| |
Bertram31.com General Bulletin Board
Re: ? for Capt Dave K.
Posted By: Capt. Dave Kosh In Response To: Re: ? for Capt Dave K. (Scott)
Date: Wednesday, 14 September 2005, at 10:04 a.m.
John,
I'll send you a cad drawing of the system that I use. It is pretty simple. "T" off with a 3 way bronze ball valve right before the transmission oil cooler sea water goes into the exhaust. Now the valve will be a "Normal" position as you are currently using and a "Flush " position which the faucet water is induced and backflushies the entire system and exits via a pea hole in the engine raw water pump housing. I have Jabsco raw water pumps on the Volvos but most have that little pea hole which works great for exiting water. The exiting backflushed water in turn goes to another 3 way valve for either port or starboard flush water diversion to a through hull which goes in the canal. It works great! Just don't forget to put your first diversion valve back to the "Normal " position after your done flushing (5 minutes per engine)
I elected to do it this way instead of using automatic check valves which would eliminate the first diversion valve but also risk blowing an impeller if it fails so that is just my personal choice. Most systems nowadays use the automatic check valve but they are usually put on outboards.
After I run fresh water for 5 minutes on each engine I inject Saltex (or equivilant chemical) into each engine for 15 second per engine.
My cooling systems after 5 years and 800 hours look excellant. I do replace the zincs evey six months however. They usually show much life left but I replace them anyway except my after cooler one I just brush it off as it seems to have less loss and they are much bigger.Volvo factory now recomends to backflush the engines as well. Zincs only take care of the galvanic corrosion (which is higher in salt water because it has greater conduction)Leaving salt water lay(even though most drains out)in your cooling system is only a time bomb. Copper componants don't like saltwater especially when it dries out which it does after draining after it's shut down. Wet salt water is almost harmless. It's when it drains and dries . That's the culprit.Now the only part that you can not back flush is the exhaust elbow unless you have a way to get into yours, most don't. Backflushig also will remove any small impeller fragments left after a blown impeller ordeal. Not big pieces but little ones which are more harmfull and get sucked into the cooling tubes.
Second thought it may be just as easy for me to mail you the print on my install. Give me your mailing address.
Hope this helps.
I just got Windows 2000 Prof. installed in my PC so I was down for a day other wise my response would of been quicker.
Dave K
| |
Bertram31.com General Bulletin Board is maintained by Patrick McCrary with WebBBS 5.12.