Engine Won't Start

[The_Handier_Man1]

From  Supplysunshine1 (Original Message)
Sent: 3/2/2005 3:05 PM

We have just purchased a 1974 Brave Winnebago with a 318 motor. We drove it home which was a distance of around eighty miles. We have not been able to get it to start. I checked the starter and it is firing.Do you know of anything else we could try.

Thanks

Don



From: nvdesertrat0775
Sent: 3/2/2005 4:04 PM

What happens when you turn the key?  Does it click or make any noise?  The ignition switch could be bad.  If you leave the key on and short across the starter posts, will it start?
  If you could give a little more detail about what happens when you try to start it, maybe we could make better guesses :>)
  It COULD be:  Bad ignition switch; loose ground; broken wiring; faulty starter, just to name a few.

Another possibility if it seems everything is trying but it just won't start, is the ignition coil.  Do you know if it's electronic or not?  Also, are the battery terminals clean and making good connection?  Maybe the battery itself is dead... can you hook another one up and try it?

p.s....  congrats on your new family member!

Rat



From: Liv42dayOK
Sent: 3/2/2005 4:22 PM

Good to have you aboard,

You will find a wealth of possible causes/cures using the Message Search and the key word "start".  Also, please read the Posting Guidlines on the Message Board Home Page.  - Sob



From: denison
Sent: 3/2/2005 6:41 PM

Yes, tell us what it does do, in very basic terms. If it ran for 80 miles, we should be able to assume it is getting fuel and ignition.
You said you checked the starter, and it is firing. Did you do that by shorting the large terminal on the starter to the small terminal?
When you turn the key, does the starter make the engine crank around at all?
If it doesn’t, then while holding the key in the â€"start- position, pull the shift lever from park, down slowly into drive, and see if the starter begins to turn the engine. There is a neutral/safety switch on the transmission, to prevent the engine from starting when it is in gear. The shift linkage could be out of adjustment or stiff, and that switch might not close. It could also have a loose/dirty connector, or just be a bad switch - from old age.
If the starter doesn’t turn when you try the above, it could be a bad fuse, or a bad starting relay (which is not part of the starter). On my 72 Winny, the fuse for the backup lights and the horns also feeds that neutral/safety switch. If my backup lights don’t work, its likely that fuse is blown, and the starter wont work either. But if the engine were already running when the fuse blew, the starter would then not work when you turned the ignition key to the start position. The starter Would Work though, if you lay underneath the RV and shorted the big terminal on the starter to the small terminal. Since this defeats the safety feature -of not starting when in gear-, be SUPER CAREFUL you don’t get run over if it starts.
If the starter cranks the engine but the engine wont run, check whether the choke on top of the carburetors is in the full open position. In this case you would be able to get it at least fire a couple of time by pumping the gas pedal 3 or 4 times in between starting attempts, or pushing the choke plate almost shut. And if the air cleaner is off, and the choke held open, then when as you push the accelerator down, you should see gasoline squirt into both of the primary throttle throats; the ones which have the choke above them. If it doesnt it could be fuel starvation, from a clogged filter, or a gummed up needle vavle going into the float chamber.
If it cranks and starts, but shuts off as soon as you let the key turn back to the â€"run- position, that’s not unusual, and we can tell you how to seek out that problem.
You can check the health of the electrical circuits and battery by turning on the headlamps. They should be nice and bright, and should only dim slightly when the starter is turning.



From: Supplysunshine1
Sent: 3/2/2005 7:55 PM

the starter will turn if you jump from big bolt tosmall bolt.
starter willturn if you jump from big bolt to small boat on starter relaywhich is mounted on drivers side chassie.
When turn switch on it does not make any  noises
Can not find no blown fuses in fuse box under dash
Electronic ignition seems to have leaked a clear substanc on bell housing
Interior light work fine
Dsah lights does not work
Generator runs
Stove exhaust fan works
Bathroom fan does not
Switch at the door what does it suppose to do

Thanks
Don



From: nvdesertrat0775
Sent: 3/2/2005 10:55 PM

Did the dash lights work when you drove it? [I'm still thinking "Ignition fuse", on the principle of 'easiest, cheapest, quickest to replace' things first...]  If you have aligator clips handy, you might bypass the fuse -only long enough to test the ignition key- since I'm not sure if you tested the fuses or only 'looked' at them.
  But frankly, if it looks like ANYTHING has leaked out of the Electronic Ignition, my first move would be to replace the unit.  Even if that's not the cause of the starting problem, that can't be a good sign, lol.
   Seems to me you've eliminated the battery itself, and the charge on it, along with the starter unit.  The safety switch denison mentioned is a good possibility, but I'm not sure how you could test it.  The ignition switch is a smaller possibility, as is the wiring [always possible]  But I'm inclined to think it's probably that electronic ignition unit.
  With stuff leaking from it, I'd toss it w/o another thought, but if you want to put a multimeter on the battery input to it [or even a 12v bulb with positive and negative wires connected] and see if the voltage is getting to it when the key is turned, that might be worth trying.  If it's getting more or less 12v to it's positive terminal, but NOT to the starter, it's probably {note: "Probably!"} the culprit.   But remember, this is being done sight unseen, from a distance, and carries absopositivelutely no guarentee!  Good luck with it, anyway!



From: Slantsixness
Sent: 3/3/2005 7:43 AM

Don,

here's a few things you can try:

Check the supply wire to the steering column (red) (comes from the battery, not the fuse box).
Neutral safety switch? on the drivers side of the transmission. also try the shift lever, just in case it got stuck, try starting in "neutral". short the center pin to one of the outer pins, if the reverse lights come on, use the other outer pin and try to start!
Dead chassis battery? (hit the MOM switch (dash) and try it again?) (in this case check your alternator when you get it running)
Chassis switch off/bad? (some class A's behind the driver seat to the right in the floor right by the fuel lever)
Starter solenoid bad/loose connection/corroded connections? look for a brown wire going to the starter, usually the culprit. (check by shorting the bolt terminal to the screw terminal below it, which is the brown start wire)
Bad starter (you can check this by shorting the small terminal to the large terminal, it  should crank, if it does look,at #4 above!)
Bab wiring at the steering colomn junction. It is yellowed white plastic (3" long, and flat), and if it's bad, you'll see a burn mark in the plastic.
your dash lights may be a bad light switch, or just all burned out! they're pretty old, and not very bright to begin with. If the running lights outside work, then you should have voltage. Look for orange wires behind the dash panel and check for voltage. Alternatively, it may be related to #7 above, check the pink wire for voltage (sometimes it's a blue wire instead!)
And last but not least, check the AMP guage for burned connections. this is common in Dodge chassis when too much current is drained from the chassis circuits.
In any case, when you get it back running, check your alternator and regulator, sounds like they might have caused your present dilemma.
The conformal coating leaking out of the ignition module is a nusiance, but rarely results in a failed module. this rubbery crap just deteriorates over time, and slowly turns into a sticky goo. It is not likely to be bad, but you might want to replace it just because of the sticky mess!

I hope this has been helpful!

Slantsixness (Tom)



From: nvdesertrat0775
Sent: 3/3/2005 12:48 PM

The conformal coating leaking out of the ignition module is a nusiance, but rarely results in a failed module. this rubbery crap just deteriorates over time, and slowly turns into a sticky goo. It is not likely to be bad, but you might want to replace it just because of the sticky mess! <

Wow!  I never knew that!  Guess we're never too old to learn, huh?  Thanks, Tom!

Rat



From: Im-still-Lefty
Sent: 3/4/2005 2:46 AM

RE: Coating deterioration on ignition module. Tom, While I have seen a
couple of ignition modules that have had the coating fail and the module
still worked, the vast majority have been bad. From what I've seen, the
coating only fails and runs out after the module overheats. If the coating
has ran out of the back of the module, usually it is a sure sign of a
failed,(or failing) module, and needs replacing. Just my opinion, Lefty



From: HeavyHaulTrucker
Sent: 3/5/2005 12:09 AM

Yep, it has been my experience that they don't even need to melt to fail! 

Seriously though, my money is riding on a failed (shorted) ignition module that caused the fusible link to blow.  The clues are all there -- and no power to the key is an almost universal sign that the fusible link is gone.

John



From: Slantsixness
Sent: 3/6/2005 8:33 PM

Heat, and overheating of the ignition module do NOT cause the conformal coating to break down. It is rather a time issue and exposure to exhaust gasses and fuel vapor that cuse it to turn to goo. and a non conductive goo, too....provided your ignition module isn't soaking in oil!

The heat sink on the ignition transistor is more than ample enought for the load on the transistor. There is only a small handfull of other parts in the thing anyway, and they don't develop heat themselves.

The conformal coating (the jello stuff) has absolutely nothing whatsoever to do with thermal transfer in the ignition module. This same "jello" is also in the regulator.

If you have a failed module, and failed because it is overheating, you either have a lack of cooling across the module heat sink(this is common when the fiberglass batting falls in front of it off the dogbox cover, preventing any airflow), a bad coil capacitor(yes you are supposed to have one!), a defective coil, or an excessively high charge voltage (like 18-20 V out of the alternator and on the system) and finally...
Running without the ballast resistors!

The ignition module itself is darn near bulletproof. Probably the best ignition system anyone ever made (yeah, and MoPar canned it for the ESC system...why? heck if I know!). It gets a bad rap though, when people put them in extreme circumstances. Mopar actually made 6 or 7 versions of the module, and they ARE different! Unfortunately, most Auto parts stores carry the -2 version, that is, in fact, for the slant six, although it will work for any application, it has a lower power rating, and the lack of 1 terminal connection. The -6 (the "gold" box in the blue case '78-'85) with ALL 5 wire tabs in place is the only one suitable for V8's and it doesn't even matter which V8, since all it does is pulse an ignition signal (from the distributor pickup) to the coil primary, and that's more than necessary.

So.... there's my 2 cents.

Tom



From: Slantsixness
Sent: 3/6/2005 8:37 PM

Oh.....and I'm not trying to start an argument here...
It's just my opinion and I'm sticking with it!



From: mightybooboo
Sent: 3/7/2005 1:14 PM

So all the ignition module is is a set of electronic points(essentially)? I  understand we still have the pickup in the distributor.

BooBoo



From: daved27c
Sent: 3/8/2005 3:21 PM

Don;

I actually had the plug on the back of the Ign. switch vibrate partally off. It caused the same starting problems you describe.

Dave



From: Supplysunshine1
Sent: 3/8/2005 10:33 PM

Thanks for the inf. We had found the peoblem, so it is now running but we seem to think that maybe the carbuator needs t0 be replaced, what is your take on that. the carbuator when you take off in it ,it does not want to take the gas. 

Thanks

Don