VCCA Home Forums TECHNICAL - GENERAL Radios, Tools, Accessories 1928 School is again in session!

Mr JYD. MR Mack will not admit it, but as well as he has done in his professional & retirement life, he of all folk's would know that with a coor's can or bottle and bailing wire! anything can be done!!! we should all be humble to have mack on our side!

N.J. I have to give the old mutt a bad time or he would think I didn't like him!

Gosh....golly. He must then really "HATE" me. Te he he.

You are invited to take a look HERE.

Please read the note. Thanks, and your coorporation would be appreciated.

Geeze, I don't drink coffee either and can't afford the angle iron so use a tape and chalk. First raise front tires off ground and put supports under axle so load is as close as possible to when vehicle is resting on its wheels. Make a mark on each tire with chalk on a groove on the tread. Measure with tape. Rotate both tires to as close to 1/2 turn as possible and remeasure with tape. The difference is the toe in or out.

Gene I used to do that bit with the mark on the tire with chalk when I had a Model A F**d, my brother still crawls around on the ground with a tape measure, but he also is restoring a F**D. But that was before I spent all that money seeking a B.S.in M.E. degree, and thought I may as well use all that knowledge like trigonametry, Geoametry and Arithmatick!, some how I avoided the Spelling part of the English classes.

Hey Macky Wacky! Ya, it's been obvious that you avoided several English classes during your past career! ha ha!

MrMack ,

Your comments are examples of good maintenance on the older vehicles.

RustyFender ,

I understand what you are saying; however if you go to a new set of teeth on the pitman arm shaft, theoretically that is back to factory specifications less the minor wear on the worm gear. As we have discovered there is no adjustment for mesh on these two gears.

N j horst ,

The steering box is to be filled with the 600-weight oil. Then the instructions say to replenish it ever 1000 miles. As the gearbox is notorious for leaks, I use both the oil and a combination of grease. They will mix to a certain extent and some of the resultant mix will remain in the gearbox.

Chevguroo ,

You are not the only one to use grease in the U-joint ball. Just as I use it in the steering box I also use the same combination in the U-joint. I have disassembled several gearboxes and U-joint balls to find a preponderance of grease as the major lubricant. I like your idea of the use of the “O” rings to help seal up the U-joint ball.

MrMack ,

Your method of checking the toe in has some merit. I should caution that you should repeat the process more than once to remove any error introduced by a bent or crooked wheel.

ChevyChip ,

Again this is a method of arriving at a solution to the toe in. I personally, would want the full weight of the car on the tires when the measurements are made, however your method is better than doing nothing.

If you wish to really spend some time at this project and achieve more accuracy, jack up one wheel, provide a steady rest and with a lead pencil, mark the tread as you slowly rotate the tire. Do the same procedure on the other side. With the weight of the car on the tires, make the measurements. After all, with a standard of 0 to 1/8 inch in toe in, how wide is a chalk mark?


Before we got sidetracked, we had almost finished the assembly stage on the engine. The distributor was installed temporally, only as a reference to run the spark plug wires and to complete the installation and adjustment of the spark adjustment all the way from the steering column to the distributor. In preparation for starting the engine we must prime the oil system. Now remove the distributor.



This is the view of the top of the drive to the oil pump. We need to fabricate a device to fit in the slot on the oil pump so we can artificially pump oil.



One solution is to take a short piece of steel gas line. Flatten the end with a hammer so it will fit in the slot on the oil pump. With a regular drill, and in a clockwise direction, we can operate the oil pump. With my assistant watching the dash oil pressure gage, and operating the hand drill at full speed, I could generate 27 pounds of indicated pressure. Knowing that all 4 oil troughs are empty and that although I am reusing the original oil filter, it had been drained, the pumping was to continue until these items were full. I ran the pump for several minutes to accomplish this mission. Key locations now had oil for operation, however this procedure does NOT provide for any oil in either the main bearing reservoirs or the cam bearing reservoirs. Neither does it place any oil up front on the timing gears.

Install the bearing washer on the oil pump shaft.



Install the distributor for preliminary attempts to start the engine. (We will skip this procedure for the time being as it will be a class by itself).



You are looking at the flexible heat pipe from the stove to the carburetor. If you look just below the cotter key you can see the opening in the flywheel housing used to view the mark on the flywheel.



With the air cleaner installed (yes, I know it is missing the decal which will be applied later) it is virtually impossible to see into the hole and view the timing mark.

EDITORIAL : As far as I can tell, there is only one vendor of exhaust systems for the Chevrolet 4-cylinders. NONE of them fit as was designed. Not only do they not fit, the workmanship is totally unacceptable. This subject has been broached with the vendor with no noticeable improvement in either quality or fit. When I restored my 1925 Roadster I was so frustrated I decided to build the entire system myself. See G&D for October 1983 for my article on the construction of this system.



This is the driver’s side of the engine and shows the connection of the other end of the heat tube attached to the intake of the carburetor. Don’t think this heat tube is not important. Remove, or let the tube become dislodged, and try to operate your car. Yes, it can be done, but not as smoothly as when the carburetor is getting a good shot of preheated air.

Next class will be the positioning of the distributor, timing and initial attempt to start the engine.

Mr Ray: I noticed that on the bottom of the vaccum tank you installed a petcock, inline to carb ? Was that for safety reason's ?

Hi n j,

The shut-off Cock is part number 114644. It is necessary to shut off the flow of fuel from the vacuum tank to the carburetor if this line must be disconnected in order to work on the carburetor. Without the shut-off, each time the line is disconnected you would drain all the fuel in both tanks inside the vacuum tank. If the carburetor were subsequently removed you would loose that fuel also. On a restart it would place a huge drain on the battery to turn the engine over enough to obtain sufficient fuel for starting.

Ray
2 points
1. I used to manufacture exhaust systems for all model 4 cyl. Chevs, they were a bit rough and ready but did the job. I sold about 400 over 10 years. These are now being manufactured by another bloke in the VVCAA (aust. vintage chev club)and his are A1, even better than they were new. (I have n.o.s systems for 27 and 28 models for comparison) However the exhausts in Australia are somewhat different, because of the right hand drive interference. My 28 2 door sedan that I imported from St. Paul Minneapolis has an exact (as close as I can get it) copy of the US 28 system. If there was enough interest I'm sure he'd be willing to make them for export to the US. The purchase price would be probably be a fraction over $100 US, however you would need to add shipping to the price.
For models other than 28 he would need US paterns.
Let me know if you want me to ask him. I had one enquiry before, but tooling for one system wasn't economical
I could email photos of a new system off the car, if that would help.

Point 2. I noticed in one of your photos that the fuel line from the vacuum tank sagged below the point where it inlets into the carburettor, it should gradually run downhill all the way, and (possibly) have a vibration loop in it. All the Chev 4's out here run the vibration loop in both the vacuum inlet and the fuel outlet.
Chris

Ray, I noticed the cotter pin secureing the flex intake tube in the air cleaner, is that a mod you put on, or what was original? My 28 has a set screw that threads in the carb inlet and interfers with the flex tube which also appears in your photo, I haven't noticed the air cleaner end,it was already there when I purchased the car, is this a mod, or original? Do you have a early photo of the configuration of the fuel lines (tank to carb) and (supply line to vacuum input)?

Mack,
The cotter pin is original on the stove end for the later 4 bangers as is the set screw in the inlet of the carb. Earlier carbs used the long cotter pin. Both my '19 and '20 use the cotter pin on the carburetor end.

Chevguroo ,

Too bad you are not still making exhaust systems and exporting them to the US. In my opinion all the systems from 1925-28 are incorrect on numerous points and craftsmanship is nonexistent. If you have a picture of a correct 1928 system, and can send it to me, I will post it for and example.

Your second point about the fuel lines.



This picture was posted to the forum in a different thread. With the picture, which is taken from my Dealer's Album , (and is of a closed car), and data from the Parts Price List, April 1, 1928, for the Series AB-1928, this discussion can be concluded. Part number 328980, Gas Line passenger cars (125 ½”), part number 352020 Vacuum tank suction line (from top of tank to intake manifold 13 ¾”), and finally, Part number 345157 Vacuum tank to carburetor tube 15 11/16”). These measurements allow the configuration in the picture and no other routing is available. Also, in answer to a previous question. In addition to a Shut-Off Cock at the bottom of the vacuum tank there is an additional Shut-Off Cock Part number 120900 located at the gas tank.

MrMack ,

The connections at each end of the heat tube are the approved methods. As to the picture, see above. If you are in reference to how my car was when received, you don’t want to know. When the class is over I will have a few comments about the overall vehicle.

ChevyChip ,

You are correct on all points.

No Ray, I wasn't reference your car when you received it, just that I purchased mine , and it was the first 4 cylinder I ever paid much attention to. Thanks for the pictures and info on the fuel lines, I didn't remember seeing it before. My car does have a glass settleing bowl AC fuel filter on the supply line before the vacuum tank and a small 5/16" needle type shutoff valve just below the vacuum tank on the line to the carb, I will re-arrange the lines for a more suitable configuration, and also leave the filter in place. The line from the tank has been spliced with a compression union and it is 5/16 copper tubing, is that the original size?

MrMack ,

You are correct in that the fuel line from the tank to the top of the vacuum tank is 5/16. As to the material? Won’t go there.

How come no one ask me what oil I used in the engine or how much? So before you do, here is the answer. I use multi-viscosity 10W-30 oil, and the basic fill for the 4-cylinder engine is 4 quarts. The oil filter was new, but has been on the engine while operating. Most of the oil was drained out during the disassembly, so ½ additional quarts were added for a total of 4 ½ quarts.

Attention! All students gather around as we have a mystery to solve. The engine has already been operated; in fact the car has been driven on short test drives. However, in our sequence of operations in this class the installation of the distributor and timing the engine would have been the next step. When I went to take the pictures of the distributor I realized that the distributor had been installed incorrectly.



This is a picture as installed. Note that the clips for the distributor cap are 90 degrees from the line of the engine. This puts the back clip between number 2 and 3 cylinder and as a result it is extremely difficult to get to. Obviously this is not the correct way to install the distributor. I decided it would only take a few minutes to correct this error and I could then take my pictures. To make a long story short there was no way I could install the distributor correctly. I checked the model number 635B and that is correct. I dug out some more distributors and found another identical, however another one was completely different, and all had the same model number 635B.

(NOTE: The decal on the air cleaner is incorrect. I will discuss the decal for the air cleaner and oil filter in a later class).



Observe these three distributors closely. Look where the data plate is located, check the grease fitting versus the ridge on the base, and check the location of the stud where the wire from the coil attaches. The two on the left are the same, however the one on the right is different. After much research it was discovered the one on the right is the only distributor that could be mounted as required. So, stop everything and let’s rebuild a correct distributor.



On all motors after number 3409976, except motors 3410801 to 3415520, and on approximately June 1927, a new semi-automatic distributor was introduced. This distributor was the Model 635B. With the point plate removed from the distributor you can observe the two spring loaded counterweights. When the speed of the engine exceeds 1000 RPM, or approximately 22 MPH, these counter weights move and can advance the timing as much as 20 additional degrees at 2400 RPM. This gives us a total of 45 degrees before top dead center.



When working on a distributor, or changing the points, inspect this special piece of insulation that is located on the contact post. It is a critical part of the operation of the distributor.




Here you see the points installed along with the rotor. At the lower right you can see how the special piece of insulation protects the spring on the points and prevents it from touching the distributor body, thereby, shorting out the points.



Distributor installed and timed. Now the clips for the cap are parallel to the engine and can easily be accessed for checking the points or making adjustments.

Stay with us class. Eventually we will cover the installation of the distributor, adjustment of the spark control, and timing.

HOMEWORK: What is the point setting (contact opening) on the AA & AB?

Page 185 of the repair manual states 0.020" to 0.025". It does not indicate a different value for AA series but I don't have the repair manual for 1927 to cross-check.

Anybody care to guess what happens if you install the spring-loaded counter weights incorrectly? I'm not afraid to admit I did this once. :rolleyes:

-R

Hello,
I agree with chevguru(Hi Chris !)about the exhaust systems being made by his friend.I asked him to make one for my '28 Truck,and even though he said he'd never had a request for a truck system,he said he would have a go at it.
From the 4 Cyl Master Parts Book,we deduced that the "AB","LO" and "LP" were all the same.I picked up the exhaust system as I needed it desperately to go on our clubs May Tour to Albury,in May 2002,and it fitted up perfectly.It even sounds better,just like a Chev 4 should.
So I can highly recommend the quality of these exhaust systems.As chevguru says,the maker would need sample systems for your left hand drive cars,as ours are different down under.

Ray
I have just had 10 days off and as for some reason I can't access this column from my home computer, I had to wait till I got back to work.
Had the 28 out on 3 occassions while I was off, good stuff, should do it more often.

Re the fuel line vibraration loops, I was informed by an old codger that they were put in as our real crappy roads, which most were not sealed in those days, caused these lines to vibrate so much that they broke. So it could be an Aussie thing. I'll stick to them as we use our Chevs still on these off the beaten track dirt roads quite often, and I had a vacuum wiper line break off my 34 at the manifold and burnt out 3 exhaust valves. I now also have a tap in the manifold to turn it off in case it happens again.

Re the exhaust systems, I can give you a photo of my home made 28 system, and will ask the bloke who is manufacturing them to see if he can give me some photos of his reproduction systems. I believe that the 28 system would be the only one different for the left hand drive configuration. I'll have to email the pictures to you for you to post
Chris

Ray
I spoke to Gary Graham, the bloke making the Chev 4 exhaust systems. He will gladly ship to US, is going to give me a number of photos of a 27 system, which we believe is the same as US 27's, and is endevouring to obtain shipping prices to US.

I tried to email you offline via the mail option at the bottom of the post, and it wouldn't let me. I will need to able to do this to send you the photos for posting.

Also I will need the actual lenght of a 28 hot box, as I made my LHD 28 system from the diagram in the Service News. I know everything is perfect, because it fits nicely, but had to guess the lenght of the hot box.

I will give Gary a LHD manifold and he will set it up on a 28 engine in a rolling chasis to make sure it fits perfectly before reproducing a LHD version They can be supplied with or without the optional tailpipe

He makes all Chev systems from 1916 to 1928

Hope all this helps
Chris

Hello students! Your last homework was to give the point setting and a reference. RustyFender gave a value of .020 to .025 inches. His reference is above. This homework was assigned for a purpose. The Repair Manual on page 185 gives the above value; page 227 gives .018 to .024, and the OM gives the value as .018 to .025. You would think they would have a ”˜company’ value and be consistent.

EXHAUST SYSTEM:

You can follow the discussion by WIZARDSMITH278 and chevyguroo above. I hope one of them sends me a picture of a correct 1928 system and if so I will post it. I measure the hot box at 6 ¼ X 3 in diameter. This is from a repo system and is subjective. If the price is completive I feel there is a market for correct exhaust systems for at least the 1925-28 models.

RIMS:

While the engine work has been progressing, other adventures are also taking place. All 5 rims on the car were the wrong size. (They were 2 ½ inches as measured across the inside of the rim. This made them Capital AA 1927 rims). A set of 5 correct rims of the proper size has been obtained, sand blasted and just returned from the cadmium platting shop.



This measurement is to be 3 inches for the 1928. The diameter is 22 ¼ from the extreme outer edges. The tire size is 30 X 4.50 straight side balloon. Modern size for the 1928 is 4.40/4.50X21.



Isn’t it neat to have something just like brand new? You can even read the JAXON imprinting on the rim.



And my heart really beats fast when I can find the almighty BOWTIE imprinted on the part. It just doesn’t get any better.

TIMING:

Let’s get started on the timing of this fully assembled engine. The basic instructions for the installation of the distributor and timing are contained in Chevrolet Service News July 1927 on page 27. However, you need a good understanding of the operation of the engine to follow those instructions.

If you remember when we were assembling the engine we left the crank at the position where the 25-degree mark was showing in the timing window. The CSN does not point this out, but the 25-degree mark can appear twice in a single rotation of the cam. And, we MUST have the correct one. The side covers are on the engine so we can’t observe the lifters, but we can remove the valve cover and observe the rocker arms. To check for the correct rotation of the 25 degree mark observe the location of the rocker arms for number 4 cylinder. Why number 4, because the grind on the 1928 cam is such that it is very difficult to determine if both valves are closed on number 1. If we look at number 4 one rocker arm is in a pronounced different position than the other rocker arm. This indicates that number 4 is NOT on the firing position, but number 1 then is. Check the arms on number 1 and they should be at the same elevation. We have now insured that the 25-degree mark and the firing of number 1 are coordinated.



Install the distributor with the rotor exactly 90 degrees from the line of the engine. It will be necessary to use a screwdriver or similar tool to move the oil pump drive shaft to align with the pin in the drive gear of the distributor. You will also discover that as you start to drop the distributor down it will rotate. You must move the rotor in the correct direction that insures the rotor be at the correct place when seated. Insure the clamp ring is loose on the distributor. With the retaining washer, spring and bolt in position tighten the bolt. Inside the car move the timing lever to the maximum ADVANCED position. Rotate the distributor counter clockwise until the points are just ready to open. Tighten the clamp bolt. Install the distributor cap and insert the plug wires in the correct holes. The number one plug wire will go in the nearest hole to you and on the right side. Number 2 is in the left hole, number 4 is in the upper left hole and number 3 is in the upper right hole. The rotation of the rotor is clockwise and the firing order is: 1-2-4-3.

You are now ready to start the car. First move the spark control to the RETARD position on the steering wheel. Turn on the ignition and start the engine. CAUTIION , do not race the engine nor allow it to idle for the first few minutes of operation. Remember when we primed the oil system we were only able to fill the 4 troughs. There is NO oil in any of the reservoirs. Therefore, we must run the engine at a fairly fast pace to SPLASH oil up into the cam and main bearing reservoirs. Observe the oil gage to insure we have oil pressure. If there is no indicated pressure, shut off the engine and find the cause.

After the engine has achieved operating temperature it is time to complete the timing procedure. Use a strobe type timing light and if it is 12-volt operation only it will be necessary to use an auxiliary 12-volt battery to power the light. Attach the pickup unit to number 1 plug, and move the spark control to ADVANCED position on the steering wheel. With the engine operating at idle, direct the light through the observation hole in the flywheel housing and by moving the distributor align the pointer on the 25-degree mark on the flywheel. When this is achieved tighten the clamp bolt on the distributor.

You are now ready for a test drive.

If you remember, when we adjusted the valves we set all of them at .007. Leave that adjustment until we have a few hours on the engine and then we will complete the required procedures prior to buttoning up the engine.

Class dismissed to go for a test drive

.

Ray, how do you determine which side of the rim goes to the outside of the car? By the valve stem hole or the small welded knob on the rim edge? Or.........?

Hi MrMack,

The rim can be mounted in one position only.
The split in the rim is at 3:00 o'clock and must be located at a rim bolt. With the tube stem through the hole there is no other way.

That is the way it looks to me, but I have seen a fellow (on a tour) that tried to mount the rim on the disk wheel back side out and it was a bugger to get back off and get turned around.

I was mainly asking about mounting the tire on the rim correctly (for those with white walls with a preferred side out) My tires are solid black so it don't make that much difference, I try to put the red dot opposite the valve stem on the outside of the wheel.

Mention wasn't made about breaking in the cam unless I missed it. On much newer cars, I've always followed the practice to run an engine at 2000 RPM's for 20 minutes to break in the cam properly. Doesn't the same practice apply to older motors??

-Bob