Our goal with this project is to restore a basket case old race car to the original condition, which means using all the period-correct parts. Unfortunately, with every project, some items are difficult to find, or too pricey to acquire in short order. We found ourselves in this predicament but were unwilling to let that stall our project build.
As we documented in the project’s intro article, the original rearend was a Halibrand Midget quick-change (QC) rear, which was very popular at the time. Sadly, Halibrand was sold by the founder/owner, and the brand was unable to operate successfully without Ted Halibrand at the helm. The company was moved to Santee, California, then sold and moved to Wichita, Kansas, where it eventually dissolved in bankruptcy court.
At one time, practically every Midget race car west of the Mississippi river was equipped with the Halibrand QC rearend. Halibrand’s design and function were so popular that it was copied by Frankland. It is even the design foundation for modern Winter’s Midget and Sprint Car rearends.
The demand for Halibrand products, especially quick-change rearends, is still amazingly high. Speedway Motors offers some rebuild products and manuals for enthusiasts who wish to restore their aging Halibrand quick-change rears.
What We Are Doing
Until we can find a decent Halibrand Midget rearend that is affordable on our modest budget, we plan on using an older Casale Midget rearend that we have on hand. The Casale 101 quick-change was equally as popular as the Halibrand in the ’50s and ’60s. The company shifted manufacturing to meet the boat racing market by manufacturing boat V-drives, and the open-wheel quick-change rearends were almost a thing of the past for the Casale Engineering.
While the Halibrand and Casale housings appear different, the two gear drives are similar. Both were manufactured in Southern California, near the Torrance area. In this case, a Midget car rearend is all we needed to turn our project into a roller. We could worry about getting the period-correct part later.
We needed to get a good idea of what we were dealing with, so disassembly of the Casale unit was a priority. From there we could tell if a rebuild was needed or if we could reassemble and move forward. Google is a great search engine, you can find just about anything you need to know … except how to take apart and put a Casale quick-change rearend back together.
What We Did
Fortunately, the Casale QC and Halibrand QC for Midget cars are very similar, as far as setup and measurements are concerned. A sliding 10-10 coupler connects the closed-tube driveshaft to the rearend input shaft. The distance from the housing face to the axle centerline was almost exact, as well. This makes the two different rearends very interchangeable.
First, a word of caution. Mechanics have gotten used to using heat when removing components that fit snugly together. Remember that many of these older race components were made of magnesium, which catches on fire fairly easily. Once magnesium is on fire, it is very difficult to extinguish. It would be smart to keep any heat sources under 350-degrees Fahrenheit to prevent a problem.
Using great care, we disassembled the entire rearend, laying the parts out in sequence, so we could be sure to reassemble them in the same order. Each part was inspected and replaced if necessary. Starting at the center section, we cleaned up the inside and outside of the case, then removed all of the threaded studs. This is where you must be careful not to damage any of the threads.
Usually, the threads in the case are the first to get damaged, so use heat if you need to, and smooth, constant pressure to remove the studs. We found that using two nuts on the stud as jam nuts, will allow the stud to be removed with a wrench.
Taking Care Of The Threads
Clean the threads using a thread chaser/cleaner or wire brush. ARP makes a quality thread chaser set that includes 1/4-20, 5/16-18, 3/8-16, 7/16-14, 1/2-13 thread-pitch chasers listed for $130 on their webpage. The fine print below the listing explains that the pricing listed is for estimating purposes only.
We did a more in-depth search for ARP thread chasers and discovered the same set for $107 on Amazon. There was also a set with the 3/8-16, 7/16-14, 1/2-13 ARP thread chasers for $21.08, and if you were an Amazon Prime member, it would arrive on your doorstep the next day. Most of these classic QC rearends use 3/8-16 thread-pitch studs on the housing for side covers, input bore cover, and gear-change housing cover – so this set will do fine.
Once the studs and threads have been inspected and cleaned, the stud can be re-installed with red threadlocker. Use care to not over-tighten the studs – they need to be a snug fit only. It is easy to strip the threads in the case if you use too many “ugga-duggas” and over-tighten the studs. The studs have course threads on one end and fine threads on the other. The course threads are inserted in the case housing.
Output And Input Shaft
Two short shafts run parallel in the housing – one on the top, and one on the bottom. The shaft on the bottom of the unit is the input shaft turned by the closed-tube driveshaft. The shaft is fitted on the rear with a quick-change gear that drives the gear attached to the top shaft. The top shaft is the output shaft, as it drives the pinion gear assembly that turns the axle.
Bearings are pressed on the shafts and retained with circlip retaining rings and plate retainers with cap screws. If you disassemble the shaft assembly, use pullers or gentle pressure – don’t hammer or force the bearing out of (or into) the housing.
The same is true of the pinion gear assembly. The bearings on the side cases for the pinion assembly should be considered a matched set. Replacing one requires the replacement of the opposite one as well. Always use heat and a bench or floor press to shoulder the bearings correctly.
We’ve seen mechanics use everything from Gasgacinch sealer and threadlocker to Permatex gasket sealer between the bearing’s surface and the housing seat to limit oil leakage. The same is done between the bearing’s inner race and the shaft. While those sealants are fine, our personal choice is a semi-hardening, silicone-type sealant that will have some elasticity during its use. We also use the same silicone sealant to seal the gaskets on the side case and input case to the center housing – ensuring there is never an issue with which sealant is used in the different areas.
For the output shaft bearing retainer, the hex cap screws are installed with blue threadlocker and torqued down to 20 ft-lbs.
The Side Plate
Unlike the Halibrand rearends, the Casale has only one removable side plate. The other bearing and seal are installed in the center housing (the right side plate is an integral part of the housing). The entire housing and side plate should be inspected for damage, worn bearings or seals. If these components must be changed due to wear, the housing and side plate is heated to 350-degrees, the old bearings and seals can be removed and the new bearings can be inserted into the bearing housing. When the housing and side plate are cooled, the seal can be installed.
The axle should be checked for proper preload before the side plate is bolted to the main case. Setting the axle preload is a procedure that would require a full article to explain the process, but we can explain the preload refers to axle drag. With the rearend completely assembled, the axle shaft is rotated.
If the axle rotates freely, with little or no drag, there is insufficient preload. If it does not move or rotates with a lot of drag, there is too much preload, and the shim pack will need to be adjusted. The preload should be between 40- to 45-inch-pounds of effort to rotate the axle.
The left side plate is installed with red threadlocker and tightened in stages, then torqued to 35 in-lbs. No gasket is used between the side plate and main housing. We used silicone gasket sealer to help prevent any leaks. Gasgachinch is also a favorite with technicians on these older QC rearends. The rear cover is installed without thread locker and torqued to 5-8 ft-lbs.
We found a brake system and rear hubs that fit our two-inch tapered axle rearend. These will be installed on the quick-change so we can make the Midget a full roller. While we still have a long way to go, being able to roll around on its own suspension is going to be a major improvement. Stay tuned as we continue to move forward on this build.