78 Midget won't start

[Sl1m]

Hey guys,

My buddy and I are working on his 1978 Midget and we're having some trouble diagnosing the problem. It's been sitting for years and up until this point was only started up maybe twice a year. It was originally having problems starting, but eventually would. The idle was rough and it would often die at low RPM. After shutting the car down, it wouldn't restart until it sat for a while.

We finally got around to digging into it, and trying to get things sorted. The first thing we did was pull the carb (as it was leaking) and rebuilt it. We took the cap off the distributor, to check it out, and put that back on. After reinstalling the carb, the engine wouldn't start at all.

It seems to be having trouble cranking where it'll crank for a few seconds, the cut out on its own. I'm not sure if this is a separate issue as to why it won't run, or one in the same.

That aside, after cranking on it several times, we started checking the basics... Fuel is not the issue. We're getting fuel to the carb, and through the carb. At the same time, we're getting spark to all the plugs. For some reason it's not even giving the weakest attempt to run.

We also checked to make sure none of the valves were sticking (and they weren't).

I'm lost as to where to go next... I'm planning on checking compression tomorrow, could that cause it to completely not start? If so, why would it run (well, intermittently at least) before removing the carb, but not now. It would have had to have compression before to run, but now it's not...? Any suggestions?

Thanks in advance.
Dennis

 

[tdskip]

Good morning Dennis - and welcome.

There could be many things happening here, so best to be methodical in running them down one at a time. I apologize if you are well past these suggestions, but fuel/air/spark in the right combination is probably a good place to start.

Seeing that you have fuel to carbs, when you rebuilt the carbs was the initial mixture set correctly? Does trying to starter her with / without the choke make a difference? Any vacuum leaks that you may not have run down maybe?

Seeing that you have spark at the plugs is the timing correct? Did you confirm the static timing is bang on? Are the plugs clean and gapped correctly (probably not <span style="font-weight: bold">the</span> issue but good to check anyway.

Others will jump in with additional ideas.

Hang in there.

 

[JPSmit]

Hey guys,

We took the cap off the distributor, to check it out, and put that back on. After reinstalling the carb, the engine wouldn't start at all.

sounds very much like you have the plug wires out of order, don't ask me how I know

 

[tdskip]

Hey guys,

We took the cap off the distributor, to check it out, and put that back on. After reinstalling the carb, the engine wouldn't start at all.

sounds very much like you have the plug wires out of order, don't ask me how I know

LOL - yeah, I can confirm from personal experience as well that in correct order would keep it from running properly.

 

[Guest]

+1

It's easy to mix things up

Make sure you have the rotor and cap on right and locked in.

 

[toysrrus]

Howdy Folks,

Happy "Post" Thanksgiving,

Have you tried using jumper cables? Is your battery putting out 12volts? You may want to check or swap the coil. You may also want to check that the wire going into the Generator (If thats what you have) is connected. I had a Yellow & Green wire & did`nt know where the heck it came from or was supposed to be connected until; "No Turning over the engine"!!

Russ

 

[Sl1m]

Thanks for all the replies so quick...

A lot of your suggestions are going to be helpful, but the thing I keep asking myself is, if that could possibly be the case, why was it running before rebuilding the carb? Although running rough, it was running (intermittently)... which leads me to believe it's not the fire order (as it hasn't been changed since) along with wiring, coil, etc.

The battery has been changed/charged. We did everything we could to insure we were getting power. The carb is pumping fuel into the engine, although a mixture issue could be part of the problem. I'm not sure where exactly to set the adjustment screws to have them at a reasonable spot for the initial start up (before tuning). And I'm 100% sure there is sufficient spark to the plugs.

As for vacuum, we hooked everything back up just as it was before the carb rebuild... It SHOULD at least do what it was before, where it would start and run rough, right? I don't see a reason it wouldn't. The timing is not spot on, but like I said, it started and ran (rough) before removing the carb.

I checked compression, and the 1st cylinder only made it to 90... but the rest were fine. Could this, along with poor air/fuel mixture cause it not to start all together now? I found my notes from the last compression test about a year ago, and the 1st cylinder was low then too, but it would still run. The fact that it ran before, and now isn't is what has me stumped.

Any suggestions would help, but keep in mind I've made it through most of the basics. If someone would suggest where to have the adjustment screws on the rebuilt carb for the initially start up, it would really help.

Thanks again,
Dennis

 

[Trevor Jessie]

By any chance did you put the top of the carb on "backwards" and thus blocking the vacuum port?

 

[SilentUnicorn]

https://www.bmcno.org/tech%20tips/zenith%20stromberg%20tech%20tips.htm

 

[Guest]

shoot some ether to it and see what happens.

 

[Guest]

Hey guys,

My buddy and I are working on his 1978 Midget Dennis

I found my notes from the last compression test about a year ago,Thanks again,
Dennis

Friend ehh?????

...so, you kept notes on your "friends car" from a year ago?!?!?!?!?!......


BUSTED !!!!!

hmmmmmm, tell your "friend" don't worry, we'll help "him" get it straight !!!!

hehehehe, sorry, I just couldn't resist.

Hang in there bro and welcome !!!! :thumbsup:

 

[Sl1m]

Believe it or not, I've had the same friend for more than 1 year lol... but that's beside the point.

We went out there today and got the rough cranking issue fixed. Got a better ground which seemed to fix that. It still won't fire though. Checked over everything that was suggested and still haven't got anywhere.

I pulled one of the plugs after we had been cranking on it for a while and it was pretty wet. We're still getting spark, but I'm starting to wonder if the carb (for some reason) is dumping too much gas into the chambers. I tightened up the adjustment screws to where it should be letting the least amount of fuel in, but we're still getting nothing. It's not even popping.

More suggestions would be helpful.

 

[Jim_Gruber]

Try replacing the plugs so you've got a known good value to start with. Wet and fouled plugs make it very difficult to start. Time to spend $8.00 at local parts store.

 

[Jim_Gruber]

Try replacing the plugs so you've got a known good value to start with. Wet and fouled plugs make it very difficult to start. Time to spend $8.00 at local parts store. Be sure to recheck the points and make sure they aren't burnt. I had similar issues with Bugsy my '68 and it ended up being a crap condenser.
Plugs were getting an very, very weak spark and since I had just replaced the points & I didn't suspect that as a problem.

 

[RickB]

As my friend BillM suggests a lot - and he knows - take a plug wire directly to the coil and try firing it up. It should fire on one cylinder at least. If not then work that direction, if yet then work the other way.

And like I always say, starting fluid is your friend...

:wink:

 

[bthompson]

More than likely the Zenith is running rich. Ask any of us who own a 1500 Midget--we'll all tell ya the same. If you have the automatic choke version, it's almost assured. If you have timing and spark, with wet plugs and no start, it sounds like you're dumping too much fuel in the cylinders for it to fire. <span style="font-style: italic">Memorize</span> that John Twist article referenced earlier: it will be your best friend.

A few things to look for, from personal experience:

--Are you running with the original air filter box? Is the filter clean? (A "free-flow" filter will <span style="font-style: italic">really</span> screw with the mix.)

--Is your float porous? Is the float needle sticking and flooding out?

--Is the diaphragm torn? Seated properly? Oil in the dashpot?

--Is your metering needle properly seated in the piston? Is it adjusted to its lowest (leanest) position?

--Is your choke broken? (You can blank it off if you aren't sure and take it out of the equasion)

and finally...
--Make sure you have NO air leaks at any point, period. Zeniths are so darn sensitive to air leaks, and <span style="font-style: italic">any</span> leak will drive it richer.

"The idle was rough and it would often die at low RPM. After shutting the car down, it wouldn't restart until it sat for a while...After reinstalling the carb, the engine wouldn't start at all."

That sounds like classic rich running to me. Remember that "most carb problems are electrical," but if you're certain your spark is proper, the mix is the only thing left.

If you're like the rest of us 1500 owners, you'll fiddle and futz with it, get it mostly running, try to finesse the last bit out of it, and eventually throw it across the room and get an SU or Weber. (Hold out for the SU!)

 

[JPSmit]

couple of things.

1. no points - it's an electronic ignition.
2. I am assured that floats in ZS's rarely go porous - to the point of arguing with my parts guy cause he didn't want to sell me new floats.

Let's go back,

what do we know?

1. carb rebuilt
2. dizzy cap taken off
3. plugs wet.

1. it's getting fuel
2. yes, time to spend $ 8 for new plugs.
3. before I poured more gas in, I'd try and see what happens with starter fluid.

BUT,

I'm still betting on electrical. here's why.

1. it's not even trying to start, If it were at the carb, I think it would try to start some, even chug a little.

2. Nothing else but the cap has been touched, therefore, not likely coil etc.

I will be the first to admit that there has been at least one occasion where I was ready to bet money that I had put the wires back in order but they were out of order. personally, I think a MOWOG did it but that's another story.

one thing at a time.

1. Did the cap go on 180 deg out?
2. Are you certain - to the point of checking that the wires are correct
3. is the rotor in? does it work?
4. you tell us you are getting spark, but, did the dizzy get moved? is the bolt tight.

I really feel like this is where we need to start to look but, assume nothing. Check, double check and recheck. In my experience, it is more likely something simple and obvious that has been overlooked.

 

[tdskip]

I agree. If the carb were overly rich I'd think if nyou let it sit overnight and then tried new in the AM you'd get at least some combustion, no?

 

[Guest]

couple of things.

2. I am assured that floats in ZS's rarely go porous - to the point of arguing with my parts guy cause he didn't want to sell me new floats.

Get a float scale if you're ever in doubt.

You probably can't find one nowadays but in a "head" shop. (read "weed head")

Same scale used for both floats and weed. Just might not want to keep in it the glove box cause you might have some 'splanin' to do to da blue man.

 

[Guest]

I agree. If the carb were overly rich I'd think if nyou let it sit overnight and then tried new in the AM you'd get at least some combustion, no?

Yes and no. If the float is bad or hung and it's dumping fuel into the motor, letting it sit might not make a difference. If pistons are dished, fuel is still liable to be in too large a quanity AND, the oil film on the rings is now gone, lowering compression even further.

Factor in that the car has been setting for some time and....


NOw this I say if...and only IF the above has happened.

Drag the car in gear with the plugs out. This will assure all fuel is out and the rings are seeing oil. Granted, this is not "professional" but it works. This will not help an iginition problem (other than the fact no voltage drop due to starter) Make sure you cut off fuel or fix the problem first.

I'd recheck all ignition first and buy new plugs. Check the oil too and see if it smells like gas. If it does CHANGE IT !!! (but make sure you fix fuel prob first.)

I'm with JP.



Hey, how old is said fuel????