Bucher HPU Heat Exchanger Installation | Step-by-Step Guide from AutomationDirect

We’re going to add a Bucher heat exchanger to a hydraulic power unit. These heat exchangers are designed specifically to fit the Bucher hydraulic power units to reduce heat buildup during higher duty cycles. By maintaining a lower oil temperature, hydraulic fluid lasts longer and components work more effectively, having a higher life expectancy. All brackets and hardware are included for mounting to the HPU motor. A few notes before we get started: This installation is specific for the power unit and the heat exchanger so be sure to check the instructions that came with your heat exchanger because the installation varies a bit between models. The heat exchanger core uses copper tubing, so the inlet and outlet ports must be held with a wrench when the fittings are tightened. The barbed fittings have swivel ends, so ensure that the hoses do not rotate when tightening, as this may kink the hoses, causing excess back pressure. SAE fittings use O-rings to seal, so do not over-tighten. Before the heat exchanger can be installed, the path of fluid through the return filter manifold must first be modified. Unscrew the filler/breather cap from the reservoir and set it aside. Then, loosen the 4 socket-head screws holding the filter manifold to the base manifold and remove the filter assembly. Notice the absorbent pad. Even though we have not run this unit, there is still oil in the filter assembly from the factory test, and yes, I found out the hard way. Plug this outlet on the base manifold with the included ½” NPT plug as shown, ensuring that the O-ring around this passage remains in place. At this point, we went out of order from the instructions - we replaced the filter manifold, then proceeded with the next steps. Ensure that all the O-rings are in place on the base manifold and reinstall the return filter manifold assembly to the base manifold. Snug up the 4 socket head cap screws, then torque to 9 ft.lb . Reinstall the filler/breather cap. Next, remove this #10 SAE plug from the rear port of the base manifold and install this included 90° elbow, position the elbow to point up and tighten the lock nut. Remove the #12 SAE plug from the adapter in the filter manifold return port and install the other included 90° elbow and position the elbow to point up as well and tighten the lock nut (do not over tighten). Now we’ll install the actual heat exchanger. Install the heat exchanger bracket to the motor using the four included 1.5” long bolts washers and nuts but leave these slightly loose to allow alignment of the bracket and heat exchanger. The rubber gasket needs to be attached to the heat exchanger housing opening. You may need to cut off excess. Then position the heat exchanger on top of the electric motor and install the two 1” long bolts, washers, and nuts to secure the heat exchanger to the bracket, and leave slightly loose to allow alignment. Now, align the bracket and heat exchanger on top of the motor so that the heat exchanger sits level on the fan shroud of the motor (there should be no gaps between the rubber gasket and the fan shroud). Snug up then tighten the 6 sets of and bolts securing the heat exchanger and bracket. Install this 90° elbow into the inlet port of the heat exchanger and position so it’s pointing out this end. Again, the heat exchanger core uses copper tubing so the inlet and outlet ports must be held with a wrench when the fittings are tightened. Install the straight fitting into the outlet port of the heat exchanger and again, be sure to hold the heat exchanger fitting with a wrench. This ½” hose needs to be cut into two pieces, 16” long each, and install by placing the hex end of the fitting against a flat surface and pushing the hose over the barb until the end of the hose meets this yellow plastic ring near the hex. GH012119 Install one hose assembly between the base manifold and the heat exchanger inlet and the 2nd hose between the heat exchanger outlet and the return filter manifold inlet as shown on the then tighten all 4 hose ends making sure to hold the fittings at the heat exchanger with a wrench to avoid damage to the copper heat exchanger connections. So that’s all there is to it. Now it just needs to be run to check for leaks. Speaking of leaks, you may have wondered about the barbed fitting use. None of this system will be exposed to high pressure, we’re only dealing with the filter circuit which operates at around 15psi. Find hydraulic components for your system here. See our award winning support options here and subscribe to be notified of new products and solutions.