Oil stop leak additive

Has any body tried it? and how big a leak will it stop? TIA.

There will no doubt be folk who swear buy it but I won't ever use it. Mechanic explained it like this. Oil needs to be in every tiny nook and cranny of that engine, get through tiniest gaps, and stay there. Adding a thickener to stop a leak to that life giving lubricant to it might help a leak but you've now seriously knackered the oils ability to do its job, lubricate.

So never have never will. Lots of oil often.

The cheap ones don't really work at all. More expensive ones like Prestone ($35 a bottle) work to a degree but will not fix large leaks completely.

do not use such crap. your problem will come back with a loads of extra cost. the poster 2 discribes one option andother is they soften seals , and if you got paper gaskets the will desolf paper gaskets and then you have the oil pi$$ing ot everywhere , oil leaks stops fora few weeks till the seals are disolved and then you have 10 times more larger leeks , and got to replace all gaskets in the end of the whole engine

most good ones are not actually thickeners as you put it.

they use chemicals that replace the parts of rubber or butyl seals that are leached out by old oil. this esentially plumps them back up and softens them to restore performance. they also contain some other trickery that seems to work.

rislone rear main seal repair works on any oil leak in the engine regardless of gasket type. missing gaskets or cracked housing wont help much.

if we look at the technical data for this item its viscosity is around 140 cSt at 40'c and 14.9 cSt at 100'c this is fairly similar to the viscosity of 10w40 engine oil which is at the thinner end of you average everyday oils so you wouldnt expect it to thicken it much.

compare that to the old school morey or lucas oil stabilser where the 100'c viscosity is still over 110 cST

so i would have no problem using it if a replacement wasnt financially feasible.

yes correct and god explenation as to why it is correct.