Re: Flushing saltwater blocks
i can help you.
salt away wont help your overheating problem. the number one and two reasons saltwater engines, or fresh for that matter, run hot is
1. the impeller in your sea water pump is falling apart, have to replace it every year, and you would be supprised how many people dont. salt water is harsh on rubber.
2. the thermostat. every other year for that one. it doesnt take much for that puppy to freeze up from corrosion.
you should also remove and inspect the risers for corrosion. will need two gaskets, so get them before you do. in salt water, they are trashed after 4 or 5 years, shoud be replaced every 3 to 4 years, and inspected every year. they are the number one reason for saltwater intrusion, the heads are the number two reason.
now, for some disheartining horrible facts.
how old is the motor? if it is 8 years old or older, i dont care how pretty it is on the outside, and it doesnt matter if it has 50 hours or 500 hours, a salt water motor is rotten to the core. rusted beyond repair on the inside.
the good...and bad...news is, this rot wont be the problem of your overheating. long before the water jackets degrade enough to cause a problem with heating, the thin cast iron walls seperating the water jackets in your heads from your exhaust ports will develop pin holes and leak water into your cylinders and destroy your engine long before they get clogged up with rust.
dont worry about it untill you see some milkshake in yor oil, or, your starter starts to drag after itsd been sitting and you KNOW its not that old and you KNOW the batteries are in good shape. nothing you can do but hope for the best untill then.
replace the sea water pump impeller, and the thermostat. both are easy to do and cheap. should clear up your heating problem.
as far as corrosion prevention, ill give you a tip. on v8 chevys, there are two water drain plugs at the base of the block on either side at about the middle of the engine right at the top of the oil pan. 1/2 inch thread. starbord side should be right under the knock sensor if you have one.
remove them and replace them with 3/8 inch hose niples. attach some heater hose to bothh, runn them into a T fitting, then run them into a through hull flush fitting through your transon.
buy a multi purpose pump from the hard wear store and about 6 gallons of antifreeze, and 2, 5 gallon buckets with lids.
after you use your boat, and after you flush your engine, pump the remaining water out with this flush system, then pump your engine full of antifreeze. should take about 41/2 gallons. and when you want to use your boat, pump the antifreeze out of the engine and into the 5 gallon bucket. dont forget to secure the lid. dogs like the taste and it will kill them. you must secure the lid.
the damage is done when the boat is sitting, not when your running it. thats why 50 hours doesnt mean any more or less than 500 hours.
antifreeze is a corrosion inhibitor. it wont repair the damage, but it will keep new damage in check for a longer period of time.
sorry, but its the truth. and in your spare time, start looking for new long blocks. your gona need one sooner than later.
and i cant emphisize this enough, there is NO REBUILDING a salt water engine. the block is toast. the heads are toast. nothing wrong with putting in a gm rebuild, but a waste of time to rebuild yours. i know, i tried. was a fantastic failure. both of them flew apart within minutes of each other. the head bolt threads were so degraded from corrosion in the water jackets, they blew out the head gaskets, filled with water, then compresssion actually bent most of the rods.
ideling back to dock made people cringe form the sound of two big blocks slapping rods against the blocks. people at the dock actually walked quickly away when they herd me comming. the popping form the blown gaskets, slapping rods, and over reving just to keep them running to get back was an experience ill never forget. it was screaming "fear me", or, "im an idiot, run for your lives" not sure which.
