are clean and clear.
The tractor has a slight knock, and this is the main reason for my post. But first some background.
I first did a compression test (dry) with the following results:
Cyl 1 = 112 psi
Cyl 2 = 100 psi
Cyl 3 = 107 psi
Cyl 4 = 107 psi
I thought these were positive test results.
The next thing I did was to adjust the valve lash. I was glad I did this because cyl #2 (I think) exhaust valve had little or no clearance. After this adjustment the knock was the same. The top end was quite clean with no noticeable sludge buildup.
At first this knock occurred only during cold start-up and disappeared after about 1 or 2 minutes. However, it now seems to knock all of the time unless the tractor is under some load. Please understand that I have not yet changed the oil and filter, but that the oil appears very clean and recently changed. Again the knock disappears under load or acceleration.
Here is a video of a cold start. Listen to the knock http://youtu.be/jmKAox7zbqg
Question 1: What do you think is causing this knock based on what you hear in the video? What is most likely? Could it be a clogged oil filter limiting the oil flow? Sticky tappet? Other? Those with sensitive and experienced ears please comment.
Question 2: Is this something that might be helped with the addition of an oil additive like Marvel Mystery Oil? Or a commercial product like Motor Flush? Or with a high zinc/phosphorous (ZDDP) oil? I don’t want to cause any damage, but of course I am looking for an easy fix! I am preparing to change oil and filter for the first time and I’m willing to try an additive or treatment that might free up something that is sticking. Any recommendations based on your experience?
I was hoping that just running the tractor would cause this knock to get better but it seems to be getting worse in that it does not go away after a minute or so. I also believe that the tractor has a stuck thermostat (stuck open) and is not coming up to full temperature, but I am not sure because the temp gage is not working. Planning to replace water pump and thermostat soon.
I am currently working my way through the ignition system, cooling system and air cleaner to get the tractor into reliable shape. Carb seems OK.
Question 3: What are the recommended oils for the transmission, hydraulics and rear end? GL-1 for all? UTF (not sure what that is)? GL-5 for rear end? Guidance please. I am planning to replace these before the winter sets in. I am planning to use this tractor for both winter and summer duties. Sorry I know this was covered in previous posts. From the FAQ section it appears I should flush gearboxes with diesel or kerosene when I replace these lubes? Or just drain and refill on a warm day? As I understand it I have separate reservoirs for trans, hydraulics and rear end on the NAA.
Thanks in advance for your advice all. I am becoming quite fond of this tractor as it seems reliable and strong. I want it to be reliable and healthy!
George
