bug missfire

booge Learner Dubber

11 posts · joined Jan 2012 · 29 Jul 2012, 10:19 am

#915010

Hi everyone I have a 67 bug almost finished resto had it booked in for blue slip yesterday only the motor wont run properly I have changed plugs and leads rebuilt carby ajusted timing and points new condensor but sill no joy she idles a bit rough bit under load verry unhappy miss fires no power any ideas?

TorxKiwi Officially Full-On Dubber

231 posts · joined Jun 2011 · 29 Jul 2012, 5:41 pm

#915046

Are you sure you have the firing order correct?

http://www.vw-resource.com/misfiring.html

"Ownership of a Beetle is not a destination it is a journey."

Bob down Wolfsburg Wizard

455 posts · joined Jan 2012 · 29 Jul 2012, 6:06 pm

#915053

also maybe useful to work out which cylinder shes not firing on?

greedy53 Bishop of Volkswagenism

3,062 posts · joined Mar 2006 · 29 Jul 2012, 6:44 pm

#915071

are you using a new dissy cap and condenser and leads i chased a misfire for blody weeks turned out to be a dicke lead
good luck

👍👍😂🙅🥷😬🤓

booge Learner Dubber

11 posts · joined Jan 2012 · 29 Jul 2012, 6:57 pm

#915083

Firing order looks ok have pulled a lead off each plug and runs worse each time so all leads work and plugs ok should I look at valve clearances or bite the bullet and take it to a mechanic

Sides Veteran Volks Folk

2,220 posts · joined May 2007 · 29 Jul 2012, 7:33 pm

#915096

Hmm... could also be a result of "rebuilt carby"... when you put it back together did you set the mixture screw set correctly ???

Also are you sure the coil is good ???

IMHO tappet adjustment would have to be SEVERELY out to cause it to break down under load like you're talking about....

VWDCQ vice pres & web dude - vwdcqinc.org.au
Join a car club - get car peeps

My toys
'70 Hillclimb Bug 'Jezebel' w/- Haltech EFI - http://bit.ly/VwTNtQ
'60 KG Coupe - resto kinda started
01 New Beetle - gf's car, but I turn the spanners

66deluxe Custom Title Time!

1,593 posts · joined Aug 2005 · 29 Jul 2012, 7:35 pm

#915099

The worst misfire i ever had was due to a dud rotor button.

This is my Volkswagen, there are many like it, but this one is mine. Without me my Volkswagen is useless, without my Volkswagen, I am useless.

61 Karmann Ghia 2110cc type1 w Los Panchito's
66 Deluxe Beetle 2270 type 4
10 Subaru WRX Impreza

booge Learner Dubber

11 posts · joined Jan 2012 · 29 Jul 2012, 7:52 pm

#915103

Coil was my next move I also noticed when I pulled the tube off the Carby for the vac advance there was no real difference I have seen video of the motor changing quite a bit could there be a problem there ?

bajachris88 The international telephone dialing code for Antarctica is 6

6,661 posts · joined Apr 2005 · 29 Jul 2012, 8:06 pm

#915110

have a read of this Misfire article from vw-resource.com. It may be of assistance.

http://www.vw-resource.com/wires_plugs.html#misfire

(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 👍
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta!

booge Learner Dubber

11 posts · joined Jan 2012 · 29 Jul 2012, 8:29 pm

#915119

thanks i will look to see if i have the right plugs tomorrow its so frustrating to be so close after a 3 year build to be stumped by this

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 29 Jul 2012, 8:45 pm

#915123

booge wrote:Hi everyone I have a 67 bug almost finished resto had it booked in for blue slip yesterday only the motor wont run properly I have changed plugs and leads rebuilt carby ajusted timing and points new condensor but sill no joy she idles a bit rough bit under load verry unhappy miss fires no power any ideas?

When You say no power...
Can it be driven? I could never drive Mine when restoring it, but it started and idled perfectly... the accelerator pump on the carby was block by old fuel... [it still is, in the shed]
but Mine idled perfectly..
what about the distributor cap? wipe inside with petrol or metho or WD40 etc..
also check the rotor inside the dizzy cap..
they have a resistor in them to stop radio interference and they can burn out... not common but does happen..
also wipe it all over with petrol etc too..
make sure the coil is connected + to POWER
- to distributor as an engine may go even connected wrong way around...
All spark plug coil leads should be checked with an ohm meter
unless they are the original wire type..
as silicone etc can open circuit easily...
My new lead to the coil broke inside the lead first time I pulled it off the coil... sounds like a coil or dizzy problem..
is the engine earthed??? there should be a lead on the gearbox, other wise the power has to find its own way thru the gearbox etc.. engine & gearbox are on rubber mounts..

Better to try everything Yourself... unless You have a good VW air cooled mechanic nearby...
stay away from any other mechanics unless they are old and retired.. lol

cheers

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 29 Jul 2012, 8:51 pm

#915126

booge wrote:Coil was my next move I also noticed when I pulled the tube off the Carby for the vac advance there was no real difference I have seen video of the motor changing quite a bit could there be a problem there ?

mine doesn't do anything with any vacuum hoses off..
apart from stop the carby from advancing...
what engine and carby and dizzy are we talking about..

You have fuel [not old fuel] air, and need a good spark..
compression should be good...
tappets been double checked?
points correct? 1432 timing cylinders.
timing light at revs?
Dizzy 009?? or vacuum & mechanical [SVDA]
if its real bad idle, You haven't replaced the dizzy cap with one from another dizzy as the caps can be different and the rotor is the correct one for that distributor..?

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

booge Learner Dubber

11 posts · joined Jan 2012 · 29 Jul 2012, 9:04 pm

#915131

I know of a mechanic in Sydney not far from me you might have heard of him Andrew in north rocks Rd push come to shove will tow to him
thanks to all for your help will let you know how we get on

ian.mezz I never said, I could write or spell

3,913 posts · joined Sep 2004 · 30 Jul 2012, 7:04 pm

#915273

did you put a fresh tank of petrol in him.
It may help to hold the revs up a bit to get any old petrol out of the system.

😂🤪😂🤪😂
car forums. where a lot of peoples good intentions end up taking a good old car off the road forever never ever to see the road again. 🥲

booge Learner Dubber

11 posts · joined Jan 2012 · 31 Jul 2012, 4:52 pm

#915419

she is booked in for Thursday week at Andrew Dodds for repair I am dying to know what he finds once again many thanks to all for your advice I will let you know the result

psimitar Son of Jim - Creator of Good

2,506 posts · joined Jan 2009 · 2 Aug 2012, 10:27 pm

#915768

Sounds like an air leak. best thing to do is use some 180 grit wet n dry on a flat pane of glass and some wd40 to sand the manifold flanges flat and also the underside of the carb.

Go to a motor factors and buy a roll of oil resistant gasket material. Should be 1-1.5mm thick stuff. Cut all gaskets from this and this will ensure that everything seals well on re-assembly. The metal inlet gaskets only work well once and only with perfectly flat mating surfaces.

madness is in the eye of the beholder 👍