Testing: The Most Critical Step In Marine Transmission Rebuilds

Today, I want to discuss the final step of our rebuild process. Let’s dig right in, and take a look at this critical step and, specifically, what a proper test looks like at Palmer Johnson.

Our rebuild process for all Marine Gears ends with a test that ensures the transmission aligns with factory specifications. Twin Disc has a specific S-570 test sheet for each marine transmission that ensures all critical pressures are in order, so we start there. After that, our service technicians test flow across the pump and heat-up the transmission for about 30 minutes before beginning our tests. Each Palmer Johnson location has a custom-designed hydraulic supply with a dual canister filtration system that cleans the oil before it goes into the transmission. In the warm-up time we ensure the transmission is brought up to a higher operating temperature -- we use 10 wt. oil to simulate operating conditions. As we run this piece of the test, we’re looking for leaks and proper connections. The technicians are also looking over the marine gear for unusual heat rise and overall noise-free operations.

Once the warm-up is complete we begin a series of Low RPM testing, reviewing and recording all pressures at idle. From here, we begin to throttle up the engine and test at 1800 RPM. With each test, we walk through a series of checkpoints -- each is reviewed and recorded, to ensure proper performance.

Each test we conduct takes around two hours and, in the end, let’s us know that this transmission is ready to be put back into the boat. Our customers count on this high level of testing and diagnostics, and we want to make sure we always have total confidence in the transmissions we install.

To that extent, our team recently designed our own electric test stand to replace older stands. These will be used in the near future -- for now, all locations have a PJ designed stand that exceeds OEM standards.

Want to see more? Checking out this video -- here, we’re testing the Twin Disc Catalina Express on one of our older stands in Santa Fe Springs. It’s one of four transmissions we recently rebuilt for Catalina Express in Longbeach. They were completely rebuilt to OEM standards and had a first-time pass on our test stand. Next, this transmission will be moved to our paint booth where it can be prepped for paint.

Our rebuild process takes into account a high level of detail and our techs are experts in their trade. Because of our test procedures we have less than a 1% field failure rate and we can offer an industry leading one-year warranty. Click here to learn more.