m1008 wire problem

[BigRedMachine]

This truck keeps frying starter silonoids ard relays. I've gone through four starters in six months. I would like to know how to convert 24v to 12v. Can someone tell me what parts and steps on how to do this?

 

[uscgmatt]

I would get a schematic and check you wire harness, sounds like some bad wires somwhere. Converting to 12vdc only makes future troubleshooting more difficult.

Matt

 

[BigRedMachine]

schematics

did this and gone though wireing only thing I foundwas p#15599225 was burnt in two. could this be the problem. I was looking for this part but can't find it . Can I use a fuseable link to bypass it.

 

[uscgmatt]

I have no idea what that part is. Can you reference it to the wiring diagram or to the location of it on the truck?

Matt

 

[BigRedMachine]

reference

this is a 3 piece wire with 3 seperate supressors . wire is only 3 " and runs from 3rd post on top firewall board down to 1st post on bottom firewall wiring board problem started with stater solenoid hung up and hasnt been right since
Image (It is your responsibility to verify the accuracy of these images)

Reference Numbers (Part Numbers)

15599225

​

 

[uscgmatt]

The suppressors (capacitors) are only used for noise reduction for radios. It wont cause starter damage. Replacing suppressors w/ fuseable links will make smoke as you are making a short. Have you replaced the starter relay under the dash?

Matt

 

[BigRedMachine]

relay

yeah I replaced the relay after the 1st time this time with resettable breakers so as not to burn up anymore starter solenoids worked for a while until tonight and truck tried to crank by itself sidenote - ran truck without supressor for a while it ran fine but gen 2 light stayed on with supressor in place gen 2 light went off . when truck tried to crank itself said suppressor fried intwo

 

[ida34]

I am a little fuzzy on exactly what you are doing. You mentioned you replaced the relay with a circuit breaker. They do not do the same thing or even close. If you replace a relay with a circuit breaker the line will be on all the time. Your starter would run the minute you connected the batteries or reset the breaker. The relay activates with 12 volts from the ignition switch and this provides 24 volts to the starter and the attached solenoid on top of the starter. The starter solenoid then sends power to the starter. It has a built in relay. Basically there are two starter relays. The relay under the dash and the relay in the starter solenoid. The suppressors are capacitors that take electrical noise out of the system. They are attached to motors like the blower motor and the alternator as they make electrical noise that can be heard on the radio. It sounds like you have a problem in your number 2 alt. Converting to 24 volt will not fix any problems unless the problem is in the 2nd alt and you remove it when converting. Something is providing power to the start circuit either on the 12 volt side or the 24 volt side. You need to find the short to power in the system. Most of the time the relay under the dash is the usually problem with phantom starting. If you replaced this relay with anything except the proper relay I would start by putting the right part back in and going from there. I think your alt problem is unrelated unless some wires melted into one another shorting the starting system to the charging system. I hope this helps. Post some pics of what you are talking about and we can try to help more.

 

[uscgmatt]

yeah I replaced the relay after the 1st time this time with resettable breakers so as not to burn up anymore starter solenoids worked for a while until tonight and truck tried to crank by itself sidenote - ran truck without supressor for a while it ran fine but gen 2 light stayed on with supressor in place gen 2 light went off .

With all due respect, can you use some punctuation. It sounds like you changed the relay out with resetable breakers. Is this the case? With out knowing how much rewiring has been done to the truck, I would say to check the connections on the relay then change it out. The only items in the circuit that can make it start by itself are the key switch and relay. I hope this helps.

Matt

 

[uscgmatt]

IDA34, wow you typed all of that in less time than it took me to type mine. I need to work on my typing.

Matt

 

[ida34]

I just looked at your attachment. Those are 24 volt terminal strips on the firewall. They are not suppressors and what you have circled does not go on the alt. It looks like a fusible link from one strip to the other. If this is what burned out it may be that the starter connects to this block and when the starter went belly up it took out this fusible link. I can take a look at mine and get back to you but I would guess you had the relay go out under the dash causing the starter to run and it took out the relay after the fusible link over heated under the current. I bet when you took the link off this is what triggered the charge light. Either way you have to have 24 volts at the bottom strip. Confirm what relay you replaced under the dash.

I just looked and the manual does say the thing that looks like a fusible link is a capacitor. I can check my truck to see if it is just a link and a typo in the manual. I will poke around on my truck and try to post back.

Below is the relay under the dash. The one you want is the big silver one. Not the two smaller ones.

 

[ida34]

Looking at the schematic posted I am wrong. The top longer terminal strip is 24 volt and the one at the bottom is just a negative terminal post. The suppressor must be a weird capacitor.

 

[ida34]

I am pretty quick on the keyboard Matt.

 

[ida34]

Red,
This is a link to instructions on converting to 12 volt only system. I would fix the problem first then convert it I were you.

Chuck

 

[BigRedMachine]

reply

i apologize for my vagueness and lack of punctuation last night, it was late and i was tired. what i did was put a breaker from switch to relay under dash and a breaker from relay down to starter solenoid. my thinking in doing this was this would protect the relay from frying as well as the stater solenoid while i was searching for dead short. i have the entire TM and experience in mechanicing , but this dead short has got me chasing my tail. i really do appreciate everyones help and suggestions. im sure theres something i'm just overlooking and i welcome your input.

 

[BigRedMachine]

o

ttt