rough running / non starting |
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rough running / non starting |
JFG |
Sep 2 2018, 11:48 AM
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#1
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
The other day i drove my car for the first time, properly, and did a six or so mile loop just about.
The car started popping and losing power momentarily and i just made it back onto the driveway. It was fine when cold but when it got hot the above started. This morning i turned the key and it fired up straight away so i pulled it out of the garage for a check over. I took the plugs out, they were slightly sooty and gaps are at 0.60mm on ngk bp6es iirc. When it was back together the bloody thing would not start at all. Lost my cool, nearly, and pushed it back in the garage. Tonight i tested the coil and there is a good blue spark on the test plug. so i'm thinking the coil and electric ignition module in the distributor are fine. My fuel pump is up under the tank and that is running no problems. My next check is to see if fuel is getting to the carbs, i find it odd that despite the pump running and plenty of fuel the plugs were not flooded or even wet in any cylinder. My first thought when it limped home was fuel evaporation but i'm not so sure now. More checks to follow (IMG:style_emoticons/default/headbang.gif) |
jarodswordmaster |
Sep 2 2018, 09:42 PM
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#2
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Newbie Group: Members Posts: 8 Joined: 31-August 18 From: Ignacio Member No.: 22,447 Region Association: Southwest Region |
check your cylinder head temperature sensor. Mine was disconnected and the engine would hardly run it was running so rich.
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JFG |
Sep 2 2018, 11:27 PM
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#3
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
i'm running twin 40idf on a 1.7 with an sv30 distributor (i think will check that code)
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porschetub |
Sep 2 2018, 11:33 PM
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#4
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Advanced Member Group: Members Posts: 4,728 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
No he has carbs,so that makes no difference,is the engine in good tune electrically ?,usual culprits,dizzy cap,rotor,plug leads and is the timing spot on ?.
If the engine hasn't run for a while check the fuel filter and pull the idle jets and make sure they aren't blocked,check air cleaners are clean @ the same time,might pay to check your fuel pressure and clean the suction filter in your tank,there is a bunch of other things but best to start with the above, (IMG:style_emoticons/default/beerchug.gif) . |
JFG |
Sep 4 2018, 12:35 PM
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#5
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
only had 5 minutes spare today but have checked fuel and it is flowing well.
i'll take the top off one carb tomorrow and check inside. these are brand new (not chinese) idf's so wouldn't think they're faulty. |
jcambo7 |
Sep 4 2018, 01:25 PM
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#6
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Senior Member Group: Members Posts: 1,691 Joined: 24-December 08 From: Graham, WA Member No.: 9,867 Region Association: Pacific Northwest |
Check your points gap also and makes sure it is gapped correctly and your timing
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SierraNevada |
Sep 4 2018, 01:27 PM
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#7
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Newbie Group: Members Posts: 22 Joined: 11-September 15 From: Mammoth Lakes, Ca Member No.: 19,148 Region Association: Southern California |
My crusty fuel lines clogged my webers up. Make sure your lines are new, even the dreaded line that runs the length of the tunnel where the shifter is! Also rebuild your carb or send your injectors to Mr.Injector out in idaho.
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JFG |
Sep 4 2018, 02:07 PM
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#8
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
my carbs & entire fuel line system is brand new. the jets are within range to be fine. the engine ran sweet until the first proper drive.
the distributor has electronic module in it and the test plug is sparking fine. i now have a compression tester to double check that also. the oddest thing is that the plugs are not wet after cranking the engine over. |
jcambo7 |
Sep 4 2018, 02:12 PM
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#9
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Senior Member Group: Members Posts: 1,691 Joined: 24-December 08 From: Graham, WA Member No.: 9,867 Region Association: Pacific Northwest |
Check fuel filters and your fuel tank strainer if you haven't yet. I and other members have had issues with electronic points modules. If you have points and can switch back to them you could truly eliminate that as the cause.
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JFG |
Sep 5 2018, 11:32 AM
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#10
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
All plugs are firing fine on their respective leads.
The compression test is as follows 1 8 bar 2 8 bar 3 7 bar 4 7 bar Managed to get it started briefly, it was popping & cut out. Took off the carb on 3 + 4 and it had crap in the bottom. I stripped and cleaned that. Checked my float level and it was 25mm open, 10mm closed. Not sure how that has happened but I've put it back to 10 & 32 respectively. One carb done one to go. I checked the tank again and the strainer sock has fallen inside leaving the outlet exposed. Causation found even though I have a filter just before the pump. Going to fit a glass or metal one in the engine bay before the t piece. I haven't fired it up yet but will hopefully do it tomorrow when I get a new filter. |
JFG |
Sep 7 2018, 10:18 AM
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#11
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
i fitted the new inline filter and flushed old petrol from the lines past it
i did get a couple of times where it tried to fire up but nothing more. so i'm now stumped. i have spark, compression & fuel & 12v at the coil however when i take the middle ht / cap lead out of the dizzy (from the coil) i get no spark at any distance, when i put a spark plug in i get one spark then nothing. i do get spark at the plugs though!!! could this be ignition switch? |
marksteinhilber |
Sep 7 2018, 11:42 AM
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#12
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Member Group: Members Posts: 229 Joined: 18-October 12 From: Foothill Ranch, CA 92610 Member No.: 15,057 Region Association: Southern California |
i fitted the new inline filter and flushed old petrol from the lines past it i did get a couple of times where it tried to fire up but nothing more. so i'm now stumped. i have spark, compression & fuel & 12v at the coil however when i take the middle ht / cap lead out of the dizzy (from the coil) i get no spark at any distance, when i put a spark plug in i get one spark then nothing. i do get spark at the plugs though!!! could this be ignition switch? The center post or coil lead connection at the distributor cap may have a problem letting the spark get to the rotor, and then all the way to the plugs. Rotors with an internal resistor are known to go bad. If you don't have a good spark indicated at each and every plug consistently, then check each ignition component from the coil to the plugs, i.e. full tune up, points, wires, rotor, cap condenser, etc. |
Mikey914 |
Sep 7 2018, 01:42 PM
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#13
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The rubber man Group: Members Posts: 12,729 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
I recently had a similar issue I’ll share.
Lost my 3 port pump, so had it replaced as I didn’t have time to do it. Got the car home (about 2 miles), and in the garage. Went to go drive it and it run for a few seconds before it sputtered to a stop. Tried to restart waiting a few seconds and a quick pump to the throttle. Fired up and sputtered to a stop again. I could hear the pump run and stop once pressurized. So thinking fuel was not an issue checked the intake, spark, MPS, and CHT. All looked good. Gave up and towed it to Allen down at A&P in Portland. Turned out to be a easy fix. Turned out that the fuel line under the tank was too long and had gotten pinched. Not completely, but enough it wouldn’t keep up. Basics Air Fuel Spark It’s usually fuel related in one form or another. That’s why many went to carbs. Check the lines, filters, and if there was crud that washed though it could be jets. And yes carbs help here. |
JFG |
Sep 10 2018, 02:26 AM
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#14
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
The fuel lines have been checked and there are no links. I have good flow at both carbs.
My new b6es NGK spark plugs will be here today and as a precaution I ordered another coil too. The resistance measured was 2.2 ohms. It's a 3 ohm coil operating electronic ignition. It's also 1 month out of warranty (IMG:style_emoticons/default/headbang.gif) |
BeemerSteve |
Sep 10 2018, 09:20 AM
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#15
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Member Group: Members Posts: 239 Joined: 2-September 15 From: Van Zandt, Wa Member No.: 19,123 Region Association: Pacific Northwest |
If you are running points and condenser I'd check replacing the condenser. This had happened to me once changed out the condenser problem solved.
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JFG |
Sep 10 2018, 09:39 AM
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#16
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
this is now frying my brain.
fitted the new coil and b6es plugs. i'm getting a better spark than before. however it still won't freaking start. i have compression and i have fuel into the carbs (these have been stripped and cleaned even though they were brand new spanish idf's) the tank is out and the pump has been removed. there was some fine crap that came out of the filter. i'm going to get fresh petrol and run the pump directly from the can but i'm not confident. the dizzy is running an electronic piece instead of points and its an svda 34 unit that i bought as a bundle. any new ideas? |
JFG |
Sep 12 2018, 12:33 PM
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#17
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
over the last 2 days i've gone through everything again. i even took the tank out and put the pump at the back and ran from fresh fuel in a can.
i finally got it to run, albeit lumpy and fast, but it's running. i was about to dial the carbs & timing in when it threw the fan belt. so that's next. my suspicion is their was maybe some crud in a carb that i may have missed first time around. |
Localboy808 |
Sep 17 2018, 09:57 PM
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#18
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Member Group: Members Posts: 185 Joined: 17-July 16 From: Palmdale, Ca Member No.: 20,194 Region Association: None |
over the last 2 days i've gone through everything again. i even took the tank out and put the pump at the back and ran from fresh fuel in a can. i finally got it to run, albeit lumpy and fast, but it's running. i was about to dial the carbs & timing in when it threw the fan belt. so that's next. my suspicion is their was maybe some crud in a carb that i may have missed first time around. Any resolution? |
JFG |
Sep 18 2018, 06:55 AM
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#19
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
i had some time on it today. the tank is back on with a new (old) filter sock in it. i have new filter before the pump and another filter before the carbs.
when i stripped the carbs first i didn't realise there was a small filter in the chamber where the inlet is on each carb. once i cleaned these there was no more crap in the pipes or carbs. lesson learnt about proper filtering the fuel system. the belt is back on and the car fired up straight away. it kicked straight in and idled at 1400 revs. so once it's back on the ground i'll properly adjust the carbs & timing. |
JFG |
Sep 20 2018, 02:21 AM
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#20
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Senior Member Group: Members Posts: 686 Joined: 7-April 16 From: Wales Member No.: 19,869 Region Association: None |
another look at the running and i've got idle down to 1000rpm. the engine revs up nicely (although the rev gauge is a little eratic) but on wind down it pops a little from the exhaust. i've isolated the problem to cylinders 1&2.
when the rain stops i'll get out and drive it and see what happen, for now though it's good hear it running (IMG:style_emoticons/default/biggrin.gif) |
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