DRIVING - me bonkers.
Discussion
My Bayliss Thomas is being a right pain in the bottom, you may recall the carb' has been restored by Burlens and this certainly got the old girl running well. BUT - it keeps conking out sometimes after 10 mile run and sometimes after 1 mile or less. I have checked and cleaned the filter in the fuel tap, fuel is running freely into carb' bowl. I have checked the main jet is clear, I have checked the petrol cap breather is clear, I have tried all sorts of float hights using the washers Burlens supplied from flooding to nothing. Getting the best balance between the two the engine runs in the driveway at fairly high revs with no problem and yet take it on the road and within a mile it conks out!! I then tickle the carb' and the engine starts up (some reluctance)and will run cleanly for another mile, repeat process. The other day it ran fine for 15 miles until it conked and repeat process as above. I am sure it must be petrol starvation but am at a complete loss as to how I can resolve this strange problem. Tomorrow it may run for ten miles no problem or it may only do a mile?? Perplexed and mystified I think I may have to have the expert garage to have a look. Any thoughts please.
is it worth going for a run with your fuel cap off, just to eliminate it from the list of suspects?
get a powerful torch and see if you can see anything blocking the outlet from the fuel tank, sometimes they have a gauze mesh over the outlet, if this is getting blocked up with rust flakes it could restrict fuel flow.
check all fuel lines for kinks, and if you have any flexi pipes take them off and see if they've started to collapse inside (they may still look fine on the outside).
if there is a fuel tap below the tank it might be worth seeing if its not been blocked by a bit of rust or something similar.
get a powerful torch and see if you can see anything blocking the outlet from the fuel tank, sometimes they have a gauze mesh over the outlet, if this is getting blocked up with rust flakes it could restrict fuel flow.
check all fuel lines for kinks, and if you have any flexi pipes take them off and see if they've started to collapse inside (they may still look fine on the outside).
if there is a fuel tap below the tank it might be worth seeing if its not been blocked by a bit of rust or something similar.
Thanks for suggestions, I have double checked that the breather hole in fuel cap is clear, it is but I will give it a run with cap off to be 100% sure this is not the problem. I have checked and removed the wire filter from the fuel tap, all clear and fuel runs out of carb' end OK so no blocks there, The fuel pipe is copper right thry except the 3 inches of new flexible fuel pipe I fitted a few weeks back.
A thought came to me, could it be the coil or something like that sort of breaking down do you think?? a sort of intermittent failure.
Further thinking back, the engine runs for longer from cold, when its hot it seems to start the trouble off. Could it be possible that by the time I have spluttered to a halt, got out and tickled the carb and got back to start the electrical item has cooled just enough to run for a while (I'm desperate).
A thought came to me, could it be the coil or something like that sort of breaking down do you think?? a sort of intermittent failure.
Further thinking back, the engine runs for longer from cold, when its hot it seems to start the trouble off. Could it be possible that by the time I have spluttered to a halt, got out and tickled the carb and got back to start the electrical item has cooled just enough to run for a while (I'm desperate).
Edited by crankedup on Sunday 18th March 14:45
The coil is a possibility too, so if it conks out check the plug spark by taking a spare plug with you and resting it against the block with the plug cap attached and then crank the engine with the ignition on. You'll soon see if there is a spark. Of course you could just hold the plug and even with your eyes closed you'll soon know if there is HT current - lol. It can't be points since that would be a terminal failure and actually is worse when the engine is cold than hot if the points have closed up. I still favour a fuel blockage though since you started out by saying it sometimes happened after one mile and others 10 miles. Oh, take a spare coil with you too just in case!
Had this happen to me once on a car, checked absolutely everything without success. In the end I removed the fuel filter from the sender in the tank and it ran perfectly after that. I will add that the filter looked clean enough, but I lobbed it in desperation.
Give it a go - it's worth a try.
Give it a go - it's worth a try.
crankedup said:
Thanks for suggestions, I have double checked that the breather hole in fuel cap is clear, it is but I will give it a run with cap off to be 100% sure this is not the problem. I have checked and removed the wire filter from the fuel tap, all clear and fuel runs out of carb' end OK so no blocks there, The fuel pipe is copper right thry except the 3 inches of new flexible fuel pipe I fitted a few weeks back.
A thought came to me, could it be the coil or something like that sort of breaking down do you think?? a sort of intermittent failure.
Further thinking back, the engine runs for longer from cold, when its hot it seems to start the trouble off. Could it be possible that by the time I have spluttered to a halt, got out and tickled the carb and got back to start the electrical item has cooled just enough to run for a while (I'm desperate).
A thought came to me, could it be the coil or something like that sort of breaking down do you think?? a sort of intermittent failure.
Further thinking back, the engine runs for longer from cold, when its hot it seems to start the trouble off. Could it be possible that by the time I have spluttered to a halt, got out and tickled the carb and got back to start the electrical item has cooled just enough to run for a while (I'm desperate).
Edited by crankedup on Sunday 18th March 14:45
going along with the dodgy electrics, could it be the condensor? they are known to break down and give intermitant running as well.
Yes it is possible that the condensor is tired as well, most likely best bet is to renew coil and condensor I guess. Looked at the fuel filter suggestion Squadron Leader, the only filter was at base of fuel tap and I had removed that. Electrics are becoming a bigger suspect than fuel problem to me now, really thinking about how reluctant the engine is to start from warm.
I shall post up the answer when I've got it sorted, meanwhile thanks for all the suggestions.
I expect as sonn as the old girl runs like a goodun some other vintage lovely will take my eye.
I shall post up the answer when I've got it sorted, meanwhile thanks for all the suggestions.
I expect as sonn as the old girl runs like a goodun some other vintage lovely will take my eye.
incorrigible said:
Haven't read all the replies, sorry
Is the coil meant to have a ballast resistor fitted? and is it fitted? Too much juice going to the coil can have a similar effect (you may need additional wiring to bypass the resistor on start up)
Is the coil meant to have a ballast resistor fitted? and is it fitted? Too much juice going to the coil can have a similar effect (you may need additional wiring to bypass the resistor on start up)
No I don't think it is meant to have a ballast resistor, its only running on 6V coverted to coil ignition in 1997. Have to say I reckon the coil provided back in 1997 when the conversion was done must have been a second hand unit, it looks all of 40 years old. Its covered in rust and has a brown bakelite (like) material at the end where the electrics screw onto. The design is very very old.
I've had enough of it now and booked it in for the laying on of expert hands. So frustrating.Nick_F said:
Fuel vapourisation? Should your nice new carb be better insulated from the head?
Its a good point but all the vintage cars were pretty well the same so far as the carb'/relation to engine are concerned. Its the same as my vintage Austin and that runs fine. But thanks for the suggestion.
If the garage find a technical fault with the carb' it may have to go back to Burlens for a re-check. On the other hand it might be the condensor gone caput, and thats hidden in the depths of the magneto
As this seems to be dragging on a bit I've given it a second thought since the root of the problem can only be either sparks or fuel. A question I should have asked before is whether the cut out, when it happens , is sudden, from power to no power (electrical failure) or gradual with the usual coughing and spluttering as the engine dies on you (fuel starvation)
If the former then the usual culprit, as mentioned above, is the coil getting hot (but in this weather?), failing which the distributor, but the symptoms seem to rule out the distributor or points. There is a faintest possibility that this could be down to tracking in the distributor cap but that is so unlikely as to be almost ruled out. HT leads? Not all at once giving out. Hmmm
If the second type of loss of power of course we look to fuel starvation. You say the pipes are all copper except for one small piece so there should be no question of a pipe collapsing and causing the starvation. I've known this a few times with flexis. Could it be a partial blockage in the copper pipes? The way to find out is to get a 5 litre can and jury rig it to the carburettor flexi so if the car runs well the fuel lines need investigating.
I'd love to hear from you more and hope that this infuriating problem can be resolved. You've not mentioned whether the car starts easily again after the breakdown and if so how long does it take? Will she fire up readily after say 10 mins or do you have to churn her over? Oh, and just a silly question here. The battery terminal are well screwed on?
If the former then the usual culprit, as mentioned above, is the coil getting hot (but in this weather?), failing which the distributor, but the symptoms seem to rule out the distributor or points. There is a faintest possibility that this could be down to tracking in the distributor cap but that is so unlikely as to be almost ruled out. HT leads? Not all at once giving out. Hmmm
If the second type of loss of power of course we look to fuel starvation. You say the pipes are all copper except for one small piece so there should be no question of a pipe collapsing and causing the starvation. I've known this a few times with flexis. Could it be a partial blockage in the copper pipes? The way to find out is to get a 5 litre can and jury rig it to the carburettor flexi so if the car runs well the fuel lines need investigating.
I'd love to hear from you more and hope that this infuriating problem can be resolved. You've not mentioned whether the car starts easily again after the breakdown and if so how long does it take? Will she fire up readily after say 10 mins or do you have to churn her over? Oh, and just a silly question here. The battery terminal are well screwed on?
lowdrag said:
As this seems to be dragging on a bit I've given it a second thought since the root of the problem can only be either sparks or fuel. A question I should have asked before is whether the cut out, when it happens , is sudden, from power to no power (electrical failure) or gradual with the usual coughing and spluttering as the engine dies on you (fuel starvation)
If the former then the usual culprit, as mentioned above, is the coil getting hot (but in this weather?), failing which the distributor, but the symptoms seem to rule out the distributor or points. There is a faintest possibility that this could be down to tracking in the distributor cap but that is so unlikely as to be almost ruled out. HT leads? Not all at once giving out. Hmmm
If the second type of loss of power of course we look to fuel starvation. You say the pipes are all copper except for one small piece so there should be no question of a pipe collapsing and causing the starvation. I've known this a few times with flexis. Could it be a partial blockage in the copper pipes? The way to find out is to get a 5 litre can and jury rig it to the carburettor flexi so if the car runs well the fuel lines need investigating.
I'd love to hear from you more and hope that this infuriating problem can be resolved. You've not mentioned whether the car starts easily again after the breakdown and if so how long does it take? Will she fire up readily after say 10 mins or do you have to churn her over? Oh, and just a silly question here. The battery terminal are well screwed on?
If the former then the usual culprit, as mentioned above, is the coil getting hot (but in this weather?), failing which the distributor, but the symptoms seem to rule out the distributor or points. There is a faintest possibility that this could be down to tracking in the distributor cap but that is so unlikely as to be almost ruled out. HT leads? Not all at once giving out. Hmmm
If the second type of loss of power of course we look to fuel starvation. You say the pipes are all copper except for one small piece so there should be no question of a pipe collapsing and causing the starvation. I've known this a few times with flexis. Could it be a partial blockage in the copper pipes? The way to find out is to get a 5 litre can and jury rig it to the carburettor flexi so if the car runs well the fuel lines need investigating.
I'd love to hear from you more and hope that this infuriating problem can be resolved. You've not mentioned whether the car starts easily again after the breakdown and if so how long does it take? Will she fire up readily after say 10 mins or do you have to churn her over? Oh, and just a silly question here. The battery terminal are well screwed on?
Hi Lowdrag, The car (1925 Bayliss Thomas) is new to me, it did'nt run properly when I bought it but thought it fudementally sound. It has'nt really been used for the last ten years (wonder why)but like lots of vintage cars thats not really odd.
She starts from cold fairly easy, certainly when compared to a hot start when I have to keep the starter churning over for for perhaps 5 - 7 seconds or so, and then it may need a second churning before firing into life. She will run from cold in the drive no problem, altho I have only let it run 5 minutes as the car is thermo syphon cooling with no rad fan. I now run down the road and it conks out after half to one mile, tickle carb' and she starts reluctantly to repeat process. The problem has definetly become more acute over the past few weeks to the point where a drive is out of the question.
When she conks out it is certainly a spluttering coughing backfiring scenario indicative of fuel starvation and this has been the consistant scenario. I have now replaced the ignition coil with a brand new one to no avail.
The car has been converted to coil ignition(6V) thru the existing mag/contact points which I guess means that it is running with the old condensor hidden in the depths of the mag'. I'm wondering if it could be that thtas causing the problem as well now, or maybe I'm getting paranoid! It looks like new plug leads have been put on, certainly they look fresh and clean. I'm not sure about the H.T. lead tho, that could be old and I think is worth changing.
It may be a partial blockage in the old copper fuel pipe, as you suggest, and I think I will have this cleaned out.
Thank you for your interest Lowdrag, it is certainly the worst perplexing mechanical problem I have come up against. I have now booked the car into my local engineering garage for the laying on of expert hands and use of pro' equipment to trace the fault(s) and I will be posting up the results in a couple of weeks time. I know that the car is a good'un with a lovely strong engine and I'm looking forward to enjoying a Summer of driving, altho my confidence in it has taken rather a battering.
We now are - as near as dammit - certain that this is fuel starvation. I don't know the type of car but does it have a fuel pump or is it gravity feed? The car, even if it has a pump, is too old to have a recirculation system so there must somewhere, with or without a pump, be a blockage. The fact that tickling the carb makes her, albeit reluctantly, fire up is symptomatic of that. The enforced halt has given the fuel time to slowly filter through to the carb. However, if there is a pump is it mechanical or electrical? Could the pump be cavitating? This used to be a big problem with early E types with the immersed pump - the bakolite impeller broke and the pump just whizzed round doing nothing.
Please don't think that I am trying to make life more complicated, I am racking my brains as to what is causing the actual problem. However, since the car had been standing for years, I assume you emptied the tank and threw away the old juice and cleaned the system through before firing her up. I bought a Mk 1 Jaguar some time back that had been standing for 8 years and the fuel was well and truly off. If you didn't fill with fresh fuel and let it run through the fuel lines before reconnecting to the carb you are almost certain to have a load of sh.. - er - detritus in there.
Please don't think that I am trying to make life more complicated, I am racking my brains as to what is causing the actual problem. However, since the car had been standing for years, I assume you emptied the tank and threw away the old juice and cleaned the system through before firing her up. I bought a Mk 1 Jaguar some time back that had been standing for 8 years and the fuel was well and truly off. If you didn't fill with fresh fuel and let it run through the fuel lines before reconnecting to the carb you are almost certain to have a load of sh.. - er - detritus in there.
lowdrag said:
We now are - as near as dammit - certain that this is fuel starvation. I don't know the type of car but does it have a fuel pump or is it gravity feed? The car, even if it has a pump, is too old to have a recirculation system so there must somewhere, with or without a pump, be a blockage. The fact that tickling the carb makes her, albeit reluctantly, fire up is symptomatic of that. The enforced halt has given the fuel time to slowly filter through to the carb. However, if there is a pump is it mechanical or electrical? Could the pump be cavitating? This used to be a big problem with early E types with the immersed pump - the bakolite impeller broke and the pump just whizzed round doing nothing.
Please don't think that I am trying to make life more complicated, I am racking my brains as to what is causing the actual problem. However, since the car had been standing for years, I assume you emptied the tank and threw away the old juice and cleaned the system through before firing her up. I bought a Mk 1 Jaguar some time back that had been standing for 8 years and the fuel was well and truly off. If you didn't fill with fresh fuel and let it run through the fuel lines before reconnecting to the carb you are almost certain to have a load of sh.. - er - detritus in there.
Please don't think that I am trying to make life more complicated, I am racking my brains as to what is causing the actual problem. However, since the car had been standing for years, I assume you emptied the tank and threw away the old juice and cleaned the system through before firing her up. I bought a Mk 1 Jaguar some time back that had been standing for 8 years and the fuel was well and truly off. If you didn't fill with fresh fuel and let it run through the fuel lines before reconnecting to the carb you are almost certain to have a load of sh.. - er - detritus in there.
I certainly don't think your trying to make life difficult, far from it I am grateful for your efforts in assisting me. The car is a 1925 Bayliss Thomas, an English built car running its original engine and gearbox, in fact mostly all original. It has the Meadows 4 cylinder engine with OHV and thermo syphon cooling. The mechanics are excellent (save the current problem)I have seen 49mph on the speedo which for the class of car is excellant going! On that day it ran sweetly for about 10 miles.
It has'nt got a fuel pump, it is and always has been gravity feed. The previous owner told me that he only tried to use the car once and on that occasion the flexible drive couplings on the prop' shaft disintegrated from old age. These he replaced prior to sale to me. He told me that the owner prior to him simply stood it in a dry barn for years!
The petrol in the tank was put in by previous owner, he only owned the car for 3 months, so I assumed that the petro; was reasonbly fresh. I have managed to use several tanks since, it only holds 4 gallons. When the carb' came back from Burlens I had run some petrol thru the feed line and it did seem a little slow. Perhaps this is the problem as you suggest it could be a partial blockage in the copper fuel pipe. I will ask the garage if they are able to blow compressed air thru and if this may clear any muck. Otherwise its a new one, I expect they will have a look at the carb' to ensure its OK.
When the old girl is finally running nicely I am going to treat her to a re-paint, I am currently learning the art of coach painting with a brush on my Austin mudguards. The poor old Bayliss has at some time been subjected to an vile coat of what I can only describe as 'Council Green'. Totally unsuited to the car and out of period, being its one of only ten survivors I think it deserves better!
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