Disolving old hard grease?

Vegable

Member
Joined
4 Mar 2010
Messages
284
Location
me : Pwllheli Boat : Arisaig
Visit site
Having fought my way to the inside of my extreemly stiff hand anchor windlass, its full of old hard chunks of grease that's more like treacle toffee than grease. Parafin doesn't seem to do much. What's best to soften it and if at all possible flush the old grease away? It's removed from the boat and in my garage.
Mike
 

prv

Well-known member
Joined
29 Nov 2009
Messages
37,363
Location
Southampton
Visit site
Diesel (basically the same as paraffin for this purpose I think) worked ok for me, but if you need something fiercer then perhaps acetone?

Pete
 

AntarcticPilot

Well-known member
Joined
4 May 2007
Messages
10,010
Location
Cambridge, UK
www.cooperandyau.co.uk
I've used all sorts, and nothing works 100%. So far, the best success has come from my brother using a degreaser for car parts, using caustic soda solution under pressure through a nozzle. The problem isn't where you can see the hard, brown varnish like deposit; it's where it is hidden inside things like roller bearings.
 

NormanS

Well-known member
Joined
10 Nov 2008
Messages
9,398
Visit site
A hair drier would soften the old grease, then paraffin or diesel with a brush should wash it away.
 

vyv_cox

Well-known member
Joined
16 May 2001
Messages
25,351
Location
France, sailing Aegean Sea.
coxeng.co.uk
Grease is always rather difficult to remove as it is a mixture of hydrocarbon oil and water-based soap. Modern soaps themselves tend to be rather insoluble in water. A lighter hydrocarbon solvent than paraffin or diesel may be found more effective for old, solidified grease. In the lab we would use hexane or heptane, the nearest equivalent outside being gasoline. A detergent solution should then remove whatever remains.
 

Vegable

Member
Joined
4 Mar 2010
Messages
284
Location
me : Pwllheli Boat : Arisaig
Visit site
Grease is always rather difficult to remove as it is a mixture of hydrocarbon oil and water-based soap. Modern soaps themselves tend to be rather insoluble in water. A lighter hydrocarbon solvent than paraffin or diesel may be found more effective for old, solidified grease. In the lab we would use hexane or heptane, the nearest equivalent outside being gasoline. A detergent solution should then remove whatever remains.

Thanks for your replies.
If grease contains soap, then will boiling the whole unit in a strong sugar soap solution in the wifes biggest pan work?
Mike
 

VicS

Well-known member
Joined
13 Jul 2002
Messages
48,144
Visit site
I reckon scrape and wipe away as much as possible , then wash of what will wash off with paraffin. Finally once you have removed them clean up the bearings themselves with gasoline but remembering its highly flammable nature.

Unless of course you happen to have a private stockpile of 1:1:1-TCE.
 

lpdsn

New member
Joined
3 Apr 2009
Messages
5,467
Visit site
Having fought my way to the inside of my extreemly stiff hand anchor windlass, its full of old hard chunks of grease that's more like treacle toffee than grease. Parafin doesn't seem to do much. What's best to soften it and if at all possible flush the old grease away? It's removed from the boat and in my garage.
Mike

A common trick with winches that are clogged up with hard grease is to liberally soak it in 3-in-1 oil or WD40, re-assemble them and use them for a short while, then disassemble again and clean as usual.
 

30boat

N/A
Joined
26 Oct 2001
Messages
8,558
Location
Portugal
Visit site
A common trick with winches that are clogged up with hard grease is to liberally soak it in 3-in-1 oil or WD40, re-assemble them and use them for a short while, then disassemble again and clean as usual.
That's what I always do.WD40 makes short work of old grease.
I wouldn't use caustic soda anywhere near aluminium!!
 

Daydream believer

Well-known member
Joined
6 Oct 2012
Messages
19,055
Location
Southminster, essex
Visit site
Ha ha ha!

Yes! you might laugh, but as an experiment put some new grease on a tin lid. Hold it in some pliers & heat the tin with a blow lamp. I did & got the tin lid red hot & the grease did not have any visible change.
Old grease that has hardened will have done so due to some chemical reaction or addition of something ( dirt etc). Dissolving it in another chemical or boiling it in something is altering the structure of the grease so does not mean that the grease itself is being changed by heat only
Of course there are different types of grease ,& I am not suggesting you do this with your K Jelly etc. , but the usual high speed bearing engine grease does not always react as you might think. Many are specifically designed to be unaffected by a limited amount of heat
 
Last edited:

aquaplane

Active member
Joined
16 Sep 2006
Messages
2,679
Location
West Yorkshire
www.utilitywarehouse.co.uk
If the grease is fat, animal fat, caustic would work as it turns the fat into soap, but I don't think we are asking about fat.

From personal experience cleaning up a car engine, acetone won't be effective on grease/oils either, it's too polar a solvent. Acetone is a very good solvent in some cases but this isn't one of them.

I would go for paraffin/diesel/petrol cold first but warm if possible. I can't see how you would safely warm petrol though. Paraffin and diesel have similar flashpoints at ~80°C but petrol will ignite at less than ambient so it's much more dangerous.
 
Top