Fan Clutch, do I have some sort of problem?

I have not had a car with a non-electric fan in a long time.
I have noticed that the fan is on and does not disengage until the car is warmed up....or I hit 40 mph.
I would have thought it would be the other way around. The car does not get hot, and actually runs very cool.

My complaint is the noise. Sounds like the car is ready for flight.

Anyone else having a similar issue, or is it just me and my OCD to vehicle noises? I hate rattles and pops and squeeks in a car.

iirc to check if its working correctly is to have eng up to op temp at idel turn eng off, the fan should only make like 3 revolutions then stop,any more its bad, sometime when i take off when its cold it sounds like a jet

The mechanical fan is driven by a silicon fluid-filled clutch. Normally, when the clutch is cool, most of the silicon fluid is stored in the reservoir allowing it to slip and spin at reduced RPM to reduce horsepower drag. As it heats up, the thermal spring opens a valve allowing the fluid into the space between the plates which engages the clutch and spins the fan faster to increase airflow through the rad and prevent overheating.

That said, after sitting with the engine shut off, gravity often drains the reservoir into the grooves between the plates on the bottom half of the clutch, so the clutch is mostly engaged for a few moments after starting, until centrifugal force redistributes it. As the fluid refills the reservoir, the fan slows down and that starting "roar" typically falls off.

If everything is working properly...

ill be damned after all these decades never knew about the fluid part,figured the coil had something to do when things got hot.. guess you learn something new very day

I found this cutaway drawing on the web:

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One of those things I took for granted.

Thanks for the advice guys. I was going to spend this weekend giving it a good once over. I am taking her on her first "long" trip the first weekend of November. (182.2) to be exact....and then back + driving around Flagstaff AZ.

I have taken it on 2 135 mile trips....short to us. We do that one 6 times a year.

Need to give a good once over on the brakes, and then pull some plugs...smells a little rich.
Not sure what else to do really. I feel confident driving it that far. Me messing around with anything will probably make things worse. I always find 30 things that NEED (not really) to be fixed RIGHT AWAY (probably in next year or so).....I think everyone reading this does the same thing.

.........as for the fan. BUICKWAGON thanks for the advice. That is exactly what I am experiencing. Now I can ignore the "jet engine" sound for the first 5 minutes of my 10 minutre drive to work.

5 minutes is a bit long. 30 seconds is more typical. But as long as the clutch passes inspection (no more than 1/4" wobble at the fan blade tips, no more than 2 or 3 turns when spun by hand cold, no roughness in the bearings) then I wouldn't worry about it.

Same here, the old Original clutch didn't make any noise on cold startup. After around 140K miles I had to replace it. Bought an aftermarket clutch which indeed sounded like a jet engine on cold startup. After a few weeks I decided to buy an Original AC Delco, and it turns out it does the same. (so, I got a spare )

Pete

I have an old diesel pickup,. its particularly annoying when the temps are minus F-F-F-F- ing cold,.

putting the poor motor onto high idle it takes a good while to get the fan to disengage,. keeping the temps down even after 5 mins or more,..

Put in a nice stereo and you won't hear the fan. But seriously, thanks for the mechanical fan lessons. Nice.

You can hear your fan clutch?

Sounds like it's time to upgrade your exhaust.

Hmmmmmmm

So I need to replace the exhaust and stereo then.

It may not be 5 minutes to go away, but it stays on longer than I would like. As soon as the car warms up a little the noise goes away.

I dont really want to replace the fan assembly at all. I would rather replace it with an electric fan.

......but the stereo and exhaust are first.

BTW, I have now been spreading my new found knowledge on "fan clutch silicone oil".

On a side note....I have always wanted to purchase silicone for my wife. I dont think she ever thought it would be inside of a car!

Where in AZ do you live? I just moved from Gilbert a few months ago.

Bobloblaw wrote:

On a side note....I have always wanted to purchase silicone for my wife. I dont think she ever thought it would be inside of a car!

You might want to get her the newer updated hub(s) they are filled with saline solution,.much safer,.

You could always replace the mechanical fan with the electric fans from a 93 FW. I just completed the swap, and the engine temp is a lot more stable. I did a little write-up on ISSF in the "What did you do to your wagon this week" with a picture. They make the engine compartment nice to look at. You can see front of the engine, and the serpentine belt will be much easier to replace. It frees up about 5 HP as well, and with an LO3, you need every one you can get.

The FW fans are extremely quiet, and I can hardly hear them running.

The whole unit bolts right up to the core support like it was made for it (the FW has the same core support). The wiring requires a little ability, but is easy, and cheap. I used an adjustable temp sender from Jegs to allow the left fan to shut off at 195 degrees. That way it does not turn on, and stay on until you shut the car off. I think it turns on at 210 degrees (standard 15 degree spread). To adjust it, I got the engine up to working temp with the thermostat open, and turned the knob until the fan turned on, then turned it the opposite way until it shut off...done.

I did the wiring a little bit at a time, over 3 days. By not installing the fans until the wiring was complete, I was able to drive the car during the wiring installation. Once the wiring was in place, it only took about a half hour to install the fans, make the final hookup to the red distribution box (battery + side), and adjust the temp sender.

If you are running a little rich, clean the ground at the thermostat housing, including the stud and threaded hole in the manifold. The ground is for the O2 sensor, and computer.

sswagon

I live in good ol' Queen Creek....adjacent surrounding area....

nice mod, Fred. I tried to open the tumbnail on the ISSF, but it refused. Could you send me some pictures of the mod? Hold that, got it working again.
Pete

Fred Kiehl wrote:

You could always replace the mechanical fan with the electric fans from a 93 FW. I just completed the swap, and the engine temp is a lot more stable. I did a little write-up on ISSF in the "What did you do to your wagon this week" with a picture.

Why didn't you post here on the "wagon" forum?

phantom 309 wrote:

Fred Kiehl wrote:

You could always replace the mechanical fan with the electric fans from a 93 FW. I just completed the swap, and the engine temp is a lot more stable. I did a little write-up on ISSF in the "What did you do to your wagon this week" with a picture.

Why didn't you post here on the "wagon" forum?

My pics don't like to post here.

Here's a link to Fred's post.

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Is there a significant difference between Fleetwood fans, stock Buick electric fans, and the Caprice 9C1 electric fans?

I'm not a fan of mechanical fans and would love to do this someday, but would like to make sure I still have lots of cooling power for towing.

The FW fans are for use with an LO5 in the 93 FW. The FW fans are slightly smaller in diameter, but have broader blades. They mount differently, using an upper and lower bracket with 4 contact points for each fan. The 94-96 Buick and 94-96 9C1 electric fans are the same, but different from the 93 FW fans. If you are removing the mechanical fan from a 94-96, just put the left fan with the wiring harness in, and have the car programmed to turn it on, or grab the computer from the car you get the fan from, if it is an LT1 (as opposed to an L99, although the L99 computer will work with the LT1).

The 93 FW fans keep the temperature within specs on my modified LO5. I am making about the same HP as the stock LT1. My right fan runs any time the AC is on, and the left one seldom comes on at this point. Next summer will be the real test.

My mechanical fan does similar.
When it's cold, the fan stays locked up for a few minutes. Depends on how hard I am driving it. If I take off and really give it some throttle, it disengages pretty quick. Normal driving, it's probably less than 5 minutes. I've never had it overheat, so I'll keep the thing hooked up

autoarcheologist wrote:

Is there a significant difference between Fleetwood fans, stock Buick electric fans, and the Caprice 9C1 electric fans?

Some of the 9C1's have a higher powered secondary fan motor for more cooling capacity. I say some because I got a whole rad from a 95 police Caprice with two standard fans, so it's definitely not a given. If you look around you can find one fairly easily, and it drops right in. The motor is noticeably larger than the standard one so it should be pretty obvious. I didn't measure it, but it may even have a slightly larger fan.

I did the electric fan swap and so far I really like it. Quieter and it makes working on the motor much easier.

More than just the 9C1s. There were two upgrades over the standard cooling equipment: V03 (Extra Capacity Cooling), and V08 (Heavy Duty Cooling). V03 upgraded the secondary electric fan motor to 240 watt. V08 replaced the 150 watt primary fan with a mechanical fan and used the upgraded 240 watt secondary.

There are two designs of 240 watt secondary motor. One (ACDelco 158429) is round with a separate electrical connector, so it is easily identified as the more powerful motor. However the other design (ACDelco 158562) is the same shape as the 150 watt secondary (ACDelco 158490) and the primary (ACDelco 158498) motors -- with one flat edge and an integrated connector. You have to look at the part number to tell the 3 motors apart visually.

Buickwagon - thanks for the clarification and part numbers. The secondary fan I ended up using is definitely physically larger than the standard one, both in fan and motor size. I'll have to take apart the other one I got and see if I can find the part numbers on that one to see what they are before I toss them!

The 93 FW has two different secondary fans as well One is 150 Watt, and the other is a 240 Watt. I did not look to see which one I have.