checked the timing marks, its all fine

managed to get my accuspark fitted dizzy to work, the rotor arm didnt wanna work with the dizzy cap i was using as its a different style, put the old rotor arm on and it fired straight up! ffs lol

anyway now that its installed, the idle is MUCH better!! i set the timing to 6 degrees BTDC with the vac advance blocked off, is that the correct way?

tok it for a quick rag, it was pulling really well at first (guessing the points were fucked) and it was much quicker!

it still backfires through the carb though? i thought that was a timing related isue, but I've just timed it up!

did i do it correctly or are you meant to have vac advance connected?

checked my autodata manual, said to set the timing with the vac advance disconnected, nothing about blocking it off. so i did that, I've also cleaned up the rotor arm and the pins in the dizzy cap and made sure everything was on tight.

so surely it cant be down to ignition now. it must be something else.

its like a kinda cough from the carb, does it randomly, at any rpm. dunno what would cause it

I've read this article just now which seems pretty good

http://www.ehow.com/info_12206850_car-back...carburetor.html

it mentions about a lean misfire through the carb, it sounds like it may be what I'm getting, also it says about the accelerator pump failing causing a flat spot when you hit the throttle, mine does this too!

so could it possibly be a case of a weak mixture and a dodgy accelerator pump?

heres my engine by the way if its any help.

Edited 15 May, 201214 yr by erixtar1992

accelerator pump is working fine, and I've richened up the mixture. still fucking backfiring through the carb throat :@

does idle smoother with a richer mixture though!

5 deg + or -1 deg BTDC at 750 to 850 rpm.

Hoses disconnected and plugged (eg golf tees)

Have you got the vacuum advance line from dizzy going to the port above the throttle plate?

See Haynes Polo 82-90 page 200

http://www.recarbco.com/technical/newtrouble.html#Cold_drive

No Hall sender to go wrong. Part throttle enrichment diaphragm might have a split.

Edited 15 May, 201214 yr by dvderlm

Sorry yeah meant 5 degrees

I've currenly got the bottom half of the carb off in my room, and i have the bottom half of the carb from my other engine (autochoke was the problem on that one)

So I'm gonna put the two together in a minute and see if it is the carb afterall

yeah, changing the carb over did nothing.

WTF IS WRONG WITH THIS FUCKING THING AHHHHH

could it be something worse, as in a fucked valve or something? so tempted to swap the engines over grrr

G40 or GTFO!!!!! :lol:

Is there a chance that there is a hot spot in a certain cylinder thats causing the misfire?

Dodgy plug? Carbon build up? tappet adjustment?

its got brand new plugs!

tappets do need adjusting yes, sounds like an old fiesta at the minute! not sure if that would cause the problem though :s whacha reckon?

Just chuck some bike carbs on

Just chuck some bike carbs on

but not declaredddd wanna keep it single carb for now really!

Buy a Good one then!!!

Buy a Good one then!!!

i dont think the carb is the problem tbh! its gotta be something random, its timed up properly, and the carb all seemed fine! gotta be something to do with the lump itself no?

consulting the book of lies:

Engine Misfire:

Spark Plug gap or contact points dwell angle incorrect

Faulty Coil or Condenser

Dirt or Walter in the carb

Burnt out valve

Leaking HG

Cracked Dizzy Cap

Incorrect valve clearances

Uneven cylinder compressions

Engine Backfire:

Carb out of whack

Timing out of whack

Valve clearances out of whack

sticky valves

I'm inclined to follow the ones in bold.

Valve Clearance: How to according to the book of lies

1. Turn engine so both cam peaks for cylinder 1 are pointing upwards, at equal (but opposite) angles to the stems.

2. Insert feeler blade (inlet is 0.10mm, exhaust 0.20mm)between cam and follower, if blade is not a firm sliding fit turn adjustable ball stud using an allen key

3. Repeat the procedure (in 1&2) for the remaining valves, in following order 3,4,2 (firing order)

knew you were going to ask, so i beat you to it.

thnk ill try and find someone who knows what there doing first

ill get on the caseee, cheers for that!

knew you were going to ask, so i beat you to it.

hahaha

looks pretty easy to be honest.

but how many people have feeler gauges as normal tools.

My spark plug gap tool lives in the ashtray in the car. when i needed one originally people looked at me strange or said there "Pre" gapped....

yeah exactly haha, ill try n get something done tomorrowww

The clearances are fairly easy to check mate.

Basically you need it off cam so valves are fully shut and measure the gap between follower and cam lobe with feelers.

Valve Clearance: How to according to the book of lies

1. Turn engine so both cam peaks for cylinder 1 are pointing upwards, at equal (but opposite) angles to the stems.

2. Insert feeler blade (inlet is 0.10mm, exhaust 0.20mm)between cam and follower, if blade is not a firm sliding fit turn adjustable ball stud using an allen key

3. Repeat the procedure (in 1&2) for the remaining valves, in following order 3,4,2 (firing order)

I always used the rule of 9 ie #1 fully open adjust #8 , #2 open adj #7 and so on

got some feeler gauges from a guy at work, so i guess i have to wait for my engine to cool down now?

got some feeler gauges from a guy at work, so i guess i have to wait for my engine to cool down now?

Autodata says to adjust with the engine HOT

got some feeler gauges from a guy at work, so i guess i have to wait for my engine to cool down now?

Autodata says to adjust with the engine HOT

oh shit really?? i better get started then!

any tips nige? its just an allen key right?

do i just slide the appropriate feeler guage under the camshaft (when its on the back of the lobe) and turn the allen key till i just starts to grip?

There's hot and cold settings. The ones I gave were for setting when cold