Does anyone know the percent likelihood that any of these irrigation units would actually be elusive 427 centeroilers? There are FE legends that a rare few were 427 cubic inch with 4.23" bores.

Wouldn't it be fun to purchase one of these engine units and win the 427 industrial engine lottery? 427 industrial motors are a real thing, but aren't they considered a fluke unicorn in irrigation motor applications?

Clark Coe

As mentioned by thatdarncat, Ford factory production I.D. metal tags can be sometimes found under the bolt securing the ignition coil to the intake manifold. This would/could suggest an engine that is a factory "virgin"....never been disassembled/repaired/rebuilt. These tags are often covered with a thick layer of grease and not visible.



The cubic inch size is in the top left corner. Model Year is top center. Year of engine production is in the lower left corner, "A"=January, "D"=April and "E"=May.
Change level is upper right. Engine code number is lower right.

As they say on TV, "Your results may be differ."

Clark

Found my vibration and the source of the 2000 rpm cabin noise!   

This is from an assessment by running the Mustang in the garage. There is too much embedded salt dust in Nebraska's roadways and a few snow piles still melting into the street, so I did not take it out for a drive.
After removing the interference between the transmission case and cross-member, the maddening vibration/sound is gone. Plus, the Mustang now has an updated ignition system. Another plus is the faint gear whirling noise at idle with the clutch out, that could be heard in the cabin is gone.

You could feel and maybe more hear something was off. And it nagged at me....At a certain RPM it would do this thing . Not a shake so much as a sound and feeling that something was off... After going over and over and over this thing on the lift about a million times I finally found that in the impact the trans mount had a sort of limiter inside of the rubber isolator that got bent and it was touching metal. So it doesnt take much to get what you are describing....

Blueoval77, Thank you for sharing your Subura story. That was great motivation for me to keep looking.


This clearance crack required alot of time with a 7" disc grinder. Had to weld the opposite side of the bracket because this clearance removed all of the origin welds. Will need to repaint it.

Great example of how Jay's Forum has allowed a ton of replies, all in the spirit of helping out another member, eh?

machoneman: Isn't that the truth! I am so appreciative of everyone here on Jay's forum that commented and contributed to finding a remedy to this vibration.
Thank you all.

Clark

I did a lot of NVH work at Ford.  ANY metal-metal contact with a powertrain component will cause booming in the cabin and drive you nuts.  That TKO conversion has me wondering if you've got a clearance issue in the tunnel.  Maybe the trans mount is twisted or hard against a stop?

Bill, I think I am on to something concerning the annoying drumming sound in my Mustang cabin. Thanks for encouraging me to take a second look. When I completed the TKO conversion, I was careful with the clearance and fit in the tunnel area. Even with the optional cut-down case, a few well-placed hammer blows were required. Did not look that close at the trans mount area.

Today I pulled out a untried, Holley 4150 1850-2 from under the bench. It already had a fresh renew kit in it, but I have never run it on any engine. Took a couple hours to work out some bugs and install it on my 390. Anyway, the vibration and cabin sound remained at 1950 rpm - 2200 rpm range. However, this carburetor did not dribble as much at 2000 rpm.

Turned the idle up to 2000 rpm, slid under the car and held my hands on the underside of the tunnel. It was really vibrating.

While I was lying on concrete, on my back and trying not to burn myself on the exhaust, inspected the TKO transmission mount. Thought this looked suspicious


Took a break to allow the exhaust to cool, moved the Mustang to the middle of the garage and put it up on four jack stands. Removed the transmission mount and found a contact mark where the transmission case and the mount were touching. Those are not cracks in the transmission case, just casting parting lines and a scratch in the aluminum.





By now, it was time to grill some pork tenderloins, enjoy a Shiner beer and have some supper with my wife.

Tomorrow, I will get out my trusty grinder and create some clearance between the trans case and the mount.

Once again, I really appreciate everyone's input.

Clark

A couple of things.

1 - Compression check is smart, doesn't hurt to know what you are seeing even if it is good
2 - Do you have any valve train noise when the shake starts?
3 - Have you looked at the advance curve as it comes in?  Might be hard to do with one person, but it should be consistent with RPM, if it jumps, maybe the advance weights are sticking and its retarded then releases.  You could add 10 degrees initial after it starts (can't really drive it that way, but if it changes it tells you something.  No load it'll be fine)
4 - Could you record a movie of the exhaust when it's in the shake?
5 - When it is hot, and the choke is open, if you cup your hands over the carb, does it rev up slightly before it chokes? (Don't use the choke plate, use your hands, watch your jacket and hoodie for the fan etc)

After that,  likely smart to bolt on either a 600 I have or a 3310 and see what it does.  I am working out my schedule, sorry I vanished, we can likely get together soon if you don't figure it out

Ross, here are some answers:

1.) I have completed a dynamic, running compression test and here are the results. Static compression looks good for 9.5 CR pistons. All of the 3000 snap readings are too high, suggesting some restriction in the exhaust system. What next? My Mustang has a complete, stock exhaust system, complete with twin exhaust resonators and crossover muffler behind the rear axle. Remove the muffler?

 (This running test consumed three Schrader valves. The valves have a limit of how much pounding they will tolerate. Tried removing the Schrader valve, but the gauge was too difficult to read.)


2.) Valve train makes no odd noises. Have Pumpbuilder rocker spacers and end stands. Have adjustable, factory rocker arms.

3.) Mechanical advance starts to move at 1750 rpm, then moves smoothly for 21 degrees to be fully advanced at 3000 rpm. I adjusted the initial to 24 degrees and that did not make a difference in the vibration.

4.) I do not know how to post videos of my exhaust? Will Postimages.com host videos?

5.) Clamping my hand on the carb inlet chokes out the engine without any rise in speed....no vacuum leaks.

Was the Torino that you pulled the engine from crashed? If not, did you drive it b4 pulling it, noticing any vibration? You had this vibration from day one of the rebuild? I had a 289 that I went through with this. Pulled it from a crashed Mustang that was hit hard and low in the front. I just put up with it until one day a rod nut vibrated loose and it puked it's cookies. I too had changed transmission, clutch & flywheel to no avail.

Shady: In 1980, I bought the 1968 GT Torino for $50, drove it home and removed the motor. The Torino was not wrecked and I do not recall any clues of substantial body or frame damage. It was a very odd Jade Green Torino, GT option with 2V-premium gas 390, three on the tree, AC, bench seat and a open rear differential.

Yesterday afternoon, I installed a Pertronix II ignition module and the supporting Flame-Thrower II ignition coil. This did not make the 2000 rpm shake disappear, but the engine seems to start a little easier and settle to an 700 rpm idle sooner. Measured the voltage at the + terminal on the coil and got 11.98 VOLTS. Guess the resistor wire does not work, I was expecting 9 volts.


What to check next? At 2000 rpm, the ignition advance is 27 degrees, does that seem correct? At 2000 rpm, fuel is dribbling out of the primary boosters, looks kind of sloppy as it piddles out. Should the carburetor be metering the fuel from the boosters at this time?

The primary jets are #66. Would trying #68 jets be the correct direction?…richens the mixture a little bit for the single plane Streetmaster intake?

Thanks for everyone’s input and suggestions. Remember, it’s Valentine’s Day….hug your honey!   

Clark

I didn't notice it, but have you put an dial indicator on the flywheel/crankshaft assy?
(I.E. is it concentric and square? I have had one engine where the crankshaft flange was not true. The man that balanced the rotating assy caught it. I remachined the flange in the lathe, it was out about .005" which is magnified at the flywheel rim!)

Using a dial indicator, I measured .008” of Flywheel Clutch Face Runout. This was measured at the very outside diameter of the McLeod flywheel. While .008” is not a great value, it is inside of the Ford specification of .010” maximum.