Tamd41a oil cooler

[stelican]

I had one with heavy corrosion into the O ring recess. Had it tig ? welded and machined no further problem. 10+ yeasrs ago.

 

[colhel]

One of my more elaborate ideas is to machine out the old casting and turn an insert c/w O ring groove and press it in. Probably a bit OTT but worth a look?

 

[colhel]

To add to the above, if the insert was made from a similar metal to the tube assembly, would there be anywhere else it could corrode? In theory there should be no water where the dissimilar metals contact, should there?

 

[colhel]

A couple of issues with an insert now I've had a proper look. (a) The wall thickness of the cast casing will be reduced, perhaps too much so, bearing in mind it would need to be bored out to a diameter bigger than the O ring groove. (b) The insert would need a method of keeping it captive as the coil assy is pushed in from the inside.

 

[Mr Googler]

To add to the above, if the insert was made from a similar metal to the tube assembly, would there be anywhere else it could corrode? In theory there should be no water where the dissimilar metals contact, should there?

the area that’s eaten itself (if roughly the same location as mine) is in contact with water all the time as sea water sits in the cooler maybe 1/2 full as it never drains down fully when stopped. the galvanic corrosion sets up. I’m guessing the outer o ring hardens over time and let’s sea water pass to the outside edge.

I had none in the other engine cooler. took 20 odd years for that much corrosion so I don’t think it’s a mega issue. Weld and machine seems the best solution

 

[colhel]

the area that’s eaten itself (if roughly the same location as mine) is in contact with water all the time as sea water sits in the cooler maybe 1/2 full as it never drains down fully when stopped. the galvanic corrosion sets up. I’m guessing the outer o ring hardens over time and let’s sea water pass to the outside edge.

I had none in the other engine cooler. took 20 odd years for that much corrosion so I don’t think it’s a mega issue. Weld and machine seems the best solution

I meant the outside diameter of the insert where it's in contact with the cast casing shouldn't have water contact. I think ?.
You're undoubtedly right though, the weld/putty method is the more sensible route, but as a machinist I tend to look at solutions from where I can use those skills, even if they do seem a bit different/daft.

 

[colhel]

A little sketch of what I think I'm talking about

 

[colhel]

Sorry to bring this back into the fore again but to me an insert is a simpler and more accurate option but once started there's no turning back.
If I were to weld it or epoxy it, the O ring groove still needs either to remain intact with a good surface finish and within a fairly tight tolerance size and shape. Re Machining that O ring groove in the casting is not a straight forward task. I've also thought of a way of mechanically supporting the insert aswell as using an epoxy which was one of my concerns

 

[colhel]

I accept full liability if it goes wrong btw. ?
Any input gratefully received

 

[QBhoy]

Hi. I’ll admit I haven’t read all of the posted comments. If it’s the gear oil cooler you mean..is it perhaps the pencil anode you have the issue with ? Very similar looking cooler to the larger tamd61’s I maintain. They have a threaded pencil anode fitted and threaded into the aft side of the cooler.
Edit…just saw it’s the side mounted oil cooler. Ignore me.

 

[colhel]

Here's the issue. Not a very good pic but you may get able to see the corrosion around the O ring groove. It's this piece I'm considering boring out and replace with an insert.