Engine Dies...
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From: Galvin, WA
Engine Dies...
The truck is an 86' F250HD 4x4 351W w/ DS2.
My problem is the engine is alway's dieing, loss of spark not fuel. I've no idea what the problem is...
I've replaced the brain box, coil, cap & rotor, spark plug's & wires. As far as the ignition system goes i've replaced pretty much everything minus the Dizzy and wiring harness.
I'm thinking its the Dizzy but not certain. After the truck dies i've pulled the coil wire off of the cap and put a screwdriver in it the check for spark, sometime's i get nothing and sometimes i get a very weak spark.
I used to have an 81' F100 w/ a 302 and DS2, That truck had a voltage regulator on the passanger fender. I'm bringing that up only because i've noticed my 86' does not have that...
Also, I can't check anything due to me being in Afghanistan at the moment. Any input would be great! Thank you!
My problem is the engine is alway's dieing, loss of spark not fuel. I've no idea what the problem is...
I've replaced the brain box, coil, cap & rotor, spark plug's & wires. As far as the ignition system goes i've replaced pretty much everything minus the Dizzy and wiring harness.
I'm thinking its the Dizzy but not certain. After the truck dies i've pulled the coil wire off of the cap and put a screwdriver in it the check for spark, sometime's i get nothing and sometimes i get a very weak spark.
I used to have an 81' F100 w/ a 302 and DS2, That truck had a voltage regulator on the passanger fender. I'm bringing that up only because i've noticed my 86' does not have that...
Also, I can't check anything due to me being in Afghanistan at the moment. Any input would be great! Thank you!
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Joined: Nov 2007
Posts: 22,415
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From: Denver Metro Area, CO
The pickup in the distributor instructs the module to fire the coil at the right times.
If you can't check anything, then I would replace that pickup (or the entire distributor, I understand getting those things out can be a pain).
If you can't check anything, then I would replace that pickup (or the entire distributor, I understand getting those things out can be a pain).
Fleet Mechanic
Joined: Jul 2011
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Voltage regulators are usually dependent on what generation alternator you've got on your truck, as I understand it. Some have an external regulator, and others have an internal regulator.
I don't know what else could be causing the problems you're having other than the distributor's pickup coil.
Going through the trouble to replace the pickup coil seem kind of silly when you could just could a whole new distributor...
Just my 0.02$.
EDIT: I think me and Chris are spot on.
I don't know what else could be causing the problems you're having other than the distributor's pickup coil.
Going through the trouble to replace the pickup coil seem kind of silly when you could just could a whole new distributor...
Just my 0.02$.
EDIT: I think me and Chris are spot on.
FTE Legend
Joined: Jul 2010
Posts: 32,875
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From: Northeast, OK
The truck is an 86' F250HD 4x4 351W w/ DS2.
My problem is the engine is alway's dieing, loss of spark not fuel. I've no idea what the problem is...
I've replaced the brain box, coil, cap & rotor, spark plug's & wires. As far as the ignition system goes i've replaced pretty much everything minus the Dizzy and wiring harness.
I'm thinking its the Dizzy but not certain. After the truck dies i've pulled the coil wire off of the cap and put a screwdriver in it the check for spark, sometime's i get nothing and sometimes i get a very weak spark.
I used to have an 81' F100 w/ a 302 and DS2, That truck had a voltage regulator on the passanger fender. I'm bringing that up only because i've noticed my 86' does not have that...
Also, I can't check anything due to me being in Afghanistan at the moment. Any input would be great! Thank you!
My problem is the engine is alway's dieing, loss of spark not fuel. I've no idea what the problem is...
I've replaced the brain box, coil, cap & rotor, spark plug's & wires. As far as the ignition system goes i've replaced pretty much everything minus the Dizzy and wiring harness.
I'm thinking its the Dizzy but not certain. After the truck dies i've pulled the coil wire off of the cap and put a screwdriver in it the check for spark, sometime's i get nothing and sometimes i get a very weak spark.
I used to have an 81' F100 w/ a 302 and DS2, That truck had a voltage regulator on the passanger fender. I'm bringing that up only because i've noticed my 86' does not have that...
Also, I can't check anything due to me being in Afghanistan at the moment. Any input would be great! Thank you!
Unless you have multiple problems, which I doubt, a significant clue is that you sometimes get a weak spark. Having no spark can be several things, but having a weak spark is either the DS-II box or the coil. I say that because the DS-II box could only partly charge things and, therefore, give a weak spark. I think the coil might be able to do that if it has insulation going bad internally, but in my experience coils either work or they don't.
So, I would put my money on the DS-II box, even though you've already replaced it. The symptoms point directly to it, with a remote possibility of it being the coil.
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From: Galvin, WA
Honestly, If the problem might be in the dizzy i Would just replace the whole thing rather than just a part of it. They are cheap enough.
So you are thinking it "might" be the dizzy then?
CT - Do you have any input on that voltage reg. that was on my 81' but not on my 86'? I'm really not sure if the PO changed thing's or not...
So you are thinking it "might" be the dizzy then?
CT - Do you have any input on that voltage reg. that was on my 81' but not on my 86'? I'm really not sure if the PO changed thing's or not...
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From: Galvin, WA
Fast reply's! Thanks guy's!!!
Reguarding the voltage reg. It make's sence what you're all saying.
As far as the brain box goes, I really dont think the problem is in there. I still have the old one under the seat. When i first had these problem's i though the box was it. But i know my old one is still good as with the new one...
Reguarding the voltage reg. It make's sence what you're all saying.
As far as the brain box goes, I really dont think the problem is in there. I still have the old one under the seat. When i first had these problem's i though the box was it. But i know my old one is still good as with the new one...
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Joined: Nov 2007
Posts: 22,415
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From: Denver Metro Area, CO
Gary is correct about the transition from 1G to 2G alternators; my 1986 DD has the 2G (with built-in regulator) I believe this transition occurred around 1984.
If you had an ohmmeter you could test the distributor pickup, and parts stores can check a DS2 box to at least some degree but heat-related failures can be hard to diagnose.
If the problem didn't go away with a new DS2 box, I would swap the old one back into place, this is the best thing to do when diagnosing problems like this - change one thing at a time; if that doesn't fix it, that isn't the cause of the problem so change it back to how it was and proceed with the diagnosis.
If you had an ohmmeter you could test the distributor pickup, and parts stores can check a DS2 box to at least some degree but heat-related failures can be hard to diagnose.
If the problem didn't go away with a new DS2 box, I would swap the old one back into place, this is the best thing to do when diagnosing problems like this - change one thing at a time; if that doesn't fix it, that isn't the cause of the problem so change it back to how it was and proceed with the diagnosis.
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From: Galvin, WA
Thank you!
I did use the old box and old coil even after i bought new one's. It doesn't make a difference with the old or new part's.
I think i'm just going to go ahead and order a new Dizzy and install it when i get back home in about 4 month's.
Anyone recommend a certain Dizzy from a certain place?
I did use the old box and old coil even after i bought new one's. It doesn't make a difference with the old or new part's.
I think i'm just going to go ahead and order a new Dizzy and install it when i get back home in about 4 month's.
Anyone recommend a certain Dizzy from a certain place?
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Thread Starter
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Senior User
Joined: Dec 2010
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From: Galvin, WA
Can anyone recommend a good stock replacement Dizzy?
This is what i'm looking at...
Cardone Remanufactured 30-2895 - Distributor | O'Reilly Auto Parts
This is what i'm looking at...
Cardone Remanufactured 30-2895 - Distributor | O'Reilly Auto Parts
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