Defroster

Is it even worth it?

Wondering it I should hook it up or let it be...
How effective is it in all reality?

 

Stock defroster?

 

It's slightly effective and very easy to hook up. So I guess it's worth a few minutes of effort.

 

Stock ducting and windshield...
aftermarket motor unit... plumbed it the other day and I was a little more than dissatisfied...

going to try and shorten the hose and see what happens

 

Mine is still intact, kinda. Hoses are kinda flat, etc. But if it's winter I don't drive it anyhow.. Mine works if neeed.

 

I try to make my oem working for the defrost on my 75's but never been able to get a good flow. I bought the summit racing vintage heater 506101 to replace on the jeep.

http://www.summitracing.com/int/parts/vta-506101/overview/


With this one i gain some flow and lot a heat in it but it still not enought at my taste. I was rinding it this winter in tmp around 20 to -30 f and it's got hard to get over the froozen in the windsheild.


I bought for my cousin the summit 991102-1 for his buggy. He wont use it so maybe i will switch the unit because it got a better flow for what i seen.


http://www.summitracing.com/int/parts/sum-991102-1/overview/


But i think the biggest problem for the defroster is the windsheild frame. Air can go anywhere in the frame and the opening is too large so you're loosing pressure and air flow.

 

that's really my big question..
with the crappy spot welds and the fact the whole windshield frame needs to be pressurized the volume of air coming from the little 2" duct needs to be way more than my math skills allow me to compute..

 

Personally I think any amount of time & money spent ( and I have spent a bunch looking and fulling around with different systems) to seal up the windshield frame with silicon or foam and there is room to get in there on most , including getting the large gasket to seal properly to the cowl is energy & $$$$ well spent...........of course a better motor with a higher cfm rating should also be part of the package....................nothing worst than driving that Jeep on a cold morning and not being able to see out of the windshield!

I know you added an aftermarket..... Vintage type AC / heat system which I think is great!.............what is the CFM of that system?

I used part of the Summit #991102-1 to come up with this , but no AC like yours ..........but pretty good CFM in a small package , but in it's current form without re-directing air / heat to where you want it is just a heated box..........of course packaging any heater under the dash of any early CJ is a PITA..........I have almost gotten to the point that perhaps changing the firewall to match a nice OEM compact heater system may be the next trick...........

I would work on getting all that stuff sealed up.............and then maybe see if there is a better motor or cage that will increase the CFM in your unit.

By the way , Nice Job on your project !

 

umm, thats kind of amazing.

 

thanks..
should have some decent updates on the progress shortly.. in the middle of nitty gritty right now..

so that's a vote for at least plumbing the system and hoping for the best...
I agree about the windshield frame.. if I were to take the time and seal off air leaks etc it would add a great deal of efficiency

 

Somewhere a person described the stock defroster alike to having a mouse breathing heavily on the windshield.
Beats what I had in my MB.

 

I believe defroster is required equipment for any vehicle operated on US highway. Although "enforcement" is likely not an issue ;p

 

Inadequate heat & defrost was the general consensus with these CJ5s no matter what any of my friends that had'm growing up tried to do. Back then I had a 1964 VW Bug with the same anemic heat and airflow problem. We were relegated to using a small 12v defroster that plugged into a cigarette lighter.......which I believe I bought it back then through JC Whitney. It worked OK for just the drivers side hanging from the visor or dashboard....and I had to make sure I didn't fully discharge my 6 volt battery while using it! I think I had seen some more modern versions available recently. Use to have a ice scraper hanging with a leather lanyard from the bug's rear view mirror so I could scrape the frost off the inside...................................Ha!

 

Yep, did the trip up the highway in 3rd gear in my '64 VW many times to try to keep some of the windshield somewhat clear. usually only a 3x3" patch in the corner depending on the weather. One ice storm the side window was down and I had my head out so I could get home.
Both Jeeps have defrosters, both Jeeps have scrapers and squeeges in there too. Always fun to be scraping the ice off the inside of the windshield while driving.

 

I think I said an "anemic" mouse.

This is why all the old plow jeeps you see always had a fan mounted on the steering column.

My old willys pick-up I used to drive with the window open, so I could blow my breath outside, keep the frost from off the inside glass.

 

Thanks for the correction. I've talked a few old guys that drove snow plows for the state. At some point they would just have to roll the windows down and hope they had enough clothing on. When the temps dropped low enough, there was no other way to deal with the condensation in the cab.

 

Back in the day when Four Wheeler had the readers tips in the back of the magazine, they showed one old flattie where the owner plumbed his defroster into the roll cage's cross bar, which had bungs welded at regular intervals pointing toward the windshield. Don't know if that would contribute to rust inside the crossbar, but from their description it seemed to work well. I believe Patrick's (from this board) dad has a similar setup, but instead of using the roll bar, he ran some PVC along the base of the windshield, and had openings cut out to accept the defroster diffusers that would have gone on the windshield. It's been a while, but I think he ran it behind the roll cage's cross bar, so you had to look close to see it.

 

Another old trick for rally drivers and such was to mount a piece of clear acrylic 'glass' over the defroster output, on the drivers side of the vent, close to and parallel with the w/s glass.

This created a narrow channel to concentrate the hot air, making a warm space between tne two surfaces, and forcing the air higher up the w/s.

 

Recently bought an old $500 98 Accord. It came with anemic cows breath AC, a leaky rear window, and (at first I wondered why) a Cosctco size of Rain-X interior. First time I drove it in cold rainy weather the glass fogged badly...i caulked the rear window to stop leak, dropped the heater fan ( screws) and discovered a huge (old) rats nest inside the squirrel cage. No wonder the defrogger didnt work-the fan barely spun, and when it did, made noise, and barely blew a gnats fart of air. Once the fan was cleaned and bushings lubed, it blew real good. Added freon, and the AC suddenly worked great. Moral of the story-make sure your fan is clean and lubed. And perhaps run heater ducting only to drivers side windshield. I like the idea of added inline fan shown above, also...