Timing Covers & Water Pumps

66P51GT

New Member
Nov 7, 2003
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Cerritos, CA
I have heard there that specific timing covers are necessary for specific water pumps. In particular...

Early Model: Cast Iron Water Pump
Early Model: Aluminum Water Pump
Late Model: Reverse Rotation

I have the original timing cover off of my '66 that I just bead blasted. I compared it today from the one off my '90 5.0. Everything appears identical in the water pump mounting location including the inlets in and out of the water pump, bolt patterns, and depth behind the water pump.

Years ago I replaced my early iron water pump with an aluminum one and didn't know of a difference between the timing covers and ran it for 120,000 worry free miles.

What gives? If somebody really knows the difference, please reply.

Thanks!
-Chuck
 
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Well, I have a late model cover with an early model iron water pump, drivers side though. I was haveing trouble getting a drivers side aluminum that wasn't reverse rotation. I'm pretty sure if the holes line up it will work. i think the only diffrence is passenger side and drivers side pumps maybe :shrug:
 
The early aluminum pumps used a timing cover where the bottom of the pump mounting surface was smooth and straight.
The later versions, cast iron, were nearly identical except the bottom of the water pump mating surface was 'scalloped' inward toward the impeller.
So, theoretically they should not interchange, due to different gaskets/mounting surface, they just might. I have never tried to mix match.
Other than this, all the other differences are more superficial, like changes in dipstick locations, timing pointers, and oil fill tubes found on some earlier versions.
Also, some have no provision for a mechanical fuel pump and very early versions have a road draft tube for case venting.
Dave
 
I had 3 covers in the garage side by side, one from a 1972 302,an 84 351w and an 88 302 H.O. and the only difference I could see was the location of the timing pointer, type of front seal,provision for a dipstick and on the 88 cover the fuel pump boss was there but was blocked off.
 

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351LX said:
I had 3 covers in the garage side by side, one from a 1972 302,an 84 351w and an 88 302 H.O. and the only difference I could see was the location of the timing pointer, type of front seal,provision for a dipstick and on the 88 cover the fuel pump boss was there but was blocked off.
Considering the SBF went from 62-98(?), you have some time frames not represented in your selection. The 20 years missing is more than half the engine's existence.
Your latest part still has a fuel pump boss, your earliest part was 7 years after they stopped using aluminum water pumps and oil fill tubes.
There are distinct differences not represented.
Dave
 
I attached 2 other examples.
I was looking for a pic of the version with 2, yes 2, fuel pump mounts... one on each side.
 

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Timing cover on left is from the '66
Timing cover on the right is from the '90
The '66 had an iron water pump.
The '90 had a reverse rotation pump.

The '66 has a mechanical fuel pump boss, hole for the dipstick.

In this case, it appears I can use an aluminum standard or reverse rotation pump.
Left '66 Right '90
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The aluminum pump pic is around 63-64. A year sooner would have the road draft, a year later wouldn't have the fill tube mounted on the timing cover.
The late model cover was put into use around 94 till the end of 5.0 production.
 
I find it amazing that you can look at the water pump section of the cover and see that it is very similar in design for the first and last 5 years of the SBF's 40. The 30 years in the middle were quite different.
It's like they came full circle with aluminum pumps.