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Hard starting backfire

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Monster

Hard starting backfire

#1

Post by Monster » Thu Feb 03, 2005 1:34 pm

Please tell me common symptoms so I can begin diagnosing a new problem:
Backfires once on fire-up. Usually starts on one or two, but now it's four or five. Just pressure tested and sealed manifold. Seems to have started doing this since I washed it last? Any help would be appreciated...
M.



Skip
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Re: Hard starting backfire

#2

Post by Skip » Thu Feb 03, 2005 10:09 pm

Coil get wet...battery not fully charged...fouled or fouling plug...carb too lean...plug wires going bad...those are some of the things I went through....Skip

57pan
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Re: Hard starting backfire

#3

Post by 57pan » Fri Feb 04, 2005 9:29 am

What kind of circuit breaker do you have? Single points? Dual points? (One set of points is bad?) Auto-advance? (Stuck in 'advanced' position?) Leaking head gasket? Burnt valve? Misadjusted valves?

Guest

Re: Hard starting backfire

#4

Post by Guest » Fri Feb 04, 2005 10:29 pm

Post by Monster

Timing is bang on, single point manual. Started everything off by ensuring I'm airtight. Battery is a few years old, so seeing their only $20.00 here, I'm getting a new one for the hell of it. Also have spark plug wire at home, gonna make new ones tonight. I'm starting to think that shitty gas station I had to fill up at last had something to do with it? Might as well pull the pushrod tubes and have a look there while I'm at it. Still doesn't explain why it all began to go sideways after I washed it. I was careful not to drench it too. I'm sure it's electrical somewhere. Or am I? G-damn this pisses me off.
M.

Skip
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Re: Hard starting backfire

#5

Post by Skip » Sun Feb 06, 2005 4:12 pm

Shit I drown mine everytime I wash it...just like rain riding...bad gas will surely have something to do with it...try draining it out of carb and tank and start fresh...that may be the easiest fix....maybe add some MMO or other additive of your choice............Skip

Cotten
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Re: Hard starting backfire

#6

Post by Cotten » Sun Feb 06, 2005 9:23 pm

Coils can be very sensitive to water.

....Cotten

Monster

Re: Hard starting backfire

#7

Post by Monster » Mon Feb 07, 2005 6:08 pm

Here's what I've tried:
Battery tested, it's charged to 12.4V. Spark plugs were pulled; they aren't fouled and when kicked, the spark was blue with a BIT of orange in it. I popped off circuit breaker cover and rolled it until points were closed. Turned on ignition and broke the points: hardly any spark at all, sometimes couldn't even get a spark when breaking the points repeatedly. Now I'm thinking maybe shitty condenser? I've got a multi meter, but am no electrician. I would like to test coil, but am not too clear on that either. I put it on it's lowest ohm setting and crossed the two terminals for a reading of 1.5? I could be doing something wrong there, but just thought I'd throw that in anyway for all you wiring nuts, can ya tell I'm trying everything?
Whaddya think?
I'm buying a new condenser on my coffee break tommorrow and giving it a whirl. Hoping it aint a coil? One thing at a time I guess...
M.

Well, it ain't the condenser. I'm gonna borrow a coil off a buddy and try that now. The shitty part is it's sunny'r than hell and I am not riding!
M.

Skip
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Re: Hard starting backfire

#8

Post by Skip » Tue Feb 08, 2005 2:32 pm

you know, that sounds a lot like what I went through a couple of months ago...had the same problem, only mine only started once for about 30 seconds, then nothing but spitting out the carb, etc...new points, plugs wires, condersor, coil, and battery....still the same thing...nothing...I readjusted my push rods to a very sloppy spin...and now life is good with about 350 miles on a new top end...just a thought....Skip

fourthgear
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Re: Hard starting backfire

#9

Post by fourthgear » Tue Feb 08, 2005 7:51 pm

Washing it just may have been a coincident, but water can get into the oddest places and screw with your mind .Did you change the plugs ? I use a spray called STRIKE HOLD,www.888knivesrus.com. If you ever watched the demo on this stuff , you would not believe your eyes as far as water proofing electrical term. and other things . he sprayed a 115Volt screw in light fixture and put it under water and put the bulb in it,under water and turned it on and yes it worked , then did it over and over again and it worked every time with out shorting out , (I know because we provided them with a breaker-ed power strip). he had light switches and breakers working under water , I almost couldn't believe my eyes.They said the Military is using it .

jack moghrabi
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Re: Hard starting backfire

#10

Post by jack moghrabi » Thu Feb 10, 2005 6:12 am

Hey Monster,

As I read your post on your latest test, you indicate that your are getting spark at both plugs (blue spark with some orange in it) and that following that you were getting nothing at the points.
Well, to me that sounds like an intermittent spark problem. Sometimes yes and sometimes no and frustration on your end--totally. I know a bad coil can do that and also a fault somewhere in the wiring and I suppose a bad condenser could be intermittent too (but my guess is that a condenser either does it or simply doesn't do it.....).
I would first make sure the wiring is not at fault. If you do have an intermittent spark problem you should definitely see no fire at the plugs sooner or later given enough cranks.JackMO

Monster

Re: Hard starting backfire

#11

Post by Monster » Thu Feb 10, 2005 5:52 pm

Still sunny, and still no riding. Now I've replaced the plugs and wires, rechecked the timing, changed the gas to stuff I know is good, and adjusted pushrods to a nice loosish spin. My battery is fully charged as well. It struck me as odd that all pushrods needed loosening, all four were definately tight, yet it was running great before this. Now, I can't even get the backfire, and what I'm getting after kicking my freakin ass off, is a big COUGH through the carb and a puff of white smoke. I pulled the plugs, they're soaking wet after the kicking, and looked through the carb, it's wet too.
I wired it myself, and took extra care heat shrinking connections etc. It has been trouble free for 10,000 miles. I know my wiring like the back of my hand, but am an idiot when it comes to my multi meter. Can someone tell me how to check for continuity so maybe I can run through things to see if something is shitty? ( I know, dumb question, but it's a feature I've never tried before)
I've trouble shot a few repairs before, and am no stranger to my wrenches, but the coughing and white puffs from the carb, and the tight (couldn't even spin-em) pushrods are worrying me. What-the-f?
Mstr.
I am open to any suggestions?

fourthgear
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Re: Hard starting backfire

#12

Post by fourthgear » Fri Feb 11, 2005 4:33 am

monster
I had a manual adv. circuit breaker ( distributor ) That every time I moved it , it was went out of time . The top of the dist. where it turns , was egg shaped and would give diff. timing every time I would move it to start and was hell to start and would start OK some of the time . It seemed to start doing this out of the blue .The way I checked it was to put a static timing light on ,timed it and moved it back and forth to see if it would light the light every time I put it to full adv. and of course it did only about one out of twenty times , so after replacing with a re pop auto adv. dist. it was a beautiful thing with normal starting after changing it out . I'm not saying you have the same problem but, some thing to check.
To check continuity , your multi meter will have a symbol that looks like a horse shoe or it may have a OHM setting or a couple of diff. ranges of settings and some like the one I have in front of me (Digital FLUKE Meter ) may even have a audible sound for continuity also. best way to test a component is for it to be completely disconnected (unwired ) One lead at each end of course and it will give a reading or if you have an analog meter the needle pointer will show a specific reading or show" INFINITY " which is total continuity.
Since your problem started with a wetting I would check your coil to see if its open or grounded. Disconnect the two primary coil wires (points and batt. wires to the coil) and put one lead on each post or terminal and see what it reads , if you don't get a reading , its a open coil and not good , if you get some thing like (example )4.5 ohms , your primary coil is OK, to check to see if its shorted or grounded , with your plug wires removed from coil , take one lead from one of the primary posts or term. and touch the other lead to each of the secondary coil term. ( where the plug wires plug into the coil) to see if there is continuity , and do the same for the other primary term. or post to each of the secondary term. ( where the plug wires go in the coil ) If you have continuity between any term. of the primary and secondary coils , you have a shorted coil internally and it does happen. Another thing to check is to see if the coil is grounded , to do that test ,just check each term. you just did individually from term. to any good ground on the frame. There should be no continuity between any coil term. and frame . I have tested a lot of coils and I have got so many diff. readings as far what is published for specs , that I have come up with, when in doubt , throw it out , mentality. You can also check for grounded wires in the same way, with wire disconnected at both ends , test ether end to frame to see if it has continuity and if so , its grounded.To see if wire is good (continuity) just put one lead at each end to see if its open (no continuity ) or good ( continuity ) Long winded I know , I tried to be basic. Hope it helps ya.

Monster

Re: Hard starting backfire

#13

Post by Monster » Fri Feb 11, 2005 5:03 pm

Fourthgear,
Thanks, and yes, being basic for me was very helpful. It turns out in the end it was a bad coil! I broke down and had a friend come help diagnose. I felt good at least that he had tried all the same things I did and that I was correct on everything as far as timing, lifters, manifold, points etc. After all was said and done we tried another coil and voila- problem solved. Must have been an intermittent thing cause I pulled plugs and kicked to see spark, but I guess not enough to run it or maybe only one cylinder? Anyway, I am happy now that new coil is on the way and I still have months of sunny weather ahead of me.
PS Did I say how much I hate electrical shit that I can't see? At least with mechanical stuff you know what you're up against. Thanks to everyone for your help, I hope someone else benefits from my past problems and all your kind support by reading this post.
Monster.

fourthgear
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Re: Hard starting backfire

#14

Post by fourthgear » Fri Feb 11, 2005 10:41 pm

Thats cool , did you test the coil for practice, curiosity?( Ain't electrical fun !)

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