Salt corrosion?

PabloPicasso

PabloPicasso

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How have these salt deposits got here? There does not appear to be a water leak? Is the silver disk a core plug? Is this indicative of a major problem? Is it just a matter of clean up and paint? Are core plugs difficult to replace?
View attachment 52354

This is a pic of the side of a volvo 2001 just above the starter motor
 
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PabloPicasso said:
How have these salt deposits got here? There does not appear to be a water leak? Is the silver disk a core plug? Is this indicative of a major problem? Is it just a matter of clean up and paint? Are core plugs difficult to replace?
View attachment 52354

This is a pic of the side of a volvo 2001 just above the starter motor
Click to expand...

First guess is that the silver disc is a core plug and that is leaking slightly.

Check with the parts lists to confirm and if I am right replace it before the leak becomes serious.

No not difficult to replace May be a cup type or a welch plug can't tell from thr pic


Beaten by a stork!
 
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Ok it's a core plug/expansion plug leak. Is this a standard engine part or a special Volvo marine part? How do you replace it?
 
PabloPicasso said:
Ok it's a core plug/expansion plug leak. Is this a standard engine part or a special Volvo marine part? How do you replace it?
Click to expand...

Probably just a standard engine part but for the sake of €4 I buy the VP part...... then it's right and it'll fit

Whack it with ahammer to start with to loosen it . Punch something through the middle and lever it out.

clean up. Fit new one with some sealant . If its a welch plug whack with a hammer and drift to expand it into the hole.

There one in the head as well ( opposite side I think) inspect it but dont mess with it if its OK.


There are videos you can look at!

Corrosion I expect caused it to leak. .... Are you replacing the anode regularly.
 
It is known I think as a core plug. Not an expansion plug. It fills a hole where the manufacturer had to have access to bore out water channels etc.
I would suggest the white corrosion products are not necessarily from salt although a boat has a salty air environment. As siad buy a new plug and graunch the old one out. If I remember they are cup shaped pressed in concave outwards. I may be wrong but I think that pressing it in at the middle tends to reduce the diameter so allowing it to go in. Not as previously said hitting it to expand it. No sealer is used just clean the hole edges smooth.
As a kid I used to help my dad do motor mechanic jobs for other people. Replacing core plugs was not uncommon. I wonder now why we never see the problem in cars. Is it becuase we use inhibitor in the radiator? Certainly there are more allow blocks around now. good luck olewill
 
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William_H said:
It is known I think as a core plug. Not an expansion plug. It fills a hole where the manufacturer had to have access to bore out water channels etc.
I would suggest the white corrosion products are not necessarily from salt although a boat has a salty air environment. As siad buy a new plug and graunch the old one out. If I remember they are cup shaped pressed in concave outwards. I may be wrong but I think that pressing it in at the middle tends to reduce the diameter so allowing it to go in. Not as previously said hitting it to expand it. No sealer is used just clean the hole edges smooth.
As a kid I used to help my dad do motor mechanic jobs for other people. Replacing core plugs was not uncommon. I wonder now why we never see the problem in cars. Is it becuase we use inhibitor in the radiator? Certainly there are more allow blocks around now. good luck olewill
Click to expand...

Sorry I am going to have to disagree with William on several points.

Its called an "expansion plug" in the parts list, although fills a hole left by the manufacturing process. The Americans usually call them "freeze plugs"

Cup shaped ones are fitted cup-side out.
Disc types ( welch plug) are domed , fitted dome outer most. and expanded to fit tightly by tapping in the centre.

Some gasket sealant should be used.

See this link which seems to cover the matter pretty well http://www.howacarworks.com/cooling-systems/replacing-core-plugs
 
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Coming into harbour yesterday the engine overheat alarm went. Do you suppose these two things are connected? There was water coming out the exhaust at the time.
 
VicS said:
Sorry I am going to have to disagree with William on several points.

Its called an "expansion plug" in the parts list, although fills a hole left by the manufacturing process. The Americans usually call them "freeze plugs"[/url]
Click to expand...

Sorry Vic, you are wrong. They may call it an expansion plug, but they are wrong as well. Americans are also wrong calling it a freeze plug.

Such" plugs" used to pop out when water in some engines froze, Lucky they did for those engines , but not by design. Other engines with thinner block castings were less "lucky" ( the Ford crossflow for example, the block used to crack between the 2 core plugs on the "port" side)
 
PabloPicasso said:
Coming into harbour yesterday the engine overheat alarm went. Do you suppose these two things are connected? There was water coming out the exhaust at the time.
Click to expand...

That engine is well known for overheating if run too hard or if the waterways are blocked - assuming it is raw water cooled version.
 
Tranona said:
That engine is well known for overheating if run too hard or if the waterways are blocked - assuming it is raw water cooled version.
Click to expand...
I had trouble a few years back but the block was hard shelled critters in the sail drive leg Are you saying there maybe a blockage in the engine block? Could that cause the expansion plug problem?
 
PabloPicasso said:
I had trouble a few years back but the block was hard shelled critters in the sail drive leg Are you saying there maybe a blockage in the engine block? Could that cause the expansion plug problem?
Click to expand...

That expansion plug does not seem serious - they often weep a bit and best replaced, but unlikely to fail. Not necessarily a blockage as there is still water flowing but a gradual build up of deposits in the waterways. Also worth checking the thermostat as it may not be opening fully.
 
VicS said:
Sorry I am going to have to disagree with William on several points.

Its called an "expansion plug" in the parts list, although fills a hole left by the manufacturing process. The Americans usually call them "freeze plugs"

Cup shaped ones are fitted cup-side out.
Disc types ( welch plug) are domed , fitted dome outer most. and expanded to fit tightly by tapping in the centre.

Some gasket sealant should be used.

See this link which seems to cover the matter pretty well http://www.howacarworks.com/cooling-systems/replacing-core-plugs
Click to expand...

Hello Vic You are always welcome to disagree (with my memory especially). it was probably 60 years ago I helped my Dad. Then of course we have the language barrier for names. regards olewill
 
Ok. I cleaned off the salt deposits, there were some also around the engine anode bolt. Ran the engine hard in gear for 10min or so and no visible leaks from anywhere, not from the expansion plug, or anywhere else. No overheat alarm, all A1 ok.

All very peculiar.
 
Ok. End of the season. New thermostat sorted the overheating. The expansion plug has white deposits around it again and rusty streaks beneath. Odd because no water ever collected beneath the engine. Must be a weep I suppose rather then full on leak

Raw water drain plug removed but no flow. I guess it's blocked with crud. The Block was full of water when I removed thermostat and anode though.

Poking up the drain with seizing wire didn't help. Maybe a wire coat hanger will do it. I haven't got a bicycle spoke spare:)

I'll order a new expansion plug and a spare. Was there another somewhere on this engine, a Volvo 2001?

Thanks for suggestions/discussion so far. Any foreseeable issues I should look out for with this?
 
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