Water in the Lower Unit CD-13A 5.5hp

[MarvK]

I went to replace the oil in the lower unit last night in my CD-13 5.5 last night, and drained out "chocolate milk". :facepalm:

Probably impossible to determine where it's leaking from, I'm assuming I should just install a lower unit seal kit? There doesn't seem to be any external evidence of leakage that I can see.

Can I do all the work by just dropping the lower half of the gearcase/skeg?

Thanks,
Marv

 

[Daviet]

Re: Water in the Lower Unit CD-13A 5.5hp

Before you jump into a reseal job, did you change the seal washers on the drain/vent screws last time you changed the lower unit oil? A lot of problems with a small amount of water intrusion can be traced back to defective seals on the screws. Might be worth the time to install new seals and change the oil and run it and recheck the oil for water.

 

[HighTrim]

Re: Water in the Lower Unit CD-13A 5.5hp

If you determine that there is water intrusion issues, and the problem is not by reusing the crush washers, first pressure test the gearcase. Fill it with 6 to 8 psi and submerge it in water. While spinning the shafts, watch for air bubbles.That will identify where the leak is. May be a seal issue, however may be a worn casting, worn shaft, etc... Resealing will not help with that.

If/when you get determine that it needs a reseal, let us know and we can help with that.

 

[boobie]

Re: Water in the Lower Unit CD-13A 5.5hp

As the service manual says pressure check the g/c at 15psi and vacuum check at 15 Hg.

 

[MarvK]

Re: Water in the Lower Unit CD-13A 5.5hp

Excellent advice gentlemen. That's why I love coming here.:joyous: I'll start with the drain and vent plug washers first.

Now for the silly question; how do I pressurize the gear case?

Thanks,
Marv

 

[HighTrim]

Re: Water in the Lower Unit CD-13A 5.5hp

With the older gearcases sometimes more pressure helps the seals to cheat. I test at a lower psi first, then definitely no more than 15 psi.

There are testers you can buy, but for a guy with only 1 motor not worth it to purchase. If you have a bike pump with a gauge on it, or any type of gauged pump for that matter, attach the fitting from your gearcase oil pump to it to pressurize. Pressurize to 6 to 8 psi first, submerge in water, with the prop and water pump removed. Spin the drive shaft in gear and watch for air bubbles. Then increase pressure and try again. If you do find a leak, inspect the housing, shaft etc... in that particular area. If all is well there, do a complete reseal.