76 international 345, ignition coil gets spark but doesn't make it to my spark plugs

[1976internat1603]

Hello! Another problem with my beautiful, stupid ******* bus. This one's a doozy, my go to mechanic friend who usually has an idea of what is going on is stumped by this one.

My engine was running fine, a bit of a power steering leak but nothing to really worry about. It's started up easily multiple times earlier in the day, but I stopped at a gas station to fule up and when I tried to start it up again, it turned over but wouldn't start. I went to check the engine and I noticed that the ignition coil is really hot! Like abnormally hot. I recently replaced my ignition coil and so I thought that was the problem, and went to the closest part store and got a new one. But after replacing it again, the engine still isnt starting.

By now I've been stuck in this gas station for hours trying to troubleshoot and eventually someone with more experience than me came along and we were able to figure out that the ignition coil is getting spark, the spark is making it to my distributor cap, but the spark plug wires are not getting spark..I replaced the cap and rotor recently and just had someone adjust the timing and look at the points, and they said they looked fine. Does anyone have an idea of where to go from here??

 

[1976internat1603]

A closer look at the distributor rotor did show that it was rubbing, and the rotor is a slightly different shape from the old one. I do still have the old rotor in cap and plan on switching those out in the morning to see if that does anything. I'll keep you updated and thanks to anyone who has advice!

 

[cadillackid]

when the distributor on mine went bad.. actually it was bad when I bought the bus.. I could tell because of how it ran on the 2700 mile drive home.. it ended up being a couple things..


1. the breaker point / coil set up just doesnt create great spark (compared to electronic ignition).. so if things werent perfect as far as clearances from cap to rotor, wires etc.. you hasd weak firing or misses


2. the bushings for the weights and springs stuck.. lot.. so the timing was always way off.. sometimes enough it didnt want to run right.. sometimes stuck in the full advance it would pop and crackle tryng to start it.


3. the bushings / shaft of the distributor itself were highly worn.. there was a lot of up / down play in the shaft as well as side to side movement of the rotor shaft.. this wreaked all kinds of havoc..


4. my points looked fine but still needed a good cleaning to actually work consistently




im assuming to check for spark you pulled the center wire off the distributor cap and held it close to a ground like the block and saw spark while cranking? spark shouldnt be continuous.. it should produce a spark with the cadence of the turnover sound...



if the spark is continuous from the coil anytime the key is on then you have a hit a points closed stopping point of the distributor when the engine stopped.. this also can account for a really hot coil. if the spark is solid even while cranking then there is a short or the points are never opening up.. and it will be a popcorn machine and will never run..



with points type ignitions it used to be an issue that you could damage the coil or condenser or points by lesving the key on with the engine off.. if the condition above was met (points closed).. those components arent meant for continuous duty.. (when the engine is spinning the coil turns on and off 8 times every rotation of the distributor)...


if everything looks normal to the center wire .. sparking to the engine crank cadence.. and not sprking continuous.. then make sure that the contact is on the wire good.. most wiresets you can slide the boot back to make sure the contacts are crimped on solidly and arent burnt... next when you plug it into the cap.. make sure the boot isnt pulled so far forward that the contact doesnt get a good connection.. you should feel the contact snap onto the cap solidly .


of course make sure your cap is seating correctly.. some caps have a "key" that fits into a slot on the distributor so its indexed correctly.. if the cap isnt seated correctly then it would be coacked slightly to wone direction and could cause rubbing or crappy spark,..



just throwing out ideas here..


once I discovered the issues in my disatributor I ended up replacing it altogether a few years ago...

 

[sportyrick]

Distributors do wear out so for piece of mind replace it .... but before up put it in get those points and condenser out of there and go with a replacement electronic ignition, so much more reliable and much hotter fire plus the timing doesn't change as the points wear out.

 

[1976internat1603]

So I replaced a lot today and nothing has worked, I replaced the cap and rotor with my old ones, but they worked fine before I replaced them, I don't think the cap is the problem, I doubt the rotor is but idk. I replaced the ignition coil last night. I replaced the condenser, and I replaced the ground wire from the negative nipple on the ignition coil to the points as that had melted a hole in the wiring from sitting on the engine. I'm still getting spark to the cap but nothing from the spark plug wires. The part store I was towed to last night doesn't have my points in stock. And I was told that I would have to redo my timing if I replaced it, and it's very complicated thing to replace because of the gap setting

 

[sportyrick]

turn the engine over with the cap off and be sure that the rotor is turning, if not them timing chain or gear bit the dust.

 

[1976internat1603]

The rotor does turn, it's in a different position each time I turn it over

 

[sportyrick]

I don't think you have to re-time it unless you have moved the distributor. A new set of points set correctly will just put you back to where the timing was when the engine was tuned up last time. I can't believe the spark is not getting out of the cap unless it's getting grounded at the rotor, all screws in the rotor correct length? That spark is going somewhere but not out the cap? As far as my experience with jumped timing chains it seems they like to do it when you turn the engine off, I wonder if you jumped your timing and the spark is just wasted between the cap terminals and jumping to the metal under the rotor.

 

[1976internat1603]

So i very recently had my timing adjusted and I think that is fine, I had a guy who works at the auto parts store I'm stuck at who seemed to know what he was talking about look at my points, and he said they are dead so that is definitely the problem, I think my grounding wire helped kill it as it did have bare metal in the middle of the wire touching the engine block...The points won't come in until Monday so I guess I have a day to explore El Centro..

 

[sportyrick]

grounding that wire will short out the points, get them red hot and melt the plastic block that rubs the points cam that creates the pattern that creates spark timing to your coil, yes you need new points.

 

[1976internat1603]

I took a quick photo while I changed the condenser

 

[sportyrick]

the rubbing block is completely gone so the points are grounding against the cams, should be some melted plastic in there somewhere. Those cams should be smooth and polished, if not the rubbing block will wear quickly and change timing, a little grease goes on the cams also, it's special points grease which you probably can't get anymore or if lucky will come with new points. As suggested, get those points and condenser out of there when you have time and a place to do it that way the points are no longer rubbing and wearing out against those cams. Petronix makes conversion kits, I don't know when IH changed dist. over to pointless ign, ask the parts guys. That would take care of a couple problems changing out the complete dist, no worn bushings, no points to wear out, worn or stuck advance weights etc. If you went with Petronix you can keep your new cap but not your rotor, if you change the whole dist your older stuff may not fit. If it was a Chevy you could go a hundred different ways but IH, not a chance, but for a while I think IH did use Delco distributors.

 

[UFO pilot]

I don't know if it has been said before, so I offer this advice because I goofed up new points on my Mopar as a young man...just a *few* short years ago........anyhoo on points ignitions do not ever leave the key in the RUN position without the engine running, if the points are closed the coil will continuously send voltage thru the points and burn them, and fast....like, under 10 seconds fast. A mechanic or informed owner could have the key in RUN for troubleshooting if needed but pull the coil wire going to the distributor so the points don't get fried, and only as long as needed.
A cruise thru summitracing.com shows lots of aftermarket parts available for International 345 V8 like electronic ignition so thats an option.

EDIT: sportyrick is right, that points rubbing block is done. The mechanic is supposed to lube the points where they touch the block with light dielectric grease, but as old as the bus is, not every past owner knew about that. An electronic ignition kit that goes into that distributor will not be bothered by that rubbing block being so worn.
Healthy distributor rubbing block example, this one is showing wear but still serviceable:

 

[Ronnie-SKO]

Just for general info a 345 uses timing gears, not a chain. Pertronics is the way to go as long as the rest of the distributor is in good shape. I have done that on a few of my Internationals. If the distributor has worn bearings, stuck weights or stuck shaft, then going to a D.U.I. distributor is also nice. I did that on one of mine, the thermostat housing does need some trimming though.



I too agree your points are done...

 

[cadillackid]

Just for general info a 345 uses timing gears, not a chain. Pertronics is the way to go as long as the rest of the distributor is in good shape. I have done that on a few of my Internationals. If the distributor has worn bearings, stuck weights or stuck shaft, then going to a D.U.I. distributor is also nice. I did that on one of mine, the thermostat housing does need some trimming though.



I too agree your points are done...

That’s why I went with a CRT distributor as it didn’t require the tstat mod.. I got the weight and spring kit so I could dial it in and use an adjustable vacuum advance ..

Have to use a new coil with pertronics and I believe you also delete the resistor wire.. (the coil I got required deleting the resistor wire)

 

[crowcreekcabin]

Points, its always points... until you put in pertronix.

POINTS... Make sure they open and close. Use a matchbook to gap them enough to get moving again. They sound like they were closed with the key on...

I fought with points for 5000 mile trip... put in pertronix and never touched them again for 5000 miles home.

POINTS. Sand them, scrape them, make sure they open and close, limp home but replace them and/or get pertronix. You will not regret. Starts better, never needs adjustment and runs better... more power, smoother...

Points... did I mention points?...