How Important Is Foam Tape For Radiator Face? (1 Viewer)

[turbocruiser]

Fine folks, I'd like to learn your thoughts on this please, when I replaced my radiator with the Ron Davis Racing variant I never put foam tape for the front face of the radiator on. With the rear face of the radiator the fan shroud sits super tight up against almost all of the radiator so I'm not really worried at all about that area in general, but, for the front face there is a good 1/2" opening that would theoretically allow air swirling all around the engine bay to get into the radiator. On the one hand that would seem to reduce the cooling capacity but on the other hand there are simply sooo many openings from the front cross-clip of the body that I cannot see how sealing the radiator to that one edge would possibly prevent all that air in the engine bay from flowing through the backside of the headlights and all the openings all around that front cross-clip anyway IF the air was so inclined ( I think that it was well established that the hotter high pressure zones whether moving or at stand still were towards the back of the engine bay).

To add some additional info to my question, when I received the radiator I noticed right away that there was no foam tape for it in the box and I called to RDR to ask them about that. One of their technicians told me that they try to avoid installing it cause the tape just eventually disintigrates, it is hard to really seal just to the outside air, and the capacity of the radiator is much more than enough to effectively deal with whatever small increase in air temps are towards the front of any engine bay. I asked if that applied when wheeling where speeds are slow at tops and he told me yes, less so than at top speed of course, but still so enough not to worry with the tape there. Made perfect sense so I installed without it. Its not that I'm questioning the guidance he gave but I'd just like to learn the thoughts of people who are much more familiar with our rigs in particular. I'm sure some of you have had your foam from your radiators let loose at some point and did you notice a measurable increase in temps, OR, after adding the foam tape back did you notice a measurable decrease in temps? Also, I've asked LX_TREME about his air diverter panel which should help some with preventing the air in the engine bay from flowing over the radiator support and into the radiator and SHOULD also help some with force feeding more air through the radiator instead of through all those openings all over the cross-clip. Anyways, thanks so much as always for your thoughts.

 

[Tools R Us]

... With the rear face of the radiator the fan shroud sits super tight up against almost all of the radiator so I'm not really worried at all about that area in general, but, for the front face there is a good 1/2" opening that would theoretically allow air swirling all around the engine bay to get into the radiator. On the one hand that would seem to reduce the cooling capacity but on the other hand there are simply sooo many openings from the front cross-clip of the body that I cannot see how sealing the radiator to that one edge would possibly prevent all that air in the engine bay from flowing through the backside of the headlights and all the openings all around that front cross-clip anyway ...

Have never done a test on the 80 series, but on the 22R mini sealing the radiator to the core support was good for a 4F drop in A/C vent temp when idling at 100F+. It's a pressure difference/distance thing, fan output causes a slight pressure increase, the intake side of the coolers have a slight suction, both effects dissipate in a relatively short distance. If the front side of the radiator is exposed to under hood pressure a significant amount of heated air will be recirculated. The radiator foam, hood, hood to core support seal, lower airflow pan, etc are all designed to control the air flow, reduce recirculation.

Like most things core support holes are a compromise, sealing them all may help at idle and hurt at speed. The headlight, corner marker, etc, holes work as air bleeds at speed, allowing cooler airflow where needed. On the rigs that I have checked, this is especially true in the passengers side, the airflow along that fender well is the coolest under the hood. My guess is it's on purpose to cool the air intake, injector resister, etc.

Is the foam critical for truck operation, in most climates probably not. But any fan is only capable of moving X amount of air and you provide the energy $$ to make it work. By better controlling the airflow, more of it is doing the job instead of being wasted, making a more efficient system. Your not insinuating that Toyota put those seals there because thay had extra foam they needed to get rid of?

 

[turbocruiser]

Excellent answer, thanks Kevin, any particular type of tape you recommend that tends to last a long time? Thanks again I appreciate it.

 

[Tools R Us]

You want "waterproof" foam, any foam that absorbs water will fall out. The stuff that I use is weather stripping from the hardware store, look for high density, water proof, closed-cell, etc on the package, the "lighter duty stuff will soak up water, become heavy and quickly fall out.

There two "problems" that I have had with it; for most applications the strips are too thin and the adhesive isn't strong enough. For the thick thing I just stick two strips together (it sticks to it's self very well, just doesn't stick to the radiator well). The adhesive thing is mainly an assembly problem, solved by holding it in place and/or using masking tape until it's assembled, then removing the masking tape. It should be pinched in place, if you have a 1/2" gap, use 1"+ of foam, when pinched between the radiator and core support it stays/lasts well.

 

[turbocruiser]

Ahh thanks again excellent answers, I remember that I took a little look at the hardware store when I was first installing the rad but I encountered exactly what you wrote - I needed to put two pieces together to get "squish" with what was available at the store. I thought that was a recipe for one of them separating and getting wildly wrapped around the fan clutch so I said "no thanks." I also looked at McMaster Carr and did not see something specific that would work. I then looked here and saw these.

HST Materials Company 10 ft., A=11/16" x B=5/8", Stick On Replacement Sponge Rubber Weatherstripping, Style 3 : JC Whitney: SUV Parts & Accessories


HST Materials Company 10 ft., A=3/8" x B=5/8", Stick On Replacement Sponge Rubber Weatherstripping, Style 4 - 10ft : JC Whitney: SUV Parts & Accessories

I was thinking that even if the adhesive was somewhat weak I could use rubber cement on the rad and on the tape for a really permanent placement?

Again, all this searching for something other than the tape was basically because I thought that two of them stuck together would peel and cause a potential problem with the fan clutch. If that isn't the case maybe I should just drive down the street and get the tape from HD? Looking at this rubber tape and knowing how yours has held up, what would you recommend? Thanks again for the advice. This is next on the to do list and with my temp gauge I can measure any measurable difference of 1 degree or more. I'll post up with differences before and after.

 

[Tools R Us]

... - I needed to put two pieces together to get "squish" with what was available at the store. I thought that was a recipe for one of them separating and getting wildly wrapped around the fan clutch so I said "no thanks." ...

In my experience it sticks very well to it's self, in fact if you need to reposition it, most of the time the foam rips before the adhesive comes apart. But finding some the correct size would be cleaner, you may also try a local paint/body shop supply store, good ones carry a large selection of foam seals.

... I was thinking that even if the adhesive was somewhat weak I could use rubber cement on the rad and on the tape for a really permanent placement?

A tech buddy uses contact cement type spray adhesive with good success. For me it's messy, too much work, by the time he done screwing with that stuff, I'm long done and on my second cold beverage!

 

[tblume]

try this;

find a roll of tape backed foam, closed cell, cloth reinforced for truck rails under a canopy. the stuff I found was something like a $ a foot, its pretty tuff under my canopy on the taco, has held up to many years and multiple on/off's of the canopy. it's 2" wide, but a careful knife and you have 2-1" pieces.

clean the radiator where the sticky goes with rubbing alcohol, or plastic safe aerosol like for throttle body's or MAF sensors, and stick away, what can it hurt, and if you think it helps; it probably will.

 

[alvarorb]

Forund this on Amazon High Density Foam Tape Waterproof Sealing Strip CR Strips Neoprene Single-Sided Adhesive EVA Seal 1/2in X 1/2in X 13Ft
What do you think?

 

[LandCruiser65]

Forund this on Amazon High Density Foam Tape Waterproof Sealing Strip CR Strips Neoprene Single-Sided Adhesive EVA Seal 1/2in X 1/2in X 13Ft
What do you think?

this thread is 16 years old.... buy it and try it out.

 

[alvarorb]

this thread is 16 years old.... buy it and try it out.

I did!

 

[LandCruiser65]

I did!

ok.... now install it and see how it holds up....