Engine/Transmission (1994 - 1998) Question about Fan Shroud

[krs]

Hi,

I'm in the middle of something that requires removing the fan shroud and doing that I've found two panels on the front to the sides that are rivetted onto the shroud. They face the radiator, are real close to the back of it and seem to block about 25 - 30% of the air that could go through the radiator.

There's nothing in the manual about them. The shroud fits around the fan fine and directs the air through the radiator but these panels are like having winter gaurds on all the time. Is this normal and why?



Seems like the more radiator surface exposed to airflow the better, but these things stand in the way. I'm wondering if I need the fan shroud at all except to keep me from falling in.

 

[Joseph Donnelly]

DC wants all the air flow to be pulled by the fan when needed.

 

[DMC]

Never heard of this. Could it be you bought the truck used? If so someone might have rivited those in there to help with temp fluctuations. Might not be a bad idea.



Don

 

[krs]

"DC wants all the air flow to be pulled by the fan when needed. "



Yeah, but why block such a large part of the radiator? There is ducting built into the shroud that looks designed to flow air that has come from the outer portion of the radiator to the fan and it's those ducts that are blocked by this. I did buy the truck used but this looks OEM by the expanding type of plastic rivets used. Could be a way of forcing the engine to a warmer temperature for emission reductions? The truck is a '98 manual originally sold in Boise. Our '97 auto has the same thing and was also bought new in Idaho. I guess they're a normal thing but wonder if they might be a colder weather smog thing. Trying to be clear about where the panels are: These panels block the ducting that's where the coolant and washer bottles mount and is in front of both bottles. The bottle mounts form the back of the duct I'm talking about.



I'm suspicious about them because it seems like they'd cause heating up while pulling hard like over mountains in the summer and because I don't see why they weren't molded as part of the shroud when it was made instead of being a put on later part. I'll take them out if they could harm the motor in any way. Just seems weird to have a big radiator and then block a big part of it off.



Sorry for this wordiness but I'm trying to be sure that people know what I'm asking about.

 

[schmerster]

I just came across the same thing and did a search here to find info on the panels. I am going to run without a fan, and will remove these panels as well to see how well it cools. The only reason I'm re-installing the shroud at all is so I can have something to hang the bottles on.



What did you find? Any difference in cooling performance?

 

[DLausche]

I am interested as well about these covers that are attached to the fan shroud. Defenitely looks like an after though of some sort on DC's part. The fan shroud looks like it was designed to flow the air well, albeit not via the fan, if these blocks were not there. I think I will leave them be as-is for the winter, but try taking them out in the spring to see what difference it might make when towing the TT.

-Deon

 

[Berrigan]

Ive heard people say that removing them will increase air flow. The way I see it and as made by DC those panels force all air through the rad. If removed and at idle not moving some air will get sucked in from the engine compartment. I think at low speeds or at idle removing them will decrease rad heat rejection. But at higher speed with (ram air) it could do the oposite. I think there just filler material to deal with the fact that the rad is so wide and a round fan pulling from the center needs to be ducted to the entire surface area of the rad to move air thru it all at zero road speed.



I too have pondered removing them but woundered what the head pressure at the condenser would do with less air flow at idle. If anyone takes them out please post the results. Bill

 

[drawson]

I took my panels off when I was running electric fans, even though I went back to the factory fan I have left them out with no problems. The idea is that when the fan clutch kicks in all of the radiator has air draw through the center. The fan clutch runs so little of the time on my truck, the only time I think that the panels might be helpful is doing some really low speed crawling with the A/C on.

 

[Berrigan]

Drawson,

Did you notice any cooler temps when towing with the panels out? Bill

 

[drawson]

I have never had a radiator temp problem. I didn't notice a increase or decrease in rad temps. But even at my high HP levels it has never been an issue

 

[Gary - K7GLD]

For some reason the old "IF it ain't broke, don't fix it" comes to mind...