Dismantling and reassembling a VP2002 heat exchanger?

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Chuckle54

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Any tips for dismantling and reassembling a heat exchanger and associated plumbing on a volvo penta 2002?
All the joints on the pipe work are covered in a grey deposit which I'm assuming are signs of weeping as are the end caps of the heat exchanger itself. I'm about to have a go at taking it all apart and cleaning everything so hopefully when it all goes back together it will work without loosing any coolant. Whats the best way to clean the joints prior to replacing the o rings? I was thinking of submerging the heat exchanger in white vinegar to clean it? Any better suggestions?
 
Chuckle54 said:
Any tips for dismantling and reassembling a heat exchanger and associated plumbing on a volvo penta 2002?
All the joints on the pipe work are covered in a grey deposit which I'm assuming are signs of weeping as are the end caps of the heat exchanger itself. I'm about to have a go at taking it all apart and cleaning everything so hopefully when it all goes back together it will work without loosing any coolant. Whats the best way to clean the joints prior to replacing the o rings? I was thinking of submerging the heat exchanger in white vinegar to clean it? Any better suggestions?
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if the HE is seriously scaled up you will probably find that vinegar is too weak an acid to be effective, at least in a reasonable time scale. It is also rather dilute. A sulfamic acid based limescale remover such as
Fernox DS3 should be more effective

https://fernox.com/wp-content/uploads/sites/3/2017/12/pds_61027_ds3_2kg_en.pdf
 
Chuckle54 said:
That looks the business. Cheers
Could that solution be used to clear the engine waterways?
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It could be. Rydlyme might be a better choice for a badly scaled engine. Either would need to be heated and circulated but a fresh water cooled engine should not need any serious cleaning if always filled with antifreeze which as been prepared with low TDS water and changed at the recommended intervals.

Rydlyme would also be suitable for the HE but Fernox DS3 should be readily available from Builders/ plumbers merchants
 
As posted several times before
Mark which way the caps go on as they direct the flow which is serpentine
Make sure you put the seals on the correct end
 
And make sure you fit new sealing rings on the pipes - get proper ones from a VP dealer (and note that they are slightly different sizes).
 
VicS said:
It could be. Rydlyme might be a better choice for a badly scaled engine. Either would need to be heated and circulated but a fresh water cooled engine should not need any serious cleaning if always filled with antifreeze which as been prepared with low TDS water and changed at the recommended intervals.

Rydlyme would also be suitable for the HE but Fernox DS3 should be readily available from Builders/ plumbers merchants
Click to expand...

Hydrochloric acid (e.g. Brick Cleaner) is what I have used to clean the waterways of my Volvo 2003. I get it from the laboratory where my wife works, but it is readily available from builders merchants and (I gather) from continental supermarkets! I use concentrated (37%) HCL diluted about 10:1 - if the acid you buy is less concentrated, amend this accordingly. The procedure is:
1) Close seacock
2) Remove engine anode. This drains the engine.
3) Replace the mount for the anode ( but not the anode itself)
4) Remove the thermostat housing and thermostat
5) Pour acid into the thermostat until the engine fills up.
6) Wait - perhaps half an hour or until any visible signs of gassing at the thermostat housing stop
7) replace thermostat
8) Open Sea cock and run the engine until it reaches working temperature and then a bit longer to ensure the acid is flushed out.
9) Finally, replace the engine anode. You'll probably see a lot of little black bits come out as the engine drains; bits that are a bit too heavy for the normal circulation to take out.

The Hydrochloric acid won't affect marine life; it lives in a solution of chloride ions and the acidity will be diluted or even neutralized..
 
AntarcticPilot said:
Hydrochloric acid (e.g. Brick Cleaner) is what I have used to clean the waterways of my Volvo 2003. I get it from the laboratory where my wife works, but it is readily available from builders merchants and (I gather) from continental supermarkets! I use concentrated (37%) HCL diluted about 10:1 - if the acid you buy is less concentrated, amend this accordingly. The procedure is:
1) Close seacock
2) Remove engine anode. This drains the engine.
3) Replace the mount for the anode ( but not the anode itself)
4) Remove the thermostat housing and thermostat
5) Pour acid into the thermostat until the engine fills up.
6) Wait - perhaps half an hour or until any visible signs of gassing at the thermostat housing stop
7) replace thermostat
8) Open Sea cock and run the engine until it reaches working temperature and then a bit longer to ensure the acid is flushed out.
9) Finally, replace the engine anode. You'll probably see a lot of little black bits come out as the engine drains; bits that are a bit too heavy for the normal circulation to take out.

The Hydrochloric acid won't affect marine life; it lives in a solution of chloride ions and the acidity will be diluted or even neutralized..
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That's very useful thankyou.
Just had a thought after posting my response. My engine is fresh water cooled with a sealed circuit. Can i still use this method?
 
Last edited:
Chuckle54 said:
That's very useful thankyou.
Just had a thought after posting my response. My engine is fresh water cooled with a sealed circuit. Can i still use this method?
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Well, you'd have to figure out a way to purge the acid (even if it's RydLyme or Fernox, not HCl) from the circuit. I guess you'd have to drain the acid solution out, and flush it through with fresh water several times before refilling with the appropriate coolant. Of course, you'd have to have a container under the drain; you probably don't want an acid solution swilling round your bilges.

I did think of one snag for 2001 and 2002 owners - the drain plug on the 2003 is in a different position, low down behind the alternator, where it drains the block quite nicely. But the drain plug on the 2001 and 2002 is higher up, and might not be effective in draining the engine.
 
Depending on the engien age I would recommend chucking the heat exchanger and replacing it with something more conventional from ASAP. Yes we did this and never looked back.

Got away from all those amazing engineering wonders like the outrageously expensive little bits of rubber that are essential and all different sizes.
Volvo engineering development must be on something very special for some of their solutions. Great when the engine is new, but once it ages a bit then things get difficult.

Then of course there is their stern gland......
 
Gwylan said:
Depending on the engien age I would recommend chucking the heat exchanger and replacing it with something more conventional from ASAP. Yes we did this and never looked back.

Got away from all those amazing engineering wonders like the outrageously expensive little bits of rubber that are essential and all different sizes.
Volvo engineering development must be on something very special for some of their solutions. Great when the engine is new, but once it ages a bit then things get difficult.

Then of course there is their stern gland......
Click to expand...

In fact, I don't see the point of freshwater cooling for these engines - they are designed for raw water cooling, and the engine block and head is so massive that the engine will die from something else before rust gets it! The added complication of freshwater cooling doesn't seem to stack up in the cost/benefit stakes.
 
Gwylan said:
Depending on the engien age I would recommend chucking the heat exchanger and replacing it with something more conventional from ASAP. Yes we did this and never looked back.

Got away from all those amazing engineering wonders like the outrageously expensive little bits of rubber that are essential and all different sizes. .
Click to expand...

You've mentioned that before. Could you provide more details?
 
scottie said:
It’s a 2002 so fresh water cooling is decided advantage
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I ask for information, not to doubt you. Why? The 2000 series are essentially the same engine with different numbers of cylinders - all the ancillary equipment is the same, and the castings are similar - it's a very modular series. So why is freshwater cooling beneficial to the 2002 when it isn't for the 2003?
 
Gwylan said:
Depending on the engien age I would recommend chucking the heat exchanger and replacing it with something more conventional from ASAP.
Click to expand...

If the OP's heat exchanger is serviceable, your suggestion would just involve a lot of unnecessary work and expense.
 
AntarcticPilot said:
I ask for information, not to doubt you. Why? The 2000 series are essentially the same engine with different numbers of cylinders - all the ancillary equipment is the same, and the castings are similar - it's a very modular series. So why is freshwater cooling beneficial to the 2002 when it isn't for the 2003?
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Only mentioning 2002 as it is the engine referred to in the post although I note that their is nothing shown for 2001 in the parts list only the multi cyl engines
 
The reason behind my intention to dismantle the heat exchanger and pipe work is to investigate a sudden loss of coolant. It has been suggested that a possible cause could be corrosion in the exchanger allowing coolant and raw water to mix and be expelled via the exhaust. (I'm aware that there are other possible causes) The engine runs perfectly otherwise. If nothing else it will be valuable experience.
My local engineering shop are confident that they can rebuild the exchanger if I do discover corrosion. Time will tell.
 
scottie said:
As posted several times before
Mark which way the caps go on as they direct the flow which is serpentine
Make sure you put the seals on the correct end
Click to expand...
I'll make sure they go back the way they came off..........assuming of course they're fitted properly in the first place
 
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