8v 53N ? obsolete

[Docs Holiday]

Looking at purchasing a 43 Hat with 5,000 hours on 8V 53N motors. My Diesel mechanic says these
motors were leaky even after replacing gaskets and are now obsolete (parts not obtainable). Suggests do not purchase unless prepared to re-power. Has anyone had recent experience trying to get parts for these motors? Anyone had to re-power? If so what motors did you go to and did you have to change out transmissions?

 

[bostonhatteras]

Looking at purchasing a 43 Hat with 5,000 hours on 8V 53N motors. My Diesel mechanic says these
motors were leaky even after replacing gaskets and are now obsolete (parts not obtainable). Suggests do not purchase unless prepared to re-power. Has anyone had recent experience trying to get parts for these motors? Anyone had to re-power? If so what motors did you go to and did you have to change out transmissions?

My diesel mechanic owns a 38 hatt with those engines. The parts are there. do a search to see how many detroits of various incarnations are in service world wide. its at least a million units. That's a big market for all suppliers to ignore. If your mechanic is counseling against detroits, maybe he doesn't know how to work on them. There are a few very specific things particular to setting up detroits from rebuild or tune that a novice just cant know.

 

[SEVEN]

The amount of hours should tell you how old the motors were built. They all leak a little some more than others. Great motors in my opinion.

 

[jim rosenthal]

I don't think they leak too much if they're in decent shape and they have AirSeps or something like them. 5000 hours is not out of the question on DD naturals.

If the boat looks great and runs well and you can get it at a decent price, why not? You might get another thousand or two thousand hours out of them. As for repowering, of course it doesn't make any sense economically, but if you decide you really like the boat, why not?

The one thing to consider might be that if you have to resell it, with those hours it might not be an easy sell. It probably isn't right now, come to that.

 

[Walter P]

I think if the boat, which I assume is a 43 DC early vintage is in great condition and you really fall in love with it and it suits your needs now and for the foreseeable future, I would not hesitate to consider re-power with Reman Cummins engines. You can probably get the B series with gears somewhere in the 300 - 350 HP range for not too much money (plus installation). The advantages would be significant.... much better range (milage), much faster cruise because of the lighter weight and higher HP, much more engine room space and the list goes on. And by the way, if and when you decide to part with the boat, it would probably sell much faster and for more money. Granted you won't recover all of your cost for the re power but think of the pleasure etc you would enjoy. I'm not sure but I think the early ('71 - 73 or 4) with the 8-53's were only about 280 HP each and weighed a lot more than just about any modern diesel. Many of our forum members have repowered with the Cummins engines incl the B, C and 11 series and to the best of my knowledge they have been pleased with the result. Dr. Jim went through 2 repowers on his 36 and seem very pleased with his B series engines.

Walt

 

[Boatsb]

10,000 hours on them is not uncommon. More than that is.

I have a pair in my boat and have only had a few issues with parts. Mostly a week or two for shipping as they are not always stocked locally.

I buy all my gaskets and prints for the cooling system service 3 sets at a time and have no issues.


Overall they are loud, strong and almost no smoke. Easiest start of any Detroit's I've seen. Sure use trade them for 485 hp b series (6.7) engines in a minute but at almost $110k for new motors and transmissions it's a hard number to justify.

 

[Pascal]

10,000 hours on them is not uncommon. More than that is.

Overall they are loud, strong and almost no smoke. Easiest start of any Detroit's I've seen. Sure use trade them for 485 hp b series (6.7) engines in a minute but at almost $110k for new motors and transmissions it's a hard number to justify.

485Hp 6.7 B series ? AFAIK the B series tops around 315hp.

A factory reman 450hp C series with new ZF gear cost just under $40k At least it did a year ago when I bought mines The 315hp B series were $31k with gears.

 

[Boatsb]

B series goes up to 550 hp.

Then again what do I know about this. I just quoted a pair of them on a repower.

Waiting for the customers final decision.

 

[Walter P]

What is the displacement of the B series engines. 550 HP from such small engines seems likely only for short duration hard runs a few times and tear down and rebuild just like some race car engines. It has been commonly believed that more than one HP per cu in drastically reduces their useful lifespan between overhauls. The DD 6-71 TIB @485 is well over the displacement of 426 cu in and the engines get more stress than they were designed to bare, which is why a pair of 671 N's far outlast the 671 TIB. Am I missing something here?

I think the 315 HP B series engines would be an excellent choice for the 43 DC. Much more HP to weight ratio would probably make the 43 unstable. Yes I know that the 43 DC was available in 1979 with 390 HP 6-71's but considering the weight of the 71's against the B series Cummins, I would think one would be inviting erratic handling at high speed with much more HP from the relatively small and lighter B series engines. By the way, that issue came up after the '79 DC came out with 390 HP and beginning in 1980 Hatteras ordered the folks at Covington (one of the suppliers of DD to Hatteras) to reduce the HP output to only 325 HP. Of course the '79 model weighs more than the '80 and newer boats which would make them even more prone to broaching in certain conditions with the average skipper. Obviously all of us on this forum know how to handle our boats under any conditions safely...lol. I owned two 43 DC's ('73 model with 6-71 JT's @ 310 HP and an '80 model with 325 HP TI's by Covington) and the older boat was substantially heavier than the '80 model. I brought in Johnson and Towers to change the engines back to the higher HP and we estimated them to be somewhere about 410 HP. The boat was crazy fast for a 43 DC, at over 23.5 K WOT. It was a pretty scary ride in moderate seas and I hardly ever ran it over 20 K. Another BTW is that when I bought the '80 model the folks at Hatteras informed me of the lower HP and and I confirmed it and the reason for the HP reduction with someone by the name of "Red" at Covington.

Walt

 

[jim rosenthal]

B series engines are over 500hp now, because they are available in common-rail versions with much better control of injection patterns and electronic management of the CRFI system. They are also 0.8 liters larger.

I think the version I have, the 370hp, was the largest offered in mechanical injection. They are still available in the reman program. The QSB engines have been around long enough that they are also now in the reman program, too.

They are very reliable. Cummins has a very good rep on marine engines- they test them pretty thoroughly before putting them out on the market, I think.

You would not need 500 hp CR engines in a 43 MY, anyway. With 370 hp engines, and the diminished engine weight (easily a thousand pounds per side) she would go faster, burn less fuel, and run more quietly. I would be expensive, but you'd have a great boat when you were done. You would not have trouble planing, that's for certain.

 

[MikeP]

FWIW...I regularly glance at reviews of modern boats in the same size range as our 53 MY. What I find most interesting is that the fuel burn/speed ratio shown in the tests are essentially the same as the fuel burn in our boat with the OEM 8V71ti motors. YES, the modern boats/more powerful engines will achieve a higher top speed but at the same speeds from idle to 18 knots, the fuel burn on both is essentially the same.

 

[Avenger]

Not that the OP was really asking about repower options, but...

For a boat that size I would look at Cummins C series remans. 450 HP mechanical engines are much cheaper to start with, cheaper to maintain and at 8.3L they're not wrung out to make the HP like the 5.9/6.7 would be. There's plenty of room for them If they can fit 903s in there I'm sure they can fit Cs.

As far as overpowering, I don't think there's any risk of that in the engines we're talking about.

 

[krush]

Since we're spending other people's money, I say but a CAT c18 in it.


But really, since the original poster is boat shopping, have the patience and see if you can find a repowered boat with modern engines, if you actually go boating and put hours on it. If you are like most people and do 20-30hours or the annual trip to the fuel dock, then old detroits are fine...even if they are worn out.

the 8-53 will run forever. I have a 4-53 in an old truck, it's load, slow, but it can sit for 1 year in the field and starts up in 2 cranks every time.

 

[Boatsb]

Just for laughs.

The difference between NEW 6.7 550 hp b series and reman 600 hp c series was less than $5k.

Yes the 8.3 has more torque and more weight but either will do the job.

If I were making the decision I'd look at serviceability. Smaller engines mean more space in the DR.

My 41c would be easier to service with the b series. And at a 5000 hour estimated between rebuilds I'd not have an issue in my lifetime.

 

[SeaEric]

I have 8v53's in my 41 TC. They were not my first choice of power but that's what she has. My mechanic is Tom Hug and he has had no problem getting anything we have needed. Repower cost is totally prohibitive. FWIW there is a 43 DC for sale in Delaware with Cummins B series at a very attractive ask price. If you want that model with modern power - she's a good start.