rhino_mac Posted September 19, 2014 Report Share Posted September 19, 2014 Ever since I've had my car, if you leave it for a day or so, it's a pain to start again. I've had a load of work done recently and she seems to be running sweetly enough (service, new points, new coil, new plugs/leads/rotor arm/dist cap etc, timing adjusted, new fuel lines, new choke cable and adjusted, new olives in the vacuum pipe etc etc). However, if you leave the car for any more than a day, it takes ages to start. If you manually prime the fuel pump with 4 or 5 pushes on the lever, it starts easily enough so we are assuming the fuel is either draining back, or evaporating from the float bowls. It's never not started but it's a massive drain on the battery cranking for a minute or more. The mechanic has said this is common for cars of this age and to save the battery I will need to lift the bonnet and prime the pump. This sounds fine, but to be honest, if I'm late for work on a sunny day, I'll be taking my day to day to save time which is a shame. Is this normal or should i be looking for another problem. Car starts fine within 12 hours so it's definitely a time related thing. ThanksRichard Quote Link to post Share on other sites
stuart Posted September 19, 2014 Report Share Posted September 19, 2014 The fuel pump needs a rebuild by the sound of it. Send it to David Davies 01942 891447 he is very good. Stuart. Quote Link to post Share on other sites
rhino_mac Posted September 19, 2014 Author Report Share Posted September 19, 2014 Hi Stuart, thanks for the reply. Forgot to mention the fuel pump is new, but it is a pattern part. Fitted in 2011 but car has only done about 200 miles since. Quote Link to post Share on other sites
RobH Posted September 19, 2014 Report Share Posted September 19, 2014 My car does exactly the same thing Richard - and it certainly isn't the fuel pump at fault. Neither can I see any leaks from the carb jets or the float chamber seals which is the obvious area to suspect. I've always assumed it to be evaporation via the overflow pipes, due to the increased volatility of modern petrol (benzene, propane, ethanol etc). I guess if you want to eliminate the hand-priming or cranking you could fit an electric fuel pump..... Rob Quote Link to post Share on other sites
Guest Posted September 19, 2014 Report Share Posted September 19, 2014 My money is on Stuart's suggestion. Given the fact that priming helps, it looks as if the pump struggles to get the fuel where it belongs. btw: do you prime before you start or after a few attempts? On the bright side: the starter motor helps building oil pressure, so when the engine starts, it has enough oil! Menno Quote Link to post Share on other sites
EdwinTiben Posted September 19, 2014 Report Share Posted September 19, 2014 Of course the problem should Be found and solved, But a Nice high torque starter helps to save battery as it has more power to run the engine Faster than the original. Quote Link to post Share on other sites
RogerH Posted September 19, 2014 Report Share Posted September 19, 2014 Hi Richard, inside the top of the fuel pump there are two non-return valves. They point in opposite directions. One opens to allow fuel from the tank and closes when the pump wants to push the fuel to the carbs. The other is closed when drawing fuel from the tank and then opens to let the fuel be pushed to the carbs. It could be that the NRV heading towards the carbs is leaking (it shouldn't). It is easy enough to remove the lid - you will need to blank off the tank pipe or attach an extended pipe above the tank level. The valve can be popped out by the use of a screwdriver into the outlet hole. Place to the lips and blow !! what happens - nothing should happen. No airflow. Either get a repair kit or send away as stated by Stuart. Roger Quote Link to post Share on other sites
rhino_mac Posted September 19, 2014 Author Report Share Posted September 19, 2014 High torque starter fitted too. It spins fine, just takes ages to catch. The car had no overflows on the float bowls (safe huh) so these have just been replaced. I never tried priming the pump before. We were talking in the garage and tried to start it and it just turned over for 5 to 10 seconds. That's when the mechanic primed the pump and it started straight up with no throttle. He thinks it's evaporation. I just wondered if it was common or if I should be looking for something else. Quote Link to post Share on other sites
RobH Posted September 19, 2014 Report Share Posted September 19, 2014 Richard - I think you can ignore all the speculation about the fuel pump (sorry guys). As I said above I had this problem with both an old and new fuel pump so it certainly isn't that. There is no way the NRV. could be responsible because the float valve stops that. The function of the NRV is to allow the pump to work by sucking fuel from the tank rather than the carb and if the car is driving OK there is nothing wrong with it. This is purely down to loss of fuel from the float chamber with the engine off which I believe is evaporation or leakage. I can smell it in the garage - I just have not narrowed down where it comes from. As for the excessive cranking- perhaps people don't understand how the fuel pump works. It isn't the cam which does the pumping - its the return spring. All the cam does is lift the diaphragm so the spring can pump (it has to be that way to prevent excessive fuel line pressure). The system is designed to provide enough fuel at full chat - not to quickly fill an empty float chamber at cranking speed - hence it takes a lot of cranking to do that. If there was a fuel pump problem it would be evident as a loss of power. Rob Quote Link to post Share on other sites
rhino_mac Posted September 19, 2014 Author Report Share Posted September 19, 2014 Hi Rob, I can definitely smell something in the garage.....................to be honest I thought that was what all classic cars smelled like It's not a big problem, particularly if it's "one of those things they all do" but if it's not right, then I'd like to find a cure. Quote Link to post Share on other sites
BillS Posted September 19, 2014 Report Share Posted September 19, 2014 I too had the problem re starting after a day or so of inactivity - in my case petrol was slowly seeping from the carbs where float chambers bolt onto carb body. Rebuild kit for carbs have appeared to sort it. Quote Link to post Share on other sites
RogerH Posted September 20, 2014 Report Share Posted September 20, 2014 Hi Rob, that sounds very logical. I've had problems with my NRV's hence my jumping at that. Roger Quote Link to post Share on other sites
RobH Posted September 20, 2014 Report Share Posted September 20, 2014 It sounds as though Bill is probably on the right track here. Looking at the diagrams there are two hat-shaped rubber washers each side of the float-bowl bottom fixing bolt on the H6 carb, and that is also the feed route for fuel. I've got some H6 gasket kits somewhere so I'll dig them out and see of its a cure. Rob Quote Link to post Share on other sites
Richardtr3a Posted September 24, 2014 Report Share Posted September 24, 2014 I fitted these new top hat washers and still had a leak. In the end a mobile tuner fitted a spare copper washer under the bolt that passes through the rubber washers and this made a little more pressure and the problem was over. I understand that when these cars were sent new to some parts of Africa, they had a problem with these washers because of the petrol quality. Standard Triumph's answer was to include an extra set of rubber washers with the new cars ! How about fixing the problem ? Quote Link to post Share on other sites
BlueTR3A-5EKT Posted September 24, 2014 Report Share Posted September 24, 2014 (edited) Simple question - does your choke pull the jets down fully? I had this issue and it was that the choke cable needed another 1/2" pull once the resistance of the throttle advance cam was encountered. Get the choke pulled right out as you usually do when trying to start, then check to see if the brass levers that work the jets will pull the jets down any further. Cheers Peter W Edited September 24, 2014 by BlueTR3A-5EKT Quote Link to post Share on other sites
jocklow Posted September 30, 2014 Report Share Posted September 30, 2014 I had the problem with knobs on. Tried all the previously suggested. They are all good points. In my case I moved on to checking compression. Despite the engine's small mileage since someone previously had rebuilt it ,the compression was down on two cylinders. I ended up taking it out and rebuilding it completely, but I think the biggest effect in my case was new valves and valve seats. It starts fine now. I had a TR2 50 years ago and it started living outside in winter in Birmingham with batteries that weren't brilliant. Quote Link to post Share on other sites
rhino_mac Posted September 30, 2014 Author Report Share Posted September 30, 2014 My bottom end is being rebuilt as I type this. Part of the engine checks were compression tests so I'll be interested to see the results in a few days when I pick it up. My understanding is that if all is OK they should start first click of the starter. If compression is OK, I think the carb seals are the first place to look as it seems to be an evaporation issue. Quote Link to post Share on other sites
MikeF Posted September 30, 2014 Report Share Posted September 30, 2014 I had this problem creep up on me on my 4 and went for the fuel pump as it seemed the obvious thing, but there was nothing wrong with it (by the blow down the pipes method above). Then I got to more logical thinking and long story short it was the carbs. Essentially out of adjustment choke/choke cable and sticking float chamber in No.1 carb. So now its all OK.FWIW for a perspective: on my car the float chambers do deplete after about 10 days, and it takes about two 5 second bursts on the starter to prime them back. Otherwise it starts immediately - well a second or two. MikeMike Quote Link to post Share on other sites
MRG1965 Posted October 1, 2014 Report Share Posted October 1, 2014 Hi, mine is the same as Mikes. If I leave it for a week or so between drives( don't judge me) the fuel evaperates from the float chambers. I finally worked what the problem was as I also had cranking speed issues, but that was resolved with earth straps. Then I decided to pop the bonnet one day to see if i was right and manually operate the pump and could hear distinintly the sound of fuel rushing in to the float chambers and then lock up as the floats closed the valves. Then started first piston up. Anybody have a solution to this? Mark Quote Link to post Share on other sites
Fireman049 Posted October 1, 2014 Report Share Posted October 1, 2014 (edited) My solution was to fit an SU electric petrol pump to my 3A. I've always been an advocate of electric pumps. Whenever I switch the ignition on I hear the pump clicking away filling the float chambers and the TR starts immediately. If anyone would like photo's of my set-up then please PM me your eMail address. Tom. Edited October 1, 2014 by Fireman049 Quote Link to post Share on other sites
Geko Posted October 1, 2014 Report Share Posted October 1, 2014 Plus some perks: if you run out of fuel because the gauge-sender-is-not-reliable you can hear the pump gasping for fuel:"prrrrrrr..."; you can add an anti-theft switch; you can add venting pipe for better crankcase ventilation on the fuel pump blanking plate for TR4A. Mine is a Mitsubishi from the junkyard and has served me without fail for the past 9 years Quote Link to post Share on other sites
MRG1965 Posted October 1, 2014 Report Share Posted October 1, 2014 Yes I used to have an Austin 1100 where the pump did that on low fuel on right hand corners. Don't recall the similar 1300 GT i had doing the same, but 35 years tends to confuse some memories. like the idea of the electric fuel pump as I was going to fit a fuel shut off solonoid as part of security measure so that might be a better solution as I also have a tracker that shuts off a couple systems via solenoids and a mobile phone. Do like the original look of fuel pump and filter bowl, have a spare so may remove the lever and some internals to keep the original look as the fuel will push through with an electric pump near the tank and also to perplex any would be thief a little. Mark Quote Link to post Share on other sites
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