David Mirylees Posted August 24, 2006 Share Posted August 24, 2006 Help! Short while ago listed a problem with the 45's on my 2 litre zetec where barrel No.3 was impossible to set an idle. Took the easy way out - thanks to my old dear - and got hold of a new pair of carbs from Gower & Lee. I now have a super idle and a very quick car at full bore but it's almost impossible to drive at any steady revs from 1200 to 3000 (which is where I spend most of my in traffic) as it misfires like hell. It is also almost impossible to adjust the idle screws as there is little discernible rev change, so they are out of the box at 2.5 turns. The balance between the carbs is showing as spot on using the crypton gauge and the butterflies are in identical positions when looking at the progression holes. There is also no hesitation when blipping the throttle so I assume the balance is OK. I also changed the ECU as the (very) old unit wouldn't recognise the latest weber thottle pot. The computer shows the throttle to be working correctly and the ECU supplier assures me that my problem is with the carbs. Unfortunately (for me) the carb bods answer is "take it on a rolling road". Not that easy and not what I expected (the carbs came jetted exactly as my originals) as I have managed for the last 36+ years on my own. Has anyone had and sorted a similar problem? What can I adjust next? Aplogies for the tome - just trying to think of everything :-( Cheers david Link to comment Share on other sites More sharing options...
millsn Posted August 24, 2006 Share Posted August 24, 2006 Might be worth looking at the exact positions of your progression holes relative to another zetec engined car. My old carbs had four holes but clearly needed five as is general wisdom. With four the car still had an annoying cough as I opened the throttles so I eventually stumped for TBs. If you have 3 holes it probably isn't sufficient and I imagine you'll be running rich to cover the poor progression. Seems odd though that you can't manage the mixture by feeling for the revs changing. Link to comment Share on other sites More sharing options...
millsn Posted August 24, 2006 Share Posted August 24, 2006 Just a thought, Idid have a similar problem once. One of the wires that feeds the coil had come loose within the plug that connects to the coil itself. Give your wires a rattle, if they fall out you'll know. Link to comment Share on other sites More sharing options...
David Mirylees Posted August 24, 2006 Author Share Posted August 24, 2006 The new carbs have the 5 progression holes - actually the missing band is probably just when the butterflies clear these. Coil wires OK - I crimped them with great care to ensure all was OK.......... Looks like the rolling road is the only option david Link to comment Share on other sites More sharing options...
EFA Posted August 26, 2006 Share Posted August 26, 2006 David, Speak to Jimmy the Fish. He used to do a mod to the progression holes to cure whats sounds to be exactly the problem you describe, on the Zetec. K2RUM - The car of two halveswith a hole in the engine Link to comment Share on other sites More sharing options...
David Mirylees Posted August 29, 2006 Author Share Posted August 29, 2006 Paul Turner told me that he had a similar (but opposite) problem and different emulsion tubes made the difference. I have asked Gower & Lee to let me have a trial of the recommended F4's (I have F16's fitted) I have tried many, many times over the last few weeks to contact James Whiting on the phone - I keep getting an answering machine - anyway, have actually left a message today so may get a response (James actually supplied the original, now scrap. carbs!!!) Thanks all for your help - I'll post the results and hopefully the cure if and when it happens (for the sake of future searches). I have now been 7-less for the longest time in more than 30 years - what a ******** up :-( cheers david Link to comment Share on other sites More sharing options...
allen Posted August 29, 2006 Share Posted August 29, 2006 Dave, I remember that James W said on my twin 40s - 1800 zetec conversion, that 5 progression holes were too many and one would need to be blocked up - wasn't necessary as carbs turned out to only have 4. Think I's have had the original carbs re-built Good luck allen Link to comment Share on other sites More sharing options...
David Mirylees Posted August 29, 2006 Author Share Posted August 29, 2006 The whole fiasco has cost so much now I think I would have been better paying a bit more and going for the complete injection system :-) Unfortunately rebuilding the original carbs was not a good idea as they had been problematic from the word go. Although supplied as a pair, one was a 45DCOE9 and the other a 45DCOE16 and even the choke levers worked in opposite directions (need a choke sometimes to start in mid winter as the car - until now - was my everyday transport). Initially, after a blat, the things would cut-out having run out of fuel but I sourced that to massively out of adjustment float levels. Gower & Lee told me that they were scrap and that they had never seen such a twisted spindle on my rear carb!!!!! Really thought buying new was the most simple and effective way forward - I am also hearing (now!!) that some chaps have horror stories with these new Spanish built units (my ECU supplier told me that he had a new pair on a customers engine that one barrel wouldn't work - eventually found, after removing some blanking plug, that there was swarf completely blocking a passageway.................... Ho hummmmm what do they say about hindsight................ david Link to comment Share on other sites More sharing options...
David Mirylees Posted October 24, 2006 Author Share Posted October 24, 2006 Just to cover the whole sorry sequence of affairs........ Gower & Lee refuse to change the carbs (turns out they are 4 progression hole versions and not the 5's) their advice is that they have many 2.0 zetecs running on the 4 holes trouble free and I should take the car to a rolling road. Now done that (another £450) and the engine is as bad as ever. Goes like a train when floored but impossible to drive in traffic. Gower & Lee said they would get "recompense from Weber" if I got the rolling road bods to furnish a report. Course the RR bods were/are not keen to do this and state that they can probably get the car sorted if they had it for a week (yeah, and another £1200!!) but no promises. Apparently (source - Weber) the 4 hole versions were developed on behalf of GM but due to pretty well exactly the problems I have been getting, they developed the 5 hole version for the 2.0 Zetec. State of affairs now is when I took the car back to the RR a bright spark at the took the 50F9 slow running jets and opened up the side hole to appx 2mm and, although not perfect, the low end has improved with no popping and backfiring. (luckily they did this for nought as it was embarrassing that they could not improve the car previously on the two days they had previously played with it). Moral #1 If it ain't impossibly broke - don't fix it. Moral #2 Only buy bits like this from the "right" people. This has been an expensive exercise, I can't throw any more cash at it and the sellers really aren't interested in helping. All very annoying as I have been playing with twin carbs for more than 35 years. I really should have been able to fit a new pair of carbs and found - at the least - smooth basic running characteristics, just as I have in the past. EOF Link to comment Share on other sites More sharing options...
Paul Formston Posted October 24, 2006 Share Posted October 24, 2006 Hi Dave if its any consulation when I first fitted my Jenve Throttle Bodys to my 1800 Zetec, the Garage that said they knew how to set them up had it black smoking and doing 10 mpg and charged me £400 for the pleasure, all he was doing was adjusting the injection spray time he didn't know how to adjust the map it was a knight mare, luckerly I found a Bloke with a lap top that used to work for Malcolm Wilsom Motor Sport and he sorted it, Have you tried taking all the jets out and giving the carbs a good blowout with a airline just in case there is any crap in them also try Reving the engine and block each trumpet one at a time to suck any crap though its worth a try Regards Paul Link to comment Share on other sites More sharing options...
Paul Formston Posted October 24, 2006 Share Posted October 24, 2006 Hi Again Dave just a thought are you running a fuel pressure regulator and is it set at the correct pressure Regards Paul Link to comment Share on other sites More sharing options...
robert green Posted October 24, 2006 Share Posted October 24, 2006 I am planning a 2 l zetec conversion, and was planning to stick with my 40's as I had heard that the 45's had been problematic. Has anyone had similar probs with the 40's? How much extra should it cost to convert a carb car to EFI Link to comment Share on other sites More sharing options...
Paul Formston Posted October 24, 2006 Share Posted October 24, 2006 Hi Robert, you will need a high pressure fuel pump and swirl pot for the fuel tank, it may be worth asking Caterham how much a new injection tank and pump is, then you will need a set of Throttle bodys, I got mine from Raceline give Chris a ring but for the Jenvees and the management I think it comes to £1,700 or so but once its set up its great runs realy well just like a modurn car no messing about Regards Paul Link to comment Share on other sites More sharing options...
Jaseb Posted October 24, 2006 Share Posted October 24, 2006 Absolutely no probs running a 2l zetec on 40's IIRC I got my car rolling road tuned for around 150 quid including the change of jets from the old XF,the tuning man keptmy old jets and whatevers as spares forthe next person. It turns out around 160bhp. Link to comment Share on other sites More sharing options...
Tight fart Posted October 24, 2006 Share Posted October 24, 2006 My fuel injected Dunnell Zetec run like a pig, even after going back to them to be mapped! After a change of ECU and a trip to Emerald it's transformed. Not a lot of gain in peak power but at no revs it's drives like a Honda civic and then just climbs. A7 RDP pics here Link to comment Share on other sites More sharing options...
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