Introduction
Although the gearbox pressure test gave good results I'm worried about the state of oil seals in my Selva Madeira 40 outboard. Last time I changed the gear oil it was grayish and the outer oil sea on the propeller axis does not look particularly healthy. I think it's time to replace the oil seals. In order to do that one needs to open the the water pump and remove also the bearing carrier from the gearbox.I decided to order new oil seals, O-rings etc. once again from Engine Marine Part.
Since the water pump needs to be opened I decided to change the impeller, grommets and O-rings just to be on the safe side.
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| The parts that I'm planning to replace. Parts #83, #82, #8 and #7 are the oil seals. |
The oils seals under the water-pump
First I removed the water pump from the lower unit. The oil seals are in the pump support, first you need to remove a metal ring which locks those. I found that the oil seals were quite stuck, I sprayed some penetrating oil and used a socket to extract them. I was extra careful not to make any scratches. |
| Using a socket to extract oil seals from the pump support. |
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| The oils seals removed. They were a little corroded and not in very good shape. |
The new oils seals looks very similar but the upper one has less opening than the lower one.
It's important to put those in the correct order and so that the back sides touch each other.
I applied some O-ring lubrication and was able to push the oil seals in place without any tools.
The metal ring was a little more trickier to get in place, it's easier when you put first the section with the gap.
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| The new oil seals. Selva parts #3550160 and #3555020. |
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| The new oils seals are in-place and locked. |
The oil seals on the propeller shaft
I have noticed that the outer oil seal on the propeller shaft does not look healthy, a lip of the seal is visible so it might have broken internally.
In order to change the oil seal one can do it the proper way or the hack way.
I chose to do it the proper way because I don't want to damage the propeller shaft in any circumstances.
The problem is that the bearing carrier must be removed and in my Selva Madeira it has not been removed since it was assembled in the factory. I had a feeling it's quite stuck and I was correct about that!
Luckily I was able to open the screws holding the carrier. The lower screw was quite tight and I sprayed penetrating oil and turned it back and forth in order not to break it.
I bought a puller that seems to be very compatible with this Selva outboard.
I first tried pulling the carrier using a thin rope but the rope just snapped.
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| The first attemp to remove the bearing carrier - no luck. |
On the second attempt I switched to 4 mm chain, no luck either, metal was just pending.
I realised that I need to use heat and connect the puller using stronger material, I used propane/butane gas torch to heat the gear box, I noticed that the paint took some damage but not that bad.
Still quite a lot of force was needed until the carrier started to move. After that it was quite easy to extract.
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| The carrier started to move. |
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| Almost extracted. |
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| Selva Madeira 40 bearing carrier, Selva part #2045440 |
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| The bearing carrier upside down |
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| The gear case without bearing carrier. |
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| Time to extract the oil seals. |
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| I noticed that the outer oil seal was damaged inside. |
I used a flat head screw driver to extract the oil seals, I was extra careful not to scratch the inner wall of the carrier. I used a socket to push the new oil seals in place. I used once again heat when I put the bearing carrier back but not too much to destroy the new O-rings that I have also changed.
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| The new oils seals are now in place. |
After reassembling the water pump I did a new pressure test and the lower unit was able to maintain steady 10 PSI pressure for three minutes at least (I did not continue the test longer).
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| Pressure test with 10 PSI pressure for 3 minutes, no drop in the pressure was detected. |
