thebruce

I completed a cam swap in my '74 L-82 about a month ago with the advice of some folks on the forum, and the Shark has been running great, until....

I was on the freeway 2 days ago, and I noticed my temp gauge starting to climb (I run a low temp thermostat, so it was very noticable). I got the car off the freeway quickly, and by this time had a ton of steam pouring out from under the hood. I gave it a once over and saw that the alternator/water pump belt had let go, which explains the overheating. I have replaced the belt already, but I noticed that the steam seemed to be venting from between the intake manifold and the block, on the front side :confused:

I managed to get the car home in one piece, and I started it in the garage after refilling the radiator. Sure enough, there is coolant pouring out of where I saw the steam leak.

I'm guessing that since the overheating engine created a bunch of pressure int the water passages, the steam just found the path of least resistance to escape, which in my case was through the gap between the intake manifold gasket and the front seal (which I thought I had sealed really well). If so, the fix should be pretty simple-- pull the manifold and replace the gasket and seals.

Before I do, anyone want to send me any "you should also check this..." advice? I'm really worried about blocked water passages, etc.

Thanks.

1979toy

Change your oil! You may have gotten water in to the lifter valley area.

MikeC

Where exactly is the leak?

Is it the head/intake manifold surface or the block intake manifold surface?
I would assume the first. because if it was the second for it to leak coolant out of there, your lifter valley and therefore whole crankcase would be full of water.

For the head intake manifold surface, replacing the intake gaskets should do the job.

But if its the second, watch closely and make sure its not the thermostat housing that is leaking, also you could have cracked the intake manifold or thermostat housing.

I hope the problem is cheap and easy to fix.

Budman68

Install Teflon sealant around all the bolt threads when reinstalling the manifold. It will prevent the breakdown of the gasket you just experienced.