Hi RancheroJim,

I’m fairly certain that the leak was caused by the badly eroded Water jacket passage. There should not be any area for the water to leak above the timing chain as the bolts there go straight into the block valley. The rusted area is just from where the channel directed the water up. However I did have a stripped out bolt just below the left hand water passage, but that had enough sealant to stop the leak. I have tapped it out and have a larger diameter bolt to install. With that fixed, I now should have more clamping force when tightening the timing cover, which will help.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Dennis, mine looked similar to yours but not quite as bad. It looks like your water is coming from the area above the timing chain, mine was too. I had used permatex sealant, this time I used Copperkote, sprayed the gasket a few times and let it tack up and so far after 1,000 miles I have no leaks..

No old time y-blocker here...but...I retorqued my timing cover bolts a couple of times after allowing the sealant to set up some .  Each time the bolts turned slightly more to torque.  Mine may leak too, we'll see.

Ok, round 3 for all you playing at home, haha, it’s been a while but these things can’t be rushed😅.

So I have finally had the time (and mustered up the motivation) to pull the damper and timing cover off and address this water leak for the final time (hopefully)🤞.

I preped the surface again and applied some JB weld to create more surface area on the Water jacket openings where it had been badly eroded.

I sanded and filed the surface down flush and did the same to the timing cover. Just waiting for the timing cover and oil pan gasket to arrive to reassemble.

Although it’s not perfect, I think now there is a whole lot more surface area for the gasket to mate against.







Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

 do it your way, i will doit my way,i have no leakes in this aria,tho i only did 3 yblocks last year.re useing grade 5 or worce hardware and expecting no leaks is like the lottery.as well grease hopeing to stop a leak in a eroded block makes no sense

Hi, I never use RTV with a gasket (maybe in the corners), Use RTV in place of a gasket, gasket sealer is to be used with a gasket, RTV will create worms that will end up in the oil pump pickup, Skim the timing cover and block with JB Weld let dry and stone flat (oil stone), then glue the gasket to the cover with sealer, and white grease on the block side, do not over torque.

by filling the drain trough with sealer,now the leak will go into the eng oil.the picture shows a badly eroded water port, problem not using any freeze.. not a lot of seal aria left on the block.. i would get the front cover surfaced,then glue the gasket to the cover. sealer around the port,leave the trough with (no)  sealer on the portion that sealed the oil.then make sure the right length bolted.use new grade 8 bolts and over tighten ,should do the trick. also run anyfreeze to stop the erosion. dont see the erosion her as the climate ,makes antyfreeze a must ,which eliminates erosion.

Good news and bad news... Still leaks, but just a couple of drops when cold and once it warmed up nothing. I was hoping the gasket absorbed the water and swelled up to seal. Anyway more importantly I was able to finish the run-in period, and change the oil and filter, so I'm partly happy.

Although it sounds similar to rancherojim's problem, annoying as hell but at this stage I can live with that.

I'm taking a break now so I'll let the engine cool down and check again for leaks.

Ted- thanks for the feedback. I was sure to seal up the threads and check bolt length. Although In hindsight, I should have applied a skim of RTV around the water passages.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Looking at your picture it almost looks like the leak is coming from above the water passage unless the pressure is forcing it upward into the top groove?  There is nothing to leak up there unless it is on the timing cover in the water pump area?
I'm dealing with the same problem but not so severe and just one side. Mine doesn't leak when hot and running, it starts after the engine cools and sits over night then I lose about a teaspoon. It's just aggravating as hell after doing my rebuild and being very careful to do everything right. I've rebuilt a few Y's over the years and this is the first one with the problem.

Good luck I hope you solve it.

As suggested above by both Charlie and James, be sure to put some sealer on the threads of the two bolts that go into the block holes located just below the two main coolant passages in the block.  Those two threaded holes are open to the interior of the block and are not ‘blind’ holes.  As such, coolant can leak past the threads to the outside of the block.  Also insure that the bolts are not too long as they can contact the cylinder wall and in doing so will create other problems.

Lorena, Texas (South of Waco)