Jump to content

Recommended Posts

I have another fun issue

So after finally getting my corolla running, of course I was going to take it for a lap of the block, even if it isnt 100% legal

however, after feeling it hesitate under throtlle I double checked and reset the timing to TDC at 8deg, realised my firing order was off as well.
Thought no worries, switch it to 1342 which is standard firing order, this is where my problem starts.

when set to 1342, it wont fire, it'll have a little pop like a weak backfire through the exhaust once every few seconds, but if the firing order is set to 1234 it'll run and idle, but rough as guts

If i pull leads while its idling to see if it runs or dies, no matter which firing order its in, no matter which plug i pull it makes no difference, except for cyl 3
Cyl 3 will always kill the motor on any firing order no matter which lead from the dizzy is going to it

 

Any help or ideas on whats going on?

Link to comment
Share on other sites

Members dont see this ad

Which way does the rotor turn??

How do you determine which is cyl 1 TDC?

I don't think your firing order was wrong to start with, it just wouldn't run if it was wrong.

If cyl 3 kills it, that's the one that is running best.

I've seen people with the wrong firing order, people thinking the dizzy rotates the other way, people setting timing on the wrong side of the dizzy lobe, people picking cyl 4 as cyl 1 and probably a few more ways to make a mistake,

Edited by altezzaclub
Link to comment
Share on other sites

Are we to assume that the dizzy has not been removed from the engine, or put back correctly ?  Hardest part is getting the dizzy back in, & lining it up with the oil pump & making sure the rotor points to a HT cap connection.

Quick mans dizzy insertion.

Line up the mark (indent) on the crankshaft pulley with 10 deg (BTDC) mark on the camshaft chain cover.  Don't worry whether it is no: 1 or no: 4 cylinder TDC.  It must be one of them, so there is a 50% chance of getting it right the first time. 

Insert the distributor so that the vacuum advance bellows is facing the front of the engine, & the longest part of the distributor lies fairly parallel to the side of the engine.  Check now that the rotor points to one of the caps HT lead points. (doesn't matter which one). If it doesn't line up, remove dizzy, turn rotor slightly & reinsert, until the rotor lines up with a HT lead point.

Adjust the points using trouble lamp or bulb method.

Connect spark lead no: 1 to the dizzy cap to which the rotor is pointing. Connect the remaining 3 leads in a clockwise rotation, to spark plugs 3, 4, & 2.

Start engine.  If it doesn't start, or back fires badly, after 2 or 3 tries, then swap leads 1 & 4 with each other, & 2 & 3 with each other.

Start engine !  Guaranteed to work, everything else being equal/OK.  You can always fine tune it afterwards, but this simple & quick procedure will get you started quick time.

Cheers Banjo

   

Edited by Banjo
Link to comment
Share on other sites

Its an electronic dizzy from a 5k 

To find TDC I took the spark plug out of cyl 1, and jabbed the ignition and watched to see when a mist of fuel shot out, that way I knew it wasn't far from TDC and it was on the compression stroke
From there I adjusted the crank pulley to 8deg and put a feeler down the spark hole to see where the proper TDC was.
Had the distributor out so I dropped that back in and then adjusted that via the oil pump drive slot to make sure the rotor button was dead on cyl 1 in the cap when it was TDC on cyl 1

The firing order if I have it set to 1234 and then set 2/3 reverse so it 1324 I get backfires through the carbs.
1342 it hiccups and then 1234 or 4321 and it'll run but sound like its skipping 
I always use cyl one as the closest to the radiator/furthest from the firewall 
 

Link to comment
Share on other sites

1342 is the only one that will work, the hiccup is timing not right.

Really, you need a timing light, the only way to sort it quickly and easily.

If not, then take out the oil cap and watch a valve on #1 cyl as you turn the crank with a spanner. That will let you work out if it is #1 or #4 that is coming up to TDC. I expect your timing is close enough for you to see that anyway.

Put the crank on 8deg BTDC and take out #1 spark plug, leave it on its lead and lie it on the head so it earths out. Turn the dizzy clockwise a little then back, and as you go over the firing point the spark plug should fire. Get it so it has just fired as you turn anticlockwise and lock it there.

 

Link to comment
Share on other sites

Hi Ethan,

                Are you sure the dizzy is working properly ?  Reluctor type dizzies, could be giving you these problems.  Is your dizzy one with the internal ignitor, or an external ignitor ?

When you say . . . .

Quote

So after finally getting my corolla running, of course I was going to take it for a lap of the block, even if it isnt 100% legal

Does that mean you've had the engine out, or heads off etc. ?

Cheers Banjo

Edited by Banjo
Link to comment
Share on other sites

Altezzaclub,

so you're saying that if its at 8deg and its TDC on cyl one then I should have it 8deg before that, so like 16deg on the crank? then turn the dizzy clockwise to see when the spark strikes. From there would I tighten the dizzy down so that as the spark fires the rotor is dead on cyl#1 and then make sure its TDC or 8deg BTDC? I think I'm understanding what you're saying and apologies if I'm not aha
 

 

 

Banjo,

no idea if its a reluctor type dizzy, but I do know it does have an internal ignitor, found that one out when I had and external module on it as well and got no spark for a while haha

Quote

Does that mean you've had the engine out, or heads off etc. ?


Nah engine has stayed put in there and no heads have come off, outside of the dizzy, intake manifold and exhaust headers the engine hasn't come apart because not going to lie, definitely not in my skill set to do haha

 

Link to comment
Share on other sites

No, once you're sure its #1 cyl coming up to firing on TDC, just put the crank on 8deg BTDC and work with that. I think you can see the inlet valve through the oil filler hole, the exhaust rocker is too far forward.  So as the crank timing mark comes through the last 90deg before TDC the inlet rocker should be stationary.  If the inlet rocker is coming up (closing the valve) then its #4 that is firing at that TDC & you have to turn the motor over one more turn.

With the crank pulley on 8deg BTDC, you now want to fire the spark plug. If its like my 5K dizzy, there are 4 little extensions on the dizzy shaft that replace the 4 corners on the old system. One of these extensions will wipe past the electronic pickup to fire the coil. The easiest, now I think of it, is to turn the dizzy so that extension aims straight at the metal bar in the electronic pickup.  If the vac advance unit hits the head then you'll have to take the dizzy out and move it a tooth.

While that's not quite as accurate as having it fire the spark plug, the amount it is out is not worth worrying about. After that you just tighten the dizzy and make sure the rotor points to #1 plug lead. Clockwise they will be #3, #4, and #2 from there.

 

Electronic pickup.jpg

Link to comment
Share on other sites

Ok so I double checked everything, watched the inlet rocker for cyl one and it sat stationary for the last 90deg or rotation before it hit TDC on the timing mark at 8deg BTDC
That was dead on so I knew TDC was right, took the dizzy cap off and  looked for the point under the rotor, that was dead in line with the metal bar on the pickup.

With all that checked and accounted for realistically it should fire up and run no sweat, so I don't know where its missing or going wrong here, spark seems good across all cylinders. 
If theres any other info you guys need let me know so I can get this thing sorted and keep getting it closer to on the road 

Link to comment
Share on other sites

Ok, that sounds like the timing is sorted out...

Time for a compression test!  Any idea of cyl pressures?  I'm thinking of this-

Quote

If i pull leads while its idling to see if it runs or dies, no matter which firing order its in, no matter which plug i pull it makes no difference, except for cyl 3
Cyl 3 will always kill the motor on any firing order no matter which lead from the dizzy is going to it

That says that cyl 3 is doing all the work. If they all have spark at the right time, is it the only cyl with good compression??

Link to comment
Share on other sites

I have a set of verniers my grandfather that are from Japan and they're the greatest things!

Yeah i'll do a bit of asking around but drop a last few bits of info that i thought of during work

So, when idling, it sounds like its skipping but as soon as it hits 3k+ RPM its got a nice solid note to it and doesnt sound like its missing, it hesitates a little driving but that could be too lean a mix on the carbs.

it's a 2" straight through for an exhaust (haven't cut a muffler/resonator int yet) so if that could be causing issues let me know 

Also when idling, it seems to have that fuely smoke and kind of oily moisture by the looks/smell etc of it. when it backfired the other day on 1342 it basically shotgunned the black moisture into my roller chest (looks like automotive homicide now)  

Ive also read people having to recurve the electronic dizzys, so could that also be an issue in regards to rough low rpm but smoother up past 3k rpm? 

Cheers in advance again for putting up with my spam haha

Link to comment
Share on other sites

The exhaust won't help, I reckon free-flow pipes make it difficult for a motor to idle smoothly. Mind you, that usually goes with the cam grind people use with big exhausts.

Carb sounds like its rich at idle, but 2minutes on a mixture meter will tell you. Ask your local tune-up garage how much to check mixture & timing.

Check out the work I did on The Girls KE70 electronic dizzy to get it to work, it was very flat and slow before I did it. You can muck around and do it for free, or pay those guys in Melb $120 odd to do it properly.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...