What’s the worst marine diesel

[GordMay]

Originally Posted by MicHughV

Now that skipperpete mentioned the seagull engine, I have to move the VP into second place. How that seagull engine managed to run in the first place is mystifying. It is, in the end, a classic piece of British engineering, that must date back to prehistoric times.

The Seagull outboard was an excellent engine, for the boating enthusiast, who wanted to learn, how to row.

[skipperpete]

Wottie, your Arona was just one of a memorable flock of disastrous Diesel engines from Italy...... I just don’t know how all those engine makers got it so wrong. Lombardini, Arona, Ruggerini, VM Motori, and they’re only the ones I can recall without doing an online search, I know there were more.... Isotta fraschini and Fiat both did marine conversions and the Fiat diesels were pretty good, trawlers here on the OZ east coast used em successfully for a while, initially because they were cheap but they proved to be a reliable power plant over time.

[kenbo]

Originally Posted by s/v Jedi

No, you had the MDIIB and I had the MDII. After yours came the MDIIC

I believe the confusion comes from you stating your MD2 had 25hp. The MD2 had 15.5hp and the MD2B had 25hp.

[s/v Jedi]

Originally Posted by kenbo

I believe the confusion comes from you stating your MD2 had 25hp. The MD2 had 15.5hp and the MD2B had 25hp.

Is that so? It was 15hp with a two cylinder?! I’m sure ours was 25hp. Had to crank for ever.

[MicHughV]

Unless it will be immediately replaced I will not buy a boat with a Volvo in it.

My sentiments exactly. I had two of 'em at one time, as if, having one wasn't punishment enuff.

[jamhass]

My VP-2003T ... everything Volvo made to marinize that thing wanted to turn to sand, literally. Who else would have thought to make heat exchangers out of copper and aluminum? And put them in a saltwater environment ...

[skipperpete]

Originally Posted by jamhass

My VP-2003T ... everything Volvo made to marinize that thing wanted to turn to sand, literally. Who else would have thought to make heat exchangers out of copper and aluminum? And put them in a saltwater environment ...

The Volvo 2003T is not a good engine for all the reasons you mentioned and more, but again, some folks report getting years of reliable service from them For me they sit at about an equal second place alongside Lombardini...... but well behind the notorious GM Detroit 8.8 fuel pincher...... #1 on my list of duds.

[kenbo]

Originally Posted by s/v Jedi

Is that so? It was 15hp with a two cylinder?! I’m sure ours was 25hp. Had to crank for ever.

Not to be pedantic but I worked on these engines back in my wasted youth, and the MD series IMO were great engines save for raw water cooling and the cost of parts. It's also not uncommon for a 2-cylinder diesel to rate at about 15-18hp. Yanmar GMs and the Mitsubishi LE series come to mind.

Volvo's specs for the MD2 were 15.5hp @ 2300rpm and the MD2B was rated at 23hp @ 2500rpm. The only significant difference between the two was the bore size. Volvo increased the bore from 79.37mm to 88mm and ran the rpm up a couple of hundred revs most likely for marketing purposes. I'd attach the workshop manual for reference but the file size exceeds the attachment allowance.

[SomeGuyInaShirt]

Originally Posted by s/v Jedi

I had a Volvo Penta 25hp 2-cylinder that I hated because it started only after 30 seconds cranking or so.

Agreed! I had a 1975 Volvo Penta MD11C And it was absolute trash. I'm sure if new spare parts were still available it would be fine but all I could get were used parts at triple the price of comparable parts for respectable engines. Volvo will never see another dime from me, absolute trash company.

[boatman61]

MD2B.. best engine ever, simple, easy to maintain and never a worry if your batteries died.
Had one in my old Longbow and loved it..

[s/v Jedi]

Originally Posted by kenbo

Not to be pedantic but I worked on these engines back in my wasted youth, and the MD series IMO were great engines save for raw water cooling and the cost of parts. It's also not uncommon for a 2-cylinder diesel to rate at about 15-18hp. Yanmar GMs and the Mitsubishi LE series come to mind.

Volvo's specs for the MD2 were 15.5hp @ 2300rpm and the MD2B was rated at 23hp @ 2500rpm. The only significant difference between the two was the bore size. Volvo increased the bore from 79.37mm to 88mm and ran the rpm up a couple of hundred revs most likely for marketing purposes. I'd attach the workshop manual for reference but the file size exceeds the attachment allowance.

Originally Posted by boatman61

MD2B.. best engine ever, simple, easy to maintain and never a worry if your batteries died.
Had one in my old Longbow and loved it..

Yeah no wonder after hearing the stories about English engines… the VP must have been amazing

[Bowdrie]

Originally Posted by boatman61

MD2B.. best engine ever, simple, easy to maintain and never a worry if your batteries died.

Haha, a couple of long time friends of mine might argue with each other over their engines.
One has an MD2B that is quite dependable, the other has a one-cylinder Sabb of ~10Hp.
The MD2B I can relate to, I think the Sabb is from the dawn of the Industrial Age, but it runs like a Swiss watch.
Probably neither of them belongs in the category of "worst" engines.

[Tupaia]

Originally Posted by skipperpete

I worked on MD17C’s a long time ago those engines had a few interesting issues but really good bones. The injector sleeves seemed to leak a fair bit and it was counter intuitive to have the flywheel on the front (and what a flywheel it was). Putting a rubber plug on the engine oil filled gearbox housing seemed unusual but apart from my antipathy toward raw water cooled engines I think overall they were one of the better, maybe even the best of the small Volvo range.
Cheechako, did you mean the VW golf or Passat engines? It’s amazing how many VW engine models have been converted to marine use up to around 200hp. The single most perplexing boat and generator engine for me is the compact Lombardini FOCS and I read a post on this forum once that suggested these were originally VW engines. How Lombardini (and now Koehler) ever thought it was a good idea to include so many fragile new innovations in a a small highspeed Diesel is a mystery , this is the one engine I would suggest replacing rather than repairing and is close to the top of my list. I’ve had very little to do with BMW marine engines other than to replace water pumps and heat exchangers so I can’t applaud or condemn them.
Does anyone have experience with STEYR engines?

The base engine for Lombardini is Fiat and they have produced more of these than any other engine maker combined. The pinnacle of Italian engineering, low weight, high performance and female. Looked after they are great, neglected expect to get divorced. Parts come under the category of "ci vediamo domani"

The primary issue with most modern engines is not the engines themselves but all the emission modifications that are imposed upon us by politicians and of course biodiesel.

In all honesty I hate all diesel engines. I ran two Dolphin 16hp PETROL engines, electronic ignition, 2 stroke, dry sump, raw water cooled with shaft drives. Required a box of spark plugs and some spare air filters. No oil changes just a once over with an oily rag. Those were the days.

[VChild]

Originally Posted by Jim Cate

I'm a bit surprised at the negative opinions on BMW diesels. We had a D-35 in our previous boat and were pretty happy with it. Only issues were due to its being raw water cooled and consequent salting up of the coolant passages. Had well over 6000 hours on it when we sold the boat and was still running well. It was a shaft drive and all the running gear was solid. The Hatz industrial engines that they were based upon had a good rep too... lots used in reefer containers and they would run forever with little maintenance (by reputation, not by my experience).

Jim

I am also surprised at the negative opinions of the BMW diesels. We had a BMW D-50 fresh water cooled. It was 35 years old with high hours, never rebuilt and still running like a new engine when we replaced it. It would fire up instantly and run very smoothly and quietly. It never leaked a drop of oil. I was told by a mechanic that the D-50 was ahead of its time in the 1980’s because of its balance shaft which made it run as smooth as an engine with more cylinders (the D-50 was a 3 cylinder). We replaced one of its 3 injectors which were off-the-shelf Bosch injectors. The only reason we replaced the engine was due to parts availability. A company in Canada was the only place to get parts, some new and some re-manufactured. The company was very responsive and would ship anywhere but I worried about the inventory eventually drying up. The BMW D-50 was actually highly sought after by those familiar with its high quality. The Canadian parts company actually had a buyer for my engine in Europe and brokered a deal. The buyer purchased my D-50 and had it crated and shipped from Florida to Europe, all arranged by the Canadian company. I didn’t have to lift a finger. I got a report later that the purchaser was very happy with the engine.

[BlueH2Obound]

Back to the original title of the thread: "What's the worst marine diesel?"

I suspect the answer is ANY marine diesel that has suffered from poor or lack of routine maintenance might indeed qualify as a poor marine diesel engine!

Even Volvo engines (and personally, I am NOT a fan) have functioned reliably for many many owners when properly maintained and operated.