Fuel issues with SE5a

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ScimiTom
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Fuel issues with SE5a

Post by ScimiTom » Tue Jul 17, 2018 8:07 pm

Well, Boffin is back on the move. I'm not 100% sure what the cause was - only that the solution turned out to be none of the above!

I didn't hotwire or look at the carb, but instead opened up the distributor. I fitted a new contact breaker and checked the points gap was at 25 thou. I noticed a slight tear on the rubber connector for the vacuum pipe running from the distributor to the carb. A tiny jubilee clip sealed this back up, and 'hey, presto' - the car was happy again. The small changes I made seemed to have raised the idle speed to about 1,100 rpm, so this was adjusted down to 800. Took the car out for a 10-mile run and all seems well once more. I can only guess that a slight air leak in the vacuum pipe was the issue.

Thanks for all the pointers, everyone. :)


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

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ScimiTom
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Fuel issues with SE5a

Post by ScimiTom » Sun Aug 12, 2018 9:36 pm

Well, that was all too good to be true, of course...

The symptoms returned and I'm back to square one with the car. Here's what has been done:
1. Hotwiring - made no difference
2. Different coil used - made no difference
3. Timing checked
4. Spark strength checked
5. Distributor checked
6. Connection from starter solenoid (leading to coil) tightened up

After step 6, the car started and ran fine for 10-15 minutes, then the stuttering returned (especially around 20-30mph), fully cutting out when slowing down on an upwards incline, and now a rev counter needle which flaps about all over the place.

I just can't figure out if this is a fuelling issue or an electrics issue.

I plan to replace the condenser and coil (it did seem to get very hot), then check the carb, but any other tips are welcome...

Thanks
Tom


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

mattscimmy
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Fuel issues with SE5a

Post by mattscimmy » Wed Aug 15, 2018 9:18 pm

I'm in exactly the same situation as you Tom.
Limited time to play and a car which only splutters / stalls when hot. Nothing I've done seems to make any difference😡. Going to drain all the fuel tomorrow and try fresh 97octane. Good luck with yours.



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ScimiTom
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Fuel issues with SE5a

Post by ScimiTom » Wed Aug 15, 2018 10:18 pm

mattscimmy wrote:
Wed Aug 15, 2018 9:18 pm
I'm in exactly the same situation as you Tom.
Limited time to play and a car which only splutters / stalls when hot. Nothing I've done seems to make any difference😡. Going to drain all the fuel tomorrow and try fresh 97octane. Good luck with yours.
Yes - frustrating, isn't it? Best of luck sorting yours. I'll be having another look at mine tomorrow. Pommy's 12-page thread on this exact issue may be worth a read - in his case it was ultimately a wiring issue: http://www.scimitarweb.co.uk/sgwrs/view ... &start=165


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

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Fuel issues with SE5a

Post by scimjim » Wed Aug 15, 2018 10:23 pm

There was absolutely no visible faults on my dizzy cap, but after being recovered from Brighton on the Sunday, I replaced it and drove to Le Mans and back (in July) without a problem.


Jim King

SECURE DRY STORAGE FOR YOUR SCIMITAR

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
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Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), 1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Fuel issues with SE5a

Post by mattscimmy » Sat Aug 18, 2018 3:31 pm

Swapped distributors fomoco for Bosch. Going fine now.



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ScimiTom
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Fuel issues with SE5a

Post by ScimiTom » Sat Aug 18, 2018 7:50 pm

Great news, Matt - glad you're up and running again...

...As am I! After replacing the coil and the condenser, all is well once more. I haven't ascertained which of the two was at fault, but I'm just glad that in the end it was a relatively simple fix. So, as is often the case with Scimitars, it came down to an electrical issue in the end!


Current: 'Boffin' (1971 SE5a)
Previous: 'Sunshine' (1980 SE6b)

mattscimmy
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Fuel issues with SE5a

Post by mattscimmy » Sun Aug 19, 2018 5:24 pm

That's great Tom :D .



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