http://www.corvette-paragon.com/images/1pxSpacer.gifhttp://www.corvette-paragon.com/images/1pxSpacer.gifhttp://www.corvette-paragon.com/images/1pxSpacer.gifENGINE FAN CLUTCH UNITPR #: 714GM #: 3916141Engine fan clutch unit, 5/8" arbor hole, 1 3/4" bolt center. Visually, this part does not look exactly like the original style, but it is quite close.
For Years:1960 to 1970
Condition: New
Packaging: Each
Additional Notes: We can rebuild your original fan clutch unit. Ask your order taker for details.
Type: Stock



http://www.corvette-paragon.com/images/1pxSpacer.gif http://images.corvette-paragon.com/714_standard1.jpg
http://www.corvette-paragon.com/images/productZoomImage.gif Qty:

Your Price: $125.00



It's from Paragon Corvette.

Think this is for the short leg BB water pump that was on the 66-68 chevelles. That water pump was also used on 60-70 corvettes. But in 69 the chevelles got the log leg water pump. Isn't the bolt pattern of you water pump, if you have a 69 BB water pump larger than the 1 3/4. And I think the fan hole and bolt pattern for a 69 fan is different. What water pump do you have and what fan blade do you have and how much clearance do you have between the water pump pulley and the radiator and do you have a fan shround?

James,

I have a Stewart Stage 1 water pump, which from the exterior is a direct stock replacement. I have the 7 blade fan, and will have the factory fan shroud. I plan on purchasing an Alumitech Rad, which are direct bolt-ins.

I believe the fan clutch you are looking at has a water pump flange that is 2 5/16" in diameter and a 1 3/4" bolt pattern and is made for an original 66-68 chevelle BB fan blade with a center hole of 2 3/8" and a bolt hole pattern with a 3" diameter.

I don't know which 7 blade fan you have; but it could one for the 66-68 chevelle or be the one for a clutch with a 2 9/16" water pump flange and a 2 1/8" bolt pattern an is a fan with a 2 5/8" hole and a 3 1/4" bolt diameter. The original 69 chevelle BB fan had the 2 5/8" hole and the 3 1/4" diameter. Maybe your fan is an aftermaket that has 8 holes for both patterns.

If you have a steward stage 1 water pump it might have both the small (1 3/4" diameter) and large (2 1/8" diameter) bolt patterns on the hub, so it fill fit all years.

I think the clutch at paragon has a distance of 1 1/2" from the water pump flange to the surface where the fan blade mounts.

Just because the water pump bolts in place doesn't mean the steward warner pump you have puts the water pump pulley in the exact same place as an original application. Does SW make both a short and a long pump? If so which do you have?You need to determine the distance from the water pump pulley to a point inside the fan shroud, so that the fan blades are about 1/3 inside the fan shroud. If you set the fan to far inside the shroud it will not pull air as it should. Alumitech has different options as far as radiators. If the factory shroud (I think you might mean a reproduction) along with the radiator sits exactly in the original position, and you have a long leg pump this clutch could work, if the water pump flange fits your pump, it puts you fan in the correct position and you fan blade fits. Good luck

Is this the water pump you have?http://www.stewartcomponents.net/Merchant2/merchant.mvc?Screen=PROD&Product_Code=11113&Category_Code=ChevyS1
If you notice it has a clutch hub that has both bolt patterns, so with fit a number of fan clutches.

What you need to do is determine is if this fan clutch fits your fan blade and if it puts the fan blades the proper distance inside the fan shroud. http://www.parts123.com/parts123/yb.dll?Parta~ShowPicTxt~Z5Z5Z50000358f~Z5Z5Z5FACTU ~Z5Z5Z51

Dan that is likely a thermostatic fan clutch for up to 68 short pump in std pass cars with bbc but vettes had short pump thru 70 with bbc and its a std non ac clutch too. But even if it was the correct std duty fan clutch i would not use and here is why.

I find they are not that good at cooling bbc on hot days(they are marginal), but the ac/hd type fan clutches(not severe duty/too noisey & for trucks) do a much better job of cooling with minimal increase in fan noise which is hardly noticeable ,my car is not that loud so i would have noticed if the fan made considerably more noise while at cruise with the hd clutch on my car but it was not that much louder in my case.

I experienced this 1st hand from going from a std duty to HD/AC type thermostatic clutch when we had the 100deg hhh heat wave a while back to a hd/ac type thermostatic clutch. The h/ clutch looks basically the same as the stock std duth fan clutch. But the hd clutch locks up a little sooner and also lock up more for increased fan rpm resulting in more airflow thru the radiator and it also has some more fins on the front facing the radiator to better cool the hd clutch which you cant see when installed so nobody would know its the HD fan clutch insted of the stock std duty clutch accept for you.

I have since talked 2 other people into switching from std to hd/ac type thermostatic clutches and they were both very pleased with the additional cooling it gave them,1 was a mild bbc and another a ram air 4 gto i stock form.

Dont get me wrong the std duty therm fan clutch will work but its marginal cooling on hot days when in stop/go traffic,or when crusing at slow speeds like 25-35mph in town,or when finally getting up to cruise speed after being in traffic for a while and it takes longer to get it cooled back off as when compaired having the hd/ac fan clutch,wished i had made the change earlier.

Here are the correct hd fan clutchs to run with a stock gm 7 blade 772 fan thats correct for your 69 . BTW,dont forget to run a shroud and if at all possible a hig flow w/pump and hi flow 180 deg stat. If you looking for originality like i do then find a correct original 065 w/pump thats never been rblt so it still has the orginal better flowing cast iron impeller and have it rblt/restored or get an already rlt original that i see once in a while on ebay. But make sure to ask if it still has the original cast impeller or if it has the std replcaement stamped steel type impeller many pumps get these days thats oinferior to the better flowing/pumping cast iron impeller.

These hd cluthes look close to the originals,nothing way out of place that i can see.

Napa-271303 - H/D

Hayden-2747 H/D

Scott

Dan,I have a non thermal clutch on my 70 SS454 that looks like the one from Paragon and it cost about $25-30

3916141 is for the short water pump.
I have this clutch on my car with a rebuilt original water pump and recored original radiator and fan shroud. The motor is stock except for a different camshaft, and I don't have any cooling problems. In traffic on hot days with the A/C on, the factory temp gauge reads around 5/8 to 3/4, since it's not graduated in degrees I have no idea how hot that is.
BillL
BillL

Trust me i do have an aftermarket autometer mech temp gauge in my 396 and and saw 1st hand that the std duty fan clutch doesnt cool as well as the HD/AC version does,period. In the 100 deg heat wave we had a couple wks back here in NY the HD/AC clutch dropped my engines temps from 210-215 deg f when in basically still traffic for 8-10 mins (on thoses HHH days) to 195-200 tops and then cooled back down 2x faster when leaving the stopped traffic and getting up to speed again,made a big difference.

I experieced this not only with my car but 2 other cars that i mentined in my 1st post here that had std duty fan clutches that were not very old lwhen they switched to the hd/ac type clutch. With the hd/ac clutch they also had reduced temps when in traffic and faster cool down when leaving traffic getting up to cruise speed again and were very happy with the swithc to the hd/ac fan clutch which is the same result i had.

I dont care for the non thermal fan clutches because they cant lock up more when the motor gets hot in traffic and only have one lockup speed unlike a thermal type hd/ac fan clutch that can lockup more when required as temps rise but isnt locked up as much when engine temps are lower saving fuel and power. The non therm fan clutch is also running when the motor doesnt need the additional cooling at lower speed on a cool day,thats why it's just not as good as the thermal clutch IMHO . It wastes fuel & power/perf because its running when not needed,but they obviously work ok with some setups and have their place,just not on my car. (LOL!!!)

That Paragon clutch is $125 and the hd/ac napa clutch is approx $70 which s $55 cheaper for less cooling capability,its an easy choice in my mind and you really cant tell the dif when the clutch is installed . But if your car will never be seeing much traffic then go for the more expesive clutch that wont cool as well,thats up to you.

Scott

Scott, I don't doubt your word one bit about your experience. :)
I'm in Arkansas, where high summer temps are normal, and I was just relating my experience. Dan's in Ontario, so he won't see hot summers either, unless he travels south. These cars didn't run hot 40 years ago, and I believe that if you're running a stock motor and build your car with the correct radiator, shroud, fan and clutch, and have the timing and jetting right, the car won't overheat. That's the way mine's built, and the temp gauge doesn't show hot in Arkansas summers with the A/C running. Warm, yes, but not hot. ;)
This being the "originality" forum, I was letting Dan know that the part he pictured wasn't correct for a '69 Chevelle. I will also say that the NAPA fan clutch is easily distinguished from a GM original due to the slotted mounting holes.

BillL

Thank you to everyone for your well explained responses, I definitely learned a few things here!

Bill,i hear ya and i also mentioned that was the wrong clutch for a 69 too.

BTW,thats a real nice 68 you have there.

Slotted mount holes on the napa clutch? You really cant see much of the clutch at all when its mounted ,only a little of the fins. Maybe that slot your reffering to is on the end facing out so it can be seen when looking at the fan to clutch interface from the side,i will have to chk that out.

I never wanted to give the impression the std duty fan clutches cause the motor to overheat which it didnt in my case or the other 2 friends of mine i talked into going to the hd fan clutch. But we all had the same situation when in traffic on hot days our motors would creep up to205- 210 or even 215+ in bad traffic which was marginal/not good and thats when i decided to try the hd/ac fan clutch and that helped alot for all of us. Now in same traffic situation my motor went from 210 in moderate traffic to 195-200 max which was a sig improvement for a 15 minute bolt on and the other 2 guys had similar good results.

I was just thinking since the dif between the gm and HD Napa rep clutches aren't that apparent when installed in the shroud facing the rad where you cant see it very well then why not use a clutch that will cost sig less and do a better job of cooling when needed the few wks a yrs its hot where he lives. Thats what so nice about the thermostatic clutches ,the std duty and HD clutches have very close non locked up rpm but it's when the motor gets hot in traffic and the fan clutch locks up more for increased airflow/cooling that the HD clutch does better . Thats due to an increase fan rpm when the HD clutch is locked up resulting in increased airflow/cooling. Its a win win situation when using the hd clutch without it being real obvious like maybe a Walmart battery under the hood . That always gets me when someone spends 25-30+k restoring a chevelle ss 396 to perfection and they they install an Optima or Walmart battery or even a battery topper thats usally easily spotted & they all stick out like a sore thumb under the hood,whats up with that?

My 69 /396/m20/3:31's is a #'s matching survivour which i have owned for over 30yrs so i am definately into the looking right thing too,so i know what you mean there. The car has all the original chrome/bumpers/interior/wheels/drivetran,etc. I had it repianted the original dusk blue in 2001 and i also rblt the motor at that time. The motor still ran pretty good at tha time but the main seal and pan gasket were leaking so i pulled the motor and spent $3800 on parts and maching work going thru it completely. I did all engine dissassembly/assembly myself,but other then that its never been formally restored. Gee,I even went for the repop R59 8 yrs ago and now the maintfree SR59 after the 1st Rr59 died so you know i have to be serious about it looking right to pop for those pricey batteries when i am defiantely not loaded with dough . (LOL!!!!)

My setup is basically stock with the exception of 1 thing which is a very mild flat tappet hyd perf cam thats a tick hotter then the L34 396/350hp had but still idles well and it would take a good ear to tell the cam is a little hotter.

Have fun driving your great looking 68 to the shows in your area.

Scott

NAPA fan clutch vs OE fan clutch--slots/no slots where it mounts on the water pump pulley.
BillL

Thanks Bill,very nice pics,those slots were just where i thought they would be at the clutch to fan interface. Now all in t/chevelle can see what your talking about so they can see the difference and can judge which way they want to go from there and if its important to them or not,pics can really help out in situations like this.

Scott

Dan I am running a Stewart Stage 1 , Hayden HD Clutch, Alumitech Radiator, and a stock 772 Fan. The air and water flow are amazing. Fit is perfect on my 69 SS and I have A/C.