Volvo Penta MD1A

[Jase6100]

The Volvo Penta MD1 engine in my boat has a problem with the starter motor. The mechanic informed me that it has seized!

Is there any scope for this to be refurbished? I’m anticipating replacing will prove to be uneconomical.

I have contemplated a re engine but understand this is not as straightforward as it might seem as there are often additional modifications required to mounting bed, exhaust system and prop and shaft.

If anyone has any previous experience of working on these engines and has undertaken a removal and replacement I would welcome any advice and guidance.

Thanks

Jason

 

[scottie]

Early MD1 used Bosch’s dynastarter which is the most valuable item when scrapping tho comple unit
It should be restorable but beware of cost although there may be an alternative

 

[Stemar]

Is it a starter or a dynastart (big belts)? Mine had a dynastart.

I'm going to guess that your boat is almost as underpowered as mine was. If that's the case, the best thing you could do is put an engine in with a few more horses and a proper alternator. Yes, you'll probably need new engine beds, but building them up from timber formers and epoxy/glass cloth isn't difficult. The exhaust will probably need to be changed, but you can profit to fit a silencer. As for the shaft and prop, I replaced my MD1 with a VP2003 (I know, but it was free!), and the 25mm shaft was fine. The little egg whisk on the end did need to be replaced with something the bigger engine could feel.

Having an alternator was a revelation, as was the fact that in spite of the engine being way too big and powerful, it, plus a dedicated starter battery weighed less than the MD1

 

[Bilgediver]

The OP has headed the post MD1A. If this is correct then he might have starter.or dynostarter. The latter is belt driven
Both are easily serviced but identifying brushes could be problematic but help is here
Even the solonoids for the starters are available. In Scotland I have used Dingbro for these items but no doubt others can help. Just take the starter and let them decipher the markings. You might miss something important.

New parts for Dynostarter controls are available.

 

[Jase6100]

PLEASe see

 

[Jase6100]

THAnks very much for the information. Please see the picture above. Hopefully that will clarify the engine model and part.

 

[Robin]

Early MD1 used Bosch’s dynastarter which is the most valuable item when scrapping tho comple unit
It should be restorable but beware of cost although there may be an alternative

Indeed I had one such with a dynastart that failed, had it rebuilt whilst in Cowes on vacation back then but pretty sure they sent it to a specialist motorrebuild/rewind company in Southampton that was all some 40 years ago mind...

 

[Bilgediver]

THAnks very much for the information. Please see the picture above. Hopefully that will clarify the engine model and part.

That is a Dynostart. It not only starts the engine but also usually acts as a dynamo to charge the batteries but not as good as an alternator which gives a good charge at low revs. However your engine also has an alternator fitted which is good.
If the Dynostart is seized then you will not be able to turn the engine by hand. Is this the case?

It could be just a matter of fitting new bearings in the Dynostart and servicing the brushes and commutator. Any service engineer of car components can do this and your local Yellow pages of Google is a good place to start. Someone who services Bosch starters etc.

 

[Robin]

THAnks very much for the information. Please see the picture above. Hopefully that will clarify the engine model and part.

The picture puzzles me as it seems to show both a dynastart AND an alternator separately mounted. Maybe someone did a home add on but kept the belt driven dynastart purely as a starter? What boat is it ?

 

[Jase6100]

Just spoken with the marine engineer and he has clarified that the tensioner bolts are seized not the dynostart. This hopefully will be a easier fix than anticipated. However, it brings up the question of whether a re-engine is the best way forward.
I really appreciate the comments as I'm always learning and now understand better the functor a dynostart and how it differs from an alternator.
I'm going down to the boat in the next few days and will soak the bolts in penetration fluid to try and loosen them.

 

[Jase6100]

The picture puzzles me as it seems to show both a dynastart AND an alternator separately mounted. Maybe someone did a home add on but kept the belt driven dynastart purely as a starter? What boat is it ?

The boat is a Kings Cruiser 29 Class

 

[Robin]

The boat is a Kings Cruiser 29 Class

NICE.

 

[Bilgediver]

Just spoken with the marine engineer and he has clarified that the tensioner bolts are seized not the dynostart. This hopefully will be a easier fix than anticipated. However, it brings up the question of whether a re-engine is the best way forward.
I really appreciate the comments as I'm always learning and now understand better the functor a dynostart and how it differs from an alternator.
I'm going down to the boat in the next few days and will soak the bolts in penetration fluid to try and loosen them.

If that engine is performing satisfactorily then before going blindly into a re engine do some research. I notice your engine bay seems exceedingly narrow and suits the MD1A just check out various alternatives and see how you would cope. You want to avoid engines where you can not access filters and accessories on the rear end of each side where accessibility might be restricted or not possible.

The existing engine could be in good condition and give adequate service though might lack the power of some replacement engines. The alternator will take a proportion of power that is noticeable immediately after starting.

Your Dynostart should not be acting as a dynamo as you have an alternator charging the battery(s) .

Seized tensioning bolts are not a problem and easily be dealt with.

 

[NormanS]

When I had an MD1, it was purely hand start. None of this modern electrickery. It was a while ago ?

 

[Jase6100]

If that engine is performing satisfactorily then before going blindly into a re engine do some research. I notice your engine bay seems exceedingly narrow and suits the MD1A just check out various alternatives and see how you would cope. You want to avoid engines where you can not access filters and accessories on the rear end of each side where accessibility might be restricted or not possible.

The existing engine could be in good condition and give adequate service though might lack the power of some replacement engines. The alternator will take a proportion of power that is noticeable immediately after starting.

Your Dynostart should not be acting as a dynamo as you have an alternator charging the battery(s) .

Seized tensioning bolts are not a problem and easily be dealt with.

Thanks for this and previous advise you have offered in past threads on similar engine issues.
I appreciate the need to research any re-engine project as there are pifalls. The boat has adequate access to the aft engine and exhaust system by lifting the cockpit sole.
The engine has had work undertaken and has been working well up to the recent issue. I use the boat to sail in and around the Humber Estuary and an appropriately powered and reliable engine is essential. This feeds into the ongoing dilemma of whether to continue to respond to issues with this engine or upgrade. However, I do understand that issues will arise with any upgraded engine at some point and this comes with owning a boat.

 

[scottie]

The terminals on the top of the dynastarter are painted over and a separate solenoid fitted so electrics seem to be sorted out although if you could arrange an alternator cut switch it might aid starting and give some extra power when required

replacement is when rather than if but the modern shape of engines with middle of engine flywheel and the wider beds requireEd will bring their own problems

 

[V1701]

You have an alternator so I'd see if you can hand start it - the little lever with the black knob on top is a decompression lever and you'll quite possibly find a hand starter handle lurking about somewhere in the bottom of a locker...

 

[Stemar]

The engine has had work undertaken and has been working well up to the recent issue.

In that case, I'd fix the seized bolts so the belts have the necessary tension to start the beast and go sailing. However, that's a heavy boat for an 8HP engine to shove along, especially against wind and tide, so I'd start saving my pennies for a new one.

The comments about accessibility are well worth keeping in mind when you're choosing what to put in its place, and I'd choose to do more work on bearers and the like so you can fit an engine with good access to filters, water pump, dipstick and the like, rather than choosing one that'll drop in, but you need a couple of extra elbows in your arm to change the impellor.

 

[Topcat47]

As long as the engine is running, keep it. Dynastarts are dreadful, I know I had one on my old Bond 3-wheeler (I eventually fitted a kickstart). Some Parts are made of Rocking Horse shit but the engines themselves are very robust. I re-engined my boat with a 1GM 10 and needed new Mounts, a new shaft, new shaft seal, new Flexi Coupling and a new Prop. These cost me almost as much as the engine and gearbox.

 

[Jase6100]

Just a quick update. I solved the tensioning bolt problem and tensioned the starter. However, since the cold weather arrived the engine has failed to start. The consensus is a compression problem. The oil is black and smells of exhaust gases which suggest piston rings are shot.

The re engine option is still being considered and money is being saved in anticipation of this. However, I have had a very kind offer from a colleague at the yacht club to assist me in removing the piston and re ringing and honing the cylinder. I have ordered the parts and gaskets and I’m going to embark on this job. This will give the engine the final chance to power my boat for the medium term. To be honest I’m looking forward to the task and I’m sure will be a very good learning opportunity.

I was wondering if anyone has undertaken a job of this nature on the same or similar engine and could offer any advice and guidance on how to avoid and pitfalls in order to complete it successfully?

The parts and tools required for the job come to £100 so it’s worth a go. If we find any catastrophic damage then a re engine it is. Any information would be gratefully received.

Thanks in anticipation.