Benzine
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| posted on 27/6/05 at 02:06 PM |
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Pinto and webers make Ben something something...
Go crazy?
Don't mind if I do!
Here are my n00b problems. I've been building a 2.0 litre Mk pinto since last year (been away at uni most of that time) The build so far has
been great but now i've got to the engine, something I know little about.
The engine is in, ignition all set up, it's timed up (local garage did this last week but at the time the ignition wasn't complete for
them to test it) Now the engine turns over and starts but something's not right... It half starts most times and dies out but sometimes it
starts really well and revs super high before I cut it.
So the thing I want to know is what is causing this and how to remedy it. Could the webers have the wrong jets (although they were ordered and fit for
a 2.0 pinto), adjustment on idle needed? What effect does a performance cam have and would I need to change anything for? I'm using an electric
Facet pump which is all set up. It's 7psi, is that right or too high? Are there other options like rolling road or somewhere that can set it
up?
Thanks for any help
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Marsdalebear
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 posted on 27/6/05 at 02:40 PM |
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IMO 7psi is waaaaay too high. 2.5-3 is a good starting point.
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DarrenW
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| posted on 27/6/05 at 02:51 PM |
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Do you know what spec the webers have been delivered to you?
What type of ignition system?
What spec is the engine?
Im using facet red top (cos i had one) and have been told to fit regulator and reduce it right down.
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Benzine
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| posted on 27/6/05 at 04:19 PM |
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quote:
Originally posted by DarrenW
Do you know what spec the webers have been delivered to you?
What type of ignition system?
What spec is the engine?
I ordered the webers for my engine from carburetor.co.uk and told them over the phone what I was using and they said they'd jet set them up
accordingly. Ignition is from burton power (third down on this page)
https://www.burtonpower.com/dets_product.aspx?App=SO&PGrp=08003&PSet=1
The engine is a 205 block pinto from totalengine.co.uk that was fully reconditioned. I told them I was to be using twin 45 webers and he upgraded the
cam to something more suitable.
I didn't know 7psi was too high. I was told by burtonpower that would be suitable (then again they've told me lots of things that have
turned out to be wrong in the past)
Spanks
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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mookaloid
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| posted on 27/6/05 at 09:12 PM |
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Sounds to me like the carbs need setting up.
Either take it to a rolling road where they know what they are doing or you could try following Dave Andrews excellent carb tuning guide here
http://hometown.aol.com/dvandrews/webers.htm
Hope this Helps
Cheers
Mark
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gazza285
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| posted on 27/6/05 at 09:27 PM |
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I presume you have checked for air leaks between the carbs/manifold and between the manifold/head. There's not much that causes an engine to rev
off throttle and air leaks are one of them.
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Benzine
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| posted on 27/6/05 at 09:30 PM |
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Cool thanks for the help.
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Bob C
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| posted on 27/6/05 at 11:04 PM |
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The biggest air leak of them all.... did you plug the manifold vacuum port for the donor car's brake servo???
cheers
Bob
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Avoneer
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| posted on 27/6/05 at 11:22 PM |
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Yep - 7 is far too high.
Needs to be 2.5-3 for sure.
Pat...
No trees were killed in the sending of this message.
However a large number of electrons were terribly inconvenienced.
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Benzine
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| posted on 12/7/05 at 06:44 PM |
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Update: I've now installed a fuel filter/regulator between the pump and the carbs. It's no longer over revving. In fact its not doing
much, almost seems to start then dies.
Is it a case of altering the pressure regulator and the idle screws on the carbs?
Oh and one problem I have is at my pump. There seems to be air trapped somewhere and I don't know how to get rid of it. This is probably a basic
bit of knowledge so I didn't make a new thread 
When the pump is working fine it purrs away but now it gets louder (I turn it off when this happens as I read they wear without fuel in) I've
tried disconnecting the fuel lines at either side and filling them up but it still happens. I think the problem is the fuel tank to pump connection,
the fuel wants to go back down into the tank before i can reconnect the line. What can I do to get rid of all the air? Clamp the fuel line (flexible)
with fuel in then reconnect it?
Thanks for any help
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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NS Dev
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| posted on 12/7/05 at 09:20 PM |
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re. the suction line from the tank, don't worry, that's normal, the fuel will run back down into the tank when the pump stops anyway, but
they will self prime again no problem anyway! They can draw air for a fair while with no bother.
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Benzine
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| posted on 12/7/05 at 10:40 PM |
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Hmm how long normally would it take to start pumping properly? Mine never seems to run quietly, it did once but since then I altered the fuel lines
between the tank and the pump, if there was a lot of air in there, would it never work properly unless this air was removed?
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Benzine
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| posted on 13/7/05 at 05:54 PM |
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I've been trying today to get it started again. When I had no pressure regulator the engine started (good) but revved seriously high so I had to
cut the power straight away (fuel pump pressure way too high)
Now the engine is starting for a split second then dying. I presume this is due to too little pressure. Can someone tell me something...if the fuel
pump is running loudly (which is due to air?) will it not be putting out much fuel pressure?
I feel so close to sorting this out yet the pump keeps on being loud. I've had it sometimes where it's purring like a kitten
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Dingz
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| posted on 13/7/05 at 09:52 PM |
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Might seem silly but is the tank clean? the suction pipe can get blocked easily by crud foating about and that would make the pump work hard to no
effect.
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Benzine
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| posted on 13/7/05 at 10:00 PM |
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Yeah it's all spanking and shiny 
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Benzine
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| posted on 14/7/05 at 09:29 AM |
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The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Peteff
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| posted on 14/7/05 at 09:56 AM |
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Facet fuel pumps are noisy. You could mount it lower down so it's not lifting fuel all the time and stays primed when you stop. It'll
still hammer when you start up though. Your float needles should cope with 7psi for a short time so raise your regulator pressure. How strong is your
throttle return spring and have you turned the tickover screw down as you may be running too high for the idle circuit to be operating.
[Edited on 14/7/05 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Benzine
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| posted on 14/7/05 at 10:33 AM |
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Throttle return springs are good, so I could screw the tickover screw down?
Are they the ones that say 'Idle mixture adjustment screw' on this diagram?
Shame my carbs came with no instructions really
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Peteff
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| posted on 14/7/05 at 07:11 PM |
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Your tickover should adjust on the linkage. They are more likely the ones that are marked throttle adjustment screw and will hold the linkage off the
stop, undo it to slow it down. Read the page on Dave Andrews site where the diagram came from, he explains it well.
[Edited on 14/7/05 by Peteff]
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Benzine
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| posted on 14/7/05 at 08:40 PM |
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Thanks for the help, it's starting now Shame it's a bit late or i'd have more time to tinker with it. Tomorrow it shall roar
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Benzine
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| posted on 16/7/05 at 04:10 PM |
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Update. (Thought I'd drag this out a big further ) I've stopped the high revving by adjusting the screw Peteff suggested 
Now the engine starts and actually idles for about 5 seconds  Which is awesome. The trouble is it eventually dies out. I'm not sure if this is
fuel pressure or it's not getting enough air. Some times it's running on 2 cylinders (front 2) and others times all 4, but mostly 2.
This is the screw I used to stop it revving really high
I was wondering if it's just a case of adjusting these screws:
...or any of these (which I haven't touched yet)
I read that article suggested which helped but I haven't quite grasped it.
Thanks for any help, so close now
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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Peteff
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| posted on 16/7/05 at 04:40 PM |
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The ones in the No7 pic are jets, put the cover back on them and don't touch them unless you have already loosened them in which case nip them
down first. There is a balance on the linkage in the picture next to the No6 which doesn't look right. Slacken it off so the tab on there is
about halfway between the two stops, it sounds like you're running on one carb more than the other. Get a 12" piece of hosepipe and put one
end to your ear and the other in the bellmouth and listen to the hiss then slacken the screw till they sound about same.
 
Rescued attachment balance.jpg
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Benzine
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| posted on 16/7/05 at 10:53 PM |
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Thanks Pete, adjusting that screw has helped Seems to be running on all four but still not idling properly, I'll spend tomorrow fannying
about with it
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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mookaloid
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| posted on 17/7/05 at 12:29 AM |
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After you have adjusted the balance as pete says - by listening to the sound through a tube, you need to adjust the idle mixture screws
1,2,3&4.
With the engine off screw them right in then 2 1/2 turns out then start the engine
Then to quote Dave Andrews:
When you are sure that the carbs are drawing the same volume of air, visit each idle mixture screw, turn the screw counter clockwise (richening) in
small increments (quarter of a turn), allowing a good 5 - 10 seconds for the engine to settle after each adjustment. Note whether engine speed
increases or decreases, if it increases continue turning in that direction and checking for engine speed, then the moment that engine speed starts to
fall, back off a quarter of a turn. If the engine speed goes well over 1000RPM, then trim it down using the idle speed screw, and re-adjust the idle
mixture screw. If engine speed decreases then turn the mixture screw clockwise (weakening) in small increments, again if engine speed continues to
rise, continue in that direction, then the moment it starts to fall, back off a quarter a turn. The mixture is correct when a quarter of a turn in
either direction causes the engine speed to fall. If that barrel is spitting back then the mixture is too weak, so start turning in an anti-clockwise
direction to richen. During this procedure, the idle speed may become unacceptably high, so re-adjust it and repeat the procedure for each carb
barrel.
Good Luck
Mark
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Benzine
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| posted on 17/7/05 at 09:00 AM |
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Ahh it's all becoming clear now, thanks a lot. It was starting to get to my head, I actually had a dream last night I was tuning an old radio
and to tune it the radio had 4 screws to adjust which I had to get the screwdriver out to turn 
The mental gymnastics a landlord will employ to justify immoral actions is clinically fascinating. Just because something is legal doesn't make
it moral.
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