chilly Posted January 6, 2009 Report Share Posted January 6, 2009 My TR6 is running twin SU's. A few years ago I had it set up on a rolling road. After setting up the car was 'running-on' a little. I asked the tuner if it could be cured. He said it could easily be cured be disconnecting a rubber tube (I think), he did say there was a slight downside but I can't remember what it was. I've lived with the (intermitant) running-on ever since and, whilst slightly annoying, it hasn't bothered me too much. I am now selling the car and the buyer wants it sorting. My questions are: which pipe/tube is it likely to have been? What would the downside be to disconnecting said tube (if any). Is there any other way round the problem that won't involve disconnecting the pipe? Other facts: The car doesn't need a decoke, the car is fitted with electronic ignition. Appreciate any advice. Cheers Chris Quote Link to post Share on other sites
foster461 Posted January 6, 2009 Report Share Posted January 6, 2009 My TR6 is running twin SU's. A few years ago I had it set up on a rolling road. After setting up the car was 'running-on' a little. I asked the tuner if it could be cured. He said it could easily be cured be disconnecting a rubber tube (I think), he did say there was a slight downside but I can't remember what it was.I've lived with the (intermitant) running-on ever since and, whilst slightly annoying, it hasn't bothered me too much. I am now selling the car and the buyer wants it sorting. My questions are: which pipe/tube is it likely to have been? What would the downside be to disconnecting said tube (if any). Is there any other way round the problem that won't involve disconnecting the pipe? Other facts: The car doesn't need a decoke, the car is fitted with electronic ignition. Appreciate any advice. Cheers Chris Chris, what kind of TR6 is this ?. Is it a PI car or a US federal car converted from Strombergs to SU's etc ?. There are not that many tubes to work with but they vary from engine to engine and personally none are coming to mind for disconnecting to relieve run on other than inserting a valve in the servo hose to drop manifold vacuum and stall the engine. Connecting a tube (eg the AR valve to manifold on a federal engine) would make sense though. Stan Quote Link to post Share on other sites
chilly Posted January 6, 2009 Author Report Share Posted January 6, 2009 (edited) Hi Stan It is a CP UK car (1969) it did originally have fuel injection. I seem to recall it being something to do with vacuum Edited January 6, 2009 by chilly Quote Link to post Share on other sites
chilly Posted January 6, 2009 Author Report Share Posted January 6, 2009 This may help... Quote Link to post Share on other sites
chilly Posted January 6, 2009 Author Report Share Posted January 6, 2009 or this Quote Link to post Share on other sites
foster461 Posted January 6, 2009 Report Share Posted January 6, 2009 or this So I see crankcase ventilation, servo and fuel. Which would be disconnected to inhibit run on ? Stan Quote Link to post Share on other sites
chilly Posted January 7, 2009 Author Report Share Posted January 7, 2009 It can only be the breather that goes to the rocker box cover. What purpose does this serve? What might stop running-on ...blocking it off?, choking it down? or disconection from rocker box so it 'breaths' easier? Got to be one of these three options Quote Link to post Share on other sites
YankeeTR5 Posted January 7, 2009 Report Share Posted January 7, 2009 Tough call on that setup. I don't think based on the picture that unplugging any of the hoses will solve the problem - your setup looks pretty simple. The later (74 on?) US Spec TR6 had an anti-run on valve that effectively shut fuel off so the engine couldn't run on, but sourcing and setting that up on your car is pretty impractical. It was also part of a much more elaborate emissions set-up. On my first car - a TR3, I lived in a very hot climate (Central Valley in California) and in the summer run on was constant. The cheap, teenager fix was to turn the ignition off then press down on the gas pedal (I guess the fuel cooled things down enough that run on wouldn't happen). Later, a set of cooler spark plugs helped. Check the timing and make sure its not advanced - you could even retard the timing just a bit. Finally, running a lower temp thermastat couldn't hurt either. Best of luck....Dan Quote Link to post Share on other sites
67_gt6 Posted January 7, 2009 Report Share Posted January 7, 2009 (edited) I think the crankcase breather is a red herring as the hoses are connected in front of the throttles, so a hose leak is not going to weaken the mixture in the way that it would if the breather was connected to the inlet manifold. I think a photo of your distributor would be useful. I believe that carb TR6s had both vacuum retard and advance. andy Edited January 7, 2009 by 67_gt6 Quote Link to post Share on other sites
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