DD Kits Source

[spartonboat1]

I am now committed to an in-frame overhaul this Fall on one of my J&T 6-71N, circa 1972 (the other has already been done). My tech has an un-named parts source from 'somewhere in FL', which is priced at $1,360 for kits, bearings, and gaskets. I have a quote from WW Williams for their equivalent parts group for about $2,500. I don't mind going the extra $1,200, if their is a significant difference in quality, but in what manner is it possible to learn how many vendors, sites or firms are there really, that make/mfg. these kits.

I assume that in FL and TX and worldwide, there are 1,000's, maybe millions of these old 71 series engines around. So since one kit fits the 3, 6, 8, and 12-71 engines, machining a continuing run of kits is probably is a single setup that runs continuously or frequently; one of the beauties of the old 2 cycle DD's. Then the parts group varies only by the gaskets, and somewhat by bearings.

So does anyone have an opinion, short of going to diesel.com, as to any one or more vendors being really superior, e.g. Williams, etc., in the cyl kits they offer?

 

[Boatsb]

Federal makes decent parts but "unnamed" is not a familiar brand to me.

If it is a company with a solid reputation I would consider it. If it's not you may be less than happy in the long run.

 

[spartonboat1]

Federal makes decent parts but "unnamed" is not a familiar brand to me.

If it is a company with a solid reputation I would consider it. If it's not you may be less than happy in the long run.

True, Federal has always made good parts, esp. bearings. Do they make the cyl kits as well (I haven't searched yet)? That would be interesting!

P.s., my next step shortly is to get the name of the 'un-named' parts source.

 

[Boatsb]

I know the local DD guy has sold federal parts when the DD is on eternal back order.

 

[captddis]

The FP kits will be fine on your naturals.

 

[saltshaker]

Some aftermarket stuff is good others are junk. One of the aftermarket manufacturers (Ithink it's either Federal or FP) offers a warranty that includes labor if one of their kits fail. Do some research and find out what the good Detroit mechanics are using. I always prefer going with Detroit factory parts but many have good results with some of the aftermarket stuff. Detroit kits have gone up a bit over the last year. I think the savings can be around $200 per kit for the good aftermarket kits. Be careful using the aftermarket heads. I've heard some of the machining was a bit sloppy on some.

 

[Boatsb]

Different engines require different parts. I know there is a difference between a natural and a turbo kit even with the same manufacturer. Cummins has different materials for pistons depending on the engine spec for the same block.

 

[spartonboat1]

I went on-line late last night and researched parts sources, esp. Federal, which markets kits under the name "FP Diesel". They make it sound as if they crank them out (kits) like popcorn with all computerized processes, which really has been the common mfg. mode for the last 15-20 years. Their line is marketed through a number of sources and sounds like a good product to me.

I did find some overseas products, which sounded 'ok', but did not inspire the confidence that FP does. I also researched MTU (DD parts), but they seem less aggressive than other suppliers, at least their website content is not as robust, plus no on-line pricing.

So based on this thread's response, my on-line research and another post on the HOF (what a good resource-- HOF), FP Diesel sounds like the indicated direction. Finally, someone on the other legacy thread mentioned doing certain seals, e.g. the blower, so I will discuss that with my tech as well.

Thanks for the responses and the HOF legacy postings!

 

[Walter P]

About 25 years ago, I rebuilt a pair of 6-71 JT's (310 HP). The kits were bought from a local DD dealer and worked well. Well there are actually different kits for naturals and for turbo engines. The N's will be approx 22-l comp ratio while the Turbo versions are approx 17-1. I guess the reasoning was not to blow the turbo engine up with too much pressure. A few years later I was told by several DD guys that it had become fairly common to use 22-1 kits in the turbo engines. They claim they worked well and the engines started up easier etc...etc.. I would think that to second guess the folks who designed these beasts would be risky but I guess it worked out. Anyone else ever hear or this?

Regarding the manufacturing of the kits.... I'm certain that like many things out there, the old saying "let the buyer beware" should be kept in mind. Remember that if you want nice fresh clean Oats of first quality, they cost X $ per lb. If you are satisfied with Oats that passed through the horse before, they are probably a little cheaper.

Walt

 

[Avenger]

22:1 ??? Indirect injection Detroits???? I'm fairly sure the naturals were 18:1 or thereabouts. There really isn't that much difference, and with the motoryacht crowd running at hullspeed most of the time they might as well be naturals anyway, so putting the higher ratio kits in just makes sense.

Clevite was another vendor to the OEs. In the past we've had good luck with their products. I think they're owned by Mahle now. Mahle is probably the biggest maker of pistons in the world.

 

[spartonboat1]

22:1 ??? Indirect injection Detroits???? I'm fairly sure the naturals were 18:1 or thereabouts. There really isn't that much difference, and with the motoryacht crowd running at hullspeed most of the time they might as well be naturals anyway, so putting the higher ratio kits in just makes sense.

Clevite was another vendor to the OEs. In the past we've had good luck with their products. I think they're owned by Mahle now. Mahle is probably the biggest maker of pistons in the world.

Yes, thanks, I did see Clevite/Mahle as one of the parts sources. I definitely remember Clevite as a long time OE bearing vendor. That seems to make three legitimate sources of parts: DD/MTU, FP Diesel, and Clevite/Mahle.

Thanks very much for the Clevite update!

P.s., found a website regarding Federal's bankruptcy back in 1997. But that is quite some time ago, so I assume (??) that has been somewhat resolved, or they would not be flying their flag at this time.

 

[saltshaker]

22:1 ??? Indirect injection Detroits???? I'm fairly sure the naturals were 18:1 or thereabouts. There really isn't that much difference, and with the motoryacht crowd running at hullspeed most of the time they might as well be naturals anyway, so putting the higher ratio kits in just makes sense.

Clevite was another vendor to the OEs. In the past we've had good luck with their products. I think they're owned by Mahle now. Mahle is probably the biggest maker of pistons in the world.

Not sure if the same holds true for a natural kit vs a turbo kit but I looked at a boat that had 12V92DDEC's in it. She was very hard to start and smoked like mad. Engines were reported to be low hour rebuilds. I mentioned this to the mechanic who was working on my boat. He used to work for JT and said if you put a standard 92 series kit in a DDEC 92 they will smoke, be hard to start and need majors prematurely. The DDEC's are 15:1 compression and the mechanical 92 turbos are 17:1. Claims they had to rebuild several that used the wrong kits.

 

[Avenger]

I'm pretty sure there's only a 1 pt difference between the turbos and the naturals on mechanical engines. I should have used a to make it clear that I was kidding about putting the natural kits in a turbo. It was just a poke at the hull speed cruising club. I wouldn't build an engine out of spec unless I had good reasons to and a lot of information and money to work with.

 

[captddis]

Actually we did put 18:1 kits in a TI engine and it worked out very well and still going strong 15 years later.

Like Jack said the DDEC's use 15:1 kits and were not available from aftermarket sources. If you have one of the 6V92TIA 625hp engines they take a special kit and a special big pin rod.
All the DDEC's also come with blockheaters....

 

[spartonboat1]

Yes, thanks, I did see Clevite/Mahle as one of the parts sources. I definitely remember Clevite as a long time OE bearing vendor. That seems to make three legitimate sources of parts: DD/MTU, FP Diesel, and Clevite/Mahle.

Thanks very much for the Clevite update!

P.s., found a website regarding Federal's bankruptcy back in 1997. But that is quite some time ago, so I assume (??) that has been somewhat resolved, or they would not be flying their flag at this time.

Contacted the Tech today, who gave me the name of the proposed DD kits vendor: Dieselpro.

They do show TwinDisc as one of the products they support, but there is no information that I can see regarding their kits production sources, probably other than plants they may own, control, or have some type of relationshipship. Could be mfg'd in Mexico or China for all I know; nothing about mfg source on their website that I could see.

I think I'll ask the tech to switch to FP Diesel or Clevite, since I am more familiar with the brand names and as the prices seem competitive with DieselPro, while MTU/DD is a $1k higher than the others.