Hot Rods 65 MEL 430 intake leak

hi all,

My brother and I are getting his Lincoln up and running again and when we fired it up today there was a steady small stream of coolant collectingunderneath the intake manifold and dripping off the back of the engine block.

Checked all hoses and no leaks anywhere that we could see.

Pulled the intake and found the front 2 coolant passages blocked off with the gasket (see pics). Is that normal?

Can you guys see any obvious signs of leaking that we are missing?

Any place else that leaks coolant underneath the intake?

Thanks!

Russell

 

Go buy a new intake gasket set and see if they are blocked off in the new set.

 

Clean up the intake and look for cracks... heavy little bugger... use a sealer on the bolts that pass through the water jacket.

 

The new gasket we got this morning also has them blocked off, so it must be normal.

There was no leaking from any of the bolts, as they are all visible. The only place that made any sense was from the lower side of one of the cooling ports, but I’m not terribly sure how the water flows through the intake

 

Quite possible none go into the head water jacket. Sometimes you can see coolant in the hole or the bolts have some sludge on them.

 

All the bolts were clean with no sludge

 

The front coolant ports need to be blocked off. That forces the coolant to circulate to the back of the motor properly. They are only there because Ford could use the same tooling for left and right cylinder heads if the ports were symmetrical. Letting the gasket do the work is much cheaper then having separate left and right tooling.

 

Well,

We got the intake off and cleaned up. Quasi pressure tested the manifold off the car and didn’t see any leaks on the manifold itself. Cleaned up the mating surfaces on the manifold and heads. There was some pitting on the rear water ports of both the head and the intake.

Also found that the previous owner overcame a massive deformation on the coolant expansion tank by using a crap ton of gasket maker so that’s a problem.

Put it all back together with felpro gaskets and tightened the manifold bolts first to 12 ft lbs, then 18, then 26. Hooked a hose up to the radiator inlet and just started putting water in and got a slow leak on the driver rear water port..... this was with only hand tight pressure on the system.

Not sure what to do now.

 

Wouldn't you block off the back water ports.If the front ports are blocked off how does coolant get to the thermostat?

 

Nope. The front ports are blocked off so that you don’t short circuit the cooling around the front of the engine. It forces the water through the back of the engine. At least that’s what I’ve come to learn

 

Never worked on a MEL how does coolant get to the thermostat?

 

My guess is that the stat is located between the surge tank and the intake manifold like a 352 or 390 Ford.

 

My question does the coolant flow in a passage under the carbs to the front. https://www.ebay.com/itm/Mercury-Super-Marauder-3x2-Intake-Stock-Tripower-Manifold-430-/191876550550?nma=true&si=KYV%2BtIGOWba5nr5QE7oIXYZqczE%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

 

Yes, The Intake manifold has a coolant passage that leads from the rear of the heads, forward to the thermostat mount that is in the front of the intake. It also serves to warm up the floor of what is a rather large cast iron "Air Gap" style manifold.

From the web:

 

Just read this, I can't believe you didn't see the three Welsh / freeze plugs on the underside of the manifold...this is where they leak as well as the rusted out bypass pipe.

 

these engines also run three thermostats...crazy eh!