Preventing Manifold Corrision

[PTH]

I have a 2001 Volvo 7.4 GI/DP. An overheating problem revealed impeller teeth broken off, rear water **** seal leaking and exhaust manifolds and risers corroded. This engine is 2 years old and has only been run 116 hours. It also has been flushed routinely with fresh water and Salt-A-Way.The boat is stored on a lift. I was very disappointed with the poor results as described.<br />Has anyone else had such poor service on their Volvo?<br />I am considering having an aftermarket fresh water cooling system installed. Could anyone recommend one and who to contact?<br />Also, I am considering adding the Neutra-Salt system recommended by Volvo. <br />Has anyone had any experience with this system?

 

[akriverrat]

Re: Preventing Manifold Corrision

do you flush running engine on hose with muffs?

 

[snapperbait]

Re: Preventing Manifold Corrision

Waterpumps, more specifically impellers have a service life expectancy... If you're on the original impeller with 116 hrs. in two years, you are due to service the waterpump..<br /><br />Cast iron manifolds will only last so long with saltwater use and even with routine flushing, replacement after two to three years is the norm reguardless of engine use... <br /><br />Think of exhaust manifolds, or anything else made of cast iron like the engine block; that comes in contact with saltwater as "disposable"... I tell people that manifolds and risers are like the tires on your car, eventually they must be replaced....<br /><br />Fresh water cooling is the only way to fly in saltwater... Many FWC kits can be found here. http://ebasicpower.american-data.net/Merchant2/merchant.mv?Scr een=CTGY&Store_Code=ebasicpower&Category_Code=COOL

 

[oldboat1]

Re: Preventing Manifold Corrision

Fresh water cooling (closed cooling) still involves pumping raw water through the manifolds and/or the risers. Keeping salt water out of the engine block is a real money saver, though --particularly if the manifolds are also protected.