My Willys 3A and 3B Community

TECH FAQ SECTIONS => Engine compartment => Topic started by: garage gnome on April 04, 2013, 10:48:34 AM

Title: Harrison heater tips, mods and install
Post by: garage gnome on April 04, 2013, 10:48:34 AM: All this talk about Harrison heaters made me want to post tis up. It might be useful to someone in the future.

[size=16]Restoration tips:[/size]

I don't know how many people actually know this but there should be rubber grommets between the firewall and the heater core tub brace on the back of the heater. The left is an original and the right is what I replaced them with.

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6181.jpg)

What was left of my original decal on my '53.

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6169.jpg)

[size=16]Modifications:[/size]

My heater had a defroster duct port which I wanted to use with an original style defroster duct. But I also wanted it to work more efficiently.

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6177.jpg)

So I made some doors that I can open and close for the other two ports.

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6178.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6174.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6173.jpg)

And after some paint and a custom Willys plaque, it is ready to go!

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6184.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_6185.jpg)

Defroster hose routing. I am not sure of how it would have been routed from the factory, but this way made sense to me.

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_7206.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_7204.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/100_7218.jpg)

[size=16]Installing a Harrison in your original body:[/size]

My '49 never had a heater installed, but I wanted one for the cold months. The rust pile I mentioned earlier has just the right amount of patina and original paint for it. I had also collect enough original parts to install it.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/D7D17A42-6D6A-4A83-B346-0776F631AA46-1174-0000021814719525.jpg)

It still had the three original knockouts for it.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/8f03d4b0.jpg)

On the inside of the firewall, you have to take two cage nuts out. The very top one for the passenger side bracket for the air cleaner and the very bottom on for the drivers side bracket for the air cleaner. I peeled the cage back and beat it flat with a hammer.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/C1B651B8-4E77-4528-9DA9-3D9B621D2710-1174-0000021821592885.jpg)

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/2709A202-6A83-4F08-B67B-7802C5DBE9DD-1174-0000021827FDF4D6.jpg)

And then you get some nice paint samples!

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/E382C302-E0AE-4EBD-B77A-BDA437D1006E-1174-000002185F2FF32D.jpg)

Then you can maneuver the heater into place. I had to cut a 1/2" off the tubes to get it to fit.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/F87CF134-A16A-4415-9D5B-0AEE4C7AAE86-1174-00000218348BD6C5.jpg)

Then under the dash, there should be a hole for the original switch.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/E1968F5B-3CF8-4240-8AE1-EA641FB0559A-1174-00000217EC46E396.jpg)

And then after a little wiring and plumbing, you're all done! On an engine that never had a heater, there should be a pipe plug on the back of the head and another one on the pump. I had to heat mine to get them out.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/508F762E-1005-456B-93F0-D3C051C5E88C-1174-00000218668A2A19.jpg)
Title: Re: Harrison heater tips, mods and install
Post by: johnrb3b on April 05, 2013, 08:29:33 AM: I believe the original setup had a right angle connector on the defroster manifold.
Like this:
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on April 05, 2013, 10:08:00 AM: Thanks John. I saw the bulletin on the defroster on the 3b page. I'd still like to know what the original hose would have been made out of.
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on April 07, 2013, 09:33:12 PM: More on the defroster: http://www.film.queensu.ca/cj3b/Tech/Defroster.html

See pic three: http://www.film.queensu.ca/cj3b/Dating/Dating1.html
Title: Re: Harrison heater tips, mods and install
Post by: maximushuntermus on April 14, 2013, 07:14:42 PM: Any chance you could show us the heater hose routing and connections, would this be appropriate here in the post or should it be somewhere else? Either way I could use some help, Thanks...
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on April 14, 2013, 09:15:29 PM: You need these two fittings picture. The one on the left goes on the head. I can get some better pictures tomorrow.

(http://i748.photobucket.com/albums/xx125/willyscjmj/1949%203A/D7D17A42-6D6A-4A83-B346-0776F631AA46-1174-0000021814719525.jpg)
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on April 17, 2013, 07:36:37 PM: Here is where they connect on the engine.

(http://i748.photobucket.com/albums/xx125/willyscjmj/7F5E571C-23AE-4ECC-B5CF-A70C8682588A-2165-0000049ED2F89864.jpg) (http://s748.photobucket.com/user/willyscjmj/media/7F5E571C-23AE-4ECC-B5CF-A70C8682588A-2165-0000049ED2F89864.jpg.html)

(http://i748.photobucket.com/albums/xx125/willyscjmj/8852F59F-F3C1-4FE8-B46E-E4471EF1259E-2165-0000049ECDE1B9AA.jpg) (http://s748.photobucket.com/user/willyscjmj/media/8852F59F-F3C1-4FE8-B46E-E4471EF1259E-2165-0000049ECDE1B9AA.jpg.html)
Title: Re: Harrison heater tips, mods and install
Post by: Ryan_M on April 17, 2013, 08:05:07 PM: I made the same connection on the head but took a different approach on the water pump.
Title: Re: Harrison heater tips, mods and install
Post by: athawk11 on April 18, 2013, 02:29:06 PM: I wanted to throw in some additional items you may come across if you find a Harrison in your Willysï¿½or plan to add one on.

L-134 engines are interchangeable between many Willys Jeeps. ï¿½Itï¿½s common to NOT have the original 3A engine in your Willys. ï¿½

Early L-134 military heads were not generally set up for heaters. ï¿½You may not find a plug at the back of your engine headï¿½.

(http://i1195.photobucket.com/albums/aa397/athawk11/20130417003e_zpsfb66fcfc.jpg) (http://s1195.photobucket.com/user/athawk11/media/20130417003e_zpsfb66fcfc.jpg.html)

You can drill and tap this to add the correct heater hose attachment, but it would require pulling the header or possibly the engine. Thatï¿½s a lot of work. ï¿½

This was the modification I found on my GPW engine (the Ford version of the L-134) This was a somewhat common approach when adding the Harrison heater to a military head.

(http://i1195.photobucket.com/albums/aa397/athawk11/20120110002.jpg) (http://s1195.photobucket.com/user/athawk11/media/20120110002.jpg.html)

All other connection and installation points are the same as described above. ï¿½Looks like I matched Ryanï¿½s connection at the water pump.

This is another detail you might find on a Harrison installation. This is a heater hose bracket. ï¿½It was mounted to the passenger fenderï¿½

(http://i1195.photobucket.com/albums/aa397/athawk11/20130417001e_zpsb20f5014.jpg) (http://s1195.photobucket.com/user/athawk11/media/20130417001e_zpsb20f5014.jpg.html)
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on April 18, 2013, 05:06:09 PM: Thanks Tim for adding that additional info! I totally forgot about some heads not having that port. I also didn't know about the heater hose clamp on the fender.
Title: Re: Harrison heater tips, mods and install
Post by: maximushuntermus on April 18, 2013, 05:27:35 PM: Thanks guys one question, on the water pump attachment does either side put you in front of or after the thermostat?
Title: Re: Harrison heater tips, mods and install
Post by: maximushuntermus on April 18, 2013, 05:31:18 PM: Ooops I know that answer, duh the thermostat is in the water neck on top. So it doesn't matter so much on the water pump.
Title: Re: Harrison heater tips, mods and install
Post by: Rus Curtis on June 21, 2013, 12:00:24 PM: This is a very interesting thread to me.ï¿½ I also acquired a Harrison Heater that needs restoring and, as with many things, more information is good!ï¿½

From garage gnome:
Quote
I don't know how many people actually know this but there should be rubber grommets between the firewall and the heater core tub brace on the back of the heater. The left is an original and the right is what I replaced them with.

I have never seen nor heard of any surviving documentation on these heaters.ï¿½ I've been fooled before thinking I was looking at original when it turned out to be a PO addition from 40 years earlier.ï¿½ This grommet is interesting - and I like it.ï¿½ It would obviously help isolate vibration.ï¿½ ï¿½Where did you get the replacements from?

From Ryan_M:
Quote
I made the same connection on the head but took a different approach on the water pump.

I don't have a Parts Manual (PM) covering the 3A but wonder if y'all could check to see if the fitting matches what's listed for the 3B:

GROUP 35-21 - HEATER AND DEFROSTER
664971ï¿½ ï¿½ï¿½ 1 Elbow, heater, 45 degrees

I polled some 3B members that had an original heater and apparently that 45 degree fitting was attached to the pump.ï¿½ Mine originally had a straight fitting but I like the idea of the 45 degree fitting as it seems to clear other components with room to spare.

From athawk11:
Quote
This is another detail you might find on a Harrison installation. This is a heater hose bracket.ï¿½ It was mounted to the passenger fenderï¿½

This one also stumped me at first sighting over on the vernco.com site.ï¿½ Again, checking the 3B owner's, they showed the same bracket:

669733ï¿½ ï¿½ï¿½ 1 Bracket, support, hose

Now knowing that the 2A, 3A and 3B used this bracket I'd assume it's the same.ï¿½
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on June 21, 2013, 12:36:13 PM: I used some big grommets from the auto parts store. Don't remember the size though.

I had a very original unmolested 3B and it did not have the heater hose clamp or the 45 degree fitting... I don't have it anymore. I parted it out because the frame was gone and the tub was shot.
Title: Re: Harrison heater tips, mods and install
Post by: Matto on June 30, 2013, 07:53:38 PM: This is not a Harrison heater but it was installed on the drivers side of my 543B. There are 3 little doors on the front and sides to control air flow. It's small but works great.
(http://i40.tinypic.com/vsnvhe.jpg)
Left of steering wheel.
(http://i40.tinypic.com/2hdtf0h.jpg)
From passenger side.
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on June 30, 2013, 07:55:12 PM: I have that same heater in the Jalopy. It isn't hooked up. Do you know who makes it?
Title: Re: Harrison heater tips, mods and install
Post by: Matto on June 30, 2013, 08:19:06 PM: I had it all apart while painting and there were no tags other than the one on the fan motor, which I believe is the same motor the Harrison uses. I glad to see somebody else has one. That means the company made at least two.
;)
Title: Re: Harrison heater tips, mods and install
Post by: Matto on September 18, 2013, 06:38:08 PM: Here's some pictures of another style heater/defroster unit that came out of a 523A. It appears to have been painted olive drab originally and has a few numbers on the back and a logo that looks like the letter I in a circle. Can anyone put a name to this unit?
(http://i42.tinypic.com/29c1erp.jpg)
Front
(http://i41.tinypic.com/169gm11.jpg)
Back
(http://i41.tinypic.com/3177fq0.jpg)
Title: Re: Harrison heater tips, mods and install
Post by: Matto on November 04, 2013, 07:15:44 PM: Here's yet another heater style.
(http://i41.tinypic.com/290zwp3.jpg)
(http://i43.tinypic.com/huo9hh.jpg)
(http://i44.tinypic.com/2ba2wx.jpg)
Title: Re: Harrison heater tips, mods and install
Post by: Quebec Jeep on November 05, 2013, 08:48:28 AM: Look like a 2A style that was under driver side.
Title: Re: Harrison heater tips, mods and install
Post by: 1955CJ-5 on November 10, 2013, 09:49:43 PM: I recently re-installed my Harrison heater. From what I had read I expected the worse...

I covered it in thin bubble wrap to protect it and the rest of the jeep, and after a few tries, I reached underneath the heater and flexed the feed pipes back towards me just a bit and it slipped in....

I know all jeeps are a little different and this may not work for everyone, but it's worth a try....
Title: Re: Harrison heater tips, mods and install
Post by: 1955CJ-5 on November 23, 2013, 10:45:58 AM: In post # 8 to this thread athawk11 showed a heater hose bracket that attached to the right inner fender.

I searched a little and through the 2a page and ebay I found this..

http://www.ebay.com/itm/200915528711?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

It's a 55 chevy inner fender heater hose bracket if the link doesn't work...
Title: Re: Harrison heater tips, mods and install
Post by: garage gnome on February 13, 2014, 11:07:16 AM: I wanted to update this thread about the defroster. I've never driven my jeep in a snow storm until today. The defroster doesn't work too well when you're moving. It keeps the windshield warm when sitting still though. I'm not sure if it is from the cold air blowing on the windshield or the water temp cooling down. I didn't try putting cardboard on front of the radiator.

Driving
(http://i748.photobucket.com/albums/xx125/willyscjmj/9A1B7AE4-9685-434B-8661-0488254577A0.jpg) (http://s748.photobucket.com/user/willyscjmj/media/9A1B7AE4-9685-434B-8661-0488254577A0.jpg.html)

Sitting still for a few minutes
(http://i748.photobucket.com/albums/xx125/willyscjmj/D0BEF3E5-87FD-4667-89E8-12CBD93FD0D5.jpg) (http://s748.photobucket.com/user/willyscjmj/media/D0BEF3E5-87FD-4667-89E8-12CBD93FD0D5.jpg.html)