One more horrible example: D2 oil screen as removed from engine. Under that black is a layer of blue silicon gasket maker. It was everywhere in the engine and the screens were about 20% open at best.

For heavens sake, take it easy with that stuff!

Jack;)

Jack - Good pic and 'heads-up' of the potential damage that careless use of silicone gasket maker can do. Not the first time I've heard of an engine rebuild that failed after a short time, due to silicone clogging oil pump suction screens.
The stuff is good .. if used sparingly, and the surfaces are clean .. but it's too easy to lather it on .. and you can't see the amount squirting out on the underside, as you tighten things down ..

Yes, no matter what color, too much silicon will do an engine in.
About 10-12 yr ago a shop overhauled my 7.3 truck engine. I had a bad feeling about the overhaul & performance, but 14-18hr days & I didn't have time to follow up.
About 1 yr later I pulled it back down, and literally pulled, scrapped, & dipped over 2 big handfulls of red silicon out of the pan & off the oil pick-up screen. Got another handful out of rest of the engine.
Upper end was toast.
There was other issues with the overhaul, but mostly the silicon did it.

Ya know, tuition to the "School of Hard Knocks" is costly, & I keep learning the hard, spendy way....

You sure can track a mechanic that uses the stuff. You know what he disassembled and reassembled. Of course a whole overhaul with it would muddy the water for the repairs following unless they were a different color.

In my youth I messed about with Triumph motorbikes and at the start I used silicon-no more. I quickly learnt that new gaskets applied properly to clean gasket surfaces will never leak even on old Triumphs!!!! If you still cannot get the leak stopped check for distortion.

Neil

I never had any love for it but if I thought a little more sealing was needed & at the Cat dealer shop we always used #2 Permatex for a sealer on gaskets & never ever saw any buildup anywhere in an engine if you didn,t over due it.Where I never put a head on without coating the gasket was the D4s up through the 7U series & esp. the D6s up through the 9Us which were the worst for outside weeping. The Permatex would stop this problem & we never put a head on them without putting a sparing coat on them. Through experience you learn where it,s needed & not needed.

I use the pressurized cans, much better control of how much you want to use, used sparingly as OzD said you can't even tell there was silicone used.
I have seen radiators plugged from the it, carbs plugged, hydraulics etc. and stuff like Jack's example.
Just the visual of slicone all over scares me if i am looking at a piece of equipment to buy.
Seen a Massey Fergusen just testerday with silicone on the exhaust manifold and everywhere else you could think of:eek:
Never looked, but they might want to put warning signs on the silicone tubes, there are warnings for every other thing you can think of today.
Do the women in Hollyweird use to much silicone too:D

Don't get me wrong, the stuff is great used carefully. I nearly always use it just as I used to use the old Aviation Grade Permatex--just the thinnest skin of it on a proper gasket. I prefer GASKET CINCH but it is hard to find and VERY expensive.

This engine had "cobwebs" and globs everywhere. It had a big chunk lodged under the oil relief valve ball! It was in the crankshaft bearings, in the rocker cover, the filter housing, oil manifold--just everywhere.

Be kind to your relic. Use carefully.

jack