| [ Total Views: 821 | Total Replies: 18 | Thread Id: 62000 ] |
|
|
 geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on April 23rd, 2007 at 11:25 AM |
|
|
34PICT Idling erratic
Bog std 1600tp.
Idle set up ok as per manual
Once up to temp, the idle speed doubles or triples intermittently. I can sometimes bring it back down by engaging gear & letting the clutch out ie
almost stalling temporarily then it reverts to normal speed.
As these carbs perversely vary the idle speed by the amt of air they suck cf the amt of petrol that goes in then it seems that too much air gets in
intermittently???
No it's not a throttle stop prob- it stops where it should & the throttle spindle seems OK- anyway that would lean out the mix & cause stalling.
Anyone been down this road B4?
|
|
|
koolkarmakombi
Veteran Volks Folk
enkarmarising
Posts: 2078
Threads: 158
Registered: June 16th, 2003
Member Is Offline
Location: viva brisvegas
Theme: UltimaBB Pro Blue ( Default )
Mood: do you see the bats?
|
| posted on April 23rd, 2007 at 11:43 AM |
|
|
could be the timing is wrong, advance weights sticking, vacuum leak.
Original dizzy or 009?
This disclaimer does not reflect the thoughts or opinions of either myself, my company, my friends, or my dog: don't quote me on that; don't
quote me on anything; this disclaimer is subject to change without notice; text is slightly enlarged to show detail; resemblance to actual persons,
living or dead, is unintentional and coincidental; dry clean only; do not bend, fold, or mutilate; anchovies or jalapenos added to this disclaimer
upon request; your mileage may vary; no substitutions are allowed; for a limited time only while supplies last; offer void where prohibited; this
disclaimer is provided "as is" without any warranties expressed or implied
|
|
|
 Bizarre
Super Moderator
The artist formerly known as blue74l
Posts: 12755
Threads: 731
Registered: August 25th, 2002
Member Is Offline
Location: Abbotsford, Sydney
Theme: UltimaBB Pro Blue ( Default )
|
| posted on April 23rd, 2007 at 12:57 PM |
|
|
The fact that it plays up once the choke comes off suggests air leak
Once it is up to temp and idling is flucuating Get a can of WD 40 and soak the inlet manifolds. It the revs come back down - there is your leak
Also inspect the manifold boots. Bit hard to pray and soak these - but give it a go
Futue te ipsum!!!
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on April 23rd, 2007 at 01:41 PM |
|
|
KKK I thought about that!
Stock dizzy.
Gawd these things r getting near 40yo! The idle speed does change as you change the timing so I wonder if the timing is changing intermittently? At
idle, it's all vacuum so if it leaked then the timing would retard which would slow it down. But if the centrifugal plate with the weights was
wobbling around & rotating backwards & forwards(at idle no tension) that could cause a momentary advance which would increase the idle speed. Then
when I nearly "stall" it may re-set back to where it should be!
Geez! I haven't had a dizzy apart in years but I'd better have a look!
Thnx for the insight.
I'll look for suck leaks, but they would lean out the mix & cause stalling. But it's easy enought to eliminate with WD40!
|
|
|
koolkarmakombi
Veteran Volks Folk
enkarmarising
Posts: 2078
Threads: 158
Registered: June 16th, 2003
Member Is Offline
Location: viva brisvegas
Theme: UltimaBB Pro Blue ( Default )
Mood: do you see the bats?
|
| posted on April 23rd, 2007 at 02:37 PM |
|
|
Don't pull it apart, just spay good penetrating fluid down it, the top plates are often dry and resist turning and returning. Check the vacuum can
is working and the hose ok. They run off ported vacuum so the vacuum levels rise as the throttle plate opens to give more advance on part throttle.
If it advances then doesnt return properly it will run higher on idle. The air leak will increase revs if your idle mix is rich. Hence the running
well on choke.
If you are using a 34 pict type carby you should be using a svda dizzy. Weight driven advance and a vacuum can.
Was it running well then started lifting revs? When did it start?
This disclaimer does not reflect the thoughts or opinions of either myself, my company, my friends, or my dog: don't quote me on that; don't
quote me on anything; this disclaimer is subject to change without notice; text is slightly enlarged to show detail; resemblance to actual persons,
living or dead, is unintentional and coincidental; dry clean only; do not bend, fold, or mutilate; anchovies or jalapenos added to this disclaimer
upon request; your mileage may vary; no substitutions are allowed; for a limited time only while supplies last; offer void where prohibited; this
disclaimer is provided "as is" without any warranties expressed or implied
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on April 23rd, 2007 at 02:59 PM |
|
|
Yes idles perfectly at traffic lights & it just suddenly increases without any prompting or blipping. Then I put in top gear, let the clutch out & the
idle revs drop to normal & stay down, usually. Started happening after last point change.
My SC has a 1600SP with a 009. I am going to swap distribs over to see if the idle improves. Don't like 009's due the dreaded flat spotting on TP's
but the SC runs real well using a 28PCI with about a 130 main jet & slightly bored out venturi. The MPG is dismal, however.
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on May 27th, 2007 at 07:52 PM |
|
|
Finally got around to do the swap!
Results are a great & stable idle but, you guessed it, an annoying flat spot.
Has anyone tried this??
http://www.aircooledtech.com/34pict3_modification/
Or is it viable to repair/replace the stock dizzy?
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on May 30th, 2007 at 10:26 AM |
|
|
OK, I've just done the mod as described in the link on the prev post.
1st impressions r good. Full bore = no flat spots but part throttle gave a bit of hesitancy. I then slightly enriched the idle mix & advanced the ign
timing to just before the ping-point.
EUREKA!! Excellent acceleration full or part throttle!
THIS IS A GOOD MOD.
Some notes on the job:
The screws that hold the throttle disc in are peened over (so that they don't fall in!) so the threads may get chewed out when u extract them. U may
need a tap & die to clean up- 4mmx0.75.
I was concerned that as I decommissioned my oxy, I may not have enough heat to solder. The kitchen blow torch I use for creme brulee's worked fine. U
need flux (Baker's Soldering Liquid) or resin cored solder. I used both. Make sure u countersink the hole first & have the disc on a flat surface or
the solder will run & stick underneath giving you a bigger filing job.
When re-assembling, use loc-tite on the threads & re-peen the ends of the screws. I used a blunt screwdriver & some blunt force trauma- ie a hammer.
Blow it out well with comp air- there WILL be filings.
|
|
|
1303Steve
A.k.a.: Steve Carter
Scirocco Rare
Posts: 8636
Threads: 559
Registered: August 27th, 2002
Member Is Offline
Location: Sydney, NSW
Theme: UltimaBB Pro Blue ( Default )
Mood: Parrot Heading
|
| posted on May 30th, 2007 at 02:05 PM |
|
|
Hi
You need to set your total timing with the 009 to 32 degrees total maximum on a stock motor, your motor is probably pinking now, but you cant hear it,
but a long hill on a warm day might show it up. Excess timing is like heroin, feels good until your bodies F%&#@, the air-cooled motor makes more
power with timing notched up, but for how long until the heads lift off or you bearings are screwed.
So how does the air bypass work now that the hole is soldered up?
Steve
|
|
|
VWCOOL
23 Windows of Awesome
Posts: 5158
Threads: 235
Registered: June 19th, 2003
Member Is Offline
Location: In the shed... Lake Macquarie NSW
Theme: UltimaBB Pro Blue ( Default )
Mood: happy to help
|
| posted on May 30th, 2007 at 02:19 PM |
|
|
| Quote: | Originally
posted by 1303Steve
Hi
You need to set your total timing with the 009 to 32 degrees total maximum on a stock motor, your motor is probably pinking now, but you cant hear it,
but a long hill on a warm day might show it up. Excess timing is like heroin, feels good until your bodies F%&#@, the air-cooled motor makes more
power with timing notched up, but for how long until the heads lift off or you bearings are screwed.
So how does the air bypass work now that the hole is soldered up?
Steve
|
...yep, or you crack the case
Pay your debts, CxxT
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on May 30th, 2007 at 04:48 PM |
|
|
Good point! In the absence of a dial, wot's the distance along the rim of the pulley from the notch for 32 degrees?
I'm not talking bucketloads of advance. I twisted the dist abt 2mm off the static setting!
Doesn't the premixed idle mixture exit UNDER the throttle disc?? It must or it wouldn't be idling at all! I don't have a manual here to check.
I'm guessing the idle mix is quite a bit richer but it wasn't sooting & I'll keep an eye on the plugs over the next week or so. That should also
show up any pre-ignition too I guess.
I'm tolld 009's are made in China now. I'm buying another for the SC but 2nd hand due to quality worries (?).
|
|
|
1303Steve
A.k.a.: Steve Carter
Scirocco Rare
Posts: 8636
Threads: 559
Registered: August 27th, 2002
Member Is Offline
Location: Sydney, NSW
Theme: UltimaBB Pro Blue ( Default )
Mood: Parrot Heading
|
| posted on May 30th, 2007 at 05:23 PM |
|
|
Hi
I read that other page and he was talking about timing at 5 AFTC, our local cars with a single vacuum dizzy were set at 7.5 BTDC, our 71 Supers had
dual vacuum advance unit and were set at 5 ATDC.
As far as the distance goes you can measure the circumference of your pulley then divide it by 360 the x by 32 to give you right total figure using a
timing light.
The idle air on 34 Pict 3 goes via the idle cutoff valve and idle screw, I guess that if your car is idleing now OK you must have had to wind air
speed screw out a bit to compensate for the hole being closed of, interestingly the early dual vacumm cars had a much larger hole in the butterfly,
they were pigs and many were converted to single vacum, Ive seen lots that were converted but left at 5 ATDC.
Steve
|
|
|
 vw54
Super Administrator
Always Waiting 4 Friday
Posts: 16723
Threads: 378
Registered: August 26th, 2002
Member Is Offline
Location: Sunny Sydney
Theme: UltimaBB Pro Blue ( Default )
Mood: Oval resto ongoing
|
| posted on May 30th, 2007 at 05:52 PM |
|
|
Have you replaced the 2 small O rings in the idle and fule mixture screws on the side of the carby I thing there may be air suckin through there
as well also check the rubber mainifold boots for leaks as they expand when hot
|
|
|
beerdoc
A.k.a.: Doc
Insano Dub Head
Posts: 838
Threads: 42
Registered: July 27th, 2004
Member Is Offline
Location: Geelong Vic
Theme: UltimaBB Pro Blue ( Default )
Mood: Its all good
|
| posted on May 30th, 2007 at 07:43 PM |
|
|
| Quote: | Originally
posted by vw54
Have you replaced the 2 small O rings in the idle and fule mixture screws on the side of the carby I thing there may be air suckin through there
as well also check the rubber mainifold boots for leaks as they expand when hot
|
What Dave said I have had same problem
Cheers Doc
reVOLKS at Fyansford Geelong
20th OCT 2007 STAY TUNED FOR DETAILS
 |
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on June 3rd, 2007 at 06:14 PM |
|
|
Pulley is 170mm diam. Circumference is DxPi ie 170x3.14 which is 534mm.
Then 360deg is 534mm so 32deg is 47.5mm. So to time the 009 put a blob of liquid paper 47.5mm away from TDC & hook up the strobe & line up the blob
with the crankcase seam at full bore by twisting the dist. Well, t'would appear I needed a bit more advance! It's running real good now!
BTW, just a thought on audible pings. I've owned a heap of old Jags (but I don't miss'em) & the XK eng had a Lucas dist with a screw vernier to
make small timing adjustments "on the road". The factory advice was to chose a long slow incline & plant the foot at 30MPH in top gear. If it
didn't ping, advance 1-2 clicks on the vernier until it started to ping, then 1-2clicks retard.
Not applicable to VW?
|
|
|
1303Steve
A.k.a.: Steve Carter
Scirocco Rare
Posts: 8636
Threads: 559
Registered: August 27th, 2002
Member Is Offline
Location: Sydney, NSW
Theme: UltimaBB Pro Blue ( Default )
Mood: Parrot Heading
|
| posted on June 4th, 2007 at 12:07 AM |
|
|
Hi
Good figuring.
The back it off after the ping is OK on watercooled car, air coolers are littel more sensitive and with the mechanical noise that they make it can
hard to pick.
I saw an intersting feature on an old Jag once, the oil light was hooked up to the - side of the coil, no oil pressure, no ignition.
Arrr, Lucas the prince of darkness, now owned by Bosch, scary thought.
Humour, do you know why poms drink warm beer? Lucas make fridges.
Steve
|
|
|
geodon
Wolfsburg Wizard
Posts: 478
Threads: 63
Registered: August 28th, 2002
Member Is Offline
Location: geelong
Theme: UltimaBB Pro Blue ( Default )
Mood: stumbling
|
| posted on June 4th, 2007 at 08:53 AM |
|
|
Steve, guess wot's makin da sparks on my MGA 1500???
A Bosch Dist.!!! TA DA!
[ Edited on 3-6-2007 by geodon ]
|
|
|
beerdoc
A.k.a.: Doc
Insano Dub Head
Posts: 838
Threads: 42
Registered: July 27th, 2004
Member Is Offline
Location: Geelong Vic
Theme: UltimaBB Pro Blue ( Default )
Mood: Its all good
|
| posted on June 4th, 2007 at 09:31 AM |
|
|
Go and see Hank in vines road and tell him Doc sent ya:thumb if something like this happens again
[ Edited on 3-6-2007 by beerdoc ]
Cheers Doc
reVOLKS at Fyansford Geelong
20th OCT 2007 STAY TUNED FOR DETAILS
|
|
|
1303Steve
A.k.a.: Steve Carter
Scirocco Rare
Posts: 8636
Threads: 559
Registered: August 27th, 2002
Member Is Offline
Location: Sydney, NSW
Theme: UltimaBB Pro Blue ( Default )
Mood: Parrot Heading
|
| posted on June 4th, 2007 at 11:34 PM |
|
|
| Quote: | Originally
posted by geodon
Steve, guess wot's makin da sparks on my MGA 1500???
A Bosch Dist.!!! TA DA!
[ Edited on 3-6-2007 by geodon ]
|
Hi
You must be a strange person, German & pommie cars.:o
Steve
|
|
|
