Topic: 390 Water pump gaskets, thermostat housing gasket

[preaction]

These three gaskets are just paper cutouts of the shape needed, does anyone have preparation that  is done to these gaskets to ensure they don't leak? I just finished disassembling my leaking water pump and T stat housing gaskets from leaks from both just from filling the cooling system and I don't want to have to do that again. The first attempt I installed them dry and as delivered and for some reason they all leaked. All of the surfaces were cleaned well and decreased with acetone. Thanks for any ideas, Paul.

[Bob Gaines]

These three gaskets are just paper cutouts of the shape needed, does anyone have preparation that  is done to these gaskets to ensure they don't leak? I just finished disassembling my leaking water pump and T stat housing gaskets from leaks from both just from filling the cooling system and I don't want to have to do that again. The first attempt I installed them dry and as delivered and for some reason they all leaked. All of the surfaces were cleaned well and decreased with acetone. Thanks for any ideas, Paul.

I typically glue the paper gasket to the intake or in the case of WP to the block and use silicone gasket sealer (what ever brand is your preference ) to the thermostat housing or waterpump . That way if you need to change it for some reason in the future you can typically break it loose from the silicone without destroying the gasket . Of course you trim the silicone that squeezes out before painting for the assemblyline look. A thin skim coat of silicone and it will seal up again.At least that is what I have done forever and seems to work. Others may have different way.

[preaction]

Thanks Bob, that's what I have come up with and will try.

[J_Speegle]

I've used Form a Gasket on both sides after I've checked the condition of both surfaces and corrected that issue if present. Like Bob I then would clean off any excess and if the gasket will be seen in the final product remove any excess and dress the edges of the gasket with a nail file if needed

[jwc66k]

I've used Form a Gasket on both sides after I've checked the condition of both surfaces and corrected that issue if present.

I don't know if it was Permatex Aviation Form-A-Gasket back then (it's what is in my beer fridge), but it was what my father used way back, when he taught me how to rebuild engines. He was a Chief Aviation Machinist Mate in the US Navy.
Jim
 

[preaction]

Thanks for the replies for if anything I needed some moral support. Don't get me wrong I love wrenching on my car and the more detailed the better but I found these coolant leaks after a motor repaint and much detailing from what I have learned from the great people from this site. After reassembly and installation into the car as I filled the radiator and in my mind I was about 2 minutes from turning the key for a test ride, I had water leaking from the water pump gaskets, I later found only two of the 4 pump bolts fully tight, and water leaking from the radiator cooling line fitting on the radiator I think from a over zealous tightening of the connection. I hope to be finished this weekend.

[lancelot66]

I have hesitated to jump in on this thread for the primary reasoning that I just didn't quite feel qualified because I've never cracked open a 390 and worked on one. I've been behind he wheel of a couple in the family over the years, changed a fuel pump on the side of I5, near Redding, CA in the summer on my Dad's '72 F250 Camper Special, but never inside of one.
The rest of this subject I've been doing the exact same thing recently, had 3 failures before what I believe to be success (so far at least) with my A Code 289, all the factory accessories present, minus one: have Thermactor, A/C and Power Steering brackets present, all having to bolt up to the water pump, and then I added an NOS Idler pulley on the A/C belt to get rid of the belt vibration I always managed to get (the books call it a "slap", but my person opinion is that term doesn't quite accurately describe it). Anyway, and something I'll NEVER ATTEMPT ever again, is to do all this tear down of the engine to detail it with new paint, replacing every single gasket that could leak with cork, paper, etc., except for the intake, restoring the original factory Thermactor Equipment and putting it back on the engine finally (been probably 15 years at least since I removed it), detailing power steering pump, installing Fred Ballard's restored, date code correct Carter fuel pump, installing a C6OE-A water pump finally....and doing this without pulling the damn motor. NEVER AGAIN!  The air log tubes for the thermactor were headache enough. This car is early enough to have the lock straps on the exhaust manifold bolts, to ensure good knuckle contact when your in there tightening it all up, Autolite plugs, Kevin Marti's plug wires, etc, etc.

But back to the water pump...I have a backing plate on mine, not sure of the configuration on a 390, so there are 2 paper gaskets involved. I tried Hylomar Blue gasket sealer on it the first time, screwed it up by missing a couple of gasket holes with bolts that were angled incorrectly, leaked all over my garage floor. Took it apart again (all the brackets, fan blade, clutch fan. shroud - everything) did it again with Hylomar, leaked again after all back together (3 bolts were not tight enough, as in your case - I was too afraid of over tightening past torque specs), then finally, used 2 new paper gaskets (others were ruined) and used the gray Permatex Water Pump and Themostat housing sealer they have out there now, small tubes (bought 4) but very inexpensive. And then, just like you had experienced, thought I'd replace my twisted and bent up Trans cooling lines with new ones and had leaks there too, 3 separate times (could be/should a different thread altogether from this one). So anyway, that's my experiences thus far but I "think" I'm happy with the results so far, like having everything back to stock/original, but I sure do feel your pain (still). Feel also like I could do it in the dark dead of night now too!

[RoyceP]

This is what Ford did on the assembly line, except for the part about removing excess and dressing the edges.

I've used Form a Gasket on both sides after I've checked the condition of both surfaces and corrected that issue if present. Like Bob I then would clean off any excess and if the gasket will be seen in the final product remove any excess and dress the edges of the gasket with a nail file if needed

[Brian Conway]

A little ATV or Permatex is just fine.  Don't forget the Water Pump Bolt closest to the alternator goes into a water jacket.  That bolt requires ATV or Permatex or it's a guaranteed leak.  Brian