View Single Post
  #14   IP: 73.212.127.75
Old 06-28-2017, 09:14 PM
Nanook Nanook is offline
Senior Member
 
Join Date: Nov 2016
Location: Temporarily exiled to Annapolis
Posts: 17
Thanks: 0
Thanked 3 Times in 3 Posts
Barnacle Buster is non-acidic, runs about $30 a gallon, and will destroy zincs if used in a heat exchanger on a FWC engine.

I like to follow Don's advice about blasting the 1/8" drain fittings with dock water to loosen the crud up and out before I do anything else.

Either run the engine up to temp and then a bit more; shut down; shift intake and exhaust cooling hoses to a bucket with the BB in it; remove heat exchanger zinc if FWC; (block the exhaust/water fitting with a damp rag to keep fumes out) run until the gallon has circulated through a few times; shut off and let set. You can run again for a few minutes at a time in the bucket closed loop to keep the temp up and Tstat open or normalize the hoses and let normal water blast everything out when you eventually run it hours/days later.

Or...pull impeller and thermostat (RWC)//pull impeller and heat exchanger zinc (FWC). Shift hoses to bucket as above, then flush or even better back flush the BB through the exhaust manifold and engine using a small electric bilge pump for several hours. Normal up the exhaust side, reinstall the thermostat (new gasket would be great but torque is critical) and run the engine to suck most of the now nasty-smelling fluid out of the bucket while leaving the solids in the bottom.

Normal up everything and run up to temp again to verify everything is good while thoroughly flushing everything out with higher RPM bumps.
Reply With Quote