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

Ray
Going back to the photo of your rim, the one with the bow tie that gets your heart going.
Below and slightly to the right is a prominent indentation (from the inside to the outside), there are four of these and are basically there to hold the steel fellow of the wheel in place.
They tend to wobble a bit without this.

Most of the rims in Australia don't have this indentation (probably aftermarket, as our rims suffered in their heyday on our rough roads)

My heart stops when I see one with the indents in it and as our rims appear to be locally made, my heart would miss more than one beat if I came accross one with a bow tie in it

I was presently surprised to see the Jaxon mark on my US import 28, as we didn't even get that.

Also I often wonder when following a Chev 4 (or 29) when I see a rim that appears buckled (and we have heaps of them on cars here) is one without the indent, and just wobbles a bit.
Chris

Ray,
I bought new tires for a recently purchased '28 with a 30 year old amateur restoration. Did not understand the meaning of amateur until I got this car. It has three '28 wheels and one '27 or earlier steel disc wheel. Will not go into the long sad story but, had to re-mount the tires onto the rims on the car during the recent SST. Made a good tire changing seminar for several 4 banger owners.

Also discovered a while back that the rims for '28 were not cadmium plated but painted black. Same for '29-31 disc wheels. Was suprised to find this as I have always thought they were plated. Even the '31 Fire Truck rims are wrong. Looks like '27 was the end of the cad. plated rims, clamps, nuts.

ChevyChip-

Please elaborate on the "black painted vs cadmium plated split rims" statement for 1928. Are you talking passenger car, truck, or both?

In an earlier class I promised we would cover the two decals used on the 1928 engine. There is a decal on the oil filter and also on the air cleaner.



This is the Oil Filter decal. The Air Cleaner is exactly the same except it says: Air Cleaner. As noted both decals are round and several pictures appear in the CSNs for 1927-28.

Bowtie Bob ,

Your comment about breaking in cams is new to me. Can’t see that the cam needs any special ”˜wear-in’ that would not apply to all the other components in the engine.

Chevguroo ,

You are absolutely correct about the 4 indentions on the 1928 rims. They are absolutely critical for a proper fit on the correct 1928 wheels.

ChevyChip ,

You would do all of us a service if you would post your reference for the painted rims. Everything I come up with indicates the cad finish.

Oldie ,

I’m also waiting for the reference.

Along the lines of Bowtie Bob’s comments, I now have a few hours and miles on the engine. Time to initiate the next step.

The first order of business is to re-torque the head. We will use the same values as when initially assembled, i.e., 55-60 pounds. (We have new head bolts). The pattern has already been explained and is available in the Repair Manual.

Check the point setting and then start the engine. The engine must be operated for several minutes in order to bring it up to operating temperature. If you remember on the initial assembly the valves were all set at .007. Now we must set them to the proper specifications, which is: Intake .006 and Exhaust .008. I recommend that a vacuum gage be attached to the engine as a visual reference when setting the valve clearance.



This is a very valuable tool to use when adjusting valves. The wrench part is placed over the stop nut on the rocker arm, loosen the lock nut and then use the built-in screwdriver to make the adjustment. Check progress with a feeler gage. If you make a mistake it should be in the excess. That is, make the adjustment too loose rather than too tight. If the valves are adjusted too tight there is the possibility of burned valves.

Replace the felt oiling blanket back over the top of the valves and lubricate with engine oil. Also re-oil the “O” rings around the top of each pushrod. Replace the valve cover.

It is considered good practice to change the oil in the engine even though it only has a few minutes and miles. This will flush out any debris that may have been in the pan or lodged somewhere else in the engine. As always, I recommend multigrade oil.



The final product.




In the next few days I intend to remove the bulk of the graffiti that has been placed on the blackboard by some of the students. Several members have indicated a desire to either make a CD of this complete thread or in some cases print it. If you want the graffiti included, and wish to copy all of it, I suggest you accomplish this soon. As a reminder, there are two threads under this heading and one thread under the 12-28 section at the top of the page. I will ask a moderator to clean up that thread also.

I have been following this thread with much interest and on reviewing page three I noticed that the top photo is not of a distributor incorrectly positioned. I am now curious as to make and model of the tip truck just inside the door of the workshop.
Is it your workshop or a friends.
Keep up the good work.

Hi tonyw,

Sorry about the confusion. The grimlyns snuk into my machine while I was away.

I think it is fixed now.

That picture, and one more, actually went with the entry about the ALL-CAL meet. The shop is part of the Don Dougherty ( STL TIKN Machinery ) collection in Colfax, CA. I am not positive as to the make of the dump truck, but I think it is a 1924 Autocar Rotary Dump.

Antique Mechanic: Not to beat a dead horse, but cam break-in is critical. Any high performance cam comes with instructions to immediately, upon start-up of a newly rebuilt engine, run the engine at 2000-RPM for 20-30 minutes. I just spoke to my son-in-law, who is a drag racer by hobby and an Engineer for Delphi, specializing in cam design, who confirmed the necessity for proper cam break-in. According to him, 2000-RPM is the lightest load on the cam lobes....under 2000 RPM there's a lot of spring pressure and over 2000-RPM's there's a lot of load due to inertia. The 2000-RPM figure is, for most motors, the best (i.e. lightest - inertia tends to balance out spring pressure at 2000-RPM) load on the cam lobes and thus, the best speed to wear in the cam lobes. If the procedure isn't followed, there's a greater chance of 'scuffing' or 'galling' of the cam lobes. Perhaps on the relatively small power outputs of these early engines, there isn't the load exerted upon the cams, as there is in the higher horsepower engines which have higher spring pressures and RPM's. The oldest engines I've ever rebuilt were 216" Chevy's and I followed the above practice with them.
In any event, it's food for thought and I just thought I'd raise the question.


OK, I'm sitting back down and zippin' the lip (for now).

-Bob

From what little I know of antique 4cylinder engines (lower rpms, low compression,low hp) the most critical "break-in" was for the piston rings; as they related to both the cylinder side walls & the ring land grooves...
then the re-adjusting of the valve lash?

Cam problems were seen once the motor got to operating temp if the block alignment wasn't perfect , or torque specs were improperly done.

Why take a chance? A break in can't hurt anything. I have always been told that a break in was highly important on a new or newly rebuilt engine.

I have not been able to find any explicit pictures of the internal workings of the 1928 parking brake. Based on a request by n j horst, and perhaps needed by others, here is a picture and explanation. (Unfortunately I don’t have any units at this stage of completion, so my apologies for using a picture of a spare rear-end. Just ignore the grease).




This is the brake housing with the axle and brake-drum removed. Identification of the parts:

6. This is the area where the brake drum would be if installed.

5. This is the service brake band and is completely independent of the parking brake system.

4. This is the parking brake band. Where the service brake would be engaged by compression of the band, the parking brake is engaged by expansion.

3. These are the links from the parking brake band to a central control link.

2. This link picks up the two links from the parking brake band and connects them to the actuator arm.

1. This is the actuator arm. The arm pivots on the left end where it is attached to a rod that goes to the parking brake handle. When this arm is pivoted in the direction of the arrow it pulls down the link above which in turn pulls down the two links simultaneously. This action spreads the parking brake band and presses them against the inside of the brake drum.

NOTE: There are actually 4 links at location 3. Two are visible and two are concealed on the backside.

Yet another picture

Mr.Antiquemachanic and Mr.Rustyfender, thank you very much for the time and effert you both took to help out! I could not find the information anywere ? It is Gentalman like you guy's that truly make this site and hobby a delight to enjoy. NJ Horst.

Whilst on the subject of parking brakes, the actual unit that that the lining attaches (shoe/band) to can cause a lot off problems if you do not use the one that came off the diff housing you're putting back in.

I had a problem with one of my Chev 4's (restored by someone else) brakes locking on whilst reversing. It took me a long while to find out why.

The reason was that there are 3 different types of brake bands and diffs. The difference being in the 3 'tags/locaters that stop the shoe/band slipping sideways within the drum.

You can see clearly, in Rustyfenders photo, the bracket on the backing plate where this tag sits in. There are 2 tags, one at either side of the opening (or each end) of the band and 1 tag opposite or at the centre of the band/shoe. This is where the difference lies. This back tag has 3 different locations and fit 3 differently placed brackets on the backing plates.

The 1st type is directly opposite the opening in the band. The second type is offset about 1.5" to the left of centre. The 3rd type is offset 1.5" to the right of centre. The diff housings came out with 3 dirrent positions on the backing plate to accomodate the 3 different tags.

What my Chev has was and offset tag on the band placed on a diff with the centre bracket, so that when you reversed the car,the tag tried to ride off the end of the bracket, rather than slide back and forth as it would in it's correct bracket.

I have kept an example of each of the 3 shoes for demonstration purposes

It all sounds a bit long winded and is not easy to explain, however if you reline an offset shoe and wonder why it doesn't fit properly you'll now know why.

I could probably get some photos and send them over if would explain the differences better

Chris

Your "finished project" is one very beautiful car, you can and should feel a lot of pride in your achievement.

Hope to see the car one day in person. As Roy would say "Happy trails to you...".

A few days ago I was doing the research on the proper label on the 4-cylinder (1927-28) oil filter. I remembered I had a NOS one on display. Today I took it down to verify the label and discovered to my surprise that the box has never been opened. As a result we can’t use it as proof. We’ll just assume there is one in there and it has the round label.

I think I have the picture situation under control, and although this string is not about pictures, here is a tip. The location where you store pictures on YOUR computer must not assign the same identification to more that one picture. If you anticipate uploading a picture and placing it on the Internet it is best to rename the picture a unique and non-duplicate name.

About the comments on engine “break-in”. This is not to devalue the need to conduct some sort of break-in, but to treat a 4-cylinder engine of the vintage we are working with, as a ”˜race’ engine is perhaps overkill. Not at all sure I wish to subject a fresh 4-cylinder engine to 2000 RPM for 20 or so minutes. Of more value in breaking in the engine is to run it at various speeds, listening for any unusual noises and carefully monitoring the engine temperature.

Actually, the proper way to ”˜break-in’ the 4-cylinder engine is as prescribed in the Repair Manual. This method requires the facilities to turn the engine and ”˜burnish’ it. The procedure used a running motor connected to the ”˜unbuttoned’ subject engine. After it had been ”˜run’ for a while or ”˜burnished’ the engine was checked for compliance with specifications and then buttoned up and the engine placed in the final chassis. Very few shops, if any, have the capability to perform this procedure today.

As our ”˜school’ engine has accumulated more miles and hours it has developed an unwanted sound. To the seasoned mechanic this noise would be quickly identified. To the uninitiated, here is a procedure to help locate the noise.

Listen carefully to see if the source can be identified. Noises made by the valve train are included in this category. To narrow the search, use a feeler gage on each rocker arm to see if the noise changes. If it does, readjust the offending valve to the correct specifications.

Internal noises are a bit more difficult to locate. Use a screwdriver to short out each sparkplug in order. Listen for an INCREASE in the noise. If found, this would most likely be rod noises, either at the wrist pin or at the ”˜big’ end.

To identify main bearing noises is the most difficult. If you have eliminated the valve adjustment, passed the rod noise test, then it may be the main bearings. By ”˜racing’ the engine a seasoned mechanic can identify main bearing noises and by use of a broomstick with one end placed behind your ear and the other near the base of the engine against the area of each bearing, listen for a pronounced ”˜thump’. Main bearings do not typically produce a ”˜knock’ but rather the ”˜thump’.

In our case it was quickly determined that number 2 rod was the guilty party. The oil was drained from the pan and then the pan removed. The bearing cap was removed from #2 rod, the crank and rod surface cleaned and dried, and a fresh piece of green PLASTIGAGE placed on the cap. Rod was retorqued,cap removed, and the PLASTIGAGE ”˜read’. The reading was slightly in excess of .003. Shims of the same value were removed from each side of the cap to reduce this reading down to .001-.0015.

In earlier classes the procedure for installing gaskets on the oil pan were discussed with pictures to support the text. This job verified the value of the procedure.




This is the front main bearing cap.



This is the rear main bearing cap. Notice in both cases how the pan gasket is still undisturbed and intact. Close inspection also failed to find any evidence of oil leaks. These results were achieved by gluing only one side of the gasket and by forming special shaped gaskets for each main bearing cap.

A question was asked on the forum recently about the proper installation of cotter pins. I am not saying that the ones in the picture are ”˜the’ solution, but rather the way I have done them for years.

The pan was reinstalled, no washers under the ¼ 20X1/2 round head machine screws, and without any additional sealant. Oil was replenished in the pan, engine started, test run, and then test-driven. Results: PROBLEM SOLVED .

The 1928 Touring will be field tested early next month on the 4-cylinder tour at Lakeport, CA, hosted by Bob Cramer, and then reloaded for the trip to the National tour in New Mexico in late June. Hope to see some of the students on either or both tours.

Hi Ray,
It's interesting how these old engines speak volumes about their condition to the trained ear. No fancy computers, 'check engine' lights, or any of that stuff is necessary if you just pay attention to what the engine is telling you. I wanted to add that if the noise you hear occurs once for every 2 revolutions of the crankshaft, you're probably dealing with a camshaft or timing gear problem.

Regards,
-R