We get it. There’s a ton on your plate and often some maintenance practices, like changing the oil in your sprayer, can fall by the wayside. Our technicians often get asked how often we recommend changing the oil in a pump crankcase. Of course, we defer to manufacturer recommendations, but thought it might be helpful to run through the process with one of our more popular pumps, the Hypro D30 Diaphragm Pump, especially as the sprayer season winds down.
For those of you unfamiliar with this product, Hypro diaphragm pumps come with oil in the crankcase. Unlike your vehicle, accessing oil in the crankcase take a little more effort.
The manufacturer recommends changing oil after 40 hours of break-in operation and then every three months or 500 hours, whichever comes first. So this means that you should change the oil in this particular model at least four times a year, if not more. Now Hypro recommends using its own brand of oil for this model - Hypro Oil (part number 2160-0038) is specially formulated, high-grade, nondetergent, SAE 30 weight oil designed to prolong pump life.
Now that we have that covered, let’s talk about the three steps to changing the oil in your spray pump.
Step 1. After you’re done with your sprayer for the day, flush the pump with clean water.
Step 2. To drain the oil from the pump, remove the oil drain plug and rotate the shaft until the oil stops flowing out. If you have time to open the pump and inspect the diaphragms, now is a good time, but not mandatory.
Step 3. To fill the pump with oil, slowly pour the oil into the sight tube while turning the pump shaft. Turning the pump shaft purges all the air out of the crankcase. So you won’t have to deal with air bubbles or a less than full amount of oil. If you do decide to replace the diaphragms, always change the oil.
One quick note, for winter storage, which we’ll get into later here on the blog, or if you encounter freezing conditions, flush the pump with a 50/50 mixture of water and antifreeze.
Lastly, keep in mind that most manufacturers recommend changing the oil in your pump every year, if not sooner. We’d actually go as far as to say that it’s highly recommended that the oil be changed at both the start and the end of the sprayer season so that any contaminants entering the crankcase can be removed before sitting in the pump all winter and that you get rid of any buildup from the off season.