AD41 engine anodes

[mbird]

Hi All

Oil changing the engines at the weekend if I can spare the time, so I thought while I was at it, I would also change the heat exchanger anodes, not knowing when they were last done.

I have bought new anodes and also the brass anode carriers, which have a tapered thread on them. I presume it is a simple matter of unscrewing the old and replacing with the new? Would you put PTFE tape around the brass tapered thread to help eliminate any potential leaks??

[Antares_9]

Drop of thread sealent is what I normally use Mark, I know it's a bit pedantic but I would be concerned about PTFE tape preventing electrical continuity between the carrier and the main body of the engine or exchanger.

[mbird]

Hadn't thought of that David Electrical continuity is exactly what you DO want with an anode I suppose

[Guest]

A Copper washer might be a better bet if it hasn't already got one. If reusing copper washers heat it red hot on the hob and then quench straight away in water to soften the copper. This goes for fuel line banjos as well.

Jonathan

[Antares_9]

Normally I would agree Jonathan, but tapered threaded bungs and carriers have no "face" for a washer to seal against, even the thread seal can be a bit unnecessary as a properly tightened taper thread will usually seal on its own by the very nature of the design.

[Guest]

Just reread your post and see they have a tapered thread which is quite unusual for brass in brass. So as has been suggested thread seal is better. Hermatite red gasket seal works well for water and oil. You can check your continuity after with a multimeter and add an earth bond if needs be.

Jonathan

[mbird]

Ok, time to look stupid

After doing the oil changes on Sunday, it was time to sort the anodes. Errr, where are they???

Information I have seen showed the anode as being screwed into the ends of the heat exchanger. One end of my heat exchanger is just a blank plate, and the other has a very small bolt head in the middle with two hose connections by the side of it. No anode??

I did find another bolt head protruding from the bottom of the exchanger, but having removed this now need to top up the coolant as it turned out to be a drain plug.....

Any ideas where they are supposed to go, as I couldn't see anything on the engine that looked remotely like the bits I've bought!

[Guest]

Ok, time to look stupid

After doing the oil changes on Sunday, it was time to sort the anodes. Errr, where are they???

Information I have seen showed the anode as being screwed into the ends of the heat exchanger. One end of my heat exchanger is just a blank plate, and the other has a very small bolt head in the middle with two hose connections by the side of it. No anode??

I did find another bolt head protruding from the bottom of the exchanger, but having removed this now need to top up the coolant as it turned out to be a drain plug.....

Any ideas where they are supposed to go, as I couldn't see anything on the engine that looked remotely like the bits I've bought!

If the two hoses are raw water then the bolt head in the middle is probably the anode. the plate on the opposite end is for access for cleaning through the raw water channels in the heat exchanger.

[mbird]

After spending half an hour with Gary at Brundall Marine Services going through all the Volvo part diagrammes, the conclusion is that the AD41P-A engine has NO anodes . The heat exchangers are different on the AD41A and B versions, so Keypart's website has some erroneous info.

Now to set about obtaining a refund for parts supplied in error