don't do the bon ami old wives tale,
would you put sand in an engine....
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don't do the bon ami old wives tale,
would you put sand in an engine....
While I would not use it, bon ami is not as bad as sand - the abrasive ingredient in it, calcite, is softer than either the bore or rings, although it is about the same hardness as the pistons, and probably the bearings.Quote:
Originally Posted by harry
Sand (silica), on the other hand, is harder than virtually any metal used in the engine (some case hardened surfaces may be as hard, but I can't think of any that would be).
The whole idea of the bon ami bit is that it will remove a glaze of burnt oil from the bores. I have no idea how effective it is, and would not do it to my engine except as a desperate attempt to delay an immediate overhaul.
John
Lots of tales on the internet of the bon ami solution (for & against).
Would switching to a running in oil (no friction modifiers) and using that for a while have a similar effect ?
Also, could the problem just be piston rings that are stuck in the grooves ?
Colin
Using Bon-Ami has been used effectively on old cast iron bores of diesel engines that had gone smokey due to glazing, but I have only heard of this being done successfully with large old truck engines in which it would have been a major effort to remove them out of their chassis for their rebuild.
Glazed bores with high oil usage, in diesel farm tractor engine's is caused by long periods of idling while cold and one cause of this is, the tractor has been used for light work such as feeding out during the winter months. The engine would come right after a couple of weeks heavy work ploughing.
I don't know if petrol engine could have the same issue of a glazed bore and like the others have said, I would be starting with fitting some new valve stem seals before committing to a engine rebuild.
.
Went down to Supercheap to look at compression gauges and the cheapest on offer was $60.
A VRS gasket set is about $90 delivered. I might just as well whip the head off, do the seals and have a look about while I'm in there.
Its a kind of back burner project as the wife wants the house jobs done first. What a strange woman she is ;)