Volvo 2030 gearbox question

[StevenJMorgan]

I'm going through my cooling system replacing all of the pipes. I have a water cooled gearbox which takes water into a brass fitting at the back of the box and passes it out on the other side.

On removing the hoses to both sides of this fitting i noticed a deposit within the hoses so went a step further and removed the L shaped copper pipes that go into the fitting on the gearbox. Inside the copper fitting was a lot of what seemed like grit so I had a good poke around with a screwdriver to try and clear this out. What should this fitting look like when new and should water pass in to one side circulate into the fitting in the gearbox and exit the other side or should some water pass straight through.

Beginning to wish i had left well alone now as I'm scared I may have buggered it up.

Does anyone have a link to the manual for the gearbox.


Any help greatfully recieved.

 

[scottie]

if you look here www.marinepartseurope.com you will get a drawing
it sounds like the oil cooler you are talking about

 

[pvb]

The fitting on the back of the gearbox has a coil of pipe connected to it inside the gearbox. Water circulates through this pipe to cool the oil in the gearbox. I'd imagine all the water entering the gearbox is meant to go through this pipe. The pipe is shown as part 51 in this diagram - I know this is a different gearbox from yours, but the oil cooler pipe is the same part number, and it'll give you an idea of how it works. It's unlikely you've done any great damage, maybe you should just put it back together!

 

[StevenJMorgan]

Thanks guys - most helpful. I think its a case of put it back together and monitor waterflow, gearbox temp and make sure no water is mixing with the gearbox oil ...

 

[VicS]

[ QUOTE ]
I think its a case of put it back together and monitor waterflow

[/ QUOTE ] But give it a good blast through backwards with a hose first. No sense in putting it back together if its partially blocked. Check the oil afterwards for signs of water but if there's no signs of oil leaking then it's almost certainly OK.

Dont know your plumbing but if you connect a hose to the outlet side and take the element out of the cooling water intake strainer you should be able to back flush it without filling the bilges.

 

[Heckler]

its pretty much as the same on my bene, the cooling water goes thru the gearbox first on its way to the suction side of the raw water pump. if its exiting the boat thru the exhaust in its normal quantity then all should be ok.
stu

 

[Ruffles]

[ QUOTE ]
its pretty much as the same on my bene, the cooling water goes thru the gearbox first on its way to the suction side of the raw water pump. if its exiting the boat thru the exhaust in its normal quantity then all should be ok.
stu

[/ QUOTE ]

StevenJMorgan,
Make sure you're using a hard walled pipe upstream of the pump. A slight blockage in the strainer can cause the pipe to collapse if you use normal radiator hose, resulting in zero flow rather than reduced flow.