Ozdobné válce Volvo Penta: série DPH a DPR

The Volvo Penta DPH and DPR series is the replacement of the previous DP-series. Since the Z-drives are significantly heavier, in order to withstand the higher torque of the D4 and the D6 engines, the whole trim system had to be redesigned. Someone with basic knowledge of physics would understand why the new trim cylinders are significantly “bigger” compared to the previous generations. The correlation between pressure and surface is inverse, which means that using the same amount of force and a larger piston, the cylinder manages to lift a heavier transmission without rising more pressure.

The trim cylinders of this family are not identical per side. Therefore, we have the starboard side 3888301, replaced by 21840806, and the port side 3887960, replaced by 22121309. The port side includes more variations, like 21840807, and is serial-number-related. Regardless of the changes, its internal components are interchangeable.

Similar to the previous generations, these trim cylinders are considered non-serviceable components, which should be recycled when their lifecycle ends. This is a considerable cost, especially on a twin-installation, and a serious reason to check Poseidon Marine components to revitalize your trim cylinders.

SYMPTOM	CAUSE	FIX
Leak of hydraulic oil from the top cap	Damaged pressure seal or corrosion on the cap.	Seal kit or a new cap kit.
Z-drive cannot maintain “UP” position	Damaged piston seal	Seal kit or a new cap kit.
Leak of oil after a new cap kit is placed	Deep groove on the rod, made by the movement of the scraper seal.	New rod and seal kit.
Damaged thread on the cylinder.	Improper fitment of a hose led to cross-threading	Usually, machining is difficult there; new cylinder.

Poseidon Marine offers the following components, which are very popular among the DPH & DPR owners, and are specially designed for the aforesaid problems:

PoseidonMarine® Seal kit power trim Volvo Penta DPH DPR hydraulic cylinder 3888301 21840806 22169
PoseidonMarine® Trim Cylinder Rebuild kit Volvo Penta DPH DPR 21840806 21840807
PoseidonMarine® Trim Cylinder Rod Volvo Penta DPH DPR 3888301 21840806
PoseidonMarine® Trim Cylinder tool wrench nut removal Volvo Penta 872612 3860881 19876

Two flexible trim hoses come from the trim pump to the starboard cylinder. The reference 21721548 (ex 3809559) (№3) is connected to the inner port of the cylinder, near the transom plate side. The other hose 21721550 (ex 3809560) (№4) is connected on the opposite port of the same cylinder. In order to perform a trim cylinder repair, the split pin 967707 must be removed so that the clevis pin 21264883 is freed.

Doing so, the cylinders will remain attached to the transom shield, as below:

DPH transom shield, with the trim cylinders still attached on it.

Then, you can use a “PoseidonMarine® Trim Cylinder tool wrench nut removal Volvo Penta 872612 3860881 19876” tool to loosen the cylinder gland and pull out the rod-cap assembly, with its piston at the bottom.

See LessSee More

Frequently Asked Questions About Volvo Penta DPH and DPR series:

The DPH hydraulic cylinder is leaking oil from the cap. How to fix it?

The leak may be related to the pressure seal within the cap, or to a deep groove formed on the rod. You have to either reseal the cylinder or replace the rod.
The trim system fails to maintain the trim-up position on a DPH. What to do?

It seems that the piston seal within the cylinder is worn. You need to tear down, clean, and reseal your cylinder, provided your trim pump works properly.