Blocked engine block drain, Volvo 2003

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pmcdermott

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Any suggestions for sorting out a blockage in the drain port on the starboard side of a sea-water cooled Volvo Penta 2003.

So far I have tried:
1. Removing both the drain cock and the 2nd piece it screws into
2. Have a good poke around with a round file, a small drift and a narrow pointed tool
3. Flushing the engine with Rydlyme via the thermostat housing (RK Marine suggestion)
4. Using small nylon bottle brushes
5. Pumping some warm water with washing up liquid into the outlet with a small pump to flush it

If I poke around I can easily extract a small amount of very black dirt each time and wipe it on a rag. I must have spent an hour doing this on Sunday, but still no sudden gush of water from the engine block I was expecting and familiar with.

I would like to get this solved as I worry it is symptomatic of cooling water not circulating round the block generally. I also can't drain the engine properly if I want to.
 
That is assuming the water is getting through. The fact that you are extruding dark grey gunge does suggests it is.
Use a drill bit turned by hand, it does take time but it does work.
When you succeed leave the drain plug out, remove the thermostat, and pour fresh water down thermostat housing. If water comes pouring out you know the slotted tube that lets water down from the cylinder head is clear too.
 
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Still struggling with this. Tried a piece of coat hanger wire per RichardS's suggestion but no luck. It meets very firm resistance. Should I try bashing the end of the wire with a hammer to break through?

The cylinder head is now off (the reason I was trying to drain the engine in the first place). Which hole is the way in from the top of the cylinder block?
 
Did this on my 2002, as I recall it the passage angles away (aft?) pretty sharply, so bashing the wire is probably not a good idea.
I'd try bending the first 2-3cm of wire a bit and poking around with it to identify which way the passage goes off to, and then try to push the wire in that direction.
On mine I used a very large zip-tie as that was easier to get to bend.
The crud that was in my cooling passages was not solid, more like rust flakes and sand but I suppose yours could have scale in them which may be much more solid.
 
When you do finally get it flowing, Hydrochloric Acid is your weapon of choice for cleaning it out. It dissolves limescale, marine creatures and rust with equal ease.

Topping it up and leaving it to soak for 24 hours in Hydrochloric should dissolve all the crud. You can get it on eBay, or if you prefer it is sold as brick cleaner for mortar at builders merchants, or sometimes as rust remover or patio cleaner at twice the price.

If you really feel particularly rich, I believe there are "marine" versions of hydrocholric sold at even greater expense such as RydLyme (which is listed in it's MSDS as 5-9% Hydrocholic) ... but basically, it is just Hydrochloric, with yacht tax added.

https://www.ebay.co.uk/itm/Hydrochl...077326?hash=item1ea6b7b98e:g:nf8AAOSw4GVYIzpr
 
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pvb said:
The OP said he'd already tried that.
Click to expand...

But he did not have any flow and he was using Rydlyme which really needs to be circulated hot.

If he just poured rydlyme into the thermostat housing without completely draining the block it would have got nowhere near the blockage he is trying to clear
 
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How far in is the piece of wire going in? you should be able to get in in about 5/6 inches,maybe a bit more.
As I said in an earlier post wire did not do mine, not rigid enough. If you can't get a long thin screwdriver in use the longest and fattest drill bit and turn it by hand. when you have exhausted its length then try something stiffer than wire to break through the last inch of crud.
If you have cleared the drain hole, and nothing comes out, then the tube with holes in, that lets water down from the cylinder head is blocked. http://www.marinepartseurope.com/en/volvo-penta-explodedview-7726000-21-11524.aspx

Part no 6 I believe.

Just to add, what you poke up does not need to be flexible. It is a straight run from the plug hole to the water jacket.
 
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ottow said:
Did this on my 2002, as I recall it the passage angles away (aft?) pretty sharply, so bashing the wire is probably not a good idea.
I'd try bending the first 2-3cm of wire a bit and poking around with it to identify which way the passage goes off to, and then try to push the wire in that direction.
On mine I used a very large zip-tie as that was easier to get to bend.
Click to expand...
Thanks for the tip that the passage angles aft. On my Moody 31 access to the drain cock is from the rear of the engine, so I suspect I would naturally poke forwards rather than backwards as the angle gets quite awkward.
 
VicS said:
But he did not have any flow and he was using Rydlyme which really needs to be circulated hot.

If he just poured rydlyme into the thermostat housing without completely draining the block it would have got nowhere near the blockage he is trying to clear
Click to expand...

Yes, I have already tried Rydlyme. But I agree there was no flow, especially through the cylinder block drain. I did not circulate it because I could not figure out a good way of collecting the water from the triple(?) right angle tube that goes from the head into the exhaust elbow. Plus RK Marine suggested just pouring it in the top through the thermostat port.
 
rszemeti said:
When you do finally get it flowing, Hydrochloric Acid is your weapon of choice for cleaning it out. It dissolves limescale, marine creatures and rust with equal ease.

Topping it up and leaving it to soak for 24 hours in Hydrochloric should dissolve all the crud. You can get it on eBay, or if you prefer it is sold as brick cleaner for mortar at builders merchants, or sometimes as rust remover or patio cleaner at twice the price.
Click to expand...

Yes, I may try this, especially as I am going to clean out the exhaust elbow while everything is apart. But even if I got the drain cock unblocked I would have thought it's a bit tricky draining the engine of acid without getting some of it in the bilge etc.
 
pmcdermott said:
Yes, I have already tried Rydlyme. But I agree there was no flow, especially through the cylinder block drain. I did not circulate it because I could not figure out a good way of collecting the water from the triple(?) right angle tube that goes from the head into the exhaust elbow. Plus RK Marine suggested just pouring it in the top through the thermostat port.
Click to expand...

The usual way is to collect ir coming out of the exhaust, Rig up a means of pumping back to the beginning or get your manservant, gardener, cook, maid, chauffeur or one of the other servants or slaves to transfer it with a couple of buckets.

Even so until you get a bit of a flow through the drain you'd be wasting your time
 
VicS said:
The usual way is to collect ir coming out of the exhaust, Rig up a means of pumping back to the beginning or get your manservant, gardener, cook, maid, chauffeur or one of the other servants or slaves to transfer it with a couple of buckets.
Click to expand...

Ah! Now I understand. I think I mentally blocked out that option, because the last time I tried it was a complete pain to get the exhaust hose both off and back on the exhaust elbow...

VicS said:
Even so until you get a bit of a flow through the drain you'd be wasting your time
Click to expand...

Agreed.
 
If the 2003 is the same as the 2002 the channel up from the drain plug is straight.
I have helped two other club members to clear out that channel successfully.
Wire unless it is very rigid will not do it.
 
I did this earlier this year, under KREW2's watchful eye. I found the quickest way and least painful way of cutting through the crud was to use a relatively small flat-blade screwdriver. It removed material far more quickly than poking about with wire or a drill bit.
 
"Sailing Britaly" has a couple of videos on cleaning up the cooling system on a VP2003. https://youtu.be/xG_jm6dqiKc

Not exactly what you are doing, but you may have to do the "flute" as well, if things are as gunged up as it sounds.

There's another one further (part 3) up his Youtube channel.

Some useful tips and thought-provoking projects, as well as cute baby antics, if you like that sort of thing.
 
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