Smog pump fan removal

[Chuck Caldwell]

Need some help.....bought a used smog pump, hoses, etc for my 70 LT-1 restoration project underway

Can't figure out how to get the pump fan off without braking it....anyone ever take one of these off, how's it done? Doesn't look like any kind of "puller" will work....

Is it threaded on or pressed on the pump shaft..?

Any ideas or help would be appreciated.

thanks

Chuck Caldwell

[Joe L.]

Re: Smog pump fan removal

Chuck-----

The "fans" are a press fit on the pump hub (the part that the pulley retaining bolts thread into).

Depending upon the age of the particular fan installed on the pump will slightly effect the removal procedure. Early fans (usually white, but sometimes black) are actually a 2 piece part. In order to remove the fan, you first have to pull or pry off the outer "disc". Then, you'll be able to pull off the rear fan using vise-grip pliars and gripping one of the fan "blades". Basically, the fans are not designed for removal and re-installation. They were considered a SERVICE item and were designed for removal and replacement.

Some of the newer fans might not be of a 2 piece construction. All of this type will be black. For these, you just have to grip them anyway you can and pull them off.

For installing a new fan, use the pulley and its retaining bolts as a "press". Pull the fan onto the hub by turning down the retaining bolts so that the pulley "presses" the fan onto the hub. Do this EVENLY so as not to "cock" the fan on the hub and damage it.

The fans are long-since GM-discontinued but are available in the aftermarket and in reproduction (for the white versions).

[Chuck Caldwell]

Re: Smog pump fan removal

Thank you Joe for your detailed removal instructions....

Question 2 - It's my understanding that the "white" fans were used on the smog pumps installed for the performance motor applications, like the LT-1.. is this correct?

Any recommendations on where to purchase a replacement fan?

thanks in advance (again)

Chuck Caldwell

[Harmon C.]

Re: Smog pump fan removal

Chuck

If you want to remove the hub and the fan together I made a puller out of 1/4 plate with the three holes in it. Use bolts and the threaded holes and it will come off easy.You can then press it back on with no damage.

Lyle

[Joe L.]

Re: Smog pump fan removal

Chuck-----

The white fans were used on all smog pumps of the period. I don't know when the change to black occurred. I expect sometime after about 1973 or 74. I don't know anything about the reproductions.

[Chuck Caldwell]

Re: Smog pump fan removal

Joe and Lyle...thanks for sharing your input and experience on this topic.
Much appreciated!

Chuck