Replacing the oil pump 3 -- First Steps and Overview -- Universal 5424 M30

Starting the job -- Overview:

(photos to come ...)

First ...

• Make sure all seacocks are closed!
• Put oil and coolant absorbing materials under the engine. Prepare for spills!

Then ...

• Drain both the coolant and oil from the engine. Remove oil filter.
• Disconnect batteries
• Remove alternator and belt
• Remove Air breather/filter
• Remove coolant hose from lower right side of front case
• Remove small coolant hose from internal water pump
• Remove hose from raw water pump to heat exchanger
• Remove hose from seacock to raw water pump
• Remove crankshaft pulley
• Remove throttle linkage from speed control
• Unbolt speed control panel on top of case and access cover on left side of injection pump
• Remove two springs from speed control group
• Remove speed control group

NOTE: The internal water pump and the raw water pump can be left on the front cover. The only part, other than bolts and the hoses mentioned above, that connect the front cover to the engine block are the two springs on the speed control plate.

Details

1. I assume you know how to drain the engine oil and coolant and remove the oil filter.
2. The batteries should be disconnected so you don't short out the alternator or regulator when disconnecting the alternator leads. Otherwise removing the alternator and belt is straightforward. As always tape and label the leads if you think you will not remember where they attach to the alternator.

   

   Alternator, bolts and belt

   
   
   
   

   

   Air breather/filter assembly

3. Removing the air filter/breather is as simple as disconnecting the hose to the air intake on the engine block.
4. Removing the coolant hose from the water pipe on the right side of the engine is largely uneventful. If you have a water heater connected to your coolant system this hose may spill coolant so be prepared to catch any spills.
5. The short hose that connects the engine block to the internal water pump may leak a bit as well.
6. Both hoses connected to the raw water pump will leak sea water. No worries.
7. Ah, the crankshaft pulley ... this can be a bear. The nut holding the crankshaft pulley is huge -- 46mm. Kubota makes a special deep well socket for the nut if you want to spring for it. Otherwise you may have to fabricate your own. In my case the nut came off easily by tapping a corner of the nut with an old screwdriver and hammer. 





Crankshaft pulley, nut and washer

1. Behind the nut is a washer. Remove it as well.
2. You will need a gear puller to remove the pulley as it is on a tapered shaft. Do this gently especially if the pulley has not been removed in the past 30 years or so.
3. Once the pulley is off you should see the black oil seal around the exposed end of the crankshaft. This seal is inserted in the front gear cover and will come out with and when the cover is removed.
8. The speed control panel is attached with four nuts/bolts on the top of the front gear case. It has a spring loaded lever on top. The linkage is connected with a small nut attached this lever.
9. The front left and rear right nuts on the speed control panel are attached to studs that are inserted in the front gear case. The remaining two are bolts that will come out of the case. The access panel is located on the top left side of the engine. It should have a warning label attached to it.
10. Do NOT force the speed control panel when removing it. There are two small springs, one attached to the lever on the speed control panel and a smaller one attached to an internal stud on the front gear case. At this point you only need to remove the larger spring attached to the lever on top of the speed control panel. I found this easiest to do by by gently lifting the panel off the studs and using a pair of angled pliers to get  at the point where the spring attaches to the lever. I left the spring attached to the linkage in the engine block. Do not stretch or otherwise damage this spring or you will have to replace it. 



Speed control panel, bolts, nuts to studs, gasket and small spring.

11. Once the spring has been removed the speed control panel and gasket can be removed. Look in the hole you just created in the top of the front gear cover and you should see the smaller spring on the right side. It is easy to get to now.
12. Now that you have removed all these bits, you are ready to remove the front gear case.

All bits removed and front case is ready to be unbolted.

Parts List -- Universal 5424 M30

First things first -- The parts:

If you haven't heard, the Universal 5424/M30 is a marinized version of the Kubota D-1101 engine block used in Kubota's L245 tractor. It is much cheaper to get engine parts from your local Kubota dealer than from Univeral/Westerbeke. Of course, the parts that are specific to a boat and not a tractor must be acquired from Westerbeke. If you go to a Kubota tractor dealer for parts you will have to reference the L245 tractor as they probably will not know the engine apart from the tractor that uses it.



I found a comprehensive list of Kubota part numbers for this engine. You can find it here.

As you can see there is a significant savings if parts are bought from Kubota directly. With this job I saved $ 250: $145 from Kubota and $395 from Westerbeke. This, for the same parts!

Replacing the oil pump -- Universal 5424 M30

Low Oil Pressure

The story begins when I finally got around to replacing the oil pressure switch. When I purchased Elizabeth the oil pressure idiot light did not work and it took me almost four years to get around to replacing it. Stupid, I know. When I replaced the switch and started the engine the light came on and would not go off. Stupid, I know. Still, the engine has always ran fine, sounds good, does not overheat. Oil obviously circulates as it gets dirty and the oil filter fills. I was not sure if the new oil pressure switch was bad or if indeed the pressure was low. I purchased an oil pressure testing gauge as well as a mechanical gauge to replace the idiot light so I would always know exactly what the oil pressure was. Testing the pressure at the switch port I discovered the pressure at idle was about 5psi and at half throttle around 15psi. The specs on the oil pressure switch suggest that it will circuit will be broken (the light will go off) between 30psi and 60psi. So theoretically, this should be the normal range of the oil pressure. Mine is way too low. I installed the mechanical gauge and the readings were the same. At this point I was feeling really stupid for waiting so long.

So now what? There are many potential causes for low oil pressure. I first went through the obvious and easy possibilities; wrong oil, low oil level, clogged or faulty oil filter. All were good. The next easy cause is one of the two oil pressure relief valves being stuck in the open position, tricking the engine into thinking the pressure was too high and returning the oil to the sump without sending it to the rest of the engine. I removed and cleaned them and still the problem persisted. The problem still could be as simple as the primary oil filter, just a screen really, being clogged with crud. This filter is located on the pickup tube in the crankcase. To get at it, however, is not so easy as the engine would have to be lifted out of the boat to remove the crankcase. Along the same lines the pickup tube that is immersed in the oil and carries the oil to the oil pump may have become disconnected. This, as well is under the engine in the crankcase. Uh oh, major expense.

So that brings me to where we are today. Before pulling the engine I can replace the oil pump itself and check the forward plug on the camshaft. These are two possible culprits as well and can be accessed from the front of the engine. A big(ish) job to be sure and one I have never undertaken before on this engine. Sigh. So here goes.