Threaded hole on right side of engine block...

Chuck Christensen (MAFCA's Technical Chairman) sent me the following Email:

Steve,

In your studies of the Model A engine block, have you determined the original reason for the small threaded hole at the base of the right side of the block below the carburetor?

Chuck Christensen

Does anyone have any FORD data telling us just what the EXACT reason for that hole, which had an 1/8 x 5/16 headless slotted pipe plug (brass) (December 1, 1929 Parts Price List), was?

The Part Releases in relation to the Cylinder Block tells us nothing.

There are lots of "hear-say" reasons for the hole but nothing exact.

Thanks.

Pluck
 
Must have been for after-market oil guage.Henry was pretty frugal and didnt put anything more on the car than was esential.
 
Isn't that hole for a screw to hold the oil pump from sliding out. because if the spring breakes the pump would just slide down and would not pump oil. i havent walked out side to look at any of mine but just guessing.
 
Isn't that hole for a screw to hold the oil pump from sliding out. because if the spring breakes the pump would just slide down and would not pump oil. i havent walked out side to look at any of mine but just guessing.

Yes, it's a 1/8" pipe plug into the oil pump pressure passage and it's where you can hook up an oil gauge. You can screw a special tool into it to keep the oil pump in place while removing or installing the pan. You can buy the tool or make one by running a 1/8" pipe die on a 3/8" S.A.E bolt. Warning, after pan is on, remove the bolt and reinstall the plug, as it can put undue stress on the oil pump & could possibly seize the pump! I've never heard of the LARGE spring breaking that holds the oil pump up. IF THE SPRING EVER BROKE, THE PUMP COULD ONLY DROP BY A MINUTE AMOUNT.
Bill W.
 
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This doesn't answer Chuck Christensen's quest for actual Ford data, but here's my guess:

The freshly babbitted engines were 'run in' with an electric motor 'till the load dropped. Having access to that open side oil port would permit a quick fill of the valve chamber and dipper tray with a rubber tipped nozzle. No waiting for the pump to fill things at a critical break in point. With the pan plug also out, they could essentially be run in 'dry', with no oil in the bottom of the pan, the oil immediately draining. After the break-in they were probably tipped forward to empty the valve chamber and dipper tray, then both the side plug and pan plug would be installed. The engines were stored/shipped 'dry'. Cheap ole' Henry could probably run-in a hundred engines with the same gallon of oil.

Just my guess.
 
A friend in eastern Washington bought a '29 and a '30 and both had a pesky oil leak at the center of the R/H pan. BOTH cars had homemade lock bolts in that hole! Took them out, put 1/8" pipe plugs in, and voille', leaks GONE.---Bill W.
 
Simple way to keep oil pump from dropping is to screw in a common rad or block drain tap.When you turn the handle to open the tap,it should press againts the pump holding it in place.If by chance it doesnt just put a drop of solder on the end.
 
His question WAS answered! Why do we need so much "DATA" on such miniscule details that don't amount to a hill of beans??? I'll hush!--Bill W.
 
Hi Bill,
Yes it was answered but was it answered Correctly?????
It is a miniscule detail and some people live to find those answers.......Like an old Sherlock Holmes movie.....it is the HUNT that makes it worth while.
I really liked Mike K's answer as it does have some merit to pressure feed that inlet so the oil gets there imediately or before they even turn the drive motor on...Of course
That makes perfect sense.......and later on a port for a pressure gauge....maybe an after thought?
Ken
 
I've never heard of the LARGE spring breaking that holds the oil pump up. IF THE SPRING EVER BROKE, THE PUMP COULD ONLY DROP BY A MINUTE AMOUNT.

The one in my dad's car collapsed. He chased that noise for quite some time before pulling the pan down. The pump did not drop enough to render the it inoperable but the loose gear mesh must have been what was causing the noise.
 
But why should we beat a dead horse, over, and over, when the question has been answered, and it was such a simple answer! I'm surprised that a technical director for a major organization didn't know what the hole was for. Did he ever have a pan off a Model A, or did he never read any Ford repair books or vendors parts catalogs, which by the way have a lot of schematics and helpful advice. Yes, we probably all like to see our names on the Web and think we are smarter than the average bear! None of us know everything, but by pooling our knowledge, we can be an unbeatable source of knowledge. Yes, I add a little corny humor as I feel it will help someone remember a post with some very helpful information. I struggle with many problems in my life, and some mornings it's hard to get myself going emotionally and physically, while waiting for my pain pill to "kick" in, I read someone's car humor, life humor, or some enlightening repair info, etc, etc, and it REALLY helps make my day!! I trust that some of my "HUMOR" can help someones day, 'cause I'm sure some others are straddled with even more of life's problems than I have. I have a small family, so my local MAFCA chapter and you good folks are my EXTENDED FAMILY. I tell everyone I have "147 I.Q." and I write in a hokey down home manner as not to intimidate anyone.:D (I am really a backwoods old Okie boy, trained by "CHIEF," (my dad,) and have a knack for diagnosing and repairing these old crates into a very reliable operating piece of history. I'm a mediocre mechanic when actually wrenching, but I do know what makes them tick and how to diagnose and repair them.
If I'm offending any of y'all, P.M. me and lay it on me! :eek:Bill W.
 
I may be wrong but someone said something about filling the valve chamber to run the engines in. I believe I have read before that when the amps got below a certain point then the bearings were considered sized to 0 and a .001 shim was added. If this was the case then the oil pump and pan would not have been installed yet. A fitting installed in the port would allow a lubrication hookup for the break in.

This is an excellent question because millions of people have installed one of these plugs and it is the first time I have seen the question asked. It was used for other things but when you factor in that Ford would not drill a hole he did not have to it makes it interesting
 
It was use to locate / stabilize the core during the casting operation, threaded and plugged for final assembly.

Like how freeze plugs are really for the casting operation.

Just another thought.

GW
 
I've never heard of the LARGE spring breaking that holds the oil pump up. IF THE SPRING EVER BROKE, THE PUMP COULD ONLY DROP BY A MINUTE AMOUNT.
Bill W.

The Model A/Martin-Parry that I bought last year had a broken spring. I don't know why it broke, fatigue I guess. It still apparently ran OK, but I replaced it when I dropped the pan and cleaned out all the sludge.
 
Guys, may I again refer to the ORIGINAL question that I had asked...

Does anyone have any FORD data telling us just what the EXACT reason for that hole, which had an 1/8 x 5/16 headless slotted pipe plug (brass) (December 1, 1929 Parts Price List), was?


Looks like to me the answer is NO.

Pluck
 
I have seen pictures of production line running in stations, but I don't remember if "A", or V8, there was pipe from engines(it had a hand knob to install it) to gauges?? (small console) for each engine --perhaps the data you are looking for is hidden in the specs of the running in machines or procedures --it could be a dual purpose--first a fill to prime the valve chamber, then a pressure monitor to know the pump worked. ---I remember reading about the process, but don't remember where or when ----
 
To start with, I also agree that often time folks give redundant answers hours afterwards with the same information which I also find aggravating at times but maybe that is one of the reasons why this forum has such a good following as it allows many different folks to contribute where they feel they can. Therefore maybe it isn't that big of a deal.



Glen, to answer your question, Yes. Kurt I think that "console" is in the V-8 rebuilding manual?? With regard to the purpose of this port, I'm pretty sure we have had this discussion before on the old Fordbarn, and I think we even discussed this at one of the Fordbarn Workshops we held here at my shop several years ago. I will also say that I do not have a definitive answer for Steve either but I do want to point out some things that I have observed in researching something similar.

I have quite a bit of Model T information (like 800+ pages) that depicts very detailed operations and procedures for different assemblies of that vehicle. While the Model T was a totally different car, I do feel it does share many similarities with processes, procedures and tooling between the last years of the New Improved Car ('26/'27 T) and the A simply because of the short downtime while the transition was being made. One of the things I have been intrigued by is the assembly steps of how the engine was machined and then assembled, and even the time alloted for each worker to perform that specific task. Another one of the things that I have learned is that the picture(s) many of us have seen with the completely assembled engine & transmission installed on the Dynamo is not where I think the babbit burnishing was done as I have pictures showing it done earlier in the machining process. With several other theories of mine and studying those pictures, I am kinda of the opinion that oil was not used in the dynamo running operation either.

The other thing I am having trouble embracing is prelubing or filling the valve camber with oil through that port. If you think about it, the same limitation would be the end of the oil pump casting which would hinder flow. A much easier (i.e.: more cost efficient) place for machining and installation would have been on the valve chamber cover plate if that was his purpose for prelubrication. Also, why is it in that location instead of maybe moving it upward by 1.000" which would have eliminated that cause? I personally think the answer may lie in the drawings of the Oil Pan itself and the amount of revisions there are before the early pan with the clean-out/inspection cover. My theory is that initially the port was indeed placed on there as a way of holding the pump during pan installation prior to the pan with an oil pump access installed. Then maybe he decided that loading the pump from the bottom was a better idea after the pan was on. Many "wives tails" (← :D ) come along and I have heard that was a "cleanout" for the oil pan. Anyone that has 'played' long enough will tell you that even when that little plate is removed, it is very difficult (--if not impossible) to get all the sludge & debris out through that little hole. Therefore I am not so certain that was its intended purpose either.

What also makes me "buy into" my theory is because up until this engine design, he had never used a vehicle with an internal oil pump, and if you look at the design changes made during the first year or so, he changed the pump design a couple of times going from a forging to a cast housing, the shaft size was also changed, the valve chamber port & pipe location was changed, all as he was experimenting with oil management issues, --even through mid-1931. Since the Model T had many aftermarket oil pumps that were easily plumbed into the timing cover bolt to provide reliable oiling, he may have preserved this port just as a back-up in a different type was ever needed. Again, just theories based on many conversations of this subject during my past.

.
 
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