Volvo Penta MD1a

Jase6100

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I have a Kings Cruiser 29 that is powered by a Volvo Penta MD1 engine. I have had the boat for a year with most of that time being on the hard. I have changed some gaskets and thermostat and when starts it runs really well. I have problem with shutting off the engine.

I was told by the previous owner to lift the decompression lever to cut the engine but after researching online and talking to people this does not seem to be the preferred method. It has been suggested that there is a manual cut off but struggling to locate.

I would be grateful if anyone has any experience of these engines who could advise.

Thanks

Jason
 
I have a Kings Cruiser 29 that is powered by a Volvo Penta MD1 engine. I have had the boat for a year with most of that time being on the hard. I have changed some gaskets and thermostat and when starts it runs really well. I have problem with shutting off the engine.

I was told by the previous owner to lift the decompression lever to cut the engine but after researching online and talking to people this does not seem to be the preferred method. It has been suggested that there is a manual cut off but struggling to locate.

I would be grateful if anyone has any experience of these engines who could advise.

Thanks

Jason
I agree that releasing compression is not the best way to stop a diesel engine. As Vic says, shutting off the fuel in one way or another is to be preferred.

Richard
 
I had an MD2 for decades. As Vic says, you close the throttle and it stops. The throttle should close all the way. Take a look at the linkage.
This may only be true if a two lever control. A single lever control brings the engine to idle and then need to pull the stop handle which brings the engine governor speed lever to the stop position .
 
Thanks very much for the replies. It is a MD1A and I found this when I got a new thermostat When the throttle is pulled back to the upright position it continues to idle. Pulling it further back causes the revs to increase.

I have looked where the throttle cable attaches to the engine and tried to manipulate the lever but it won’t shut down from there.

I’ll have another look at the weekend and take some phots. If it’s possible I’ll upload them on here as they will give more accurate view rather than my description.
Thanks

Jason
 
Jason.. Is it a two lever control....IE one lever throttle and one lever gears or is it a single lever doing throttle and gears . The single lever would do what you are saying as it has idle at mid stroke and then speeds up when pushed in either direction to give forard one way and astern the other. I think most MD1a were supplied as two lever so maybe yours has been modified. If hat has been modified from two lever to a single lever then you will need a spring compression link where the speed teleflex joins the governor speed lever so that the speed lever can be pushed to below idle speed. Not sure if these parts are available from a parts supplier but someone who has junked an MD1/2/3 A might pass one on.
 
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Thanks very much for the replies. It is a MD1A and I found this when I got a new thermostat When the throttle is pulled back to the upright position it continues to idle. Pulling it further back causes the revs to increase.
I have looked where the throttle cable attaches to the engine and tried to manipulate the lever but it won’t shut down from there.
I’ll have another look at the weekend and take some phots. If it’s possible I’ll upload them on here as they will give more accurate view rather than my description.
Thanks

Jason
As a new member you will probably not be able to upload photos ......... It's a privilege you earn after making many posts .... ( about 5, I think)
( you may also have to reduce them to an acceptable size )
 
The MDIA wasn’t around for long iirc.
Well, as the MD1 it's been around since 1958, MD1B were made between 1970 and 1973.

I have one, sadly not running at present but a "project" I'd like to get back up and running. It came with two levels and I'm pretty sure they were original.

I'd love for this to be resolved because it's a pain in the ass findin parts for them. All the traders selling "MD1" parts generally ended up being MD1B parts.

At present my money is on the MD1 being the MD1A, renamed when the MD1B came out (see below) but if someone has a list of engine numbers that says otherwise, I'd be interested in seeing it.

If it's of any help to the Original Poster, I have an original parts manual for one that I'd be happy to copy for costs or trade. They don't appear on the Volvo site etc as a fiche. I found many dealers aren't even able to access one. Sometimes you can find parts via the numbers, or that the numbers have been superceded by others and, hence, still available for other models.

Useful for re-assembly too.

Screen Shot 2020-07-24 at 00.54.31.png
 
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Hello,
It has one lever. To start the engine the stick is pulled out and pushed down for full revs. To engage forward or astern the head of the lever is pulled up and pushed down into the desired position. Had the engine running again this weekend and took the boat around to step the mast. However on return to the pontoon found that it would engage astern. Another issue to get sorted!
 
Hello,
It has one lever. To start the engine the stick is pulled out and pushed down for full revs. To engage forward or astern the head of the lever is pulled up and pushed down into the desired position. Had the engine running again this weekend and took the boat around to step the mast. However on return to the pontoon found that it would engage astern. Another issue to get sorted!
The gearbox originally used (RB) was not controllable by a single lever control which was designed to use 3” nominal stroke cables which could not cope with the leadings
the MD1B had a choice of the MS or RB boxes

MD1 did not have oil filter but exhaust manifold was integrated in cyl head and had a shorter injector
not sure it had a thermostat?
the number and location of the head studs is actually the best way to check but I can’t remember what they were
 
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Right. Single lever. Ignore my earlier post and look for the stop mechanism!



When these engines are single lever operated then there is a spring compression link between the governor speed lever and the teleflex throttle cable and there is also a drilled brass bush on the governor speed lever through which a stop wire is fed with enough of a tail to allow the throttle to operate and a clamp bush fitted which is operated by a stop handle that maybe be in a cockpit locker or the cabin. The stop wire pulls the speed lever against the spring connection to the throttle which allows the fuel to be shut off. Maybe some one can provide a piccy. You should be able to stop the engine by reaching down the starboard side from the cabin and pulling the speed lever forward which is what I do when it is raining :)
 
Thanks again for the replies. I have arranged for someone to come and have a look in a couple of weeks. I will share your information Bilgediver. The engine needs all the fuel removing, the tank cleaning and new filter. In addition, to sorting out the stop function and engaging the astern gear. No way will I attempt to venture out into the Humber estuary without a fully functioning engine.

I have spoken to quite a few people and those who have seen the engine running have said although it’s old it runs really well and should be good for years. However, I continue to contemplate a more up to date replacement.
 
Quick update on the MD1. The cylinder head has been removed to re seat the valves. The injectors have been checked and atomise effectively. The fuel tank has been steam cleaned. The control arm that shifts gears is been slightly modified as the morse cable was not tensioned enough to fully engage astern. The problem with the stop function remains but will explore the spring connection solution. The consensus is to get the engine operating as it has life left, rather than getting a replacement

Thanks for all the input.
 
There should be a spring link connection set up so that when the stop wire is pulled the spring compresses allowing the governor arm to move to the stop position. . I thought I might have the bits here in a donation of bits from another sailor but no luck. is there a brass nipple on the governor arm drilled horizontally about 1.5 mm through which a stop wire would pass. If not I wonder if it is the older MD1 that you have which was originally designed for two lever control and the throttle would then be adjusted so that it could move all the way to stop position and idle speed set by adjusting the speed lever .
 
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