High Torque Starter And Adjustable Push Rods
While we were replacing the oil pump, we decided to replace the original starter motor
with the compact high torque starter from Hot Heads.
On the left is the original starter and solenoid. On the right is the new compact starter.
The original starter weighs 23 pounds. The compact weighs 8 pounds.
The original battery cable was 1/2 inch too short to reach the new starter connections but other than that, the installation of the new starter was easy.
As expected, it turns the engine over much faster than before.
While talking with Bob Walker at Hot Heads, he suggested a set of adjustable push rods should take care of the lifter clacking. Since we had eliminated oil pressure as a problem, and since hydraulic lifters seldom all fail at the same time, Bob thought we had could have thicker-than-normal headgaskets, or some other problem that put the lifters outside of their adjustment range. I supplied him with the measurement of the push rods in the engine (9.584") and he built a set of adjustable rods. By the way, on the 354 poly engine, the intake and exhaust push rods are the same length.
On the hemi 331 354 and 392, they are different.
The adjustable push rods. A series of nuts and threads provides the adjustment and locking.
We started replacing push rods on the driver's side. Bob suggested we adjust the rod until it stops spinning freely and then add one quarter turn. It turns out this is easy enough to do on the upper row of push rods (exhaust) but nearly impossible to do on the lower row (intake) due to access.
Well, you have to start somewhere so we adjusted a few exhaust push rods on the driver's side as Bob instructed, removed them, measured them and took an average of 9.662". We repeated the procedure on the passenger head and the 4 exhaust push rods came out 9.506", 9.532", 9.563", 9.512". We were surprised they were so much shorter than the driver's side. A quick look at the push rods in the heads verified that the passenger side rod adjusting nuts stood higher than the driver's. For some reason, the driver's cylinder head sits significantly higher than the passenger.
The proof is in the pudding, or in this case in the compression test, and since this our first experience with adjustable push rods, we could have messed up adjusting the length.
As the table below shows, we did.
|
Results from first test with adjustable push rods set to best guess |
||||
|
|
Compression |
|
|
Compression |
|
Cylinder 1 |
Zero |
|
Cylinder 2 |
Zero |
|
Cylinder 3 |
35 |
|
Cylinder 4 |
125 |
|
Cylinder 5 |
125 |
|
Cylinder 6 |
135 |
|
Cylinder 7 |
35 |
|
Cylinder 8 |
135 |
The intake rods were set too long on both front cylinders, holding the intake valves open and resulting in zero compression. Cylinders 3 and 7 also had adjustments wrong. But for a first try it wasn't terrible and now we know what to do different, which would be to shorten all the rods.
Passenger side results from second test with adjustable push rods set shorter:
|
Passenger Side |
Intake |
Exhaust |
|
|
|
Length |
Length |
Compression |
|
Cylinder 2 |
9.504 as removed 9.498 new adjust |
9.531 9.517 |
135 |
|
Cylinder 4 |
9.526 9.512 |
9.525 9.519 |
135 |
|
Cylinder 6 |
9.527 9.517 |
9.495 9.519 |
135 |
|
Cylinder 8 |
9.526 9.513 |
9.526 9.517 |
135 |
The first number is the length of the push rod as removed from the initial installation. The second number is the rod adjusted for the second try. We wanted to go shorter on all of them to be sure they were seating but not so short we had clacking. With these new lengths on the passenger side all cylinders fire, there is no clacking from any lifter, all exhaust rods can rotate by fingers, and intakes rotate as well but perhaps not as easy due to limited access. This side is done.
Driver side results from second test with shortened push rods:
|
Driver Side |
Intake |
Exhaust |
|
|
|
Length |
Length |
Compression |
|
Cylinder 1 |
9.661 9.615 loose 9.638 still loose 9.647 |
9.666 9.655 good |
125 |
|
Cylinder 3 |
9.666 9.638 |
9.665 9.657 good |
125 |
|
Cylinder 5 |
9.666 9.648 |
9.668 9.659 |
125 |
|
Cylinder 7 |
9.664 9.648 |
9.666 9.659 |
125 |
In this configuration, all cylinders are firing and we have one, maybe two clacking lifters. Winter has arrived and the next test will wait for warmer weather. In the meantime, we are detailing the carb.
To the carb.