Yes I did. Twin 454's . . . They had 740 hours in Lake Winnipesaukee and I converted the engines before running them in salt water (Cape Cod). The engines now have 980 hours.
I did not do the oxalic acid flush until a few years after the closed cooling system. Probably a good idea to do it before converting though . . .
if fresh water, you will need to flush out the sand, rocks, dead fish, etc that is trapped in your block
if salt water and you have more than a few hours (under 10) then you may
if salt water and more than 20 hours, damage already done, oxalic acid wont cut it.
How do I do the flush before converting? I was figuring I would install the system, flush with oxalic acid, nutralize with baking soda, rise with water, drain, then add coolant. Thoughts?
I would do all flushing and neutralizing before installing. Flushing after installation has a good chance of leaving crud in the block and also plugging the heat exchanger.
How do I do the flush before converting? I was figuring I would install the system, flush with oxalic acid, nutralize with baking soda, rise with water, drain, then add coolant. Thoughts?
a freshwater motor will hold about 3-4# of rocks and sand.
you need to flush this prior to your conversion.
fastest way is to pull the motor, pull the heads and with the engine on the stand and upside down, blow out the cooling passages.
however you can use a rig like this (made with 1/4" tubing and a hose adapter from lowes), and flush the block from the drain plugs. it takes a few times each motor with about 15 minutes per side of flushing, probing, etc.
failure to do so will plug your heat exhanger. no way to clean the shell side of the heat exchanger other than to replace it. making it a really expensive filter.
