Gear Oil Cooler

[Paul&Ness]

HI, Went to the boat today to do some post trip checks and found that the bilges were full of water. Much higher level than the normal amount I see in the bilges! It turned out that the engine bay bilge pump had burnt out... to cut a long story short, I replaced the bilge pump and float switch with an automatic bilge pump. As it sometimes is with boats the bits that you need to replace are the least accessible and trying to squeeze my big a*se in the engine bay was quite a feat.

Having solved one problem I, rather stupidly, decided to check the gearbox oil levels. Levels in both gearboxes were good but the port gearbox oil has signs of water contamination! So I'll be flushing the gearbox out a couple of times tomorrow but will have to replace the oil cooler.

So I have a questions or two... are Gear Oil Coolers reparable and if so can someone point me in the direction of where I can get them repaired.?If I have to replace the gear oil cooler, where can I get a replacement? ASAP Supplies don't have a like for like replacement, I have just checked. SBMarine in the US do have direct replacements but the cost + import duty make them very expensive.

Any suggestions will be gratefully received :encouragement:

 

[IDAMAY]

I can't really help with the possible repair but I have bought quite a few major items from the US including raw water pumps and have found them less expensive than equivalent items purchased in UK even after adding freight, insurance, import duty and VAT. You may have a bit of a shock when you do find a UK supplier. Which engine/gearbox supplier BTW?

 

[Paul&Ness]

I have ZF220A marine transmissions on Cummins 6BTA 5.9M2's (300hp).

 

[Mr Googler]

I think bowman do i replacement oil cooler. Superheat6k is up on that

 

[Paul&Ness]

Thanks. As long as it's up to spec I don't need a like for like

 

[QBhoy]

Hi
Do you think the water ingress to the gear oil cooler is due to the bilge being full of water or the gear oil cooler passing water through the seals ?
Both, I suppose are worrying.
Why was the bilge getting so full, if the former ? If the latter, perhaps the cooler is passing at the interface seals ?
All the best

 

[Mr Googler]

I had a quick look on the bowman catalogues and for a 220a it was a 3" cooler.

No doubt they will be able to spec the right one. Probably better than OE!!

 

[volvopaul]

I have ZF220A marine transmissions on Cummins 6BTA 5.9M2's (300hp).

You need to find out intajecwater hose size , size of tube stack .
Talk to Mark at Lancing marine .

 

[superheat6k]

I am surprised water is getting into the oil because the oil pressure on a hydraulic box is ~2-300psi, whereas the cooling water is barely a few psi at the gearbox. If the tube stack fails the oil will exit first and the box would stop functioning. However, if water has gotten in there is only one likely source, unless the boat has been flooded at some point.

A cooler is a cooler, so if you can select a Bowman of similar size that will work just fine. Anyway those on the Hurth's on my 6BT's are very similar to Bowman.

I previously replaced the gear oil coolers on my last boat's VP TAMD60C with Bowman at a fraction the cost VP were asking, and for a superior cooler ~£200 for two including all the accessory parts, VP wanted £1,600 for just one. Bowman use Cupro-nickel, not brass - why marine engine makers think it is OK to use brass for seawater cooled coolers astounds me.

I also found some some neat plastic mounts for the Bowman, so when the job was finished they looked like they were original fit. You might need to find some hydraulic adaptors although the VP ones fitted the oil ports on the Bowman.

For the TAMD60C (255HP) with Twin Disc MG 502 I used the Bowman DC 90 unit. I worked out it had a slightly higher internal tube surface area than the VP unit it replaced.

http://www.ejbowman.co.uk/pdf/DC_Oil_Coolers_-_Iss_J.pdf

 

[Paul&Ness]

I am assuming that the bilge filled with water form the dripping shaft seals. I know that they drip faster than the prescribed amount but not by much and the bilge pump, when working, managed the situation adequately. Another assumption at this point is that the oil cooler has failed and small quantities of water are contaminating the oil.

 

[Paul&Ness]

The water in the bilge was not high enough to affect the gearbox.

 

[Portofino]

I am surprised water is getting into the oil because the oil pressure on a hydraulic box is ~2-300psi, whereas the cooling water is barely a few psi at the gearbox. If the tube stack fails the oil will exit first and the box would stop functioning. However, if water has gotten in there is only one likely source, unless the boat has been flooded at some point.

]

When it's not running the G box oil pressure is zero !

If the leaky stack is higher ' then over a few weeks /days ? ---gravity will take its toll and water may seep down into the box
To give the higher "fliud " level readings the OP alledgedly reports .

Bilge a red herring something else unless water has risen upin theGbox and overspilled out from a vent.
Not familiar with that type of box ,if it's possible to do that ??

 

[Paul&Ness]

That was my thought! The amount of discolouration and creamy sludge is minimal so I am thinking the amount of water getting into the oil is small. I will be investigating a replacement for the oil cooler as that would be the most likely cause of the problem. The bilge water was several inches below the level of the gearbox...

 

[QBhoy]

I am surprised water is getting into the oil because the oil pressure on a hydraulic box is ~2-300psi, whereas the cooling water is barely a few psi at the gearbox. If the tube stack fails the oil will exit first and the box would stop functioning. However, if water has gotten in there is only one likely source, unless the boat has been flooded at some point.

A cooler is a cooler, so if you can select a Bowman of similar size that will work just fine. Anyway those on the Hurth's on my 6BT's are very similar to Bowman.

I previously replaced the gear oil coolers on my last boat's VP TAMD60C with Bowman at a fraction the cost VP were asking, and for a superior cooler ~£200 for two including all the accessory parts, VP wanted £1,600 for just one. Bowman use Cupro-nickel, not brass - why marine engine makers think it is OK to use brass for seawater cooled coolers astounds me.

I also found some some neat plastic mounts for the Bowman, so when the job was finished they looked like they were original fit. You might need to find some hydraulic adaptors although the VP ones fitted the oil ports on the Bowman.

For the TAMD60C (255HP) with Twin Disc MG 502 I used the Bowman DC 90 unit. I worked out it had a slightly higher internal tube surface area than the VP unit it replaced.

http://www.ejbowman.co.uk/pdf/DC_Oil_Coolers_-_Iss_J.pdf

The oil pressure is not at these pressure on the return, where it is cooled normally.

 

[volvopaul]

Oil pressure in the cooler on the ZF220 is clutch pack pressure around 450/500 psi, I've stripped a few of these boxes on the 61/62/63 engines where water has penetrated the casing , oil is returned to the box when the selector is in the neutral position then fed direct to the clutches, its volume and pressure is regulated with a relief valve .

 

[superheat6k]

The oil pressure is not at these pressure on the return, where it is cooled normally.

I am not sure about the gearbox mentioned, but the MG502 I am more familiar with the oil cooler is the first part the oil passes through after leaving the pump en route to the clutches.