Wont start when cold - fine when warm

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Humphreysmum
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Wont start when cold - fine when warm

Post by Humphreysmum »

Need some help with my traveller please.
He wont start when cold without a lot of effort but is fine later in the day when still warm.
We have done the following:
Fitted new head , new air filter , new plugs , cleaned out carb , new battery, recent new fuel pump, electric start
Runs beautifully when he eventually starts, no smoke, no mis-firing.
Any ideas ?

Donna
bmcecosse
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Re: Wont start when cold - fine when warm

Post by bmcecosse »

Is the choke control wire connected up - does the mechanism work under the carb when you pull the knob ?
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Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Just been out and checked and its fine.
All a bit of a mistery as humphs always been a first time starter untill about 3 weeks ago and he runs like a sewing machine when we finally get him going.
Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Just gone and turned him over a few times checked the plugs and they were dry , no fuel getting to them.
Have cleaned out carb
Any suggestions ?
bmcecosse
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Re: Wont start when cold - fine when warm

Post by bmcecosse »

Assuming the fuel pump is working ok (tick tick noise on first switch-on) I still think it's likely the choke is not pulling the jet down far enough. Other possibility is low fuel level in the float chamber. It should be ~ 3/16" below the jet bridge when the fuel pump stops ticking. So - pull the choke ands then at the carb see if you can pull the jet down a bit more. To check fuel - remove the bell and piston and look down at the bridge - can you see the fuel ?
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Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Yes, can see the fuel
Choke appears to be working, he runs faster when I pull it out.
Many thanks
bmcecosse
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Re: Wont start when cold - fine when warm

Post by bmcecosse »

Aye - but the first part of the 'pull' does just increase the idling speed - further pulling should pull the jet down to richen the mixture.
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MarkyB
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Re: Wont start when cold - fine when warm

Post by MarkyB »

What happened, or was done, 3 weeks ago?

"Once you break something you will see how it was put together"
beero
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Re: Wont start when cold - fine when warm

Post by beero »

When you have started it and it is warm and running smoothly, have you tried pulling the choke out? Does it just increase the revs or does it run rough? If the revs increase but it is still smooth then, as Roy says, the cable may not be pulling the jet down.

Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Many thanks guys for the advice.
Will check all mentioned and get back to you.
Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Swapped starter from our other morris and he goes first time
New problem now though...runs smooth around town up to about 30/40mph but when I try to go faster he sounds like a tractor and wont pull.
Flat out will only do 45/50.
Any ideas please ?

THANKS
DONNA
bmcecosse
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Re: Wont start when cold - fine when warm

Post by bmcecosse »

Ahhhhh - you didn't explain the problem was down to slow cranking! Obvious really - we should have asked. As for performance - it needs a tune-up I guess. Does the carb piston lift/fall ok ? Is the air filter clean - try a run without it. Is the vacuum advance connected up and does it work as it should?
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Humphreysmum
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Re: Wont start when cold - fine when warm

Post by Humphreysmum »

Thanks Roy ( I hope you don't mind me adressing you as such)...what a gem you are!
have booked humphrey in for a re-tune and healthcheck.
He is my only car and we do 50 miles a day, 20 motorway miles.
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