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Do your defrosters really work?

AUSMHLY

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I think I remember reading a post about someone asking about why their defrosters are not defrosting...imagine that with our Healey's.

So I thought to myself, hey here's another opportunity for me to take my car apart...again! I wonder if mine works. What was I thinking. Have you not learned by now grasshopper that what you ask, you already know the answer.

Well the drivers side had just enough air to sort of move a single sheet of tissue paper. Passenger side, forgetaboutit.

I bet the hose came off. What was I thinking this would be a quick fix. Ya know those computer speakers, cup holder, led lights I added. Yup, gotta remove all that stuff to get to the heater box, so the heater box can be removed to get access to the air hoses. Oh boy, another project.

The short version:
Got the box out, hoses were on.
Before replacing the box, I made a foam seal to go around the back of the box opening that lines up to the heater box channel. No air will escape here now.
Installed everything.
I removed the top dash and made a foam seal to go around the defroster finisher, so that the air will not leak anywhere under the wood dash top.

Put it all back together, closed the heater box channel flaps, turned on the blower and wah-la! No improvement at all. Still the same. What!?

Those who installed theirs. How did you have the two hoses lined up. Both of mine plug into the round holes and go the the left of the box, looking at the back of the box, as shown in my photo. I have the passenger hose going into the hole that is in the corner. I don't know if the passenger hose ends up on top of the driver's hose and maybe, just maybe it gets flattend abit. Just throwing my trouble shooting ideas out.

So, what's up with the lack of air pressure. OK, guys, tell me that this is normal for our Healey's.
Well except for Greg will reply that he could blow dry his hair from the force of the air, I mean wind that shoots up the dash vent and bounces off the windscreen. And let's not forget Lin, with his Cape International two speed heater radiator. 1. Fan on, 2. Fan way on.

Cheers,
Roger
 
I knew you were up to something. You were too quiet for a couple days. The only thing I think is different is how I understand your hose routing. Mine don't crossover each other. Here's a photo. Have you removed the hose from the motor to see it the fan is at least blowing air <span style="font-style: italic">to</span> the heater box? I have a vague recollection that the hamster wheel has a grub screw that tightens to the motor shaft.
 
Well, Roger, yours is much prettier than Greg's even if it doesn't work any better. How about installing one of those accessory fans (usually battery operated but you could figure out a way to convert to 12 volt DC with an additional relay and certainly with an in-line fuse) right over the top of the cup holder, so that it will strategically blow the heat from the starbucks coffee in the cup holder onto the windscreen. Come on,I know you are up to it!

Lin
 
Greg,
Well, now that is pretty cool, er I mean hot!
Looks good. At what stage are you on your reassembly? How about some photos?

Lin
 
Lin said:
Greg,
Well, now that is pretty cool, er I mean hot!
Looks good. At what stage are you on your reassembly? How about some photos?

Lin

Hey hey Mister Lin, let's not go there, asking what stage greg is on his reassembley. This post is all about me, and don't you forget it!

Alright, I'll give a little and play well with others.
Insulating a heater box. How can I possibly keep up with guys like you two.

My fan, she works just fine. I have plenty of air coming out the box when the flaps are open. Greg, do you have yours up and running? Do you get the same amount of air from both vents? And being you lined your box with heat refective foil, I'm sure you put a hot dog on a stick and place it over the defroster vents. OK, this dogs defrosted, and one more minute... yup, she's cooked! Who's got the mustard.
 
AUSMHLY said:
Greg, do you have yours up and running? Do you get the same amount of air from both vents?
No, I haven't run mine yet.

AUSMHLY said:
And being you lined your box with heat refective foil, I'm sure you put a hot dog on a stick and place it over the defroster vents.
My main thought for the lining was to keep the heat out of the cockpit when I didn't want it there.

AUSMHLY said:
My fan, she works just fine. I have plenty of air coming out the box when the flaps are open.
I wonder if you have an air leak somewhere in the main square tube? Big enough to rob the demisters of pressure (since they are small openings) but not big enough to completely stop flow to the underdash flaps.

AUSMHLY said:
Who's got the mustard.
You mean to tell me you don't have Grey Poupon in the glovebox? :rolleyes:
 
Lin said:
At what stage are you on your reassembly? How about some photos?
Nothing really new to report. Work on the car has been really slow for various reasons. I took a couple weeks off from it to make a guitar (started as a plank of wood). Playing helps for a surgery I had on my hand 2 years ago. Just finished it yesterday for evaluation. I'm trying to decide if I need to take more material off the neck.

Feel free to post a bunch about the guitar in this thread and don't mind that Roger guy.
happy0193.gif
 
HI Roger,

I have a suggestion for your consideration. I think the original fan motor is inherently too weak and doesn't blow enough air. 20 years ago I had a dead Datsun 240z out back and noticed the heater fan is mounted in the same relative location as our Healeys, on the inner right fenderwell. The only difference is that it is build for square ducting instead of round. By making a short square-to-round adaptor, it bolted right in (if I remeber right the mounting holes even lined up)and is angled the same so the ducting hooks up at the same angle. This fan blows a lot more air and has been doing a great job at defrosting the windsheild for the last 20 years. The only problem is that is seems to draw more amperage and in a fairly short time it melted the stock heater switch so I just mounted a heavier duty toggle switch. Some of you electrical wizzards will no doubt have a 'relay' in mind that could allow the stock switch to be used...

I figured that since we have all heard for years about how they 'copied' Healeys to engineer the 240Z, it was poetic justice to rob parts off of one of the copies and use it to my advantage, not to mention I'm cheap and substituting a free part is often more attractive then spending money on a 'correct' part.

Dave Phillips
 
Is the deverter working properly on the pull-push control? Just a thought. Mine does not seem to blow much but when needed it gives me a 4 inch window (if you scootch down to wheel level).
 
tahoe healey said:
Is the deverter working properly on the pull-push control? Just a thought. Mine does not seem to blow much but when needed it gives me a 4 inch window (if you scootch down to wheel level).

Hey TH,
Thanks for jumping in. Yes it does and thank you for bring that up. After installing the heater, and the connecting cable, I looked inside the tube opening and watched the flap as I tweaked the connection. I found it's easy to go past dead open when you think you have it. Then I slid the air tube on. Some things I know work properly. My guess is still with the small air tube going to the demister being flattened. Bummer is I can not see that area when everything is buttoned up. Oh I've tried with a small mirror and flashlight. You betcha

I guess I should be thankful that what ever amount I have, is on the drivers side. I don't plan on driving my car in the rain, snow, any condition that may mess up my hair. It's all about the dew.

This project is a tweaking project. I don't plan on using the demisters, but should I ever need them, I'd like to know that down the line I won't be saying..%#&@# when I find they don't work. No surprises please. I don't even know how well they (the drivers side) works or not in the conditions that require it. I guess I should get my better half in the car and put some Barry White music on and start whispering sweet nothings in her ear. Honey, is it hot in here, or is it you! Your steaming up the windows. Hold that thought while I check out the Healey demister. I know, I'm such a catch with sweet talk like that.
 
AUSMHLY said:
Honey, is it hot in here, or is it you!
Roger, you ain't listnin to Barry! Don't make it a question. There should never be doubt in your voice that she is the hotness. Just tryin' to keep you from sleepin' onna couch buddy.
 
Lurker reporting in. You guys are hilarious. Really nice guitar Greg.

Despite the obvious entertainment value, I read these threads because some day I may find a fraction of the energy you guys pour into your cars, and this subject will be on the short list. I drive my BJ8 both top up and top down in cooler weather, so I want the defogger to work in order to see and also to occassionally get a bit of warmer air above my waist. The only time I ever felt any air at all was driving into a 10 degree F blast of wind.

Right now the ever-present rag (kept out of sight behind the driver seat) gets windshield duty too often. And for me, without any of the confirming homework, it is all about the pathetic fan. I was interested to note that Roger thought he actually had decent air flow going into his box. If so, I am encouraged. But it has to go SOMEWHERE then. An earlier thread mentioned closing floor vents to deflect more above. I am not sure I see how to do this, since I detect very little air flow anywhere at all. When you guys solve this one, spell it out for the mentally challenged out here.
 
When I first purchased my BJ8 about 5 years ago, I could get no air through the heater or defroster with or without the blower on. Further investigation found that some enterprising squirrel had deposited 13 pine cones in the cold air to blower hose. Absolutely a true story.
 
Hello all,

It seems because of the hack on this system yesterday, the post I entered was deleted. Thank you Basil for backing up every night. There are bad guys out there and there are good guys like you keeping them at bay.

I appreciate all the help, advise and thoughts from everyone who takes the time to contribute to our posts.
Yesterdays post got deleted, this one tells of my findings.

It seems the reason some of us may not have any air pressure coming out of our demisters could be caused by the following:

Something in the air hoses blocking the air path. (13 pine cones)
The air hoses have an opening in them. (Puncture, rip)
One or both of the small hoses above the heater may be crushed.
The blower is not working.
The air flap in the heater is not fully open.
The rubber elbows on either the heater or the bottom of the dash has come off.
Something is logged, clogging the air demister vents on top of the dash.
The seal between the scuttle and the frame is not there or missing in some areas.
The two flaps on the heater box rail are open. (close these and the pressure will increase to the demister tubes)

What was, is, the problem with my car? The PO either did not or did not do an adequate job of sealing the area around the two demisters between the shuttle and the frame. When the air reaches the bottom of the dash thought the two rubber elbows, instead of it filling up a small sealed area meant for the demisters, it leaks out into the entire space between the shuttle and the frame.
I'm not sure how I can fix that without taking the two pieces apart. That's too big a project for this let's see what it would take to fix project. Here are two photos that show the air passage. The cardboard should not be able to slide between this area.

So if you don't have the air pressure needed to demist your windscreen, one of the items I've mentioned may solve your situation.

Cheers,
Roger
 
Re: Crazy McGuyver time.

Greg,

Thank you Greg for taking the time to create those drawings. I really do appreciate the creative people here that jump in and offer solutions with my and their thinking outside the box stuff.

I like the way you think. Over the past two days, I have been visiting the hardware store trying various soft clear plastic tubes. 1", 3/4" and 1/2" sizes. And plastic funnels.

Trying to push the tube into that area is one of the problems. Through the hole, make a sharp bend, push into the cavity which becomes thinner as it reaches the end. (Going away from the mirror.)

If I can get the tube up in there, I will try slots and holes in the top of the tube. If the slot is too long, the tube will open up too much. Where as the holes may not let enough air out if there is not enough air pressure. I also need to figure out how to seal both ends of the tube.

Once the tube is in, cut a hole in the bottom of the tube, and insert another tube straight down into the rubber elbow as the passage way. Bottom of the tube diameter hole I can make the same as the passage tube for a tight fit. I may have to put a funnel, (plastic is all I can find) on that end to match the inside diameter of the rubber elbow, which is oblong. Or pass the tube through the elbow and install the funnel at the junction where the Healey paper tube meets the elbow, which is round.

That's what I have been "playing" with. I like your idea of how to widen the end of the tube. Also the pulling up and glue it. The glue it part would certainly be a challenge. Getting the glue to stay put, the hose to say up against the top. All working thought that small slot, top and bottom. I may have to fly you up for that part of the job.

My first hurdle is finding the right tube. Too hard and I can't get it up in there. Two soft and it may flatten out from hot days.

I've already tied cutting the tube in half and pushing it in, thinking the bottom of the tube will push the two edges up against the top of the dash and make a u-tube.

This may be the first project that I may have to let go.

Here's a question for you engineer guys.
The Healey's heater tube is larger (ID 2 1/2") than the tube I will be sandwiching in the dash (1,3/4 or 1/2"). Will there be the same amount of air coming out of the now smaller tube? Will the air pressure increase out of the smaller tube? Example, more pressure, but less air?

Feel free to respond with flow charts, pie charts, Lotus spread sheets, technical diagrams, scientific terminology, Einstein theories or my favorite, crayon on a napkin showing a circle with an arrow going though it...the air goes in here and out there.
Roger
 
Re: Crazy McGuyver time.

AUSMHLY said:
This may be the first project that may have to let go.
Honestly, that's probably what I'd do. One thing about getting the hose around that bend. Vinyl hose will soften dramatically with a heatgun, then firm up again as it cools. Vinyl isn't the easiest to glue however.
 
Re: Crazy McGuyver time.

The only thing that comes to mind is putting the smallest tube that you can find attached to a bathtub silicone caulk tube. Try and caulk around the edge of the depression. I hope that you find a solution.

I haven't driven my car in many years but I do recall the bad air flow for the demister. I'm sure that you already realize what you've done for folks like me who haven't yet put their car back together. I am now aware of the problem and can fix it ahead of time. THANKS!!!!!! Your efforts are very much appreciated!!
 
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