Davewillb Posted February 8, 2011 Share Posted February 8, 2011 Hi, My 2.25 petrol series 2a will start easily but will only run with the choke full out and then won't rev and backfires and spits back back through the carb (which is a weber) when you try to rev it - does this sound like a carb problem? This is a 'get it back on the road with an MOT restoration and the budget is tight and I don't have a spare carb to try so a head up on what this is likely to be will save me some dosh hopefully. Cheers, Dave Quote Link to comment Share on other sites More sharing options...
rtbarton Posted February 8, 2011 Share Posted February 8, 2011 It could be a blocked jet, or it could also be the condenser in the dizzy. Maybe as well to check the timing too. Quote Link to comment Share on other sites More sharing options...
Davewillb Posted February 8, 2011 Author Share Posted February 8, 2011 i It could be a blocked jet, or it could also be the condenser in the dizzy. Maybe as well to check the timing too. Thanks, I've got a new condenser so I can try that tomorrow evening and the timing. Cheers, Dave Quote Link to comment Share on other sites More sharing options...
Swifty oh no Posted February 10, 2011 Share Posted February 10, 2011 Mt Weber runs a little rough with the choke out until properly warmed up ( which takes about twice the time my old Zenith did) but nothing that severe. I did have the same problem a while back though and it turned out to be the condenser. Quote Link to comment Share on other sites More sharing options...
RobotMan Posted February 12, 2011 Share Posted February 12, 2011 Sounds like the idler jet is blocked. I haven't run one for years but it's on the inner face of the carb towards the bottom. Simply unscrew it then using a standard bicycle pump pressed against the pointy end , give it a good blast and put it back in. Keep the pump in the motor with you it is handy to have I eventually went back to a Zenith, mainly because the Webber was worn out. I run a 200 Tdi now mind! Quote Link to comment Share on other sites More sharing options...
rtbarton Posted February 12, 2011 Share Posted February 12, 2011 Another way of clearing blocked jets is to remove the air inlet elbow to expose the top of the carb, start the engine and with a leather gloved hand briefly obstruct the inlet. The downside is any carp gets sucked into the engine, but I have used this method in an emergency to get me home. Quote Link to comment Share on other sites More sharing options...
Davewillb Posted February 13, 2011 Author Share Posted February 13, 2011 Well I swapped the condenser this weekend and I can say with confidence it isn't that - spent the rest of Sunday stripping the front hub to replace the oil seal and after I scrapped all the greasy oily crud off I could then see the swivel oil seal had gone as well (the seal retaining ring had almost rusted away - beats me how it did that under all that goo). I'll get back to the engine while I wait for parts for the swivel - thanks for the tips on jet cleaning, the leather glove one sounds good to me - after the work on the swivel I've got a pair of gloves that are well soaked in oily grease, should seal well!! Dave Quote Link to comment Share on other sites More sharing options...
Davewillb Posted February 18, 2011 Author Share Posted February 18, 2011 Latest update is that I've now swapped the carb for another Weber (I was convinced that was the problem) and guess what, no difference at all. I'm wondering about the vacuum advance on the distributor - if this isn't working will it give the sort of symptoms I've got? Haven't been able to check the timing as I haven't got a strobe but may just try tweaking the distributor and see what happends! Dave Quote Link to comment Share on other sites More sharing options...
rtbarton Posted February 18, 2011 Share Posted February 18, 2011 You can get those engines pretty close without a strobe, set the timing statically first and tweak at a fast tickover. I seem to remember something about having to set the timing with the vac advance disconnected, or keep the revs below the point at which it cuts in. Quote Link to comment Share on other sites More sharing options...
matrix1688 Posted February 18, 2011 Share Posted February 18, 2011 You can get those engines pretty close without a strobe, set the timing statically first and tweak at a fast tickover. I seem to remember something about having to set the timing with the vac advance disconnected, or keep the revs below the point at which it cuts in. Yes you do have to time it with the vac disconnected but have a short peice of pipe with one end closed to go on the dizzie while you time it. Quote Link to comment Share on other sites More sharing options...
rtbarton Posted February 18, 2011 Share Posted February 18, 2011 Yes you do have to time it with the vac disconnected but have a short peice of pipe with one end closed to go on the dizzie while you time it. Surely to go on the carb so you don't weaken the mixture? Blocking the dizzy off won't make any difference. It's coming back to me now, disconnect the vac, pipe, but keep the revs below the point the weights kick in? Quote Link to comment Share on other sites More sharing options...
Davewillb Posted February 23, 2011 Author Share Posted February 23, 2011 A bit of progress to report, when I scrapped the oily gunge off the base of the distributor I could see that the clamp is 'well mangled' to the extent that the bolt is bent - I took the distributor off (not easy due to the aforementioned bolt) and straightened it all out. The clamp needs a spot of weld where it is starting to crack due to fatigue but I fitted it all back together loosely(ish) to try it and it started and ran much better -this was luck as I just stuck the distributor back in approx the right position and tried it. I then looked for the timing marks on the front pulley and there aren't any - a quick google revelaed that I should be looking for the plate giving access to the flywheel and lo and behold that's been removed by the previous owner ...... I'm now wondering if I'm following someone else's tracks - so anyway I can have a proper go at setting the timing and see where that gets me. The history of the Landy is that I bought it as a 'garden find' the engine started easily when I got it home last year (with a gravity petrol feed as the pump had packed up) so I've been working on all the other problems since then including rotten bulkhead (see attached!)and seized brakes etc. I thought I'd add the second picture as a testimony to inovative bodging (not mine!). Dave Quote Link to comment Share on other sites More sharing options...
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