engine dying due to electric fan

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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.
haven't checked all of that, but will. pulling 5 on vacuum reading at idle. it's a 500 edelbrock carb, so I don't think it's too big for the 340, but it may indeed need tuning. smells very rich to me.
 
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.

OK that's OK for now. These readings are with fans running? Where is the fans power to the relays taken off, pin 30 on the relay?

ON A SIDE NOTE 14.75 is too high. When you get the fans straightened out, either start a new thread on "high charging voltage" or PM me to bump my old brain
 
OK that's OK for now. These readings are with fans running? Where is the fans power to the relays taken off, pin 30 on the relay?

ON A SIDE NOTE 14.75 is too high. When you get the fans straightened out, either start a new thread on "high charging voltage" or PM me to bump my old brain
when the engine was running, the reading at the battery was 14.75, when the fan kicked in, it dropped to 13.9, pin 30 goes through a circuit breaker to the battery. damn, I don't even get this worked out and have another problem, LMAO. isn't that the way it goes? thanks again for the help67dart273
 
when the engine was running, the reading at the battery was 14.75, when the fan kicked in, it dropped to 13.9, pin 30 goes through a circuit breaker to the battery. damn, I don't even get this worked out and have another problem, LMAO. isn't that the way it goes? thanks again for the help67dart273

I don't want to complicate this problem/ thread. That is another issue, keep it in the back of your head. Dropping to 13.9 at the battery should ELIMINATE the fan as an electrical problem.
 
What are you running for your ignition system ? points, MSD, electronic, HEI. This may be a different issue than the fan.
Is your voltage regulator solid state or mechanical ?

Is your engine effected at higher RPMs when the fan turns on ?
Is the engine missing or just dragged down by the extra load. Take the alternator belt off and see if it still stalls.
 
What are you running for your ignition system ? points, MSD, electronic, HEI. This may be a different issue than the fan.
Is your voltage regulator solid state or mechanical ?

Is your engine effected at higher RPMs when the fan turns on ?
Is the engine missing or just dragged down by the extra load. Take the alternator belt off and see if it still stalls.
Hi trapster, it's electronic ignition, and the regulator is mechanical. it doesn't seem to be effected at the higher rpm's, and it doesn't miss, just seems to lose electrical power and slow down until it dies, quickly (almost like it's running out of gas). trying to get some readings, and check a few other things. stay tuned, and thanks for your help.
 
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.
67dart273, thank you so much for posting this, it is a real eye opener. sure puts things in perspective for someone like me that isn't electrically inclined. now I can understand a lot of what has been said here in the replies, and appreciate them even more. thank you, and to all that have helped. I will get on this right away, and try to learn more. you guys/gals have been so helpful, truly appreciated.
 
all right, so much help from all of you. brain has been boggled, and thinking about problems, I didn't realize it was a recognized holiday at work until I got 2/3 of the way there this morning (dumbass), and remembered. it gave me plenty of time to go over all of your input, read articles, and get a better understanding. thanks so much, it's getting a lot clearer to me now. so.....the dart will wait today, as I have been neglecting other projects that involve a lady that loves me in spite of.......well, being me. her new weather vane will be put up, and the new radiator put in her vehicle. should buy me some time......then it's back to the dart, LOL. thanks again to you all for your help, I'll be back......assuredly, as this is far from over.
 
just want to thank all of you for your help. instead of continuing to ask questions, I am searching threads, and finding lots of information(why have you all repeat?). I have since found problems at the bulkhead, and will address. have also ordered products from crackedback (thanks Rob), and will continue to check for other problems. thanks again all, if I can't find the problem while searching, I will DEFINITELY ask for more help. again, THANKS TO YOU ALL, have been reading a lot of threads.
 
oh, forgot to mention, got all the work done on 'her' vehicle the other day, plus a trans fluid change, and what happened you might ask? .....the other day she brought home a 30 pack of Miller High Life, I'm a cheap date, but that's heaven to me :) stay well all
 
As to stalling when in going into gear, check your T-port sync
And your PVs. In an Edelbrock, that would be the metering rods. Maybe the 5" vacuum is not enough to keep the rods down, so they jump up and flood the engine.

5" of idle-vacuum is pretty freaky low. It usually indicates: a vacuum leak,a very bbbbig cam,a very low idle speed,or very late idle-timing. Another reason to see 5" at idle is if the gauge is plumbed to the sparkport, and if the primaries are really far open, which goes back to seriously late timing.
And of course there's always a chance the gauge is in error.

And one more thing; if the engine is tuned real sweet and you get the vacuum up to 11ish with a nice T-port sync, and then you put it in gear, and the Rs take a nose-dive, Well maybe the TC is NDG.
 
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thanks AJ, I have some work to do, no doubt. I'm finding some wiring problems, but will get them taken care of. also saw leakage in my plug wires, so have ordered new. was going to search for cap and rotor, any ideas appreciated (to all). will check all you say, soon. thanks so much for your help.
 
Have you tried to see if it stalls with either no fan belt at all, and/or with the field wire disconnected on the alternator, when the fan kicks in ?
 
Have you tried to see if it stalls with either no fan belt at all, and/or with the field wire disconnected on the alternator, when the fan kicks in ?
haven't been able to do that trapster, have found some wiring problems in the bulkhead that need addressed first. have been reading a lot of other threads and trying to figure out how to test the circuits and replace the bad. don't know squat about electrical, so it's time I learned. thanks again for your help, much appreciated. any help with wiring/checks would be welcomed, and I'll keep searching/reading/learning, thanks again to all
 
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