BBC water pump trouble

ToniH

Well-known member
Joined
Apr 2, 2008
Messages
49
Location
Finland
Hi,

I was going quick, 5000+rpm at 3rd gear when I saw a small puff of something it my rear view mirror. Upshifted and accelerated some more but then I got a feeling that something is wrong and I eased off. When I was back at about 60mph I started to hear intermittent and loud knocking sound. Was getting worried and pulled over. :cry:

When I opened the hood I saw some steam and there was fluid all over front of engine, suspension, radiator and even inside of the hood. Engine fan had clearly thrown the fluid all over. Luckily it looked and smelled like coolant. All hoses are ok so I touched the fan. Feels almost like its held there by the belts. The knocking sound came from the fan hitting the shroud.

I think I broke it... [ame]http://www.youtube.com/watch?v=6VaUV9A3IoI[/ame]

At this point I called a flatbed to pick me and the Vette up while thanking my luck.

Investigated BBC water pumps last night. Steward and Edelbrock seem to be the ones people like. By chance my local speed shop (here in North Europe where BBC water pumps are a rare find) has one of the Edel 8850 pumps. Will pick it up tomorrow and hopefully I'll get the Vette fixed soon.

Any pointers on the job ahead? How to make sure the new one lives a long time. I don't have AC so only alternator and PS pump. I am planning to convert to electric fan also.
 
You might want to consider an new belt routing. Three belts pulling in the same side of the pulley has got to put a lot of force on the WP bearing.
 
Hmmm... Its like this now:

There is 3 belts:
1. water pump - crank
2. water pump - crank - PS pump
3. water pump - alternator

Cannot remember what the stock PS pump bracket is and cannot find any good pictures of it. Is there some adjustment for tightening the belt? If I change it so a short belt is run from crank to the PS pump can I tighten it somehow?
 
Stock configuration for the 70 BBC w/o AC or AIR pump is:

Inner belt=Crank/water pump
Second Belt=Crank/water pump/PS Pump
Third Belt= PS Pump/Alternator. Power steering pump should have a 2 groove pully.
 
Aha! Thanks for that info.

Mine is now like this:
Inner belt=Crank/water pump
Second Belt=Crank/water pump/PS Pump
Third Belt= Water Pump/Alternator

And the PS pump indeed has 2 groove pulley. So, it would be wise for me to get a short belt and change the 3rd belt like the original (if the pulleys line up ok).
 
Stock configuration for the 70 BBC w/o AC or AIR pump is:

Inner belt=Crank/water pump
Second Belt=Crank/water pump/PS Pump
Third Belt= PS Pump/Alternator. Power steering pump should have a 2 groove pully.

:hissyfit:

How in hell you going to adjust tension on inner belt if all you got is crank and w/pump?? :nuts:
 
Not uncommon gene, just get a belt that's a bit tight and then wrestle the pulley on the WP.
 
Looks like the AIR pump belt tension opposed the tension from the crank/WP (RPO N40)

44ec3d88b59e67.jpg
 
BBShark: your pic is for older BBC cars with 427. Mine is 454 and I will post a later AIM page.
 
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This one is from my 1970 AIM. Note: no tensioner in my configuration. It seems there is 6 variations of belt routing during 1970 and 454 engine alone. I'll post them later.

ettnjm.jpg
 
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Here are all possible belt routing/pulley variations from 1970 454 engine with different options. AC cars have an idler, others do not.

25f69at.jpg

My current belt routing configuration is none of the above. This might have contributed to the failure.
 
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Here are all possible belt routing/pulley variations from 1970 454 engine with different options. AC cars have an idler, others do not.

25f69at.jpg

My current belt routing configuration is none of the above. This might have contributed to the failure.

:hissyfit: I just have to laugh, how many ways can the .gov fuck up a simple engine???

bad enough with/out a/c and p/s but to go ape shit over it??

:hissyfit::hissyfit::nuts:
 
The tensioner came with AC as the configuration shows. I don't see why you can't add one on the set-ups w/o AC. Should make it easier to get the belt on.
 
Well, not so easy to find such parts laying around here in Europe.

But lets first see if there is a problem or not. I haven't had any belt slippage problems yet and haven't tried to change a belt on the 454 yet. After I've broken few fingernails or fingers while trying I am sure to investigate this further ;)
 
The N-40 RPO is the same as Ol' Red's. You have to really careful to get the correct belt since it's not adjustable. Too tight, it smokes the water pump bearings and loads the front of the crank. Too loose, you might as well not install it.
 
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