Why does my engine die when the fans kick on?

[@nickmcminn2137]

I run a 1 wire 100amp alt with pertronix ign 80w electric fan and electric fuel pumpand auto trans. With no problems. Sounds like your too lean at idle. Back out your air/Fuel screws a ¼ turn each. 1965 Mustang Coupe. If your too lean in an automatic it will die when you put it in gear. Same difference when a load is applied to the alt.👍

[@AndyKruseChannel]

That might do the trick, it's probably something simple like this. :)

[@AndyKruseChannel]

That was it, I am so dumb. Such an easy fix for this. I'll make a video about it so other will know. :)

[@nickmcminn2137]

@@AndyKruseChannel glad I could help . Just went thru something similar with mine,👍

[@AlfsMustangGarage]

You're 100% right when you say it was derived from a/c systems. We worked on a 76 firebird and it had a factory one of those and it still worked. Pretty cool and a pretty easy fix for your problem.

[@AndyKruseChannel]

Yeah, it's a cool little gadget, but this was purely a band aid. Another viewer identified the problem, I fixed it, now I don't need the solenoid. I'm going to make a video about it and post it today. I feel so silly not realizing how simple this fix was. Oh well. :)

[@donsmanufactory]

Another thing to consider is your ignition setup. If you are running manifold vacuum to the advance the extra load causes the vacuum signal to drop which backs off the timing. Extra load = slower idle = less vacuum = less timing = slower idle = less vacuum… so the motor just rambles down and dies. On my car I have manifold vacuum feeding a vacuum regulator so as the lumpy cam causes the vacuum to vary up and down the advance sees a steady signal. The relief port goes to the timed spark port on the carb. Result: initial timing set to 8*, engine idles at 18*, off idle gets timing related to timed spark port. Easy start, smoother stable idle, good drivability.

[@AndyKruseChannel]

It ended up being my idle mixture screws needed to come out a pinch more. Problem is fixed and now I don't need that solenoid. It's amazing how simple the fix was. :)

[@TheJoefussGarage]

Hello there Andy, you're all set, for yer Vintage Air project in the fall !!! Seriously, you can also use a aftermarket time delay relay, to allow one fan to start normally, and the relay is adjustable, for like 3 sec delay the second fan to start.. This will cut the startup amperage in half.. And would be very good when you do add that Vintage Air system, "hint" , "hint" !!!! I'm glad that Nick gave the heads up on the lean idle mixture as well.. God speed brother...

[@AndyKruseChannel]

Yeah, that Vintage air would be slick, it would be nice to no melt while driving this summer. That delay circuit sounds fun, I might look into that. :)

[@Glens1965]

Ford used these also on several applications mainly automatics and A/C. I believe they were referred to as a Dashpot.

[@AndyKruseChannel]

That name sounds familiar. I still think I need to dial in the carb a little better, I shouldn't be having this problem. :)

[@Glens1965]

@@AndyKruseChannel I concur. A 347 should not bog much. :)

[@dogsense3773]

Dashpot, you got it!, All these cars had them straight from the factory with automatics

[@tonygill4465]

Good carb tune!! Good budget brawler double pumper, change power valve, adjustable 4 corner. A must with light manual transmission car.

[@AndyKruseChannel]

It was the idle mixture screws, another viewer pointed it out. I went out and adjusted them, everything works now. I feel so dumb. :)

[@nickmcminn2137]

@@AndyKruseChannel bro its just part of learning. I follow this channel with my 65 so I can learn off you what I may have missed

[@tonygill4465]

@@AndyKruseChannel it’s good content your doing great!!! Carbs are a fickle but when you have them right can’t beat them.

[@tonygill4465]

@@AndyKruseChannel should do a video on vacuum gauge tuning

[@AndyKruseChannel]

@@tonygill4465 The sad part is I have a video on setting up the Idle Mixture screws and using a vacuum gauge. The tricky part is my Cam is so wild, it's had to find the best lean idle condition. Oh well, she's all good now. :)

[@4speed3pedals]

GM cars used this idle stop solenoid back in 1971. I rebuilt many a carb that used this set up. Many high perf guys had high idles and would install one of these so the engine would not run on after turning off the ignition. Even stock vehicles would do this back then when the smog regulations kicked it.This was the cure the auto manufacturers used. Now it's left up to the computer. Standard Motor Products aslo supplies this under part number ES-110. Happy O2 sensors everybody.

[@AndyKruseChannel]

IT's crazy the steps people would take to fix things so simple. :)

[@mikebroszczak5767]

Great video Andy didn't even know that that could happen

[@AndyKruseChannel]

Yeah, I think it's a product of my improperly tuned carb, but until I can get that dialed in, this is the backyard band aid I can employ until then. :)

[@vrm86gt]

I think i need this for my 347, just for a warm up fast idle on my holley hp 750.

[@AndyKruseChannel]

I guess that would work. :)

[@vrm86gt]

@AndyKruseChannel thinking I may just put it on a switch but I'd like it to cycle with the electric fans also, that would be slick!

[@stovetopstephen]

I installed this solenoid on my 289 when my ac turns on. It works great but not sure I would use it for e-fans given how often and long the fans activate. Good luck! 🤙🏾

[@AndyKruseChannel]

Hmm, but the A/C compressor kicks on and off too. Either way, this is a band aid until I can get the carb dialed in, I'm just waiting my run in line. :)

[@stovetopstephen]

@@AndyKruseChannel But I can disable the solenoid by turning off the AC…

[@juanorejel5578]

Sounds like excessive amperage for the alternator. I know you mentioned you upgraded, I've seen it numeral times. Wired to relay?

[@AndyKruseChannel]

Wired what to a relay? I know my alternator is larger than the demand, right now, but I'm trying to plan ahead for future amperage demands. I've heard before that other people experience a significant load on the motor when that alternator needs to ramp up, so I wasn't surprised by the problem I'm having. I still think I need the carb to be dialed in a little better as it should be able to feed the fuel the engine needs by the sudden demand, but I'll have to wait until I can get that thing probably tuned. :)

[@juanorejel5578]

@AndyKruseChannel meant to say the fans on a relay sorry lol. My 66 with 351w kicks the fans on and doesn't stutter and with ac on.

[@AndyKruseChannel]

Yes, fans on a relay, trigger by a switch I have in the thermostat housing. Yeah, I know it's something to do with my carb, I expect to have it ironed out once I can get it tuned by someone that knows what they're doing (not me). :)

[@davevan8864]

My factory stock 1975 Mustang II Ghia has one of those. My issue is it comes on at times I don't want it to. But when working right it does as you explain. thx

[@AndyKruseChannel]

Yeah, so far it's been performing its job perfectly. However, I don't plan on this being a long term fix as I think my issue will go away once I have the Carb dialed in. :)

[@rustybritches6747]

Ahh another mustang ii guy, cool!

[@colterhuffman1359]

No idea this existed! Just need a carb tune. Enjoy the videos. Thx.

[@AndyKruseChannel]

Yeah, I think you're right, a good tune should fix this issue and I can remove that solenoid thing. :)

[@edgargodoy7883]

Hey Andy Do you know the amps on your fans ? When the fans kick on they draw lots of amps. When the fans are running they will draw less amps. Example when the fan kicks on lets say it draws 30amps and you have a 30amp its not strong enough You would need a 40 amp relay So your engine wont die Again nit sure if you know what draw you have when the fans kick on

[@AndyKruseChannel]

I don't know the exact draw, but I know they blew the 30A fuse I originally installed, had to upgrade to a 40A fuse and it's been good ever since. However, I found the issue, another viewer pointed out the idle mixture screws, adjusted them, and now I no longer need this new solenoid. :)

[@georgieo9999]

Usually people don't know alternator has a charge rpm that need to be meet. Crank to alternator rpm ratio need to be 3:1. There's a calculation alternator rpm calculation. Ur alternator should come with a spec sheet.

[@AndyKruseChannel]

Unless someone chooses to overdrive or underdrive their alternator. :)

[@chriss-kl8ji]

Rewire the fans. Have only 1 come on. Add another relay/control for the 2nd. Have the 2nd come on at a higher temp than the first. Change and rewire the over-ride switch to DP (double pole - for both fans).

[@AndyKruseChannel]

Nah.

[@wolfthornhawkridge5705]

Do you have the fans on a relay? Or did you run them straight to the battery?

[@AndyKruseChannel]

Fans on a relay, driven by the thermocouple sensor in the thermostat housing.

[@wolfthornhawkridge5705]

@@AndyKruseChannel I’ve heard of the need for a kick up on AC cars, I’m trying to rationalize why the motor would die when there’s the additional load put on the battery. I’m running the sniper system with dual fans and a 140 amp alternator. Must be something with that 347 :) know you’ll get to the root of the issue and get rid of that step up actuator. Have you tested to see the drop in volts to the battery when the fans kick on?

[@AndyKruseChannel]

@@wolfthornhawkridge5705 It's not the load on the battery that's loading the motor, it's the alternator "going to work" because of the electrical demand when the fans kick on. The fans can run when the car is "on" but the engine is not running. I'm 99% sure it's the Carb. Another viewer recommended backing out the idle mixture screws a 1/4 turn as it may be running lean and that's why the she dies when that load is applied. :)

[@wolfthornhawkridge5705]

@@AndyKruseChannel the Powermaster alternator is supposed to kick on when there is a load on the system or the battery drops below 14 volts. Very curious now to see the root cause, keep us posted! On a different note, will your Export support fit on top, as well as, the bottom? I’m going a different route than my current Export brace. Thanks

[@AndyKruseChannel]

@@wolfthornhawkridge5705 I think it's too tall to be installed on the top.

[@domfer2540]

Knockdown linkage is for automatic. If you have a manual not needed. Could be worse, my mustang when a/c kicks in, the electric fan will not allow the engine be turned off with the key.

[@AndyKruseChannel]

Ooh, that sounds like it could be a fun problem to diagnose and chase down. Make a video about it so we can see how it goes. :)

[@Dwhinery]

Check the ground on the one wire alternator.

[@momuzy6348]

When warm or cold ? electric choke conflict ?

[@AndyKruseChannel]

Warm, it's when the fans kick on.

[@billjohnson7308]

So from what you are saying. Everytime the fans cycle (come back on ) you have to kick the accelerator pedal. Seems like a stronger solenoid might have enough strength to max entend without help. What amp is you alternator? Maybe you are losing voltage to the solenoid when the fans come on. Solenoid should not need help from accelerator.

[@AndyKruseChannel]

The solenoid was installed after I noticed the problem, not before. It ended up being the idle mixture screws. A slight turn outward and it cured my idle problem when the fans kicked on. I have since removed this solenoid.

[@stop153rz2]

I would check your voltage when the fans kick on. Not sure if you have, but maybe upgrading to an agm battery would help. I have my dual electric fan setup on an auxbeam 8 gang switch panel and my truck doesn’t flinch when they’re both turned on. 88’ 351w carbed.

[@AndyKruseChannel]

Battery is a new Redtop unit from Optima, but an AGM may help, not sure. I still think it's a carb problem and I am in queue to get it properly tuned. Until then, this is my band aid fix. :)

[@robertclymer6948]

I love the auxbeam products! I power my Gt fogs lights on one relay, and on other two relays, I run my dual 9 inch pusher fans wired for auto or toggle switch indash for manual usage. Love being able to manually run the fans when I want to.

[@mrbonafied78]

I used to have a large stereo system in my car and it would have the volts down to 9 volts at a stop light. My car would never die. So hmm it might be something else. I’d upgrade all my cables to at least 1/0. Get that alternator tested and throw a charge on the battery

[@AndyKruseChannel]

It was the idle mixture screws, another viewer pointed it out. I went out and adjusted them, everything works now. I feel so dumb. :)

[@seano7971]

Check your spark plugs. One on each side. They will tell you your mixture.

[@AndyKruseChannel]

Plugs are good, it ending up being the idle mixture screws. It's fixed now. :)

[@flyingfruitbats]

Think you need to work the solution differently, this is backyard electrics and not solving the issue. Don't think you want anything holding the throttle open without your control...

[@AndyKruseChannel]

I agree, I'm fairly certain that I shouldn't need this switch to keep the motor alive. I'm expecting to have this solved once I can get into have my setup tuned. The line is long and I want to drive the car, so this band aid is working (although not ideal) until I can get there. :)

[@richardporter4281]

Can't beat a mechanical Flexi fan no problems

[@AndyKruseChannel]

Depends on your goals. Mechanical fans apply a load to the motor, robbing it of a few ponies, at all times. Electric fans are temporary and depending on the speed and/or temperature, they don't even come on, reducing the electrical demand of the car. However, I promise I wouldn't be having this issue if I left my mechanical fan in place, because even if I went to a one-wire, it would be a smaller amperage unit, and therefore it's load on the motor may not play a role in the engine dying. So, you get half a point this round. :)

[@MrVitoQ]

The solenoid should be mounted higher so that the plunger is actually pushing on up tab of throttle lever. Due to mechanical advantage it is struggling to push throttle linkage being it is closer to pivot point. If plunger is moved to upper part of throttle linkage it should be able to over come and fully extend with out blipping throttle.

[@AndyKruseChannel]

Hmmm, you might want to let Holley know, this is their part on their carb bolted in the exact spot they said it should go. :)

[@pauls7751]

You may be barking up the wrong tree. Low voltage or heavy voltage draw should not effect your carb adjustments or idle mixture screws unless you have an electric fuel pump. Fuel system and electrical system should not be related. You should look at your ignition system. Low voltage will effect spark. I've been running a 100a powermaster alternator for over 10 years without problem. I have A/C, single cooling fan and MSD distributor with an MSD 6AL ignition box. Recently my car was running poorly. I found the alternator had gone bad. The engine was trying to run on the battery alone that could only supply 10v to 11v. Replaced with a Tuff Stuff 140a alternator. Problem solved.

[@AndyKruseChannel]

It wasn't a low voltage problem, it just ended up being my idle mixture screws. Issue is not fixed and I don't need that Solenoid anymore. :)

[@pauls7751]

@@AndyKruseChannel what I don't understand is why the engine would die when the fans came on. If it was idle mixture wouldn't it die when the fans were off also? Anyway glad you got it fixed. My car/Holley likes the idle mixture screws about 1 1/4 turn out.

[@AndyKruseChannel]

@@pauls7751 It's not the fans specifically, it's the electric demand they have, which in turn makes the Alternator work harder, and therefore puts the extra load on the motor and it can't keeping running if it's too lean at idle. My driver side idle mixture screw was only 1 turn out, but the passenger side was 1-1/4 turns out. By adjusting the driver side by 1/4 turn, the engine didn't die anymore. It was glorious. :)