Exhaust manifold rusting

[Boobie Trap]

Here is a picture of my engines. Volvo 5.0L Gli.
I know this is part of the exhaust manifold but what is the exact name of the rusting part?

Each engine has two on each side and those four parts are the only thing that is rusting on the entire engine.
It has been in salt water but that was 6 years ago and there is no water leak any where.

It has something to do with the heat exchange but I would appreciate it if someone with some engine knowledge could tell me just what the
heck is going on and why!

Thanks

 

[Bondo]

Re: Exhaust manifold rusting

Ayuh,.... They're 3" riser blocks, that were never painted...

It's got nothin' to do with a heat exchanger, they're to raise the tippin' point of the exhaust flows to well Above the outside water level...

 

[Boobie Trap]

Re: Exhaust manifold rusting

OK, so they are riser blocks. From looking at them, you can't tell in the picture, they were painted at one time. Besides, are any parts of an engine NOT painted today?
So... if they were or were not painted, what is making them rust?
Would it help to spray them with WD-40 or some lube to prevent the rust?
Thanks

 

[Don S]

Re: Exhaust manifold rusting

So... if they were or were not painted, what is making them rust?

Poor paint job. They may not have been painted when new and someone just painted them with a rattle can a couple of quick coats. Impossible to say for sure at this point.

Why don't you clean the rust off and repaint?

 

[Bondo]

Re: Exhaust manifold rusting

OK, so they are riser blocks. From looking at them, you can't tell in the picture, they were painted at one time. Besides, are any parts of an engine NOT painted today?
So... if they were or were not painted, what is making them rust?
Would it help to spray them with WD-40 or some lube to prevent the rust?
Thanks

Ayuh,.... Guess it were'nt very good paint..... or just poorly done,...

I use Rustoleum enamel,... Wirebrush 'em off, 'n paint 'em up...

For overall rust protection of unpainted, or painted surfaces, google up Fluid Film....

It's Great stuff....