trouble with eng starting need help

[billsbowtie]

it's on my 68 it want start unless i run a wire from the hot post to the dis. and when i want to turn it off i have to unhook the wire to kill it. also without the wire hooked up the eng. turns fast but when i hook the wire up so it will start the eng. turs real slow .so far i have replaced the dis. its elec. dis. replaced the voltage reg. and now i am thinking of replacing the under hood wiring harness. has anyone run into this before.

[Rack Man]

I'm not much of an electrical guru...but I had a similar experience once with an old Camaro I had....and the culprit was with the "Ballast Resistor"....Not sure if its applicable on HEI's.....Hopefully someone else can elaborate on it a bit or count it out?...By the way, what HEI set up do you have?

[mclairmo]

Could it be the ignition switch? The ignition switch allows battery current to flow from the battery to the distributor. I would find a wiring diagram and follow the wiring to determine the path of current from the battery to the distributor and determine what items may be faulty and not allowing current to get to the distributor. Also, make sure everything is wired correctly and all fuses are good. Also, make sure the engine is grounded to the body and the body is grounded to the frame. Bad grounds often create these type of electrical gremlins.

[BAGNDRAGIT]

how does the wiring in the truck look overall? how about the ignition switch as stated above?

you may have a bad connection somewhere. where is you distributor normally recieve 12v+ from, the fuse block or an independent circut?

also hows the in cab fuse box look? you may have some corrosion in there. also you may have a bad grouund to the fuse block.

how do the lights work in the truck, kinda dim?

let us know what you find, some pics may help too, the more info you can give the more we will be able to help you.

WOO HOO!! 100th Post!

[68gmsee]

Give us a little more info about your truck.

Engine: V8 or L6?
Is it completely stock? No added stuff like electric fans, a/c, etc...
Hei or regular distributor?
External voltage regulator or has it been converted?

Here's some of the things I would check.

First and foremost, I'd make sure I have good clean ground from the battery to the block, to the cab, to the frame, and to the radiator support.

Check the cranking voltage on the battery. Meter across the poles to see how much drop you get. (Dragging starter).

Voltage to the distributor when the engine is cranking. (Starter may be draining you voltage.)

Check the fuses to make sure they're not rusted and corroded and also the wire from the ignition to the distributor.

[Naterman35]

If its HEI isnt the wire supposed to run from the dis to power with the key on?... not directly to the battery.

[billsbowtie]

i got a few mins today to look at it . so far i found the eng. was not grounded to the cab. i am working on that. and the ground from cab to frame was broken into . [i fixed that] i have checked the fuse box and it looked ok.i will post a few pic.s in a little bit. it's got a 350 eng 400 trans. thanks for the help so far.

[billsbowtie]

[billsbowtie]

[billsbowtie]

[billsbowtie]

[billsbowtie]

[mr48chev]

Ok, stock point style Delco distributor.

By the numbers=
1. what type of distributor do you have? Hei or point type?
2. If it is a point type, does it have the wire hooked up to the "R" post on the starter solenoid? The purple wire goes to the S post that is closest to the block and the yellow I believe wire goes to the R post on the outside . Some starters for 75 and later rigs with HEI don't have or need the R post and if you put one of those on your truck the resistor bypass won't work.
3. on some rigs with the resistor bypass wire they won't start when cranked if the wire isn't hooked up unless you crank them and then let off the key.
4. Assuming you have the stock distributor an coil, is there power to the coil with the key turned on?
5. If you have power when the key is on the problem lies with the resistor bypass circuit. If there is no power with the key on you will have to start tracing wires and check the ignition switch.

[billsbowtie]

it has hei dis.
the eng has about 4000 miles on it sence rebuilt it ran good the way it is. this just happen over nite. maybe the grounds not being hooked up caused this. i am still working on the the ground to the cab to eng. i havn't got that done yet.

[mclairmo]

I have seen bad (or non existent) grounds prevent the engine from starting. Also, check for corrosion on the electrical connections. Sometimes that will cause a probelm that was not there before.

[billsbowtie]

thanks guys you've all been very helpful . thats why i like this site so much. i will update this tread with what i find when i get time to work on it. thanks again bill

[billsbowtie]

heres a little update. so far i have replaced the voltage reg. & ignition switch. i also fixed the frame to cab ground & eng. to cab ground. and the battery to eng. ground was loose & i fixed it. there was a 3 wire plug unpluged under the dash near the fuse box i pluged it back up. the eng will start and run when cold now without help with the wire from dis. to bat. but if it gets warm it want start back. so i will keep looking for the prolbem. just wanted to updated the ones that was interested in this tread. bill

[68gmsee]

Thanks for the update. Looks like now you have a different problem.

Here's some questions:

If does it run good when you first crank it?
Does it fail to start everytime it gets up to warm temperature?
How long do you have to wait before it starts?

Things to check:

Insure it's not flooding on you. Check with a flashlight down the throat to see if you can see or smell fuel dripping inside.

Starter could be dragging when hot, alternator not charging, or battery may be weak.

[ll____b0t____ll]

Ide try wrapping the starter solinode and seeing if reduced heat helped it start. If so Ide get a heat shield for it and replace the wireing around starter all but the battery cable.

[mclairmo]

This is likely a new problem. Hot start problems are usually related to the starter solenoid. However, any weak electrical component will not like the heat, such as the ignition coil. Is the coil leaking oil? Is it mounted to the engine? Is it old and ratty? I would also try a new starter if it is really old. If fairly new, try the solenoid heat shield. Also, make sure battery is at least 12.6 volts when not running and over 13 volts when running.

[billsbowtie]

ok i have not had time to work on it anymore yet . but i will check these things when i get time. starter is new most of the parts are new. thanks bill

[billsbowtie]

that is the frist time it has not wanted to start when it got warm.

[El Jay]

Maybe I missed it.
How many volts do you have to the HEI, it needs 12. If you don't have that, get rid of the ballast resistor wire.

On a totally unrelated side note, get rid of that plastic fuel filter before you burn your truck to the ground.
I can just about guarantee that if that happened you would be extremely unhappy!

[billsbowtie]

i need to get a tester and check that i hav'nt gone that far yet. thanks for for the fuel filter tip.

[mclairmo]

Get a multi meter, they are very useful and usually come with an instruction manual that will teach you how to use it. Thye are good for reading volts, ohms, dwell, tach, etc.