but wait, there's more ... S Type questions
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From: nsw
but wait, there's more ... S Type questions
I am writing this while listening to an 11yo beginner practicing trumpet so forgive any imperfections...
OK, first question concerns timing, richness and carbies. My 1964 s type runs rich at idle and pings at moderate engine speed under acceleration.
The local mechanic (not a jag or even british car specialist) reckons its probably grit in the cars. He seemed pretty confident. He pointed out to me that it was running rich (which I did realise due to the black smoke coming out of the exhaust). I then pointed out that it was pinging a lot. He smiled and quite confidently said that the carbs were probably dirty.
Added to this is the fact that the car at the moment does not have a filter element in the glass bowl of the fuel filter and there was a fair bit of fine black muck in the bottom of it when I checked a short time ago.
The PO explained that it needed a new filter but there werent any in stock where he tried to source them from so advised me to keep an eye on the glass bowl for dirt. He also said he had timed it recently. I have pretty substantial faith in the honesty and knowledge of the PO.
So the questions are:-
1) does the "dirty carbs" opinion sound reasonable
2) If answer to 1 is "Yes"; then can carbs clear on their own, is there a "carburettor cleaner" that might help, do they need an overhaul and is it difficult to do?
3) if "No" then what other possibilities would give those symptoms (richness at idle and pinging at speed)?
Obviously I intend to source a fueld filter element ASAP.
Thanks in advance for any thoughts/ideas.
Cheers
OK, first question concerns timing, richness and carbies. My 1964 s type runs rich at idle and pings at moderate engine speed under acceleration.
The local mechanic (not a jag or even british car specialist) reckons its probably grit in the cars. He seemed pretty confident. He pointed out to me that it was running rich (which I did realise due to the black smoke coming out of the exhaust). I then pointed out that it was pinging a lot. He smiled and quite confidently said that the carbs were probably dirty.
Added to this is the fact that the car at the moment does not have a filter element in the glass bowl of the fuel filter and there was a fair bit of fine black muck in the bottom of it when I checked a short time ago.
The PO explained that it needed a new filter but there werent any in stock where he tried to source them from so advised me to keep an eye on the glass bowl for dirt. He also said he had timed it recently. I have pretty substantial faith in the honesty and knowledge of the PO.
So the questions are:-
1) does the "dirty carbs" opinion sound reasonable
2) If answer to 1 is "Yes"; then can carbs clear on their own, is there a "carburettor cleaner" that might help, do they need an overhaul and is it difficult to do?
3) if "No" then what other possibilities would give those symptoms (richness at idle and pinging at speed)?
Obviously I intend to source a fueld filter element ASAP.
Thanks in advance for any thoughts/ideas.
Cheers
Veteran Member
Joined: Jul 2012
Posts: 5,546
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From: Llandudno, Cape Town, South Africa
I am writing this while listening to an 11yo beginner practicing trumpet so forgive any imperfections...
OK, first question concerns timing, richness and carbies. My 1964 s type runs rich at idle and pings at moderate engine speed under acceleration.
The local mechanic (not a jag or even british car specialist) reckons its probably grit in the cars. He seemed pretty confident. He pointed out to me that it was running rich (which I did realise due to the black smoke coming out of the exhaust). I then pointed out that it was pinging a lot. He smiled and quite confidently said that the carbs were probably dirty.
Added to this is the fact that the car at the moment does not have a filter element in the glass bowl of the fuel filter and there was a fair bit of fine black muck in the bottom of it when I checked a short time ago.
The PO explained that it needed a new filter but there werent any in stock where he tried to source them from so advised me to keep an eye on the glass bowl for dirt. He also said he had timed it recently. I have pretty substantial faith in the honesty and knowledge of the PO.
So the questions are:-
1) does the "dirty carbs" opinion sound reasonable
2) If answer to 1 is "Yes"; then can carbs clear on their own, is there a "carburettor cleaner" that might help, do they need an overhaul and is it difficult to do?
3) if "No" then what other possibilities would give those symptoms (richness at idle and pinging at speed)?
Obviously I intend to source a fueld filter element ASAP.
Thanks in advance for any thoughts/ideas.
Cheers
OK, first question concerns timing, richness and carbies. My 1964 s type runs rich at idle and pings at moderate engine speed under acceleration.
The local mechanic (not a jag or even british car specialist) reckons its probably grit in the cars. He seemed pretty confident. He pointed out to me that it was running rich (which I did realise due to the black smoke coming out of the exhaust). I then pointed out that it was pinging a lot. He smiled and quite confidently said that the carbs were probably dirty.
Added to this is the fact that the car at the moment does not have a filter element in the glass bowl of the fuel filter and there was a fair bit of fine black muck in the bottom of it when I checked a short time ago.
The PO explained that it needed a new filter but there werent any in stock where he tried to source them from so advised me to keep an eye on the glass bowl for dirt. He also said he had timed it recently. I have pretty substantial faith in the honesty and knowledge of the PO.
So the questions are:-
1) does the "dirty carbs" opinion sound reasonable
2) If answer to 1 is "Yes"; then can carbs clear on their own, is there a "carburettor cleaner" that might help, do they need an overhaul and is it difficult to do?
3) if "No" then what other possibilities would give those symptoms (richness at idle and pinging at speed)?
Obviously I intend to source a fueld filter element ASAP.
Thanks in advance for any thoughts/ideas.
Cheers
Tim,
If your fuel filter has the fine filter gauze above the glass bowl then it does not really need a visible filter. Then some cars had the "burnt cake" (metallic composite?) filter in the bowl & some a yellow pleated paper filter that collects dirt internally as I understand it.
Re pinging/knock. Aus has good fuel so that should not be an issue. First thing to do is have advance curve of distributor checked & set timing correctly. High speed knock could mean that the distributor is over advancing. My car has approx 8.5 to 1 CR. Do you know what pistons are fitted to your car? Standard CR's were 7 to 1, 8 to 1 & 9 to 1. Most heads today have been shaved.
Correct distributor is a Lucas 22D6 41063A
I have no pinging with static timing set at 7 deg BTDC. 95 RON gas/petrol at coast ~ distributor rebuilt & on spec. New clean engine with no piston or combustion chamber deposits so no incandescent hot spots.
Do yourself a big favour. Strip the carbs. Clean them thoroughly. Fit new diaphragms/jets & make sure you have TL needles in them. Set float levels etc properly & go through the correct tuning procedure.
Also make sure your AED is not sticking. (Automatic enrichment device on thermo carbs)
Buy yourself a copy of.
Last edited by Glyn M Ruck; Oct 14, 2019 at 06:06 AM.
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