Whats wrong with this picture?

[The73vetteman]

The fan on my car has never fitted into the shroud. Please check out the attached picture and tell me what's wrong.

(My suspicion is that the water pump is much skinnier than the stock unit, but perhaps someone could confirm this?)

Thanks, John

 

[Tom73]

Simple, you are missing the shroud extension.

Should have an extension like this:

tom...

 

[George Black]

Tom is correct. You are missing the radiator shroud. They are expensive if obtained new. I have seen used shrouds on E-bay. Also several of the corvette used part dealers usually have them. You need one in my opinion. They will prevent overheating.

 

[Vettehead Mikey]

Even if you get the shroud extension, your aftermarket 'flex fan' may not fit. The previous owner may have ditched the shroud for that reason.

As a suggestion, you may want to get rid of the flexible rubber hosing going from your fuel pump to your carb. It should be a solid steel line. Rubber hoses with pressurized fuel inside near a hot engine are a disaster waiting to happen.

 

[The73vetteman]

These seem like sensible suggestions. Thanks guys.

Is it possible to change the fan for an original item without removing radiator/engine?

Mikey - any suggestions where I can get a steel fuel line?

John

 

[George Black]

John: All the major corvette suppliers should carry the OEM fuel lines. They are not expensive--in fact they are very reasonable. I believe ZIP, Corvette Central, Ecklers, etc. all carry the fuel lines. Very easy to install.

You should be able to install a stock fan, and fan clutch if needed, without pulling the hood, raditator, etc.

 

[GaryS]

These seem like sensible suggestions. Thanks guys.

Is it possible to change the fan for an original item without removing radiator/engine?

Mikey - any suggestions where I can get a steel fuel line?

John

Changing out a fan is an easy DIY job. No need to take the engine out. Unbolt the fan, pull it out, install new fan. Simple. Obviously some belts will have to be loosened but this is a real simple one, providing you can find the right fan.
Gary

 

[Space Cowboy]

If you're still going to shop for a shroud extension (which I think everyone here would agree you need), I found that Davies Corvette had the best deal for a new one. Speak with Jackie... she great to work with.

GaryS is correct... changing the fan is a breeze. Just loosen the alt. and pull the belt. One safety tip... watch those flex fans, the will cut up your arm if you're not careful.

Good Luck!

 

[Vettehead Mikey]

Mikey - any suggestions where I can get a steel fuel line?

John

Any of the suppliers have them. Dr. Rebuild is a particularly knowlegeable source.

 

[ruby76]

two water pump sizes

I can't believe no-one has mentioned:

Chevrolet made two sizes of water pumps. A long shaft and a short. Looks like all the pictures on this thread have the short shaft water pump. The fan shroud extensions make up for the shorter water pump. The longer pump was "fins" for extra strenght and are easy to recognize. Take a trip to autozone (or maybe their website will have pics) and you can see the difference. There is about 3 inches (give or take) between the two.

It would probably be easier to get the shroud extension as otherwise you'd need a "deeper" crankshaft pully and same for the other belt driven accessories.

Jeremy

 

[Space Cowboy]

Ruby76... you are correct, but it depends if you have a 350SB or 427BB determines which water pump you need. If I recall on my new 427BB I had to purchase a short water pump because of the larger engine size. If 73Vetteman has a 350, he would need a long water pump I think.

 

[Vettehead Mikey]

I can't believe no-one has mentioned:..................

That's probably because your comments are not quite correct and not relevant to the question.

There's actually a THIRD pump, and the only pump that is correct for a small block Corvette. It's very similar to the 'short' pump, but has a larger diameter spigot for the pulleys to fit over.

It appears that the pump installed is the correct one. Verifying the casting number to be 100% sure might be difficult without removing the pulley.

 

[Space Cowboy]

I found this in another forum just for information:

Small block chevys used short leg water pumps on all passenger cars thru 1968 and on all Corvettes. The mounting surface of the leg(block side) to front of pump housing(non outlet side) is roughly 2 inches. Big block chevys used short leg pumps from 1965 thru 1968 and on all corvettes. Pumps after this time were long leg design. Mounting surface of the leg to front of pump housing(non outlet side) is roughly 4 inches. Note: Though the name is the same, the small and big block pumps are not the same. Big block pumps have a bypass provision on the top of the pump, little blocks do not.

 

[ruby76]

So you say there are 3 sizes of water pumps for small blocks?

I know of 2 sizes for smallblocks and only 1 for big block, the small and big block pumps are not interchangable. I was unaware of a third smallblock version.

When I say long vs short, I mean from where it mounts to the block to the flange where the fan bolts on.

It is true what they say, you learn something new everyday

 

[ruby76]

water pump size (short vs long)

We'll see if this pic comes through. I found it on another thread in the C3 forum. It is a picture of the long and short water pump for a small block chevy side by side. If anyone one has a 'vette one to compare to I'd like to see it. Inever knew corvette had it's own water pump! (picture originally posted by bossvette)

I also found the following text on another forum here as well and has some dimensions:
http://www.corvetteactioncenter.com/forums/showthread.php?t=55401&highlight=water+pump

Posted by 1979toy
"The small block Chevrolet engine used one of 3 water pumps over the years. They are referred to as short, Corvette, and long. The short and long pumps used a 5/8th inch diameter pilot shaft at the fan attachment. The Corvette pump used a ¾ inch diameter pilot shaft to mate to the fan. Measuring from the mating surface to the block to the point where the fan attaches the pumps measure;
Short – 5 5/8ths
Corvette – 5 13/16ths
Long – 6 15/16ths"

 

[curtis]

Make your own extension from aluminum sheating. Pop rivet the new extension to the original shroud (make sure rivets don't hit fan) and you wil have an attractive functional addition to the engine compartment. the extension should cover no more than 2/3 of the width of the fan blades for optimum cooling.