1990 merc 4.3l w/alpha 1
petcocks not draining - removed and tried a wire to clean with no success.
When reaming out with wire it is hitting something hard like metal preventing the wire from sticking in more than 1/2" +/-.
You have to remove the little threaded T-handle completely. It screws right out and is about an inch long. It has a 90 degree hole in the end. You can't get a wire straight through it.
The piece that's threaded into the block has a hole in line with the threads. This hole is what gets clogged. With the T-handle out, you can run a wire or nail straight through the piece in the block to un-clog it.
A 3/16" drill bit on a cordless drill is quick & easy. Keep it straight to avoid damaging the threads in the brass adapter. It takes very little pressure to drill into the rust. The resultant water flow will carry out most of the rust residue.
You have to remove the little threaded T-handle completely. It screws right out and is about an inch long. It has a 90 degree hole in the end. You can't get a wire straight through it.
The piece that's threaded into the block has a hole in line with the threads. This hole is what gets clogged. With the T-handle out, you can run a wire or nail straight through the piece in the block to un-clog it.
I tried drilling but I hit something solid about 1 inch deep on both sides - Still only a slow slow drip. Is there a straight shot into block or some sort of metal plate that i am hitting or is that solid rust?
if the're the older petcocks its best to remove them completely as they only have a couple of small holes which go out sideways.if you drill them they will be no good.once removed you will see how they work and you may have some rusty sedement stopping water from getting into the small holes.you may find this type on the side of the block and maybe on riser too.do not be too heavy handed on the pressed steel t piece as its not hard to mess it up.
The problem is that the rust isn't just near the drain hole, it's all over the motor. The right thing to do would be to remove the heads and pressure wash down all the water jackets. Not fun but no other way to completely get the crude out.
ok I got her flowing - for those in same situation :
you need to put a 90 deg. bend on stiff wire as I could not clear going straight in.
Put the doglegged wire into hole and ream left and right to get between cooling jackets.
