Ausmini
It is currently Thu Jul 24, 2025 11:20 am

All times are UTC + 10 hours




Post new topic Reply to topic  [ 20 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: flatspot nightmare
PostPosted: Wed Apr 22, 2009 5:39 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
hey guys
ive got a 65 deluxe with a 998 and 1 1/2" SU

im sorry to repost but i think ive tried most of the stuff thats been posted.
Im trying to get rid of a big flatspot in my accerating, its low down in all gears , so it makes taking off a nightmare, whenever i go to take off i put my foot down and it just lurches and coughs and splutters. Pulling out the choke makes it work fine.

Is this something to do with the tuning?
we have recently put in a new 123 dissy, plugs and leads, i checked the oil in the dash pot and its up to the top of the little bobly bit on the end of the stick

Any help would be greatly greatly apprecieated

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 5:46 pm 
Offline
1098cc
1098cc
User avatar

Joined: Thu Aug 03, 2006 11:47 am
Posts: 1212
Location: In Transit, Sydney
MIne had a similar problem and I found it was sucking air because of a worn throttle shaft. Is there any movement in the throttle shaft?

_________________
Your silliness has been noted.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 5:51 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
sorry to be a complete noob. But how would i test it?

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 5:59 pm 
Offline
1098cc
1098cc
User avatar

Joined: Mon Mar 30, 2009 5:38 pm
Posts: 1650
Location: macquarie fields NSW
Dont be sorry for being a noob. I am one and proud of it. I have asked and read topics on here and had absolutly no idea what people are talking about. I say "yes, I understand", then go to work and ask for the translation. By the way, what is a lay shaft, and what is a cam with spider gears?
Love minis to death, but have no idea technicaly!
I bend, weld and paint things for a living!

_________________
Chuck Norris is the only person alive who can kick you in the back of the face!!
mooo, I'm a pig!


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:09 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
ok i just figured out what the throttle shaft was and checked it and it seems to be tight i tried wiggling it and pulling it and no movement

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:09 pm 
Offline
Tomboss Breweros
User avatar

Joined: Wed Dec 31, 2008 9:57 pm
Posts: 7514
Location: Causing mayhem in northern rAdelaide
roleyfoley wrote:
sorry to be a complete noob. But how would i test it?


Grab either end of the throttle shaft and try to wobble it about, if you can feel movement then it will be leaking air in.

If pulling the choke helps then it might simply be running lean, a dyno tune would sort that out and get you some more power at the same time :wink:

_________________
Dean Hutton's first car was a Mini.

kimini wrote:
:mrgreen: It's the boobs and testosterone that make this place fun-ner :lol: !!

Jimmyinamini wrote:
It's not nice to throw spank on the floor.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:18 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
cool thanks all, might have to go see the dyno guy my dad knows again, i think this might be a bit over my head

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:23 pm 
Offline
Resident Haemorrhoid
User avatar

Joined: Mon Jan 31, 2005 7:47 pm
Posts: 6815
Location: in da ACT
what sort of oil are you using in the Dashpot??

it might be a bit thick seeing its getting colder in Canberra :wink:


I use 3 in 1 oil in my dashpot and it works fine

has this issue started in the last couple of weeks if so that when it started to get colder and the oil in the dash pot may be a bit more Viscious :wink:

to check for a worn throttle shaft with the engine running spray some WD40 throught the little red straw onto both sides of the shaft if the revs increase its sucking the wd40 through and it is fuelling the engine :wink:

_________________
mtsmini wrote:
Master, you are wise beyond your years.....I am a mere grasshopper before you :D

Tombo wrote:
Gadgets has never been so right :D


Last edited by Gadgets mini on Wed Apr 22, 2009 6:26 pm, edited 1 time in total.

Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:24 pm 
Offline
1275cc
1275cc
User avatar

Joined: Fri Oct 29, 2004 6:14 pm
Posts: 4963
Location: A pub near Geelong
the throttle shaft is a part of the carb. take the air filter off, you should see an axle going through the body of the carb, just before the manifold. this is the throttle shaft.

to see if it has play, grab hold of it and try to wriggle it about. if it wriggles, it is loose. it is only supposed to spin, like an axle.

try and get your hands on an SU tuning book, and see if you can remedy if it is running lean (check the spark plugs, i think it is white deposits that mean it is running lean? don't quote me on that though)

how old is your fuel filter? i had similar problems, changed the fuel filter and all was well (but pulling the choke didn't fix mine...)

_________________
78 Leyland Mini - Prince


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:26 pm 
Offline
1275cc
1275cc
User avatar

Joined: Fri Oct 29, 2004 6:14 pm
Posts: 4963
Location: A pub near Geelong
roleyfoley wrote:
ok i just figured out what the throttle shaft was and checked it and it seems to be tight i tried wiggling it and pulling it and no movement


ok that is good :)

next, see if you are running lean.

also, check the timing. you may need to tune the dizzy

_________________
78 Leyland Mini - Prince


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:27 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
Gadgets mini wrote:
what sort of oil are you using in the Dashpot??

it might be a bit thick seeing its getting colder in Canberra :wink:


I use 3 in 1 oil in my dashpot and it works fine

has this issue started in the last couple of weeks if so that when it started to get colder and the oil in the dash pot may be a bit more Viscious :wink:


yer thats the other bit i forgot to mention it seems to be really bad on cold days, even when the engine says its warm but i always take the car to the tuner in the arvo and its never a problem

Thanks heaps i think you got it. this question is dumb i know but is 3 in 1 oil avliable at just any old auto store supercheap etc?

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:29 pm 
Offline
Resident Haemorrhoid
User avatar

Joined: Mon Jan 31, 2005 7:47 pm
Posts: 6815
Location: in da ACT
3 in 1 is the light weight sewing machine type oil you should be able to get it at Woollies or Coles :wink:

BTW there used to be a guru of SU's working at Dyno tune Braddon not sure if he is still there give them a ring i think his name was Phil, brad or even Steve :oops: :lol: :lol:

_________________
mtsmini wrote:
Master, you are wise beyond your years.....I am a mere grasshopper before you :D

Tombo wrote:
Gadgets has never been so right :D


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 6:37 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
oh yer dad knows the guys at powertune in philip so if all fails there ill give them ago .

and thanks again everyone, the help on here is amazing

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 7:23 pm 
Offline
1275cc
1275cc
User avatar

Joined: Sun Jul 01, 2007 11:25 pm
Posts: 5174
Location: Greensborough, Victoria
Sewing machine oil may be abit thin, I use dextron 3 auto trans fluid. Fill it up to the top of the piston tube......you will see the lip.

_________________
http://www.youtube.com/watch?v=nDMkVq1jRGU


Top
 Profile  
 
 Post subject:
PostPosted: Wed Apr 22, 2009 7:46 pm 
Offline
848cc
848cc
User avatar

Joined: Mon Mar 02, 2009 1:23 pm
Posts: 178
Location: Canberra
Dylan's Clubby wrote:
roleyfoley wrote:
ok i just figured out what the throttle shaft was and checked it and it seems to be tight i tried wiggling it and pulling it and no movement


ok that is good :)

next, see if you are running lean.

also, check the timing. you may need to tune the dizzy


i got the service manual for my bday and was reading through it and it said that if you pull the piston up about .8mm and if it looses power/stalls its lean so i started riching it up by turning it anti-clockwise, but i turned it a lot and this still happened, also the flat spot seem to have moved a bit higher up the rev range so now i can take off but if i put the throttle down semi hardish it goes flat so i kinda stopped playing with it scared i might end up with a huge flat spot and something going really wrong.

also how do i go about getting the oil currently in the dash pot out?

_________________
I'm grew up on the street, not the hood, the sesame st


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 20 posts ]  Go to page 1, 2  Next

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 94 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  

cron

© 2016 Ausmini. All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.