# Fan Shroud



## Chevythedog (Dec 13, 2019)

I need some advice please. My 67 GTO is not cooling well on hot days in town. Non AC car. Aluminum radiator, 165 thermostat, new HD clutch, shroud, and original looking fan. It cools wonderfully down the road. My fan does not fit in to the shroud very far. Measured and re-ordered what should have been a deeper stock shroud. It was the same as what I have. May have to go to a spacer and straight fan? I do not really want to switch to an electric fan. Will try to upload picture.


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## Lemans guy (Oct 14, 2014)

That shroud does look short did you get it from Ames? When you change radiators sometimes the distance changes. Also Hayden sells a few different clutches, some 3 inches stand-off some less.MSD you have to measure.


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## Lemans guy (Oct 14, 2014)

MSD is a typo ...you have to measure the depth of the fan clutch. Fan blade should be half in and half out of the shroud.


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## BLK69JUDGE (Jun 10, 2010)

that does not look like an original gto fan blades look wrong ....

also

what do you know about your water pump brand and impeller type ?
was the impeller clearanced to the plate ??








Air conditioning radiator rubber seals


Bought a seal kit from Ames with fasteners... thought I had all the parts to install... I've found:crazy: that I really only have the bottom metal pieces and not the side ones..... Any one out there have any ideas on where to finds these items..




www.gtoforum.com




Scott


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## PontiacJim (Dec 29, 2012)

Idle speed too low? Carb running lean? Timing incorrect? Vacuum advance working? Fresh air filter?

Verified engine temps with hand held infrared temp gun to verify gauges? Inlet/Outlet temps?


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## Chevythedog (Dec 13, 2019)

Thank you all that replied. I do not know impeller details. New shroud came from NPD, but they sourced it from Ames after I talked to customer service. Pontiac Jim, Holley Sniper installed. Hand held matches mechanical gauge with in a couple degrees + -. Cools great with a little air going through it. 98 degree 300 mile cruise, stayed around 187 - 195. Crept up to 220 in parade the other day, 95 degree outside temp. Cooled right down to 185 when I hit open road. Even if I could drop it 10 - 15 degrees in town I would be thrilled. Most would probably say electric pusher, but would rather not. If the fan was deeper in the shroud, would it make a big or little difference?


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## IceBolt (Jul 28, 2020)

Verify temperature with another source is an excellent first task. My '67 was running 220F+....260F in traffic. Put in a Cold Case system from Ames (Al radiator, new 165F thermostat, new water pump and high flow impeller, new fan clutch and new fan)......and added a new thermostat. All good and old thermostat still showed 220F.....new one = 185F. Looking back, i'm not sure what fixed the problem but old gauge was definitely off.


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## Chevythedog (Dec 13, 2019)

IceBolt said:


> Verify temperature with another source is an excellent first task. My '67 was running 220F+....260F in traffic. Put in a Cold Case system from Ames (Al radiator, new 165F thermostat, new water pump and high flow impeller, new fan clutch and new fan)......and added a new thermostat. All good and old thermostat still showed 220F.....new one = 185F. Looking back, i'm not sure what fixed the problem but old gauge was definitely off.


I have been tempted to try a different thermostat, cooler weather though it is pretty close. I really don't know what Aluminum radiator I have, was in the car already. Did it boil over before? If so, any idea what temp?


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## IceBolt (Jul 28, 2020)

It didn't boil over so that's why I think my water temp gauge was way off. As far as thermostat, i tried 165, 180, 195F....didn't see much difference. I believe the one with the cold case kit is a 165F....someone said to drill a couple of holes in it and that could help too. Will do that next time i change fluid. I made my own shroud to add on to factory one....will probably go to twin electric fans when I finish putting Vintage AC; put the condenser in front of radiato so could use some extra pull through at idle......this car is my daily driver and it gets hot in the Bay Area in summer!


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## armyadarkness (Dec 7, 2020)

All aluminum radiators are not created equal... neither are all water pumps. If you have a generic "amazon" radiator, it may be very inefficient, and if you have a generic parts chain water pump, the impeller may be stamped crap.I have a 67 in Jersey, 95 degree temps with 90% humidity, 3 hour trips weekly, no radiator gaskets, no shroud, no fender well covers, and I rarely break 180 degrees.

Cold Case radiator, Flowkooler pump, modified thermostat, new hoses, acid washed system, flex fan, no garden hose fill ups.


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## Banjos (May 10, 2021)

Your fan looks like it's barely in the shroud. Should be half in/out. Here is the set up on my '65 non A/C Lemans. It has the same Ames shroud with Cold Case radiator, Hayden clutch and Derale Fan. It has a 455 out of a '72 Firebird with the longer water pump so I had to go with a shorter clutch.


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## nick rice (Nov 10, 2014)

I had to go take a look at mine. 66 non ac. I'm not 100% sure if mines the orig or correct 7 'aluminum blades' fan or not. It looks like it's barely inside the shroud like yours but I've never had a cooling problem in 10 years so I'm leaving it. I see you have no top shroud guard on the core support, isn't that standard for all non ac cars in 67 like 66?

Sent from my SM-G970U using Tapatalk


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## 67 ragtop (Jun 15, 2020)

Chevythedog said:


> I need some advice please. My 67 GTO is not cooling well on hot days in town. Non AC car. Aluminum radiator, 165 thermostat, new HD clutch, shroud, and original looking fan. It cools wonderfully down the road. My fan does not fit in to the shroud very far. Measured and re-ordered what should have been a deeper stock shroud. It was the same as what I have. May have to go to a spacer and straight fan? I do not really want to switch to an electric fan. Will try to upload picture.
> View attachment 143598
> View attachment 143598


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## 67 ragtop (Jun 15, 2020)

How's it going today? Not sure if you have gotten the answer yet but what I see in the photo
it kinda looks like the fans diameter is small for the shroud. I have a 67 LeMans with a 326 and
I put a fan from OPG a heavy duty flex fan Pat # L201359 and made sure the fan was in the shroud half 
way in. You will have to measure for the spacer for proper depth. I have had no problems works great.
Hope this helps. You need to get the air to cross the radiator fins or it will never cool. Good luck


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## PontiacJim (Dec 29, 2012)

On board with others, the fan looks too far out from the shroud/radiator core. Looks like a factory fan as the fan pitch has a fairly high angle.

You can get spacers, the factory did use them as well, that will fit between the outside of the pulley and locate on the water pump dowel that sticks through the pulley. You want to make sure your spacer is designed to fit over the water pump dowel and also have an alignment down on its other end that you are going to bolt the clutch fan back on to. This will align/center everything. You will need longer bolts as well for use with the spacer.

You want the fan blades 1/2 in, 1/2 out IF you can. Just watch the clearance between the front of the fan's clutch and the radiator core. A quick guess would be it looks like a 1" spacer may do the trick?

Check out Post #10 with the pics to give you reference. Says it is a 1" spacer and fan clutch is 1 1/2" from radiator.

The spacers are different styles, non-clutch fan vs clutch fan spacers. These are listed for clutch fans.






1964-1972 GTO Restoration Fan, Fan Clutch, Hardware and Spacers Parts - National Parts Depot


Shop Fan, Fan Clutch, Hardware and Spacers for your classic 1964-1972 GTO at NPDLink.com! Free shipping over $300, fast delivery & everyday low pricing!




www.npdlink.com





The item mentioned missing on your car is called a "finger guard or fan guard." This would not hurt to add, just make sure you get the correct one. Not sure if there is a left/right cap hole, but it may be due to the year or radiator type?









65-67 Pontiac GTO / LeMans Fan Guard / Finger Guard - Steel OEM - Left Hand Hole | eBay


This is the steel guard that covers the fan blade on the core support. It is OEM replacement. The hole is on the left side. This guard comes with the correct bend on the lower right hand corner (shown in picture). Fits 1965 / 1966 and 1967 GTO / LeMans models.



www.ebay.com


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## Teknoid (Mar 25, 2021)

Chevythedog said:


> I need some advice please. My 67 GTO is not cooling well on hot days in town. Non AC car. Aluminum radiator, 165 thermostat, new HD clutch, shroud, and original looking fan. It cools wonderfully down the road. My fan does not fit in to the shroud very far. Measured and re-ordered what should have been a deeper stock shroud. It was the same as what I have. May have to go to a spacer and straight fan? I do not really want to switch to an electric fan. Will try to upload picture.
> View attachment 143598
> View attachment 143598





Chevythedog said:


> I need some advice please. My 67 GTO is not cooling well on hot days in town. Non AC car. Aluminum radiator, 165 thermostat, new HD clutch, shroud, and original looking fan. It cools wonderfully down the road. My fan does not fit in to the shroud very far. Measured and re-ordered what should have been a deeper stock shroud. It was the same as what I have. May have to go to a spacer and straight fan? I do not really want to switch to an electric fan. Will try to upload picture.
> View attachment 143598
> View attachment 143598


I had terrible temperature problems with my ‘67 GTO. I tired everything that has already been mentioned in the replies to your posting. It finally came down to the clearance between the water pump impeller and the plate (this was mentioned in one of the replies). I removed the water pump and put the plate in a simple press. I reduced the clearance to approximately 1/16” (0.0625”). This did the trick! Runs nice and cool now. From what I could tell in my research this is a common problem. The coolant cavitates in the water pump and won’t circulate properly though the system. The proper fan shroud and a clean radiator help too.


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## lust4speed (Jul 5, 2019)

Seems like a lot of people here line the 1/2 and 1/2 positioning, but my GTO and others I have seen with the original pump, fan clutch and fan, are 1/3 in and 2/3 out. This applies to both the AC cars that came with a shroud or to cars where the shroud was added to a non-air car. My '67 H.O. that I factory ordered didn't come with a shroud and it was less than two weeks old when I went back to the dealer and bought a shroud (it was $11 and some cents back in early 1967).

I would say that the OP's fan has a different front/rear offset and not really suited for his Pontiac since the fan sits too far to the rear.


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## Chevythedog (Dec 13, 2019)

nick rice said:


> I had to go take a look at mine. 66 non ac. I'm not 100% sure if mines the orig or correct 7 'aluminum blades' fan or not. It looks like it's barely inside the shroud like yours but I've never had a cooling problem in 10 years so I'm leaving it. I see you have no top shroud guard on the core support, isn't that standard for all non ac cars in 67 like 66?
> 
> Sent from my SM-G970U using Tapatalk


Good to know. I will check that out. Thank you.


PontiacJim said:


> On board with others, the fan looks too far out from the shroud/radiator core. Looks like a factory fan as the fan pitch has a fairly high angle.
> 
> You can get spacers, the factory did use them as well, that will fit between the outside of the pulley and locate on the water pump dowel that sticks through the pulley. You want to make sure your spacer is designed to fit over the water pump dowel and also have an alignment down on its other end that you are going to bolt the clutch fan back on to. This will align/center everything. You will need longer bolts as well for use with the spacer.
> 
> ...


Very good info, thanks Jim


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