Red 409 63 impala
Well Known Member
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409 Fan Question
- Thread starter Red 409 63 impala
- Start date
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Red 409 63 impala
Well Known Member
I was wondering if this fan is installed correctly? Always wondered if it should be either a pusher or puller? I always thought you would want to pull outside air thru the radiator. The assembly manual looks like the long straight fan blade goes toward the engine side.
The fan blade needs to be 1/2 in and 1/2 out of the fan shroud.
Red 409 63 impala
Well Known Member
Well I noticed the post about the fan being half in and half out. Looking at mine it is not. On mine about 1/4 of the fan is out. I have the correct shroud it is new. The fan is new as is the fan clutch. I believe the water pump is the long style. My thought is I should have the short style. I have the bypass hose..Did the 409 have both type water pumps? With the bypass hose available?
Since the photo’s show no radiator. I believe the shroud has spacers at the radiator bolts holes to move the shroud to the desired location for the half in half out.
Dave
Dave
Red it appears your water pump is short as I believe all W pumps were does your water pump pulley line up well with the crank pulley?If your pump is a rebuilt original the disassemble the shaft and press it back together on reassembly the pulley mounting flange does not always get positioned correctly so look at that if you have alignment issues.
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Junky
Well Known Member
Visually from my view of your pictures, it looks correct. When you obsess over the small details of 1/2 of the fan blade being exactly 1/2 out of the shroud, you will drive yourself crazy. Just put it together, and drive it. If there is a cooling issue, then you can address it, however, from what I am seeing, everything appears good. Oh, the gloss of the black paint has 13.5% too much gloss. I suggest that you take the pulleys and shroud off and repaint them. I obsess over the larger details such as paint gloss, and bolt heads that are gold iridite, instead of cadmium plated. These finish details are the type of details that really make the car go faster!
Red 409 63 impala
Well Known Member
Well I removed the pulley to check the casting # 3755787. That shows as the correct pump (short). It does appear that the water dump mounting collar is positioned incorrectly. It sticks out slightly less than 3/8 in. I have looked but, can not find a spec for that distance. Can that collar slide up or down the water pump shaft?. By the way I do remember that using gloss paint on the shroud increases gas mileage by .000001 mpg due to less wind resistance. (lol)
Junky
Well Known Member
If the water pump pulley flange was installed too far onto the shaft, you might be able to pull it out using a small 2 arm gear puller. Put a piece of tape exactly where you want the flange to stop at when you are pulling it. The only other choice is to remove the water pump, and put the pump in a press, supporting just the flange, and pressing it towards the end. Problem is that if you go too far, you will need to disassemble the water pump, and then press it back to where it belongs. I would put a belt onto the pulley before doing anything, and check to see if everything is aligned, and / or how far it is off. If you decide to remove the pump, when you reinstall it, consider using the round spring clamps, instead of the worm gear clamps. The round spring clamp is known as a Corbin clamp, and why I like them, is that they provide constant pressure, and also that they are period correct. Yes, they are a pain to install and remove without the proper tool, so also purchase the proper tool if you don't already own one.
Red 409 63 impala
Well Known Member
Thanks to old sky dog I measured the location of the hub for the pulley, it is right on. I also noticed that I can not move the hub back because the pulley will hit the pump. So I guess I will just live with it. The fan clutch is a repo as is the shroud. I thinking one these repo items could easily be off and causing this.
If the pulley's line up, I would give it a try and see how it pulls air and cools it.
Red 409 63 impala
Well Known Member
The pulley’s do line up..I noticed up closer inspection that the fan shroud does not look right. Measuring on the top at the front of the brackets and at the rear there is a difference of over 1/4 inch, causing it to look bowed out. Measuring the mounting holes the distance between the mounting center varies almost 3/4inch. Another case of a repo part being a piece of crap!.