engine dying due to electric fan

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wiring-diagram-jpg.jpg
The way I read you schematic your system should be fine. The alternator should be wired directly to the battery and the battery directly to the relay.
Something (battery or alternator) would have to be really bad to kill the engine when the fan relay closed. Make sure none of this wiring runs through
your bulkhead connector and recheck your install. Sum-ting-wong------good luck!
 
I'm pretty sure the fan is blowing out the fire in the cylinders. Yeah. That's got to be it. Maybe you should have bought a less powerful fan.
you might be on to something WoodenNickle, it did blow the candle out when I was searching the wire routing. thought I slowed it down enough with the baseball cards and clothes pins, makes it sound really tough.
 
I want me some mustard with mah biscuits.
 
The way I read you schematic your system should be fine. The alternator should be wired directly to the battery and the battery directly to the relay.
Something (battery or alternator) would have to be really bad to kill the engine when the fan relay closed. Make sure none of this wiring runs through
your bulkhead connector and recheck your install. Sum-ting-wong------good luck!
thanks DesertRat, did check the routing, and everything is as shown in diagram. but, the 85 (blue) which is designated '12 volt power source' is hooked into the back of the ignition switch. I'm wondering if there is a better place for this, or if it wouldn't matter because of the draw from the fan itself on the battery/alternator?
 
thanks DesertRat, did check the routing, and everything is as shown in diagram. but, the 85 (blue) which is designated '12 volt power source' is hooked into the back of the ignition switch. I'm wondering if there is a better place for this, or if it wouldn't matter because of the draw from the fan itself on the battery/alternator?
Yeah it should be good there. Next thing would be the voltage regulator, may be sensing or not the additional load when the relay closes.
 
Yeah it should be good there. Next thing would be the voltage regulator, may be sensing or not the additional load when the relay closes.
looks like I'm going to have to learn to use my meter. will do some checking and get back on here with the results, after I do some reading/video watching that is. thanks again
 
please, I'm open for suggestions. actually, the original post is for help. and yes, with the fan on the ignition switch, it only runs when the key is on. any help is appreciated, more than appreciated. what do you (or anyone else) suggest? can the second power wire be connected to the battery as well? or does it need another power source?
I have my electric fan connected to the ignition switch so it only comes on if the cars ignitions on and to the thermostat relay switche. That way it’s not always on, only when the temp hits 160
 
I have my electric fan connected to the ignition switch so it only comes on if the cars ignitions on and to the thermostat relay switche. That way it’s not always on, only when the temp hits 160
that's how this is too Josh, but when the fan kicks on, it's definitely robbing power and making the engine die. doing some tests, will post readings in a while, thanks for the input.
 
Sounds like ground is good,but body/engine/battery need good clean connections. And fan neg needs to be checked too. Reg is on body,alt is grounded to engine. Wierd things can happen.
 
Sounds like ground is good,but body/engine/battery need good clean connections. And fan neg needs to be checked too. Reg is on body,alt is grounded to engine. Wierd things can happen.
trying to check every connection as I am checking parts in the system. again, sometimes it's the easy things that stump us. getting info on readings, but checking in too. thanks Tooljunkie, and everyone for that matter.
 
The relay is wired fine for where each blade should be connected as long as the 85 wire is switched 12v+.

Those instructions are generic and do not cover each specific car that was ever produced.
 
The relay is wired fine for where each blade should be connected as long as the 85 wire is switched 12v+.

Those instructions are generic and do not cover each specific car that was ever produced.
checked the relay, it's good, gate opened, and when power put to it, was at zero resistance. here's the alternator crackedback, as you have the wire around. thanks again, and as I said, only info on it is Ultima 01-0160. will have other results shortly.

alt 1.jpg


alt 2.jpg


alt 3.jpg
 
You need to get busy with a voltmeter. That is the only thing that will answer these questions. Some key points to check with motor running, and a jumper wire so you can jumper the fan stat on and off for tests:

"What is voltage" with / and without fan running, with engine running "fast idle"

...........at starter relay stud

...........at bulkhead connector the "big black" socket (ammeter/ alternator}
...........at bulkhead connector the "big red" socket.(fuse link/ red to starter relay)
...........at alternator output stud
...........at the "key" side of the ballast resistor, or where that would be if not used, AKA the dark blue feed coming out of the bulkhead connector

Crackedback on here knows what he's doing as well
 
You need to get busy with a voltmeter. That is the only thing that will answer these questions. Some key points to check with motor running, and a jumper wire so you can jumper the fan stat on and off for tests:

"What is voltage" with / and without fan running, with engine running "fast idle"

...........at starter relay stud

...........at bulkhead connector the "big black" socket (ammeter/ alternator}
...........at bulkhead connector the "big red" socket.(fuse link/ red to starter relay)
...........at alternator output stud
...........at the "key" side of the ballast resistor, or where that would be if not used, AKA the dark blue feed coming out of the bulkhead connector

Crackedback on here knows what he's doing as well
thanks 67dart273, have been out there checking what I can, as I am not good with electrical.....but learning. I'll have to get back out there and do what you mention. here's the numbers I came up with, but did not have a 'fast' idle (although I did have to idle the engine up to keep it running while testing). so, here they are:
battery- 12.55 volts, 649 cca
alternator- 14.75, 13.9 when fan kicked on
coil- 6.7, and roughly stayed the same while running and with fan running.
I did check the relay for the fan, that checks out. the fan seems to work properly, cycles.
thanks to all that are helping, I do so much appreciate you all.
 
Yep, stock round back.
That and a 600 RPM idle may very well kill the engine with 6-7 volts at the coil when the fan comes on.

This could be as simple as moving the switched power wire for the relay from what may be the "run" terminal of the ignition switch instead of the start or accessory circuit.
 
Yep, stock round back.
That and a 600 RPM idle may very well kill the engine with 6-7 volts at the coil when the fan comes on.

This could be as simple as moving the switched power wire for the relay from what may be the "run" terminal of the ignition switch instead of the start or accessory circuit.
thanks for the input TrailBeast, not sure how to check that, electrical idiot here. I can say that the fan runs in the 'run' key position. even if the engine dies, the fan will continue to run (would that mean it's correct?). I will see if I can tell where it's hooked up for sure. if you can help with a test, I'd appreciate it. thanks again
 
You need to get busy with a voltmeter. That is the only thing that will answer these questions. Some key points to check with motor running, and a jumper wire so you can jumper the fan stat on and off for tests:

"What is voltage" with / and without fan running, with engine running "fast idle"

...........at starter relay stud

...........at bulkhead connector the "big black" socket (ammeter/ alternator}
...........at bulkhead connector the "big red" socket.(fuse link/ red to starter relay)
...........at alternator output stud
...........at the "key" side of the ballast resistor, or where that would be if not used, AKA the dark blue feed coming out of the bulkhead connector

Crackedback on here knows what he's doing as well
what would you suggest for 'fast idle'? fast idle cam? rpm wise? trying to stumble through this, thanks again
 
thanks for the input TrailBeast, not sure how to check that, electrical idiot here. I can say that the fan runs in the 'run' key position. even if the engine dies, the fan will continue to run (would that mean it's correct?). I will see if I can tell where it's hooked up for sure. if you can help with a test, I'd appreciate it. thanks again

The point there was that if the relay pulls it's switching power right off the same wire that goes to the coil it could very well do what you are saying since your coil power supply seems to be about 6-7 volts. (which is a volt or two low)
Then when the relay activates the power to the coil dies down even farther.

Also a 7-800 RPM idle would be about normal, and if yours is below that the roundback alternator isn't putting out enough to maintain enough voltage to fire the coil sufficiently (especially after going through a ballast resistor)

My comment about the roundback alternator was because they have a very low charging output at idle (unlike the squareback style)

In your specific case I would disconnect that wire from the ignition and use the accessory circuit instead.
This can be found at the fuse block and is only powered with the key on, so it will all work the same. (except the relay won't be pulling power from the coil)
There are usually extra spades on the back of the fuse block where you can add the relay activation wire.

Betcha it works.:D

Sorry for further complicating this Rob, Rob and Del. :D
 
The point there was that if the relay pulls it's switching power right off the same wire that goes to the coil it could very well do what you are saying since your coil power supply seems to be about 6-7 volts. (which is a volt or two low)
Then when the relay activates the power to the coil dies down even farther.

Also a 7-800 RPM idle would be about normal, and if yours is below that the roundback alternator isn't putting out enough to maintain enough voltage to fire the coil sufficiently (especially after going through a ballast resistor)

My comment about the roundback alternator was because they have a very low charging output at idle (unlike the squareback style)

In your specific case I would disconnect that wire from the ignition and use the accessory circuit instead.
This can be found at the fuse block and is only powered with the key on, so it will all work the same. (except the relay won't be pulling power from the coil)
There are usually extra spades on the back of the fuse block where you can add the relay activation wire.

Betcha it works.:D

Sorry for further complicating this Rob, Rob and Del. :D
well, I got news for you TrailBeast.......you're my newest best friend, LOL. did a cheat and hooked it up to the fused side of the radio, runs perfect. no hesitation whatsoever. thank you for your help, along with all the others. this site is/has been a great knowledge site for me for a while now. will have to figure out how to set this up correctly, as I found some other wires connected as well. I'm sure I'll be asking more questions, but the nice part, I'm learning something new today, and hopefully making some new friends. thanks again for the help all.
 
well, may have spoke too soon, LOL. still dying when put in gear, but getting better! I'll keep checking, and asking, and working at the problem. starting to think the carb is too rich, but I hate to touch a carb before checking everything else. I'm betting there are some others that would agree with that?
 
What is the timing for initial/idle and total?

Low idle and fat carbs are sometimes a symptom of a different item being set poorly. If the engine drops more than about 100 rpm in gear, not enough initial timing is a typical issue. Hotter camshaft and using the "book" timing is another.
 
battery- 12.55 volts, 649 cca
alternator- 14.75, 13.9 when fan kicked on
coil- 6.7, and roughly stayed the same while running and with fan running.
I did check the relay for the fan, that checks out. the fan seems to work properly, cycles.
thanks to all that are helping, I do so much appreciate you all.

Battery.........is that running? If so IT IS NOT CHARGING or the alternator is not keeping up with the fans.

IF the battery v is "running" then the higher voltage at the alternator post indicates that there is a voltage drop in the harness, a BIG one.

I quote this article a LOT. Some folks don't like how it's done, but whether you do this 'as per article" or take another route, this article DOES give a very good overview of the problem:

Catalog

The simplified diagram in that article:

amp-ga18.jpg


Gives you a VERY good "view" of the trouble points in these girls. EVERY SINGLE TERMINAL POINT mentioned below must be checked, and by that I mean "with a voltmeter" to "bracket" the area of concern. In no order the troubles are:

terminations at and the fuse link itself

BIG trouble is the big red and big black ammeter/ charge wires going through the bulkhead connector

The ammeter itself, internally, as well as defective/ loose terminals at those ammeter wires

The ignition switch connector

The contacts IN the ignition switch itself

In very rare cases (but it happens) the "welded splice" can fail. This is a factory welded splice in the black ammeter wire, up under the cluster, which feeds off as shown in the diagram.
 
Battery.........is that running? If so IT IS NOT CHARGING or the alternator is not keeping up with the fans.

IF the battery v is "running" then the higher voltage at the alternator post indicates that there is a voltage drop in the harness, a BIG one.

I quote this article a LOT. Some folks don't like how it's done, but whether you do this 'as per article" or take another route, this article DOES give a very good overview of the problem:

Catalog

The simplified diagram in that article:

View attachment 1715130063

Gives you a VERY good "view" of the trouble points in these girls. EVERY SINGLE TERMINAL POINT mentioned below must be checked, and by that I mean "with a voltmeter" to "bracket" the area of concern. In no order the troubles are:

terminations at and the fuse link itself

BIG trouble is the big red and big black ammeter/ charge wires going through the bulkhead connector

The ammeter itself, internally, as well as defective/ loose terminals at those ammeter wires

The ignition switch connector

The contacts IN the ignition switch itself

In very rare cases (but it happens) the "welded splice" can fail. This is a factory welded splice in the black ammeter wire, up under the cluster, which feeds off as shown in the diagram.
no, battery was sitting before starting (12.55), then, after starting, the reading was 14.75, figuring that was alternator charge? trying to give best information I can, from others giving me information as to what to check. will check others you mention, as did another, tomorrow. thanks for your input, appreciated.
 
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