Help with starting issue

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markh
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Help with starting issue

Post by markh »

I've reached the end of my (limited!) knowledge on this one...

Car is a 1970 911T

About two months ago the fuel pump - a Facet in the engine bay - started just constantly loud ticking at startup. Normally it ticks loudly for a few seconds and then when up to pressure goes to a quiet whirr.

I replaced the fuel pump with the same again along with new hoses, clips etc. I disconnected the batteries etc in the process. Once the new pump was all fitted I refitted the batteries but they were weak so I put them on charge for the night.

The next day all was well - pump primed, car started as usual - happy days!

Now back from a few weeks away and went to start the car on Saturday and as usual pump primed when ignition turned on but then on full turn of the key nothing. I assumed battery low again but checked batteries and all ok.

Checked the fuses in the front and in the engine bay and all fine. Fuel pump clicks loudly then goes to a whirr but a full turn of the key gets nothing. When you release the key the fuel pump sometimes makes a quicker whirr.

All other electrics working as normal. CDI box is making a noise and the pitch changes when you turn the key fully.

Any ideas what to look for next?
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hot66
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Re: Help with starting issue

Post by hot66 »

You mean the starter isn’t turning the engine over ?
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
markh
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Re: Help with starting issue

Post by markh »

Yes - I should have added that!
Nine One One
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Re: Help with starting issue

Post by Nine One One »

12 Volt battery could be knackered. It may have enough charge to prime the pump and power the CDI, but not enough to turn over engine.
Simple test - turn the headlights on (if dim battery is knackered) if bright and go out when you turn the ignition over, the battery is not holding charge. Even if you charged it, if the plates inside are buckled it will never charge to full capacity, only the bit that is still functioning.
Loz
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Re: Help with starting issue

Post by Loz »

Please don't laugh at me because I haven't looked at my gearbox yet, but does the starter have a bush in the bell housing? (Like the VWs)
If the bush is worn or wearing, this could be the issue.
1970 911t Coupe 2626

"I've started so I'll finish"
markh
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Re: Help with starting issue

Post by markh »

I can get back to the garage tomorrow so I'll try the headlights test and see what's what.
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hot66
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Re: Help with starting issue

Post by hot66 »

check the earth strap too
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
Mike911scrs
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Re: Help with starting issue

Post by Mike911scrs »

Hi Mark

go under the dash and push all the round sockets back in, as the one for the ignition switch has prob worked out with the heat

and the stsrted has its own bush and not in the case like the VW T1,T2,T3,T4, 181

regards mike
Loz
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Re: Help with starting issue

Post by Loz »

Mike911scrs wrote: Thu Aug 08, 2024 9:46 am Hi Mark

......

and the stsrted has its own bush and not in the case like the VW T1,T2,T3,T4, 181

regards mike
👍🏼 Thanks for the info Mike.
1970 911t Coupe 2626

"I've started so I'll finish"
markh
DDK slapper chatter
Posts: 486
Joined: Tue Jul 17, 2007 2:53 pm
Location: Hampshire

Re: Help with starting issue

Post by markh »

Just to wrap this up, checked all the sockets, checked the earths, borrowed some known good batteries and we're back in business!

Two new Bosch betteries ordered.

Thanks for the help!
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hot66
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Re: Help with starting issue

Post by hot66 »

success 8)
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
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