Thru hull fitting

[Bouba]

As with all boat diagnostics the results are inconclusive…and I’ve retreated into comfort food


Any comments (about anything other than my lunch)?

 

[Zing]

As with all boat diagnostics the results are inconclusive…and I’ve retreated into comfort food


Any comments (about anything other than my lunch)?

The boat is not your biggest problem.

That said, it is extremely strange the thru hull was blocked and that so much rust is there. I think you need to understand what has failed. As a wild guess the exhaust water injector failed suddenly in a lump and miraculously stayed together until the thru hull. Thats the first potential source, so I’d pull the exhaust hose off to check it out.

 

[Bouba]

The boat is not your biggest problem.

That said, it is extremely strange the thru hull was blocked and that so much rust is there. I think you need to understand what has failed. As a wild guess the exhaust water injector failed suddenly in a lump and miraculously stayed together until the thru hull. Thats the first potential source, so I’d pull the exhaust hose off to check it out.

It’s a long way down to and through the water separator...up to and through the exhaust gas separator...then suddenly stop when falling into the sea is the easy bit

 

[Bouba]

The boat is not your biggest problem.

That said, it is extremely strange the thru hull was blocked and that so much rust is there. I think you need to understand what has failed. As a wild guess the exhaust water injector failed suddenly in a lump and miraculously stayed together until the thru hull. Thats the first potential source, so I’d pull the exhaust hose off to check it out.

But I will probably take off the exhaust hose soon to check

 

[petem]

Are you sure it's rust and not some fouling?

 

[LittleSister]

You've given us pictures of everything except the supposedly rust blocked skin fitting!

 

[Bouba]

You've given us pictures of everything except the supposedly rust blocked skin fitting!

Unfortunately I cleaned it out as soon as I saw it...at the time I didn’t think to record it

 

[Bouba]

Are you sure it's rust and not some fouling?

Yes, I’m sure...obviously I cannot be 100%...but I’ve handled my share of rust over the years...I had a Fiat

 

[Keith-i]

That valve looks like it has a chromed finish. Is that usual on DZR? I wonder if it is perhaps not as ‘marine’ as it could be.

 

[Bouba]

That valve looks like it has a chromed finish. Is that usual on DZR? I wonder if it is perhaps not as ‘marine’ as it could be.

I have struggled to find any marine reference or DZR online...but I’m not sure it’s in bad condition...tomorrow, if they have the parts in stock I will get the Trudesign fittings

 

[Fr J Hackett]

I have missed this but it has all the makings of a saga to rival that of the leaking diesel tank.

 

[penfold]

I do remember that once during a service, the Onan engineer said if there is rust in the water pump the generator is toast

What context did he say this in? Rust in the sea water pump would be weird as there's no ferrous materials, rust in the coolant pump would also be weird as the coolant should have corrosion inhibitors; if untreated fresh water has been used as coolant then yes, you may have significant problems, not least having used an incompetent/lazy/negligent service tech.

 

[Deleted member 478]

As with all boat diagnostics the results are inconclusive…and I’ve retreated into comfort food


Any comments (about anything other than my lunch)?

With a diet like that, there's another blockage coming your way.

 

[Bouba]

What context did he say this in? Rust in the sea water pump would be weird as there's no ferrous materials, rust in the coolant pump would also be weird as the coolant should have corrosion inhibitors; if untreated fresh water has been used as coolant then yes, you may have significant problems, not least having used an incompetent/lazy/negligent service tech.

He just said if you notice rust coming down the front of the engine it’s toast...it was a while ago so I be misremembering

 

[Fr J Hackett]

That valve looks like it's a Malleable Iron fitting

 

[Bouba]

I have missed this but it has all the makings of a saga to rival that of the leaking diesel tank.

The boat is booked to go back in the water on Saturday

 

[penfold]

He just said if you notice rust coming down the front of the engine it’s toast...it was a while ago so I be misremembering

That would suggest he's referring to seal failure on the coolant pump; unless the cooling system is very marginal in capacity it seems a bit hysterical to state that the whole thing is toast if a seal goes. In any case nothing to do with the thread topic.

 

[Fr J Hackett]

The boat is booked to go back in the water on Saturday

Yeh but the valve and skin fitting could fail and the boat sink

 

[Tranona]

I have struggled to find any marine reference or DZR online...but I’m not sure it’s in bad condition...tomorrow, if they have the parts in stock I will get the Trudesign fittings

DZR are normally marked CR (corrosion resistant). Not plated like yours which is almost certainly plain brass. Look for Maestrini brand for DZR. The skin fitting should also be DZR or bronze - although yours look fine. In practice the ball valve is not a big problem - almost all production boats are fitted with plated brass valves and rarely fail, primarily because none of the brass body is actually exposed to seawater - it is usually the ball or spindle that fails. The real weakness is the fittings, particularly the hose tail which you cannot see. This is exposed to seawater coming down the pipe and over time may dezincify.

If it were my boat I think I would just give the whole fitting a good whack with a leather hammer (I have one for removing the spinners on my wire wheels!) to make sure the fittings are sound plus check it will open and close freely. Really don't see a need for replacement at this point.

Can't explain the deposits you found in the outlet, but everything in your photos looks "ordinary".

 

[Bouba]

DZR are normally marked CR (corrosion resistant). Not plated like yours which is almost certainly plain brass. Look for Maestrini brand for DZR. The skin fitting should also be DZR or bronze - although yours look fine. In practice the ball valve is not a big problem - almost all production boats are fitted with plated brass valves and rarely fail, primarily because none of the brass body is actually exposed to seawater - it is usually the ball or spindle that fails. The real weakness is the fittings, particularly the hose tail which you cannot see. This is exposed to seawater coming down the pipe and over time may dezincify.

If it were my boat I think I would just give the whole fitting a good whack with a leather hammer (I have one for removing the spinners on my wire wheels!) to make sure the fittings are sound plus check it will open and close freely. Really don't see a need for replacement at this point.

Can't explain the deposits you found in the outlet, but everything in your photos looks "ordinary".

This is an underwater fitting so it’s constantly exposed to seawater...I gave it quite a bit of wellie today trying to work the ball valve...so it feels strong..but if I can find the composite Trudesign parts tomorrow then I will install them