Paul H Posted May 19, 2019 Report Share Posted May 19, 2019 Plus Hi my Vitesse mk2 is still not not running right . She goes through the gears fine and at 30 to 40 mph cruising fine. Then at close to 50mph and 3,000 revs she becomes hesitant as if there is a fuel issue . I remember quite well what Pete told me “ the solution to the problem is not the answer “ so here is my analysis The carbs are cdse with the emission controls blocked off and B5CF needles . I have balanced the carbs with an ear tube and the mixture seems ok , lifting the needle holder a nidge with a flat head screwdriver there is no discernible change in engine revs . The carbs are on max rich now and the pic might suggest I might be able to back off half a turn . The plugs are all roughly the same colour though need a longer run to confirm this before I change the mixture . The pic was taken after just 10 min run so imo not a true picture , but to show there doesn’t seem to be a duff plug My thoughts in line with a previous post suggested the problem was fuel related / lean mixture so the only other thing to try was to revert to the original engine mounted fuel pump as I had converted to a Huco pull pump in the engine bay . The change back made no difference other than the engine needs an additional tug to get started due to the Huco electric pump . With the Huco she will start on second tug and then first time when she is warm. So if it’s not fuel it must be electrics The Distributor is a new Delco with Accuspark ignition . I can change back to Lucas with traditional points Try another coil Replace the spark plugs Change the HT leads As to timing the PO added white marks on the pully and I’m running at 2 to 3 degrees more advanced than the white line The petrol is Tesco premium , recent purchase What should I try first and will make one change at a time so I can isolate the problem I would add that the engine was faultless to a T last year with 3k miles including 1600 miles round Ireland . The setup for last year was as current except for Lucas plus points for part of the time and Accuspark for the remaining . Plus the plugs are gapped at 30 tho now due to electronic ignition Any thoughts and input welcomed Link to comment Share on other sites More sharing options...
dave.vitesse Posted May 19, 2019 Report Share Posted May 19, 2019 My own experience of using 150CDSE carbs on the Mk2 was over a lack of bit in the throttle. Not a flat spot more like a flat performance. I put the standard 150CDS carbs on and it woke the engine up. The only thing I can put it down to was the needle profile gave a weak mixture, but the plugs looked OK. That aside maybe check the emission valve, oil in the dashpots and try a different brand of fuel. It difficult to come up with anything you haven't already covered. Dave Link to comment Share on other sites More sharing options...
Waynebaby Posted May 19, 2019 Report Share Posted May 19, 2019 I had a "soft" misfire on my GT6 which I traced to the incorrect setting of the spring "blade" on top of the Delco rotor arm. If it isn't set high enough it doesn't make proper contact with the dizzy cap centre electrode. This may not be your problem, but it is a simple enough check. I've attached a picture showing the dimension you're looking for Wayne Link to comment Share on other sites More sharing options...
Anglefire Posted May 19, 2019 Report Share Posted May 19, 2019 If it were me, I'd put it back to standard points and re-gap the plugs to 25thou (Or standard if not 25!) Are the leads holding onto the end of the spark plugs ok? I ask because I think that was one of my issues in that the rubber boot over the plug was tending to spring back and hence the spark had to jump twice! Link to comment Share on other sites More sharing options...
dave.vitesse Posted May 19, 2019 Report Share Posted May 19, 2019 Now theirs a memory jogger from Wayne. Thanks. The float chamber valves can stick, not fully closed, causing flooding if the car hasn't been unused for a while. If there is a strong smell of petrol around the carbs and or fuel is found in the air cleaners then it's flooding. Not an uncommon problem on carbs that have been standing. You can try before stripping down the carbs removing the fuel pipe and blasting out the valve with WD40. Dave Link to comment Share on other sites More sharing options...
Paul H Posted May 19, 2019 Author Report Share Posted May 19, 2019 I’ve stripped the carbs and the float valves are working fine with the float set at 18mm Paul Link to comment Share on other sites More sharing options...
poppyman Posted May 19, 2019 Report Share Posted May 19, 2019 Hi Paul, i see you are using NGK plugs. There has been discussion on here as to how good they are?? I have them in one of my car's without problem, but they are nos not recent purchase. Might be worth a try? Tony. Link to comment Share on other sites More sharing options...
Paul H Posted May 19, 2019 Author Report Share Posted May 19, 2019 7 minutes ago, poppyman said: Hi Paul, i see you are using NGK plugs. There has been discussion on here as to how good they are?? I have them in one of my car's without problem, but they are nos not recent purchase. Might be worth a try? Tony. Hi Tony would a duff plug cause the problem ? Paul Link to comment Share on other sites More sharing options...
Pete Lewis Posted May 19, 2019 Report Share Posted May 19, 2019 Plugs...life and soul of the engines performance Those plugs look somewhat sooty And it seems any plugs looking a bit off just dont work well , these days If you read the spark plug post its beginning to add up to ro what a number of us are finding And add when theres a problem under combustion pressures all hell breaks loose Pete Link to comment Share on other sites More sharing options...
NonMember Posted May 19, 2019 Report Share Posted May 19, 2019 1 minute ago, Pete Lewis said: And add when theres a problem under combustion pressures all hell breaks loose Absolutely! Around the turn of the millennium, I had a VW Passat (5-cyl 2L injection - a nice motor). It ran superbly until my local garage, being very helpful, "re-tuned it" (i.e. retarded the ignition) for unleaded, since 4* was about to disappear. After that it suffered a truly horrid misfire if I tried to accelerate from 30 in 4th. I put the ignition back to the 4* setting and it ran beautifully again. The reason was that the whole ignition system was a little past its best, so the spark was a tiny bit weak. In 4* tune that wasn't a problem but 3deg extra retard meant, under those high load/low speed conditions, the in-cylinder pressure at the point of ignition was just a bit too high for a reliable spark. Link to comment Share on other sites More sharing options...
daverclasper Posted May 19, 2019 Report Share Posted May 19, 2019 Could you run it for a while at the hesitant stage, then do a plug chop. It might show wetter/different colour, plug ( if ignition related from the segments of the dizzy cap to the plugs)/or 3 plugs, if one carb related). could be way off with this, just an idea. Dave Link to comment Share on other sites More sharing options...
Paul H Posted May 19, 2019 Author Report Share Posted May 19, 2019 Thanks for all your replies. I will try a new set of plugs to see if that sorts the issue . If it doesn’t run the vitesse at 40 mph for 20 mins and check the plugs . Then run the vitesse at 50 mph for a short period and see if the plug colour changes . I will also accelerate through the 50 mph to see if it is a flat spot . If this achieves nothing change the distributor to Lucas with points Thanks again for your input Paul Link to comment Share on other sites More sharing options...
poppyman Posted May 19, 2019 Report Share Posted May 19, 2019 3 hours ago, Paul H said: Hi Tony would a duff plug cause the problem ? Paul Hi Paul, yes duff plug would cause the problem.... I would try a different make of plug first and see if the problem goes? If it does you know for sure what the problem was..... Try loads of things at once and you wont know what the main cause was, so dont worry to much on the plug colour at this stage. Tony. Link to comment Share on other sites More sharing options...
Paul H Posted May 31, 2019 Author Report Share Posted May 31, 2019 UPDATE , changed the plugs , ht leads and the problem is still there though better defined as follows She starts fine drives well on the flat at 40 mph ish then on my test route of 4 miles there is a long drag of a hill about 0.5 mile long . In the past I’ve been able to cruise up the hill with no issues at 60mph with or without overdrive now as soon as I hit the hill at 3k in 4th I get the start of the engine being “not happy “ and the engine faltering begins and clear signs something is wrong . After the hill it’s back to normal but keeping speeds to about 45 mph as the test run is on local roads . So where can I look to find the issue Paul Link to comment Share on other sites More sharing options...
JumpingFrog Posted May 31, 2019 Report Share Posted May 31, 2019 13 minutes ago, Paul H said: UPDATE , changed the plugs , ht leads and the problem is still there though better defined as follows She starts fine drives well on the flat at 40 mph ish then on my test route of 4 miles there is a long drag of a hill about 0.5 mile long . In the past I’ve been able to cruise up the hill with no issues at 60mph with or without overdrive now as soon as I hit the hill at 3k in 4th I get the start of the engine being “not happy “ and the engine faltering begins and clear signs something is wrong . After the hill it’s back to normal but keeping speeds to about 45 mph as the test run is on local roads . So where can I look to find the issue We had something similar, but a bit more intermittent, seemingly hot weather exacerbated the problem (we were in Iran and it was 40-45c!). Although it'd also start backfiring out the carb.Of course after fiddling around with things the problem would go away for an hour or so. I was convinced it was fuel vaporisation at the time. It turned out to be a dodgy low tension lead (bad crimp) from the dizzy to the coil. I'd be tempted to change it as a matter of elimination. Although maybe this problem is perhaps more likely on a 4-cylinder with the coil on the bulkhead. David 1 Link to comment Share on other sites More sharing options...
Paul H Posted May 31, 2019 Author Report Share Posted May 31, 2019 2 minutes ago, JumpingFrog said: We had something similar, but a bit more intermittent, seemingly hot weather exacerbated the problem (we were in Iran and it was 40-45c!). Although it'd also start backfiring out the carb.Of course after fiddling around with things the problem would go away for an hour or so. I was convinced it was fuel vaporisation at the time. It turned out to be a dodgy low tension lead (bad crimp) from the dizzy to the coil. I'd be tempted to change it as a matter of elimination. Although maybe this problem is perhaps more likely on a 4-cylinder with the coil on the bulkhead. David Im running a Delco with Accuspark ignition - I will swop over to the Lucas 22d? with points to see if that makes a difference Paul Link to comment Share on other sites More sharing options...
dave.vitesse Posted May 31, 2019 Report Share Posted May 31, 2019 Could be lack of fuel. One of the locals had a similar problem and it came down to the needle float chamber valves in the carbs sticking. We cleaned the valves and opened up the float gap by a small about. It got rid of the problem. Maybe ? Dave 1 1 Link to comment Share on other sites More sharing options...
Paul H Posted May 31, 2019 Author Report Share Posted May 31, 2019 3 minutes ago, dave.vitesse said: Could be lack of fuel. One of the locals had a similar problem and it came down to the needle float chamber valves in the carbs sticking. We cleaned the valves and opened up the float gap by a small about. It got rid of the problem. Maybe ? Dave Thanks Dave I’ve had issues before with float valves so will check again and check float valve clearance which should be 18mm . If this is the cause will the spark plug colour give a clue as to which carb . I will check both though Thanks Paul Link to comment Share on other sites More sharing options...
johny Posted May 31, 2019 Report Share Posted May 31, 2019 I see in the original post the timing is 'set 2 - 3 degrees more advanced than the white line' and I wonder why this is? Presumibly the white line was marked by the previous owner to indicate the standard timing position to use a strobe and if correct I cant see that it should ever be set more advanced than that. Normally you set the timing to this point and then retard it progressively to get any knocking to an acceptable level.... 1 Link to comment Share on other sites More sharing options...
Paul H Posted May 31, 2019 Author Report Share Posted May 31, 2019 4 minutes ago, johny said: I see in the original post the timing is 'set 2 - 3 degrees more advanced than the white line' and I wonder why this is? Presumibly the white line was marked by the previous owner to indicate the standard timing position to use a strobe and if correct I cant see that it should ever be set more advanced than that. Normally you set the timing to this point and then retard it progressively to get any knocking to an acceptable level.... Thanks Johnny hadn’t give this a thought I do this change first as it’s the easiest ! I did advance because this was optimum tickover when moving distributor Many thanks Paul Link to comment Share on other sites More sharing options...
johny Posted May 31, 2019 Report Share Posted May 31, 2019 I know its a pain but if it hasnt been done recently I would also recommend a compression and valve tappets adjustment check so that they can be discounted..... Link to comment Share on other sites More sharing options...
JohnD Posted May 31, 2019 Report Share Posted May 31, 2019 Paul, I note your original comment, and johny's, on setting the timing extra advanced. I presume this is by the timing marks on the front pulley. It is possible, I've seen it, for that outer ring, the damper, to slip round on the hub, so that the timing marks become a delusion. If that happens, the damper become ineffective too. To check, find true TDC and see if it coincides with the marks on the pulley. Take out No.1 plug, position the crank about TDC, and put a long screwdriver in the plug hole, so that it sits on the piston top and sghows its movements. Now adjust the position of the crank - a large spanner or socket on the hub bolt will turn it - to find true TDC. It's fiddly, the piston moves more and more slowly as it approaches TDC and will stop over at least one degree at the critical point. Now see if that agrees wth the pulley marking. Good luck! John 1 Link to comment Share on other sites More sharing options...
daverclasper Posted May 31, 2019 Report Share Posted May 31, 2019 (edited) I'm am no means an expert by any means on all the differentials on how, even our old cars are running, though with twin carbs, looking at the 3 seperate plugs can give an indication of separate, carb versus ignition issues. I THINK. Dave Edited May 31, 2019 by daverclasper Link to comment Share on other sites More sharing options...
dougbgt6 Posted May 31, 2019 Report Share Posted May 31, 2019 I notice you've got CDSEs, what condition are the rubber diaphragms in? Uncle Pete calls them elephant condoms. They should be soft and supple. There could also be a fuel line blockage issue, rubber slivers in the carb reservoir inlet or sludge in the fuel line. Doug Link to comment Share on other sites More sharing options...
Paul H Posted May 31, 2019 Author Report Share Posted May 31, 2019 8 minutes ago, dougbgt6 said: I notice you've got CDSEs, what condition are the rubber diaphragms in? Uncle Pete calls them elephant condoms. They should be soft and supple. There could also be a fuel line blockage issue, rubber slivers in the carb reservoir inlet or sludge in the fuel line. Doug Hi Doug the CDSE’s are in good order as in the past have suffered with slivers , sludge from fake R9 tubing, sticking float valves etc though I will be checking the float valves again plus float height just in case . On the list is to compare the plugs as suggested in your recent post - Thanks Paul Link to comment Share on other sites More sharing options...
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