Warm Air Blower in Engine Compartment

[red-beard]

I have a 1971 914-4 and it's getting cold here in the Northeast. It looks like the heater hose from the drive side connects across the engine bay to the passenger side and in between there is an electric blower.

The blower is _not_ mounted and is loose in the compartment. One of the wires to the blower is broken, so it is not operating.

OK the question: Where is this blower supposed to be mounted. I can fix it with replaced wiring, but I need to mount it first.

Any help would be appreciated.

James

[This message has been edited by red-beard (edited 10-26-2000).]

[efeinsmith]

The fan attaches to a mounting bracket that is bolted to the engine blower housing. The fan is turned on by a contact in the heater control lever. on the console hump. If you go to the 914 section here in Pelican Parts, there will be electrical diagrams, so you can figure out how to repair the wiring.

[red-beard]

OK, so it sits in front of the engine blower. In the small gap between the engine and the firewall? OK. I think I know about where to set it. The wiring should be OK, as 1 of the two wires is broken and a butt splice from Radio shack should work.

Thanks! I may be able to drive it for a few more weeks! They are predicting snow on Saturday

James

[This message has been edited by red-beard (edited 10-26-2000).]

[mejulihn]

On some 914 heater fans there is a single warm air hose in the engine compartment that connects the fan to the left-side heat exchanger. In others there are two warm air hoses with the longer hose that crosses over the engine bay to connect to the right-side H.E. as well. This allows you to get heat to both sides of the cockpit. If you have a one-hose set-up you can get a Y-adapter (I think I got one from a 911) that goes on the discharge of the heater fan to create a two-hose set up. The mounting bracket for the fan is located in the front left corner of the engine compartment, below and to the right of the relay box. If the bracket is missing, you should be able to fabricate a functional replacement with some angle brackets from your local hardware store and a 3" radiator hose clamp.

[red-beard]

It looks like I have the 2 hose blower. I expect someone tried to retrofit the better blower onto this car. I'll see what I can do to mount this tonight or over the weekend, then fix the broken wire. I don't care about the heat as much as being able to defog the windshield.

Thanks,

James

[Dave at Pelican Parts]

James, the dual-outlet fan you describe is what came stock on the 70-72 ones. The 73-74 only had one outlet, and the 75-76 had a splitter on the single outlet.

The early fan should mount on a bracket that sits up above the engine cooling fan shroud. I believe that the car on the cover of the Haynes manual has this type of fan. Take a look and you may be able to tell where it mounts. It sounds like your braket might be missing.

The later, single-outlet fans are what live over on the left side of the engine bay.

The fan is powered by the "heater blower relay" on the relay board, which I think is the rear-most one. This relay is wired so that the switch under the heater control ("DEFROST") lever grounds one of the inputs and switches the relay on, powering the fan. The switch should only be grounded when the lever is pulled up all the way, though I imagine this can be adjusted somewhat.

--DD

[efeinsmith]

The blower is above the engine fan housing on the driver side. The fan fits into a round cutout on the bracket and has an outlet fitting on each side. If you look at the Pelican parts diagrams for the 914, there is a picture under "Hot Air Blower" which shows both the blower and the mounting bracket.

BTW, if someone changed the blower, I have a spare blower and mount bracket in my parts collection, that came off a 72 1.7L

Eric

[mejulihn]

For efficient defrosting/defogging of the windshield, you will of course need both sides to blow warm air. So the two-hose set up is preferred for both heating the cockpit on both sides and defogging the windshield.

[HarveyH]

I live in SE Pennsylvania, and while it doesn't get as cold as some places in the USofA, it will get fairly brisk on occasion. My 74 2.0 has had the splitter nozzle added by the PO, and while it does force air through both sides, the flow rate is what I would call marginal at best. Even after runing twenty minutes or longer I will have to keep cracking the side windows to keep the windshield clear, and It never gets what I would call warm inside the car at speed. One of the Pelican Tech Articles describes ading a second blower to the system, check it out. Haven't done it myself yet, but it's on the list.
Harvey

[Bleyseng]

I rebuilt my 76 2.0L this past year and switched to 73-74 SSI heat exchangers and kept the single outlet booster fan I had. What a difference it made, I can defrost the windshield in about 2 blocks and the car is all warmed up in a few minutes, very hot in 5 minutes. Now this is when it's 35 degrees out too! I think also what makes a difference too is I replaced, re-installed, installed ALL the parts that came orginally. I made sure all the air from the blower is routed the thru the motor or into the heaters. Ill fitting pieces, missing pieces, lost rubber gaskets will spill the air out with a loss of pressure where you need it. I remember these cars when they were new and they heaters worked great then, like for going skiing! Check your heating system carefully and replace, find the missing parts!
Geoff
76 914 2.0L

[7391417]

For all of you having trouble getting enough warm air out of your system or defogging your window, read my tech article on Pelican, If you follow that you will love your 914's heater system!! http://www.pelicanparts.com/techarticles/914_turbo_fan/914_turbo_fan.htm

-Brent

[red-beard]

OK, I was able to mount the blower. I finally found a picture of how it sat in the compartment (thank-you Haynes manual, and a boo to the expensive Porsche manuals I purchased!). It looks like the tabs used to mount the fan fatigued and broke. I ended up drilling a new hole in the bracket, then using aircraft snips to reshape the bracket. Only now do I find that the power is not there. Now the re-wiring begins...

[bowlsby]

If you don't have power to this fan...

Check the round black heater blower relay on the regulator plate and the fuses first! Haynes can tell you which one it is...

[red-beard]

I ran through both the relays and the fuses last night, and replaced the fuse and tried a couple of relays (I think they are work...). Anyway, I'll be working on in in earnest, now that the day time temps are in the 30's and the primary winter car is in the shop...

Temp setup until I have time to troubleshoot the wiring...

[red-beard]

OK, into the dunderhead dept, I was troubleshooting the wrong knob...Who has info on the setup of the red floor mounted heat/blower controller ?

[mejulihn]

The red-handled heat/defrost lever on the tunnel performs two functions: 1) it operates the heater flapper boxes located on the end of the heat exchangers via a wire cable when you pull the lever up, and 2) in the "on" position it grounds a contact on the bottom of the lever to complete a circuit to the heater relay in the engine bay.

[red-beard]

OK, it looks like the switch for the heater control knob is missing. I hooked up the hoses to the blower (Which helped anyway, since I'm not feeding the engine compartment 1/2 of my engine fan air). I also found that the drivers side flapper valve had lost an internal screw, 1/2 of it would keep it closed all the time, even if you moved the lever.

Even without the blower operating, what a difference. When I get the blower working, I'll probably be too hot! Thanks to everyone for thier help.

James

[mejulihn]

Glad to hear you have warm air again, James. I am not quite sure what you mean when you say the "switch for the heater control knob is missing". The "switch" is the red-handled control lever itself contacting a ground wire that is connected near its base. Is part or all of the lever missing? Is the ground wire to the base of the lever still connected?

[This message has been edited by mejulihn (edited 11-17-2000).]

[red-beard]

Well, that explains why it is "missing", I thought it would have a contact switch like the hand brake switch. OK, I need to review the wiring on this guy, after I replace the blower motor with one that works. This motor will not turn, now. I may take it apart this weekend and see what is wrong, impeller or the motor, or both. I have a spare impeller/motor off my "parts" car, which isn't installed. I will get a replacement for that one, as I need to put the heating system together for that car. After I fix the brakes...

I do have to replace my girlfriend. She and the Porsche's are not compatible.

James