detroit 6v53 power on hatteras

[scubajohn]

i would like to know if the 653 is a good sorce of power for a hatteras 40 ft
they are in the boat so iwould like to keep them.

what would the cruise be and what about fuel consuption they are rated 210 hp each

any help would be great thanks john

[Ike]

The Coast Guard has used the 6V53 engines in their 41 foot utility boats for many years with great success. Someone else will have to tell cruise and fuel consumption. I managed a CG industrial facility where we overhauled engines and the 6V's went at least a 1000 hours (that's ten years for the average boater) under really hard use (Used and abused is more like it) between overhauls. Of course the Coast guard can put that many hours on an engine in less than couple of years. They were very rugged and reliable

[FAST FRED]

what about fuel consuption they are rated 210 hp each

An antique design (1936) that is Very reliable and would definatly be worth keeping.

These engines NEED to be loaded at 60% or more to be efficent, less than 60% does not reduce the fuel burn by much.

A Gal an hour will give 16 hp if properly set up, so running at 125hp or so will cost about 8 gph per engine.

New engines with electric injection , turbos and intercoolers MAY get 22 to 24 hp from the same gallon of diesel.

But paying for the swop would require hunderds , or thousands of hours of operation , just to brake even.

Keep what you have , but DO remember Detroits use 40wt CF-2 lube oil , and multigrade will kill them DEAD!

FAST FRED

[scubajohn]

thanks for the info guys i feel better about them now and a big thanks on the oil does this aplly to all diesles or just detroits anyone have a guess on speed 41 ft hat fishing boat

[stevel]

Originally Posted by scubajohn

thanks for the info guys i feel better about them now and a big thanks on the oil does this aplly to all diesles or just detroits anyone have a guess on speed 41 ft hat fishing boat

This applies to 2-stroke diesels. Something about being in a 2-stroke diesel makes multi-viscosity oils want to shed polymers. My dad wouldn't listen to that advice, ran Rotella (a fine product for it's intended use) in his 8v71 and ended up ventilating the block with a connecting rod.

My single 6v53 runs great in a 26' personnel boat, and gets the same fuel consumption numbers that have already been mentioned.

[Corpus Skipper]

From my experience, an older (heavy) 40' Hat with 6-53s should run about 19-21 kt. wide open with a moderate load, and cruise 15-17 kt, at about 16-18 gph total, 25 gph total at wot.

[williewiskers]

"From my experience, an older (heavy) 40' Hat with 6-53s should run about 19-21 kt. wide open with a moderate load, and cruise 15-17 kt, at about 16-18 gph total, 25 gph total at wot."


I have an OLD (1961) Uniflite 42' and 6v53n engines and Im having a hard time matching props to my boat. Based on your experience with your 40' Hat, what props were you using to get the numbers referenced in the cited post?

I have run it through all the calculators and called prop shops, but the answer isnt clear.

Loaded weight= 52000#
waterline length= 39'
length= 42' (45' LOA w/ pulpit and platform)
shaft dia= 1.75"
shaft material= naval brass (some corrosion)
two engines= 216 HP S.A.E. HP each (210 at shaft)

borg warner velvet drive transmissions assumed to be 2.10:1
(@ 2.10 ratio the max SAE HP is 250 with safety factor of 2 and naval brass shafts @ 1.75")
(@ 2.57 ratio the max SAE HP is only 205 with same shafts)

1.91 ratio trans's wouldnt be an appropriate ratio and the 2.57 is too much for the shaft, so I assume 2.10:1.



On the whole internet, you are the only one who seems to have something close to what I have that actually seems to know something about it.


Thanks for your reply

Chris
Lincoln Harbor
Weehawken, NJ
Hudson River

[gonzo]

Those old Detroits will leak oil. It is an ongoing problem with them. The solution is to install a drip pan under to prevent the oil from spreading throughout the boat.

[stevel]

They are just marking their territory.

Originally Posted by gonzo

Those old Detroits will leak oil. It is an ongoing problem with them. The solution is to install a drip pan under to prevent the oil from spreading throughout the boat.

[gonzo]

That's one way to make yourself feel good about the oily territory surrounding a DD

[FAST FRED]

The old truckers motto

"
IF Detroit Diesel made bricks ,
they would be green,
And LEAK OIL!

FF