MD21B/Peugeot XDP4.9

Might be a 504.

Ariadne said:
Anybody know what car/van this little beauty went into?
Looking around at the 405/505 water pumps they all look vastly different to mine. Is it a specific VP part?
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You might like to look at these two websites. The first is the 504 and the second is the Vovo spec for the MD21B. The two would seem to have the same engines at 2100 cc with bore and stroke being the same. Only thing which does not agree is the HP but then Volvo always lied about their output power.

http://www.cargister.com/1970-peugeot-504-2-1-d-57-spec

http://www.volvopenta.com/volvopent...lication_search/pages/publication_search.aspx
 
Ariadne said:
Anybody know what car/van this little beauty went into?
Looking around at the 405/505 water pumps they all look vastly different to mine. Is it a specific VP part?
Click to expand...

The raw water pump will not be fitted to a car engine. Which pump is giving trouble on yours - the raw water pump or the coolant pump for the engine?
 
Jcorstorphine said:
I am sure it is the freshwater pump hence why he is looking at 504/505
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He says freshwater pump

Anybody know where I can find a rebuild kit for the fresh water (circulation) pump? I believe the part No. is 875372, but it seems this is no longer available or 90% of the bits to rebuild it!
The pump has just started to leak coolant, so engine running time is very, very short and if it can't be fixed then it seems I will need to replace my engine!!!!!!!!!!

Anybody want to comment on what might happen if went to a totally salt water cooling system on the engine? I really can't afford a new or reconditioned engine in the next 12 months.

Will it work, and how would I best go about it?

Cheers all
__________________
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But it is confusing because he is suggesting he runs it raw water cooled which would still require a circulation pump for the coolant in the engine. Rare for the circulation pump in the engine to fail.
 
Tranona said:
But it is confusing because he is suggesting he runs it raw water cooled which would still require a circulation pump for the coolant in the engine. Rare for the circulation pump in the engine to fail.
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I dont think he has thought the idea through.

A sea water cooled engine does not have a circulating pump, just the (flexible vane) sea water pump. I guess he wants to do away with the circulating pump and just use the existing seawater pump

I suppose coolant circulating pumps can fail... they fail now and then in cars! I replaced one in a Ford in about 1970 and one in a Volvo in about 1990 .
 
That's really the point I was making. Not sure just the raw water pump would circulate the water through the block and would have to figure out a way of getting seawater in and out of the sealed freshwater circuit which is normally also pressurised.
 
I assume the op means the circulation pump, on the marine engine this is different to the road version so a car part would not be of any use.

The 2.1 indendor engine was also used by Ford and LDV.
 
I've got an MD21A which is older but similar and has the indenor engine as its base. The reason I say this is i lknow another owner with same boat who has reengined with a rebuilt MD21B which dropped into the same slot and has lots of similar parts.

I also have a full workshop manual.

Having looked at the blow up on the VP site it looks like the MD21A and MD21B have the same water pump. Could you get one out of a scrap MD21A and refurb it?


http://www.volvopentashop.com/PSMot...DieselEngines/7742100/7742100_26/7742100_013B. VP dont have a pump in stock

Keypart quote same part number for both engines and have one in stock. here you go

http://www.keypart.com/volvo-penta/diesel-engine/md21b/19791981

hope this helps
 
OK, I'm pretty clear on what I want to know, but some are getting confused. The RAW water pump is very well and works a treat and I have loads of spare bits for it and its cheap and simple to work on.

The fresh water pump (circulation pump) has started leaking (about 1ltr of water an hour) and is going to need work done on it ASAP. I now have info (thanks) to get one from Keyparts and/or possibly get DB Marine to repair the old one with a new ceramic bit.

What I wanted to know is if it was possible to to loose the fresh water side and cool the whole engine with sea water. Doing away with the troublesome fresh water pump and maybe fitting a larger Jabsco belt driven pump for the raw water; I think I'd need a bigger pump & I have a 1" jabsco spare and waiting for a job!

Now as I have an Aluminum head (Not mine, the engines!) and a cast steel block I guess the dissimilar metals will react different rates to the hot salt water flowing around it. So I'm guessing the head will last about 400 hours before falling to bits due to anodic or cathodic reaction (not sure which, never was??).
 
Ariadne said:
OK,

Now as I have an Aluminum head (Not mine, the engines!) and a cast steel block I guess the dissimilar metals will react different rates to the hot salt water flowing around it. So I'm guessing the head will last about 400 hours before falling to bits due to anodic or cathodic reaction (not sure which, never was??).
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Outboards are aluminium and they last a resonable time but they are all aluminium and not a mixture of metals. If you go ahead, you might think about flushing the engine with freshwater any time you are tied up alongside (if you do that) Other thing is to stick in a lump of pure zinc as an anode.

Happy sailing, wish it was me, cold and windy and wet here
 
Ariadne said:
Not a bad idea that. There are a few places for anodes around the block.
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Hi there, your last posting has given me some food for thought so I have jotted down some comments next to the various points you raised.

You stated >>>>>>>>The fresh water pump (circulation pump) has started leaking (about 1ltr of water an hour) and is going to need work done on it ASAP. I now have info (thanks) to get one from Keyparts and/or possibly get DB Marine to repair the old one with a new ceramic bit.

Comment>>>>>>>>One thought to keep you going for a while is to remove the cap on the heat exchanger header tank so that the water jacket is not pressurised, that way you may not loose as much coolant due to there being less pressure on the seals. That would also let you top up without the scalding risk associated with opening the cap with the engine running. Just be careful if you try this as the water may get close to boiling so you need to keep and eye on the engine when it is under load.

You stated >>>>>>>What I wanted to know is if it was possible to loose the fresh water side and cool the whole engine with sea water.

Comment >>>>>>>>Don’t forget you need to cool the present exhaust manifold which is an integral part of the present heat exchanger and I am sure that is made of aluminium.

You stated >>>>>>>> Doing away with the troublesome fresh water pump and maybe fitting a larger Jabsco belt driven pump for the raw water; I think I'd need a bigger pump & I have a 1" jabsco spare and waiting for a job!

Comment>>>>>>>>>>I don’t think you will need a bigger pump, quite the reverse in fact. Water is very good at removing heat. At the moment your present seawater pump is keeping the engine cool through a pretty inefficient shell and tube heat exchanger. Direct seawater cooled engine only need a small amount of water through the block.

You stated >>>>>>>>>>Now as I have an Aluminium head (Not mine, the engines!) and a cast steel block I guess the dissimilar metals will react different rates to the hot salt water flowing around it. So I'm guessing the head will last about 400 hours before falling to bits due to anodic or cathodic reaction (not sure which, never was??)

Comment >>>>>>>>>>I presume the 400 hours is engine running hours but the corrosion is going to take place even when the engine is not running so anything you can do to reduce this will help. If you cannot flush the engine, think about draining it completely every time you turn it off.


The rest of my comments relate to the present circulation pump, thermostat and actual installation of the pipework

EXISTING CIRCULATION PUMP… I am presuming here that the plan is to remove the shaft from the present pump and block off the hole with a plug. This will alleviate the problem of obtaining a blanking plate and leave you a housing for a thermostat (see next item)

THERMOSTAT…..The present thermostat will be set to open and close around 90 (ish) which is too hot for a seawater cooled engine. From memory around 60 -70 is about as high as you want to be. The problem is I doubt if you will be able to source a stat which will fit in the present thermostat housing. It looks from the drawings that the stat housing is part of the water pump.

PIPEWORK…..If you do find a 60 degree stat as mentioned above, this will effectively stop any flow of water from leaving the engine and consequently, your exhaust will not be cooled (while the stat is closed) so you need to take a tee off the seawater feed to the engine and run that through the exhaust manifold and then into your exhaust. The outlet from the engine could be connected direct to a 15 mm skin fitting or into the exhaust

NO 60o THERMOST AVAILABLE…. If, as I mentioned above, you cannot get a 60 degree stat then you will need to install some form of seawater flow limiter to the engine block other wise it will run very cold and give a host of other problems.

SEAWATER INLET TO THE ENGINE……. This should be installed into the present fresh water return from the present heat exchanger so that the flow is into the block, through the circulation pump up to the cylinder head and then out to the sea.

The very best of luck from all of us poor sods stuck here in the UK. Keep on asking the questions and between all of the forum readers, we should be able to find you a solution.
 
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sorry wasn't suggesting you replace the engine with an MD21A but just that you might get a water pump off a scrapper as lots of others are still ripping them out and fitting new.

I wouldn't rebuild mine either for the reasons you quote
 
Jcorstorphine said:
Comment>>>>>>>>One thought to keep you going for a while is to remove the cap on the heat exchanger header tank so that the water jacket is not pressurised, that way you may not loose as much coolant due to there being less pressure on the seals.
Click to expand...

Good thought but I think that the MD21B runs non-pressurized anyway, ours certainly does.
The header tank cap is not of the pressure type with a spring seal but rather just a blue plastic cap that you can blow through (or perhaps ours is broken..).


Coastal Rides (01304 201073) did have a stock of the circulation pump impeller and seal, part no. 826871, because I bought one from them in October last year for my spares box. £14. Worth a try, but I expect they've sold the few they had..


The XDP4.90 was also marinised by Vetus as the P4-21 (in yellow) and by Lehman as the 4D61 (in blue?) but I don't know what pumps they used.
Also it appears in many Dutch boats as the 'Indenor Bootsmotor' (in red) though I don't know who marinised them. Interestingly though this does seem to use something akin to the standard Peugeot 504/Opel Blitz/Granada 2.1D/Mahindra Jeep water pump as can be seen in these clips.
http://www.youtube.com/watch?v=aRAmhbfElXM
http://www.youtube.com/watch?v=U1DDWGm11eo
http://www.youtube.com/watch?v=gqlte074LYE
Obviously it would require some major engineering to integrate this pump into the Volvo setup though.
 
md21b water pump

sp pumps uk will sell you a new pump for £400 or recondition your for about £90
you can get a repair kit but you are better with a recondition one.
 
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