CMD tdi

[TailhookTom]

Now that Cummins Mercruiser Diesel is selling/distributing the former Volkswagen tdi series -- V6 and V8 high rpm diesels, any new thoughts from those wiser than me -- pretty much everyone can be considered that!

My usual considerations would be parts/service/reliability versus the bargain pricing. My understanding is this is a marinized version of the engine that is in the VW/Audi SUV and the Audi A8 -- which typically makes me nervous -- what is designed for land use usually works best in land use.

However, size and weight make a pair look like a nice alternative to Yanmars, Styers and Cummins. I beleive they make 350hp out of 800+-pounds in the V8 and 250 in the V6. Both of which would fit nicely in a B31.

[In Memory Walter K]

Tom- I would be interested in the responses, but remember, the Cummins B series were born of their success as a Dodge truck engine. Also, although the high hp/weight ratios on some of these engines sounds good (and they are), a heavier weight seems to have a positive influence on how our B-31's ride.

[bob lico]

tom don`t get nervous . yanmar 315hp stp is a toyota engine marinize. cummins 6bta originally came from there 6b block used in generators catapillar 3126 came from 3116 which came from there truck engine.honda outboard engine is from there car engine.the list goes on.

[Bruce]

Parts and service is the key as 99.9% of Merc dealers don't have a diesel mechanic on staff because there isn't enough of these engines out there.

Been doing this to and fro with Merc for over 25 years with their diesel conversions. NONE ever lasted.

When Yanmar contracted BMW to supply an engine to replace the 4lh, I reminded the powers that be of Mercs failed relationship with BMW marine diesels years prior. Nobody as usual listened to me.

Yanmar America basically has SFB's.

The first batches had a tendancy to catch fire. ooooops..........

[TailhookTom]

Bruce:

Would SFBs translate as Slop for brains? Or a close varient thereof?

Tom

[Bruce]

Pretty close.

[Rocket]

I have 7 VW diesels in my Linde forklifts. I can't speak for the higher HP motors, but I hope the marinized version has an improved timing belt. If belt and idler are not changed at 1500 hours, at 2,200 you buy a new motor, cheaper than rebuilding. We have had 2 blow up on us and I can confirm that it is an interferance engine. We had one where we had the dealer do the 1500 hour change, the idler was missing from the kit so they left it and about 100 hours later, new cylinder head and valve train. The next repair lasted 200 hours, here's cheering for more! I would not put one in a boat after my experience. I have about 30 cummins motors running in trucks and we have had minor injector problems and the usual spate of oil leaks, but very good reliable motors in ISB, ISL and ISX in my experience. I am going to all electric forklifts, by the way!

[coolair]

Thats funny, i was about to ask about these. I spoke to a boat yard to day about doing some work on my boat, and i mentioned i would like to run diesels, but at 70k cant justify it. he say.. well it would probably only cost 40, i just purchased several NOS cummins/mec that are 320hp.
I said very interesting but they are 2008 and no warranties still in crate.

[Dug]

Tom,

I have a 2005 VW Touareg. It has the 310 hp V8 that is also the engine for similar vintage Audi A8's. It is silky smooth, strong power, and knock on wood I have not had any engine problems with 126,000 miles or so thus far. Its a great engine.

Marinized however, I know it may not be the same, and you cannot just pull into a vw or audi dealer with the boat...

D

[TailhookTom]

Dug -- obviously you have never seen me dock a boat!