phil Dean Posted January 25 Report Share Posted January 25 I decided to take the TR out today for a bit of a run, Its not been on the roads for approx 3 months. However whilst garaged and I have been working on it I do start it up every 10 days or so. Even when really cold in the garage after a few turns it fires into life. I always let the car warm up before driving it adjusting the choke down by 2 settings then off. This morning was no different it drove down the road great after 2 miles I stopped turned of the engine to pick something up from a shop, started up again no problem drove for approx 1/2 mile and just as I was thinking of getting some more fuel, car had just under 1/4 of a tank in it.It I could a detect a flat spot between 2500 and 3000 revs, still stopped and got the fuel started back towards home the flat spot just became bigger 2500 to 3500 revs. Decided to take it on my test track the slip road up a roundabout from which you can get on to the motorway. By this time there was slight miss fire at approx 2500 revs that cleared at 3000 revs. but still felt flat up to 4000 revs. around the roundabout down the road to another roundabout towards home even on pick up from say 1500 revs it was missing slightly with the odd backfire thru the carbs. Back home Plugs out, all looked good with nice corn looking tips. Even fitted a spark checker on each lead restarted the engine and what to me looks like a great spark. Thought what have I done on the engine since I put it away 3 months ago , done loads on the rest of the car but on the engine only thing I had done was to wire in a cut off switch to the coil. Removed it back to wire direct to the coil and try again. Car started ok back out of the garage down onto the road but I could tell all was not well so decided to put it back in the garage, by this time it was backfiring and running lumpy as hell. got out the car it then cut out, restarted no problem but would only tick over for a minute before cutting out and sending a puff of greyish black smoke out off the Carb Filters, Started it again this time it took a few cranks before it would start up and then seam to be on 2 then 3 then 4 cylinders rev it . Its missing, then backfire thru the carbs then in the exhaust which caused plumes of black smoke out of the exhaust. Left it ticking over for about a minute then just it cut out. Since last year when I had the carbs rebuilt and the engine re tuned this engine has run brilliantly. Starts from cold and after choke adjustment it will usually sit there on tick over for ages without missing a beat. Not so at the moment. 1 thing which I am sure is not relevant but worth mentioning the starter motor has become lazy sometimes. Sometimes it will start the engine turning at normal speed other times it just about turns the engine over but enough for it to fire up. So is this an electrical fault or is it the dreaded water in fuel situation. or something more sinister , the black smoke on backfire out of the exhaust worries me. Any ideas gratefully received. Phil. Quote Link to post Share on other sites
stillp Posted January 25 Report Share Posted January 25 3 hours ago, phil Dean said: 1 thing which I am sure is not relevant but worth mentioning the starter motor has become lazy sometimes. Sometimes it will start the engine turning at normal speed other times it just about turns the engine over but enough for it to fire up. Phil, Are the battery earth strap and the block earth strap both making good connection to the body? Pete Quote Link to post Share on other sites
ctc77965o Posted January 25 Report Share Posted January 25 6 hours ago, phil Dean said: even on pick up from say 1500 revs it was missing slightly with the odd backfire thru the carbs. Sounds like weak mixture/fuel flow problem.... or just maybe a random failing ignition condensor. If it runs better if you pull the choke out then that points in the weak mixture direction...if you put a timing light on it and the timing is all-over-the-place then thats a condenser dying. Quote Link to post Share on other sites
keith1948 Posted January 25 Report Share Posted January 25 Try fresh fuel. A few years ago I filled up with bad fuel at a garage and the car was misfiring and running really badly. A friend had filled his car at same garage and had same issues. Problem disappeared after filling up at a different garage. I would eliminate fuel first before fiddling around with carbs etc. Also make sure battery is fully charged. See how it goes. Keith Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 25 Report Share Posted January 25 You didn’t top it up with diesel did you? Check your bill if you received one. No shame in it, I did it once and the car ran poorly until I drained and refuelled. Quote Link to post Share on other sites
Ralph Whitaker Posted January 26 Report Share Posted January 26 Sounds exactly like I had on the Dolomite last year after fitting an electronic module in the dizzy. One of the wires had rubbed through and was making intermittent earth with the body of the dizzy. I would check the wires in there and try a different condenser before doing anything else. Ralph Quote Link to post Share on other sites
roy53 Posted January 26 Report Share Posted January 26 (edited) sounds very similar to a problem i had last year. Chased electrical problems convinced it was that. It turned out to be a fuel blockage . Needle valve had blockage from a failing pump gasket glass bowl one. So check . i changed all electrics more than once. Re built carbs again Spent weeks solving this Roy should add i have solex/stromberg where the access is from underneath for thefloat bowl, much more difficult than SU Edited January 26 by roy53 add Quote Link to post Share on other sites
phil Dean Posted January 26 Author Report Share Posted January 26 (edited) Thanks for the answers 2 things, it started before I added the fuel, I always use shell or BP and from 2 busy petrol stations were they have at least one tanker a day. and no it wasn't diesel. The car is running Lumination electronic ignition. I wonder if that is breaking down. I think I will try a running thru a few things I have seen on the forum having done some research last night . If it will start run it with a bit of choke and pull the leads off one at a time see if that makes it worse. Maybe change the plugs. Then pump some fuel thru I have a secondary quality filter near the carbs I can check the fuel flow and see if theirs any water in it. I think on a mechanical pump you should fill a cup in approximately 7/8 seconds. Then check the carbs make sure there is enough oil in the pots then look for rubbish in the carbs. I have been working under the dash recently I just wondered if one of the wires on the ignition has come loose this happened to my mate in his TR6 last year took him weeks to find it. I am always reading info on the forum and even if Its something I am not doing at the time I cut and paste this into the TR4 folder on my computer. I have found notes on how to check the coil and the Lumination ignition system. so will add those to the list. Then after that its back to the drawing board. Phil. Edited January 26 by phil Dean Quote Link to post Share on other sites
Andy Moltu Posted January 26 Report Share Posted January 26 I had similar - her indoors said it smells of diesel. Receipt said otherwise, however when I contacted Tesco they asked “which pump” and admitted the super unleaded tank had been filled with diesel. Quote Link to post Share on other sites
phil Dean Posted January 27 Author Report Share Posted January 27 What happened after that Andy did they compensate you. Quote Link to post Share on other sites
Andy Moltu Posted January 27 Report Share Posted January 27 Yes. One I showed the receipt with the pump number. Did ok out of it. Drained the fuel a Nd took to recycling centre and filled with petrol and all was good. Quote Link to post Share on other sites
phil Dean Posted January 27 Author Report Share Posted January 27 Excellent. Started my car first time this morning no lumpiness, pulled the plug leads of one by one it ran rough every time I pulled a plug lead then fine when the lead was put back on. Decided to take it out for a drive expecting to be returning home any minute with a rough running car it ran great 3 times I took it out in a 30 mph zone pulling cleanly from 27mph up a slight hill in 4th to using my test track the motorway slip road it ran great, flat spot for 100 revs at 4000 revs but gets thru that and I don't usually rev it that hard. came home a brew a call from a mate who wanted a package picking up from a local shop whilst he is away Started the car went and got the package if there is any hesitancy its very slight at 1500 revs but the second third fourth time I tried it no problem. Now we all know the mechanical fairies have not been in my garage over night and we are never that lucky so further investigation. Watched the filter next to the carbs whilst it was ticking over and revving looks like a consistent flow of fuel. Check distributor it is not loose, took the dizzy cap of a small amount of burning on the rotar arm to the back of the arc came of once removed rotor from dizzy with wet and dry, a small amount of pitting on one of the pick up points in the cap cleaned it with my magic pen I use for cleaning old electrical connectors ,started it and drove it again. no problem. Theory and here I probably want shooting because I don't think I mentioned it in my original post, after cleaning the plugs yesterday I noticed the plunger on top of the carb had come loose and even popped out sat just in the top . Ah Ah I thought there is my problem screwed it back in but the car ran progressively worse until the massive misfire after which I turned it off and sent it to the naughty corner. Could it be and I am sure carb expects may put me right if I am wrong, that the plunger came loose during the drive and popped out, that would be when the misfire started am I right in thinking the plunger and oil keep the carb piston under pressure, during acceleration the piston opens up to let more air in when you back off its forced close by the plunger and oil in there. So maybe although I had screwed it back on yesterday without it resolving the problem the piston had jammed open and with lack of oil there wasn't enough pressure to push it back into its correct position therefore creating a very lean running engine, however overnight its slowly dropped down again and now under pressure the piston has worked correctly and the car has run fine today. !!! I wonder if I am going to be this lucky on this one. I have topped the oil up in the pots. Phil. Quote Link to post Share on other sites
Ralph Whitaker Posted January 28 Report Share Posted January 28 16 hours ago, phil Dean said: Excellent. Started my car first time this morning no lumpiness, pulled the plug leads of one by one it ran rough every time I pulled a plug lead then fine when the lead was put back on. Decided to take it out for a drive expecting to be returning home any minute with a rough running car it ran great 3 times I took it out in a 30 mph zone pulling cleanly from 27mph up a slight hill in 4th to using my test track the motorway slip road it ran great, flat spot for 100 revs at 4000 revs but gets thru that and I don't usually rev it that hard. came home a brew a call from a mate who wanted a package picking up from a local shop whilst he is away Started the car went and got the package if there is any hesitancy its very slight at 1500 revs but the second third fourth time I tried it no problem. Now we all know the mechanical fairies have not been in my garage over night and we are never that lucky so further investigation. Watched the filter next to the carbs whilst it was ticking over and revving looks like a consistent flow of fuel. Check distributor it is not loose, took the dizzy cap of a small amount of burning on the rotar arm to the back of the arc came of once removed rotor from dizzy with wet and dry, a small amount of pitting on one of the pick up points in the cap cleaned it with my magic pen I use for cleaning old electrical connectors ,started it and drove it again. no problem. Theory and here I probably want shooting because I don't think I mentioned it in my original post, after cleaning the plugs yesterday I noticed the plunger on top of the carb had come loose and even popped out sat just in the top . Ah Ah I thought there is my problem screwed it back in but the car ran progressively worse until the massive misfire after which I turned it off and sent it to the naughty corner. Could it be and I am sure carb expects may put me right if I am wrong, that the plunger came loose during the drive and popped out, that would be when the misfire started am I right in thinking the plunger and oil keep the carb piston under pressure, during acceleration the piston opens up to let more air in when you back off its forced close by the plunger and oil in there. So maybe although I had screwed it back on yesterday without it resolving the problem the piston had jammed open and with lack of oil there wasn't enough pressure to push it back into its correct position therefore creating a very lean running engine, however overnight its slowly dropped down again and now under pressure the piston has worked correctly and the car has run fine today. !!! I wonder if I am going to be this lucky on this one. I have topped the oil up in the pots. Phil. Phil, the damper, which is what the rod with the knurled top is, only slows the piston down on acceleration and deceleration as the vacuum changes in the carb. The downward pressure on the piston is applied by a long "slinky" spring. It could be that with the damper rod having become loose the piston at some point has moved upwards further than it would normally do and jammed up. After you put the damper back in and ran the car it may be that the heat of the engine warmed the carb up enough to release the jammed piston. Ralph Quote Link to post Share on other sites
keith1948 Posted January 28 Report Share Posted January 28 On Strombergs and I think same for SU's there is a piston lifting pin. Lift the piston and let it fall (with damper unscrewed). The piston should fall back with a slight clonk as it reaches the bottom of its travel. If it doesn't fall freely maybe it needs a clean. However the old adage if it aint broke don't fix it comes into play here. As the warm weather will come at some point then driving the car more will no doubt help. Suggest you leave things alone now it is working. Keith Quote Link to post Share on other sites
phil Dean Posted January 28 Author Report Share Posted January 28 Thanks Guys told you I didn't know what I was talking about, lets see how it reacts next time I use it, as you say if its not broke, but we will see. Phil. Quote Link to post Share on other sites
phil Dean Posted January 30 Author Report Share Posted January 30 Just had the car out for very short run cut short not because of a bad tempered car but major roadworks again have sprung up just down the road so didn't fancy trying to get a sick car back whilst queuing in traffic. It seams OK just very fluffy !! between 1500 and 1700 revs !! I am away on holiday as from Saturday for a week and straight down to the spares day at Stoneleigh when I get back but I think I will give it a run after then if its still a bit hesitant I will take the filters of the carbs and try the carb piston drop test whilst they are of just blow out all the fuel pipes up to the carbs. Any other suggestions gratefully received. Phil. Quote Link to post Share on other sites
roy53 Posted February 1 Report Share Posted February 1 Su or stromberg Quote Link to post Share on other sites
phil Dean Posted February 11 Author Report Share Posted February 11 Su but at the minute it really doesn’t matter the day before I was going Away I was out on my mountain bike the only 50 yards from my home I was just kissed almost just spoked by a car the resulting fall resulted in a week in hospital a dislocated elbow + 2 severe fractures and 2 cracks in my pelvis I now have a titanium joint in my elbow stainless steel pins and I think 2 shortened tr4 throttle cables to keep the tendons together. So it’s a long recovery and way back obviously it will be a long time before I can drive or even spanner the TR. Phil. Quote Link to post Share on other sites
RogerH Posted February 19 Report Share Posted February 19 Sounds like a disaster. Get well soon. Roger Quote Link to post Share on other sites
phil Dean Posted February 22 Author Report Share Posted February 22 Thanks Roger i am going to ask my mate who runs a TR6 to come up next week and start my car and take it up the road fora blast unfortunately because of my pelvis fracture he will have to go on his own I can’t get in the dam thing at the moment. So frustrating not only missing using the car but had to cancel so many motorsport things it’s race retro this weekend my favourite show already missed the trig parts day aaaaaah Phil. Quote Link to post Share on other sites
RogerH Posted February 22 Report Share Posted February 22 Concentrate on getting yourself sorted, the car will be there when you re-surface. Roger Quote Link to post Share on other sites
phil Dean Posted February 22 Author Report Share Posted February 22 Yep that’s what my wife and friends say and it’s true Quote Link to post Share on other sites
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