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Infuriating problem when starting....
lordbenny - 28/2/17 at 02:32 PM

This has been going on for a while now can someone confirm my inkling.....

Car : Westfield 2.0 Zetec, 45 Dellortos

Issue : From cold it is very hard to start....turn on ignition, wait for fuel to get through, three pumps of the throttle then turn over. Sometime, I can catch it straight away, if not it will take absolutely ages and lately not start at all until as it eventually floods itself.....If i hook it up to another car then hey presto, it fires straight away. Just to let you know that the battery is NEW.

Once the car is warm it will start without a problem.

Can it only be that that started motor just hasn't got enough ooomph or could it be something else?

[Edited on 28/2/17 by lordbenny]


Nickp - 28/2/17 at 03:08 PM

Does it sound like it's turning over fast enough? Good engine earth?
Maybe your ignition system isn't getting the full 12V when you're cold cranking giving you a weak spark?
If it's flooding, then you've either got too much fuel or not enough spark.


Sam_68 - 28/2/17 at 03:11 PM

quote:
Originally posted by lordbenny
Can it only be that that started motor just hasn't got enough ooomph or could it be something else?



How fast is it turning over on the starter?

If it's a problem with the starter it should be blatantly obvious that it's not turning over fast enough. If that's the case, first thing to check is the engine earths and all connections to the starter.

If the starter is cranking fast enough, and you're getting enough fuel through to flood it, then next suspect would be the iginition.


lordbenny - 28/2/17 at 03:36 PM

The engine does turn over fast enough at first then seems to get slower almost instantly. If it doesn't fire first time it then doesn't really have enough grunt to fire it up and this is why it floods. As soon as it's connected to another car with jump leads, it's nice and fast and hey presto, it bursts into life.


pekwah1 - 28/2/17 at 03:40 PM

i'm no expert, but would this point towards the crank rating on the battery and whether it can cope with the engine?


Nickp - 28/2/17 at 03:41 PM

Does sound like a cranking issue then. Can you try a different battery first? Maybe your new one's not great.


leon51274 - 28/2/17 at 03:41 PM

I had the same problem and it was down to the battery not having enough cranking amps, fitted a battery with 600caa and no problem.


907 - 28/2/17 at 04:29 PM

I have Dellorto 45's on the Lotus, set up by Peter Baldwin. ( Mr Mini, Cambridge )

The cold starting procedure is to allow time for the float chambers to fill, pull out choke fully, turn key.
Engine will fire and run at 1k revs and after 10 seconds push choke in to half. I can then use a little throttle
to encourage a few more revs and then it will drive away. Pre pumping of the throttle isn't the best way
with horizontal air intakes like Webber's or Dellorto's or even bikes. IMHO

I also have an electronic distributor with it's matching coil, and a geared starter motor.

According to the rolling road dyno this set up produces 180 bhp.


HTH
Paul G


lordbenny - 28/2/17 at 04:54 PM

The battery is a Mondeo battery so far too big really, I assure you the battery is not the issue.

I don't have a choke, I thought the standard start up procedure with Dellortos was 3 pumps once the carbs were primed.


pekwah1 - 28/2/17 at 05:19 PM

it does sound strange, if you're confident the battery is fine and not the problem, i would be asking the question of why jump leads onto another car would then start yours no problem at all.

Obvious things to note:

- 2 batteries connected WILL have more cranking power than just one.
- by connecting to the other car, are you also resolving any bad earth issues as previously suggested?


miskit - 28/2/17 at 05:53 PM

When you connect to another car you are getting a proper earth - you probably even connect it directly to the engine?

- If so then that is your problem - a bad engine earth.

You can verify this by connecting a volt meter between the -ve on the battery and the engine case near the starter. You should read zero V, then crank the engine - you will see the voltage jump up - this is the voltage drop caused by the resistance of the bad earth connection.

Pretty certain that is your issue.


chris_smith - 28/2/17 at 06:37 PM

quote:
Originally posted by pekwah1
i'm no expert, but would this point towards the crank rating on the battery and whether it can cope with the engine?


I second this option, sounds like battery isn't up to the job


lordbenny - 28/2/17 at 06:38 PM

The battery is almost new and is twice the recommended Westfield size as it's a standard Mondeo battery with loads more cranking power the is needed.

I'm sure the battery earth is ok to the chassis as I have taken it off and cleaned it in a number of times.

Should I be earthing the engine in any other way?

[Edited on 28/2/17 by lordbenny]


garyo - 28/2/17 at 06:56 PM

Use a spare jump lead to earth the engine block to the battery and see if that makes a big difference.


lordbenny - 28/2/17 at 07:09 PM

quote:
Originally posted by garyo
Use a spare jump lead to earth the engine block to the battery and see if that makes a big difference.


Yep, good idea, the simplest ones always are. Will let you know the outcome.


Bluemoon - 28/2/17 at 11:56 PM

quote:
Originally posted by lordbenny
The battery is almost new and is twice the recommended Westfield size as it's a standard Mondeo battery with loads more cranking power the is needed.

I'm sure the battery earth is ok to the chassis as I have taken it off and cleaned it in a number of times.

Should I be earthing the engine in any other way?

[Edited on 28/2/17 by lordbenny]


still check the cca.. some large batteries are not all it seems (lead is expensive some lesser brands skimp on this and have a low cca yet high capacity..)...


907 - 1/3/17 at 07:42 AM

quote:
Originally posted by lordbenny
The battery is almost new and is twice the recommended Westfield size as it's a standard Mondeo battery with loads more cranking power the is needed.

I'm sure the battery earth is ok to the chassis as I have taken it off and cleaned it in a number of times.

Should I be earthing the engine in any other way?

[Edited on 28/2/17 by lordbenny]






From the negative battery terminal to a stud/bolt welded to the chassis, and from that same stud/bolt to one of the
bolts that fix the bell housing to the engine block.

Battery_________chassis__________engine block

Don't use jump lead wire as they are often cheap aluminium rubbish.

Buy some COPPER welding earth lead and proper crimp on connections to go with it. (eBay ?)

This will at least eliminate one possibility.



HTH
Paul G


Sam_68 - 1/3/17 at 09:21 AM

What ignition system are you running? Fixed advance can be a b*****d to crank over on highly-tuned engines, and if your timing is out it can show the same symptoms.


lordbenny - 1/3/17 at 09:25 AM

It's an MBE ECU if that's what you mean!


r1_pete - 1/3/17 at 09:28 AM

Try retarding the cranking spark timing a few degrees, if its too advanced the early spark will try and push the piston back down the pot, having a second battery gives enough power to get it over top.


minitici - 1/3/17 at 10:06 AM

quote:
Originally posted by lordbenny
It's an MBE ECU if that's what you mean!


MBE recommend that the ECU has a direct +ve connection to the ECU from the battery to avoid voltage drops.

From their manual:

"CHASSIS GROUND
The chassis ground should be connected to either the battery negative or a good chassis ground as show. PLEASE ENSURE VERY CLEAN SURFACES.

BATTERY POSITIVE
Battery +ve is recommended to be connected directly to the battery positive. It must not go to master switch otherwise voltage drop will almost certainly occur, creating starting issues. The switched ignition wire can be fed through the additional normally closed pins when master switch is on. This means the ECU will be switched off when the master switch is turned off. If the lead won’t reach, use an extension lead and join as follows."


Sam_68 - 1/3/17 at 10:36 AM

quote:
Originally posted by r1_pete
Try retarding the cranking spark timing a few degrees, if its too advanced the early spark will try and push the piston back down the pot, having a second battery gives enough power to get it over top.


^^^ This.

Or invest in a geared, high-torque starter motor: they work wonders on high compression Crossflows!


907 - 1/3/17 at 11:13 AM

quote:
Originally posted by Sam_68
quote:
Originally posted by r1_pete
Try retarding the cranking spark timing a few degrees, if its too advanced the early spark will try and push the piston back down the pot, having a second battery gives enough power to get it over top.


^^^ This.

Or invest in a geared, high-torque starter motor: they work wonders on high compression Crossflows!




I bought a Wosp. It's worth having just for the sticker.

Description
Description


stevebubs - 1/3/17 at 11:47 AM

Symptoms, to me, point to either battery cranking amps too low, or cranking timing needs adjusting..


lordbenny - 1/3/17 at 12:10 PM

quote:
Originally posted by minitici
quote:
Originally posted by lordbenny
It's an MBE ECU if that's what you mean!


MBE recommend that the ECU has a direct +ve connection to the ECU from the battery to avoid voltage drops.

From their manual:

"CHASSIS GROUND
The chassis ground should be connected to either the battery negative or a good chassis ground as show. PLEASE ENSURE VERY CLEAN SURFACES.

BATTERY POSITIVE
Battery +ve is recommended to be connected directly to the battery positive. It must not go to master switch otherwise voltage drop will almost certainly occur, creating starting issues. The switched ignition wire can be fed through the additional normally closed pins when master switch is on. This means the ECU will be switched off when the master switch is turned off. If the lead won’t reach, use an extension lead and join as follows."


Just removed and tidied up all the earths which include the ECU earth AND the engine/chassis earth......there was some corrosion on the earth post......seems like this could well be my cure as it started straight away, the starter whizzed a LOT quicker than normal (Fingers crossed) Will get back to you when I've left the car for a day or two then tried starting it from cold.


[Edited on 1/3/17 by lordbenny]


02GF74 - 2/3/17 at 08:19 PM

for best starting, you should have cable from battery - to chassis and then another cable from that point to the starter motor.

from the symptoms above, it does sound like there was a bad contact - the metal contacts have to be in top condition as the starter can draw in excess of 100 A and any high resistance, even fraction of an ohm, will drop voltage and hence power to the starter.

also clean the positive cables to ensure there is good contact.


lordbenny - 2/3/17 at 09:03 PM

Thanks for your help everyone

[Edited on 2/3/17 by lordbenny]