[Aircobra101]

1. have spark at the plugs
2. checked distributor rotor alignment with notch on housing and #1 cyl at tdc. ( arms not on lobes) and 10deg mark at the flywheel
3. fuel in the carb float chamber
4. points gap is 0.4
.. all i get is a massive backfire every couple revolution
only thing i can think of is that i stuffed up the belt timing !
any ideas?

[Gwagensteve]

Yep. Timing is out.
Are you sure the engine is timed with #1 at TDC? suzuki have a habit of timing with #3 at TDC.

[sideways]

Sounds like the dizzy is 180 degrees out. Pull it out and put it back in with the rotor facing the opposite side, or just swap all the plug leads forwards 2 places on the cap.

[303zuke]

Aircobra101 wrote:

1. have spark at the plugs
2. checked distributor rotor alignment with notch on housing and #1 cyl at tdc. ( arms not on lobes) and 10deg mark at the flywheel
3. fuel in the carb float chamber
4. points gap is 0.4
.. all i get is a massive backfire every couple revolution
only thing i can think of is that i stuffed up the belt timing !
any ideas?

Yep, either the timing is 180Deg out, or your ignition leads are set 1-3-4-2 either clockwise or anti-clockwise (or vice-versa). Swap the Ignition leads over for cyls 2 and 3 for a quick check.

[Aircobra101]

thanks everyone
1. the manual is clear on the dizzy timing #1 cylinder with valves firmly closed
2.its actually really hard to tell from the FSM photocopy. this what i was able to work out from the picture
look st the front of the dizzy and #1 cyl at front of car
12 o'clock #3
3 o'clock #1
6 o'clock #2
9 o'clock #4
is that right?
and i move to
12 o'clock # 2
3 o'clock # 4
6 o'clock # 3
9 o'clock # 1
that will move the timing

[Aircobra101]

the notch is at 3o'clock mark, so i must be firing 1-2-4-3
been looking on the net and found this
https://www.suzimotive.com.au/technical.htm
1-3-4-2 which means the rotor moves anticlockwise? i cranked and the it definitely clockwise
i'm confused . if i wire it 1-3-4-2 CLOCKWISE, it doesn't match the FSM

[bumstein]

Nah it moves clockwise. Firing order is 1, 3, 4, 2.

Think of it this way, it’s a 4 stroke motor so in one cycle the 1st piston goes up and down twice.

The cycle goes like this.

1. Intake. Fuel mixture dragged into the cylinder by vacuum when the piston goes down.
2. Compression. piston goes up compressing the mixture.
3. Ignition, combustion in the cylinder drives piston down.
4. Exhaust. Burnt mixture expelled by piston going up.

Then the cycle repeats. Each piston is at top dead centre twice in this cycle.

If the dizzy is 180 degrees (it’s really more like 360 degrees out) out then it’s trying to ignite the mixture between steps 4 and 1. So the first piston is at top dead centre but it’s got little fuel in there as it’s just been trying to expel exhaust.

Find top dead centre just after the compression stroke. After the intake valve closes then comes the upward compression stroke. When the piston reaches the top set the dizzy up to ignite cylinder 1 just before then.

[Aircobra101]

so my wires are wrong? 1, 3, 4, 2. with #1 at the notch?

[bumstein]

I haven’t got a dizzy in front of me but the leads are usually marked with the cylinder number. If you’re looking straight at the top of the dizzy cap #1 lead is at the top (12 o’clock). The cylinder 3 lead is to the right (3 o’clock), cylinder 4 lead at the bottom (6 o’clock) and then cylinder 2 lead at 9 o’clock.

Have you ensured that the dizzy rotor is at the 1st cylinder lead when the 1st cylinder is at top dead centre after the compression stroke?

[Aircobra101]

leads are aftermarket with no marks.
manual says to line up rotor with notch on distributor, which is at 3 o'clock. so that goes to #1 cylinder?
sierra f10s have dizzy on the other side?

[Aircobra101]

Attachment:

dizzy.jpg

[303zuke]

303zuke wrote:

Swap the Ignition leads over for cyls 2 and 3 for a quick check.

You have spent more time typing and posting pics rather than doing this.

Step 1: Go to car and open bonnet.
Step 2: Swap leads on the dizzy cap for 2 and 3 cyls.
Step 3: Start engine. Does it run? Yes = , no = Step 4
Step 4: Swap leads for 1 and 4 cyl. Start engine. All good? yes = , no = step 5
Step 5: Swap leads back for 2 and 3 cyl.

Should take no more than 2 minutes. Job done, move on.

[Darrell]

Found a pic and marked it, hope it's correct for yours

[Ratman407]

so I had the same issue today turns out I put the dizzy 180 wrong and confired by the fact swaping 1to4 and 2to3 and she started

my question to the brain trusts is it save to leave with the leads swapped or should I pull the motor out and flip it ASAP?
its a g16b 1995 model if that makes any differnce

[303zuke]

Ratman407 wrote:

so I had the same issue today turns out I put the dizzy 180 wrong and confired by the fact swaping 1to4 and 2to3 and she started

my question to the brain trusts is it save to leave with the leads swapped or should I pull the motor out and flip it ASAP?
its a g16b 1995 model if that makes any differnce

Perfectly safe. You can set the dizzy up so that No1 cyl is in any position at all; 12 o'clock, 3 o'clock, 6 o'clock, 9 o'clock. It makes no difference at all as long as the crank, cam and ignition are all set to fire at the same time.

Leave it as you have it now, but finish the job with a timing light.

[Aircobra101]

well, thank you very everybody who replied to this thread
the order is definitely 1,3,4,2 as you can see from the photo and i'm exactly 180 degrees out because my #1 is diagonally opposite the dizzy notch
stay tuned for the next instalment

Attachment:

dizy.jpg

[303zuke]

Aircobra101 wrote:

stay tuned for the next instalment

How does it take you over a week to swap around some leads?

303zuke wrote:

You have spent more time typing and posting pics rather than doing this.

Should take no more than 2 minutes. Job done, move on.