1970 Pontiac Catalina

Engine Cooling problem
1970 Pontiac Catalina V8 Two Wheel Drive Automatic 54,342 miles

I have a 1970 Pontiac Catalina with 54,342 miles. Lately I've developed a coolant leak at the top of the timing cover between the block and cover. I'm wondering if this is and easy fix by just tightening the bolts, or will I need to replace the gasket behind there? If the gasket has to be replaced whats the procedure? I've never worked on a Pontiac 400 before, but have on other engines. Also, is there any risk of a bolt snapping off in the block? Thanks
November 28, 2009.

Actually, the timing chain cover isn't the problem, but rather that is where the water pump attaches to the engine block. The 400CI is very similar to the 350CI. My guess is that one of the gaskets from the pump is leaking. Also, make sure it isn't leaking from the weep hole on the waterpump. Let me know what you find. And FYI, a bolt can break in the block at any time. You may want to spray the bolts with a penetrating fluid a couple days in advance.

Let me know if you have other questions.


Sorry, but that answer plain sucked. Please re-read my question. I asked on the specific procedure to replace the gaskets that go from the water pump, through the timing chain cover, to the water jacket in the block. This area is directly behind the timing chain cover. The Pontiac 400 and Chevy 400/350 are nothing alike when it comes to the water pump. I've replace plenty of 350 water pumps so I know. If your not familiar with this motor please let someone answer who is. Because you answer isn't even close to what I was asking.

I can send a picture to someone who is familiar with this engine.


Nov 30, 2009.
I will refer the question to another mechanic.