REBrueckner
Legendary Member
- Joined
- Apr 24, 2005
- Messages
- 4,168
- Status
- OWNER - I own a Hatteras Yacht
- Hatteras Model
- 48' YACHT FISHERMAN (1972 - 1975)
Following for 1972 8V71TI's
I'm sure somebody has posted similar before, but I don't remember seeing such and thought others might find it helpful. Total elapsed work time: either one long workday or a day and a half for the more sane owner.
Testing my antifreeze with test strips this past fall I found nitrites were low and so I decided to change the antifreeze entirely as it has been a while...ten years!!!!! ...(yea, I know, NOT classic maintenance procedure!!!)... However, before you judge too harshly and blast me read the rest.....
Two years ago it tested ok.... Nitrites are especially important for cavitation corrosion protection in wet liner engines (53 series and 92 series Detroits, not important in 71 series like mine which are dry liner). I now suspect any low silicate antifreeze is ok in 71 series, but I am NOT going to test that theory...I use only HEAVY DUTY Detroit Diesel spec approved antifreeze...
The prior antifreeze I used was an odd one unavailable now (but which met DD coolant specifications I outlined in other posts ) and which cost only $2 /gal ten years ago as a left over after the winter season. The last of the original containers had a bit of gel formed (maybe two small glops per container) reflecting limited shelf life but I just used the top 3/4 of each container when refreshing my engines at 1 gal per year recently. Anybody know how any "glop" can form in a low silicate antifreeze???
Draining the old stuff : It was clear green all the way, I never did see anything even slightly suspicious and I sampled the intial coolant drain from each engine four or five times to see if any "crud" was in the cooling system....there was none.. running my finger down inside the coolant fill cap into the expansion tank revealed no slime, just a bit of slippery tannish/brown coolant residue (the tan/brown reflecting typical superficial rust corrosion and icky coolant feel).
Frankly I was surprised everything was so incredibly clean and clear (even though I had added a gallon of fresh antifreeze and water annually to keep it "refreshed").
I ended up draining into the bilge, then pumping from there to containers....it was incredibly time consuming trying to catch fluid from individual petcocks one at a time in small containers which would fit under...I gave up after over four hours on one engine!!!!....
Each 1972 8V71TI took a total of about 13 gallons of coolant total ...half antifreeze and half distilled water. I did NOT drain the port side block of either engine as the petcock is so close to the starter I could barely reach it...and figured splashing coolant all over the starter was not within my repetoire of skills. (maybe a half gallon of coolant remained in there judging from the stbd side engine block drain???)
I drained coolant using these petcocks (after removing the radiatior fill cap): at the bottom of the coolant circulation pump discharge pipe, bottom of the oil cooler(right nearby), aft stbd side engine block, rear of each exhaust manifold....five total....These are identified in my DD manuals...Operations and Maintenance.
I also removed my overflow tanks and emptied and cleaned each one by hand..there was some rust residue at the bottom....not enough to measure..a thin film layer in corners....had not cleaned them in a bout three years.
I preheated each engine for easy start and ran each for about five minutes until coolant in the expansion tank was warm (not hot); (coolant circulates slowly even with thermostats closed); drained the antifreeze into the bilge; filled the engine with plain water via a hose...ran again til warm, drained; repeated a second time: drain, water fill,run, drain....First drain coolant had a tiny bit of old antifreeze...was just a bit slippery....second drain had ever so slight green antifreeze tinge, but I could not feel any rubbing wet fingers together...
Final fill:added alternately 1 gal Power Cool followed by one gallon distilled water till full to top...ran engines about ten minutes; lube oil was nice and warm (not mad hot), so I drained and changed it.
I'm sure somebody has posted similar before, but I don't remember seeing such and thought others might find it helpful. Total elapsed work time: either one long workday or a day and a half for the more sane owner.
Testing my antifreeze with test strips this past fall I found nitrites were low and so I decided to change the antifreeze entirely as it has been a while...ten years!!!!! ...(yea, I know, NOT classic maintenance procedure!!!)... However, before you judge too harshly and blast me read the rest.....
Two years ago it tested ok.... Nitrites are especially important for cavitation corrosion protection in wet liner engines (53 series and 92 series Detroits, not important in 71 series like mine which are dry liner). I now suspect any low silicate antifreeze is ok in 71 series, but I am NOT going to test that theory...I use only HEAVY DUTY Detroit Diesel spec approved antifreeze...
The prior antifreeze I used was an odd one unavailable now (but which met DD coolant specifications I outlined in other posts ) and which cost only $2 /gal ten years ago as a left over after the winter season. The last of the original containers had a bit of gel formed (maybe two small glops per container) reflecting limited shelf life but I just used the top 3/4 of each container when refreshing my engines at 1 gal per year recently. Anybody know how any "glop" can form in a low silicate antifreeze???
Draining the old stuff : It was clear green all the way, I never did see anything even slightly suspicious and I sampled the intial coolant drain from each engine four or five times to see if any "crud" was in the cooling system....there was none.. running my finger down inside the coolant fill cap into the expansion tank revealed no slime, just a bit of slippery tannish/brown coolant residue (the tan/brown reflecting typical superficial rust corrosion and icky coolant feel).
Frankly I was surprised everything was so incredibly clean and clear (even though I had added a gallon of fresh antifreeze and water annually to keep it "refreshed").
I ended up draining into the bilge, then pumping from there to containers....it was incredibly time consuming trying to catch fluid from individual petcocks one at a time in small containers which would fit under...I gave up after over four hours on one engine!!!!....
Each 1972 8V71TI took a total of about 13 gallons of coolant total ...half antifreeze and half distilled water. I did NOT drain the port side block of either engine as the petcock is so close to the starter I could barely reach it...and figured splashing coolant all over the starter was not within my repetoire of skills. (maybe a half gallon of coolant remained in there judging from the stbd side engine block drain???)
I drained coolant using these petcocks (after removing the radiatior fill cap): at the bottom of the coolant circulation pump discharge pipe, bottom of the oil cooler(right nearby), aft stbd side engine block, rear of each exhaust manifold....five total....These are identified in my DD manuals...Operations and Maintenance.
I also removed my overflow tanks and emptied and cleaned each one by hand..there was some rust residue at the bottom....not enough to measure..a thin film layer in corners....had not cleaned them in a bout three years.
I preheated each engine for easy start and ran each for about five minutes until coolant in the expansion tank was warm (not hot); (coolant circulates slowly even with thermostats closed); drained the antifreeze into the bilge; filled the engine with plain water via a hose...ran again til warm, drained; repeated a second time: drain, water fill,run, drain....First drain coolant had a tiny bit of old antifreeze...was just a bit slippery....second drain had ever so slight green antifreeze tinge, but I could not feel any rubbing wet fingers together...
Final fill:added alternately 1 gal Power Cool followed by one gallon distilled water till full to top...ran engines about ten minutes; lube oil was nice and warm (not mad hot), so I drained and changed it.
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