1993 Ford 1920 Engine Failure

[Mr Majestic]

Rebuild update...

It has taken quite a while but I finally got my 1920 back together this past weekend. After spinning the starter for about 10 seconds, she fired right up and the engine sounded great! Unfortunately, I ran into three problems that are pretty disappointing:

1) after starting it, I noticed the tractor/engine vibrates quite a bit and the vibration gets worse as I increase revs. At 1500 rpm, it was enough to convince me something is out of balance and I shouldn't rev it any faster. It's a low frequency heavy vibration. Though I never took the double-clutch apart during disassembly, and it worked fine before I took the tractor apart to fix the engine, I suspect the clutch might be causing the vibration. Though the clutch mounted back on just fine, I wasn't able to exactly duplicate the original mounting orientation because the alignment marks I made were gone after the engine was rebuilt/repainted. I also must admit I did not use the "Clutch Alignment Arbor - FNH 00078" during reassembly. I did use the input shaft for alignment and though it was good enough. I'm wondering if not using that tool may be causing the vibration problem or the clutch needs to be dial-indicated before tightening it??

2) secondly, the double-clutch doesn't actually work (disengage). When I depress the clutch pedal and try to put the transmission into a forward or reverse gear, the tractor moves forward or rearward as I'm trying to push the gear selector into a gear. Though the clutch pedal works smoothly, doesn't make any bad sounds and feels like I remember it...I cannot get the clutch to disengage. I can force the transmission lever into gear and the tractor will move but I cannot use the clutch to stop the tractor's forward/rearward movement...I need to force the transmission lever out of gear to stop the tractor...or use the brakes but doing so kills the engine. I have no idea why the clutch will not disengage.

3) thirdly, when I got the engine back from being rebuilt, the tech put a tag on two bolts located on the right side of the engine (see pic). The tag reads "must readjust to specs". I cannot for the life of me figure out what these two bolts do and their description/function is not listed in the Ford repair manual I bought for this rebuild project. Though I doubt these bolts are causing the vibration/clutch problems, I certainly want to figure out what their function is and how to adjust them.

There's a wealth of knowledge and experience on this site...I hoping someone has been though what I'm dealing with currently and can share some insight. Thanks in advance for any and all help.

MM

 

[90cummins]

Sorry to hear of your clutch problems, looks like you need to split the tractor again.
Hopefully the problem is obvious and inexpensive.
As for those two bolts they are for adjusting the injection pump.
One adjusts the engines high idle and the other adjusts the fuel rate (power).
After you get the clutch sorted out and can run it up to speed adjustments can be made.
NOTE!! I'm not sure which way the adjustment works but I suspect that turning them in will increase the engine speed and torque (HP).
I would adjust the speed screw first until it runs at the specified no load speed then slowly adjust the fuel (torque) screw until it performs as it did prior to the failure with no smoke.
90cummins

 

[pmsmechanic]

Here is my opinion for what it's worth.

In my experience there is nothing wrong with the way you installed your clutch. I have done it the same way several times. I have even installed single clutches without an arbor and just aligned them by centering the clutch visually or by feeling around the edge of the pressure plate and centering the clutch disc.

I once replaced a clutch where part of the lining had broken away and when the clutch was released it slipped in between the clutch disc and pressure plate. The clutch would not release when the clutch pedal was depressed. If this is your situation then it would also explain the unbalance in the engine.

 

[TractorTech]

As far as the vibration goes, it sounds like the rebuilder got the engine balancer out of time.
You didn't say, but did you try to adjusting the pedal? If so, no difference? I know you didn't disturb it when you took the engine out, but just curious.

 

[90cummins]

Good catch on the balance shaft TractorTech.
90cummins

 

[Mr Majestic]

Good insight gents, thanks.

Since the clutch is not working properly (won't disengage) and it only had 300 easy hours on it before the engine failed, I assumed it may be the cause of the vibration problem as well...thinking it may have been misaligned during reassembly (out of balance). Even if it's not the source of the vibration, I guess I still need to take it apart to see why it's not working. The balancer shaft (as a source of the vibration) is an interesting idea (thanks TractorTech). I wonder if that is something I can test/adjust/fix myself without removing the engine from the frame?? I'd hate to have to remove the engine and return it to the engine rebuilder if I can troubleshoot/fix it myself.

Any additional ideas or insight?

 

[Mr Majestic]

Also, thanks 90cummins for the info regarding the two bolts (used to adjust the injection pump). Anyone have further insight or factory paperwork/instructions regarding properly adjusting it?
Again, thanks everyone for your help.

MM

 

[Mr Majestic]

TractorTech, yes...I did try adjusting the clutch pedal linkage but it had no positive effect on the clutch issue.

 

[pmsmechanic]

The balancer should be timed to the crankshaft. If you can remove the oil pan without removing the engine it should be easy enough to see if the balancer is timed properly or not. Having a least an I&T manual for your tractor would show you what to look for.

 

[GPintheMitten]

Can't the engine rebuilder come out and check the vibration and balancer timing?