Maybe somebody knows a good " sealant " for when I decide to try to seal it from inside ?
Problem with tank sealers/ slushing compounds is really most of that stuff was designed for aircraft to seal fuel in wing/spars etc.....Usually applied on fresh clean base material.
At the very least, on material that has a tight surface....It is also made to be applied by rotating the part to allow the liquid to roll around in the cavity and fill any voids.
This, of course will not be possible in your case....
You are dealing here with cast iron , porous and has had years of oil/coolant soak.....almost impossible to get clean and that means that the bond of any sealer will be reduced.
I would cast my vote against putting any type of tank sealer in that sump...because in the end the result will more than likely be a bigger mess than what you have now.....
Here in "Old Car" hell, can't tell you the number of times we have to remove tank sealer from old gas tanks...It never seems to be a lasting solution even if applied by pro's in a shop environment.
(many commercial radiator shops will "repair" gas tanks) Sealer is a solution some offer.....Perhaps i have been unlucky in my career to only ever see the failed sealer jobs.. none the less,
sealer would be the last choice i would exercise.
Find the leak and devise a mechanical repair if you must have a working sump.
Pipe plugs, cover plates (on the outside) with multi fastners and an epoxy sandwich to seal (plate keeps the epoxy in place...outside better chance of good surface prep)
or if cracked i would consider metal stitching using iron plugs...This can be liquid tight if applied properly using Loctite .
There are good (engine) block sealing products, but to get best results you need to circulate the sealer at an elevated temp, then drain and allow to air cure before any fluid is applied. Not
sure how block sealers will contend with cutting fluids....not what they are formulated for....Plus my belief is that they have a limited ability to seal large leaks.
Cheers Ross
