Fluid Replacement Recommendations

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knitchie
Posts: 27
Joined: Mon Nov 09, 2015 4:30 pm

Fluid Replacement Recommendations

Post by knitchie »

New owner of Hull #447; first diesel. We are on Lake Champlain in VT, but will likely move down the coast in a few years. Not knowing the maintenance schedule for the boat, I plan to replace all the fluids, filters, impeller and belt in the spring. What is recommended for fluids?

Engine oil: I see Rotella T 15W40 recommended generally for marine diesels
Transmission oil: Is Foley Hytork Fluid ($40/qt) worth 3x Red Line D4 ATF ($13/qt)
Coolant: Anything special?

I read all sorts of things about not mixing different oils, not sure why, but plan to flush and fill twice. Is that a waste of money and time?

Fair winds,
Ken
Flagmanmike
Posts: 25
Joined: Fri Mar 27, 2015 10:42 am

Re: Fluid Replacement Recommendations

Post by Flagmanmike »

From my engineering days I learned that each oil manufacturer has a unique/specific set of additives for each grade of oil. The fear is that some of the additives from different blends may react in a negative way such as causing sediment and removing the beneficial additive from the oil. As a side note, as the runtime on the oil increases, the amount of additives decreases by "burning" off or by degradation. In my opinion, It is always best to stick with one blend/manufacturer/grade. Better safe than sorry.

Mike Cronin
Flagship, Hull 314
KevinMc
Posts: 85
Joined: Sun Sep 08, 2013 5:36 am

Re: Fluid Replacement Recommendations

Post by KevinMc »

For the coolant I use the standard diesel engine "red" coolant you can get at most truck stops. The standard big box and even auto parts stores may not carry diesel engine coolant but I've always been able to fine the pre-mixed 50-50 coolant at truck stops along the interstate.
Kevin
#59
NavSta Norfolk Marina
tranquil
Posts: 109
Joined: Fri May 30, 2008 10:07 pm
Location: chicago

Re: Cooland Replacement Recommendations

Post by tranquil »

Greetings

Approximately how much Dex-Cool or similar red coolant for diesel engines is needed to refill the system after it is drained and flushed? It is a quart, few quarts, gallon, etc,? I cannot find this information in the engine manual for the Universal 35 MB

Thanks

Teri
Teri Weber
Tranquil
Hull #187
Chicago
Tranquilcat42@yahoo.com
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Olivia Mae
Posts: 94
Joined: Wed Nov 14, 2018 1:19 pm

Re: Fluid Replacement Recommendations

Post by Olivia Mae »

Don't use Dexcool. Peak Final Charge Global is a good heavy duty diesel choice. You can probably find it at Walmart or a parts store. You'll need 2 gal.
Scott and Linda

Olivia Mae
C350 Hull #53
Erie, Pa.
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Olivia Mae
Posts: 94
Joined: Wed Nov 14, 2018 1:19 pm

Re: Fluid Replacement Recommendations

Post by Olivia Mae »

To the OP, Dexron transmission fluid only in that transmission. You need the older Dexron before they changed it to synthetic. The only place I can find it now is at NAPA stores. They sell it as "Dex/Merc". Our transmission rebuilder was adamant about this. Also change it every time you do an oil change
Scott and Linda

Olivia Mae
C350 Hull #53
Erie, Pa.
Bob_A
Posts: 72
Joined: Tue Jan 26, 2021 7:24 pm

Re: Fluid Replacement Recommendations

Post by Bob_A »

I use the following: HD expert premium 50/50 engine coolant 6 quarts, Shell Rotella T5 SAE 15W-40 four quarts, Mobil Dexron -V1 ATF 560 - 580ml
I change oil, filter and trans fluid every 100 hrs max and again at the end of the season. All three fuel filters one a year. 2000 engine / trans hours and runs beautifully. I am gentle with it and find a sweet spot at 2300 rpm. But I am going to look into this Dex/Merc trans fluid mentioned.
Bob & Cherie
Cheeky Monkey - Hull 363
Vancouver, BC
KenKrawford
Posts: 614
Joined: Wed Nov 02, 2005 8:54 pm
Location: Atlanta, GA

Re: Fluid Replacement Recommendations

Post by KenKrawford »

Bob, what method are you using to get 580ml of transmission out? I can never get more than about half that much.
Ken Krawford
Message Board Moderator
C350 # 351
Lake Lanier, GA
Bob_A
Posts: 72
Joined: Tue Jan 26, 2021 7:24 pm

Re: Fluid Replacement Recommendations

Post by Bob_A »

Hi Ken,

560ml is the amount I see recommended but I always find it a bit less than full. Too full = very bad.
After all sorts of small manual extraction pumps I have settled (for now) on a large medical syringe. About 1" diameter and 6" long from most drug stores. These have enough friction seal to hold the fluid in the syringe and tube so you can get back to a disposal container as it will take a few times.
I have tried all sorts of variations like an 10" semi rigid plastic tube and went in through the top cover but last time I used a longer flexible tube (maybe 18") with a semi rigid piece on the end. The end entering the dipstick hole.
Semi rigid (even rigid) seems to get easily down to the bottom of the trans case where the flexible does not. This last time I got on hands a knees and went through the small port side access door on the engine enclosure.
Make sure that the semi rigid is longer than the depth of the trans in case it comes off the longer flexible tube. I sometimes use a small "wing" of masking tape on the tube so it cant drop in.
I discharge the syringe contents into a measuring cup and I do get pretty close to 560.
I am going to experiment with a small drill mounted pump next.
Bob & Cherie
Cheeky Monkey - Hull 363
Vancouver, BC
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