Community Forums

kernst52 · 06-29-2022, 12:44 PM

I have a 2007 Fleetwood Terra with a W22 and an 8.1 motor. In the summer I get a rattley noise from the area of the engine when climbing hills and it goes away as I drive downhill on the other side - only when the weather is hot. Does anybody know if that would be the fan clutch? Thanks.

Ken

Skip426 · 06-29-2022, 12:48 PM

The thermal hub, fan noise is a common complaint on 8.1l engines and your description of ; when it's heard ; is classis.

Flyer15015 · 06-29-2022, 01:01 PM

Rattily noise might bear some investigation.
Mine sounds like a turbine, smooth and loud.
You can mitigate the fan coming on, if you rewire the 2 pancake fans up front on a toggle switch, and turn them on when in heavy traffic or climbing hills in hot weather.
I used a 3 way toggle. Up is fans on, center is off, and down is the OEM circuit.
I still get to hear the turbine on long mountain pulls, but not quite so often.
Not a difficult thing to do.

Mike in Colorado

donr103 · 06-29-2022, 04:43 PM

Rattle sounds are bad.. you should hear a roar .. you need as stated above.. have investigated.. could be broken fan.. or fan clutch.. or idler .. you bad belt.. get it checked out asap..
Good luck and keep us posted

TandW · 06-29-2022, 04:53 PM

Late timing/bad crankshaft position sensor= engine knock which is prone to occurring under load and can sound like a can of marbles or a rattle. Poor non-top tier fuel of low octane can bring it on.

Isaac-1 · 06-29-2022, 08:22 PM

Also check the fan blades on the main fan behind the radiator, they were plastic on the W series coach and prone to age cracking.

Dsrtrider · 06-29-2022, 08:49 PM

Rattle noise is usually not fan clutch more likely tensioner or idler pulley

kernst52 · 07-09-2022, 04:44 PM

Thanks for the replies. I loosened the belt and checked the tensioner and idler pulleys and they are both OK. I think I will wait until our next trip this summer and listen to the noise again.

Ken

Arch Hoagland · 07-09-2022, 08:20 PM

I've replaced two idler pulleys....common failure on the 8.1.

Telephonebil · 07-18-2022, 11:02 PM

sorry for the interruption, but i cant find how to post a question. I too have a fan noise.
I think its the oil cooler fan assembly. the fan is wobbling. its the fan right out in front when you drop the hood. It seems to come on when the AC is on.When it wobbles it hits the cooling fins behind it. I need to find one. Any ideas as to part number ?? 2002 Sunova 8.1 chev thanks in advance.

1972VWbus · 07-19-2022, 01:39 PM

Confirm that your timing is correct. The rattling could be pinging = excessive timing.

mfire1339 · 07-19-2022, 01:54 PM

Get underneath and look at bottom of the fan shroud. The fan is real close. Mine has a couple extra screws to hold it away from fan.

AKIQPilot · 07-19-2022, 02:49 PM

Quote:

Originally Posted by Telephonebil

sorry for the interruption, but i cant find how to post a question. I too have a fan noise.
I think its the oil cooler fan assembly. the fan is wobbling. its the fan right out in front when you drop the hood. It seems to come on when the AC is on.When it wobbles it hits the cooling fins behind it. I need to find one. Any ideas as to part number ?? 2002 Sunova 8.1 chev thanks in advance.

Here is a link to the factory original fan. You may be able to find this fan or one similar for less but this is the factory fan. The guys at URVP are awesome. They can get you hooked up with the exact part you need.

https://www.ultrarvproducts.com/W800...ic-A-c-Fan-Asm

LETMGROW · 07-19-2022, 02:54 PM

This sounds suspiciously like detonation. If you are running regular gas now, try running your tank low on gas and fill up with premium gas. You may need to boost octane a bit to make up for carbon deposits on the tops of the pistons or in the combustion chambers.
If the noise lessens or goes away you'll know what is causing it.
What temperature are you running on the temperature gauge? Is your "Check Engine" or "Service Engine Soon" light coming on when you are driving?
A lean mixture can also cause detonation. A common problem on 8.1 engines in Motor Homes is a bad or dirty MAF (Mass Air Flow) sensor. These can often be cleaned by removing the sensor and using MAF sensor cleaner to clean it following the directions on the can. Do NOT use anything else. These sensors are delicate. Do NOT try to blow out the sensor or dry it with compressed air. The sensor will be permanently damaged if you do. Yes, air flows past the sensor but not at 125# plus pressure.