KOB Posted September 2, 2019 Report Share Posted September 2, 2019 I have been running twin 175 Strombergs on my 6 for around 22 years, these are fed by a Facet pump in the boot. The pump had become problematic earlier this year so I replaced it with a new Facet pump. I now have bypass issues at the carb needle valve. I understand the facet generates up to 5psi and this may be a little high for Stromberg carbs, does anyone have a fuel line pressure regulator fitted for this set up ? Quote Link to post Share on other sites
JochemsTR Posted September 2, 2019 Report Share Posted September 2, 2019 Strombergs no more than 3 PSI! Measure at Floater level. Pressure Regulator required. Jochem Quote Link to post Share on other sites
AarhusTr6 Posted September 2, 2019 Report Share Posted September 2, 2019 Hi Kob I did not know you could do this, ie put an electronic pump onto some Stromburgs. Is this a common practice? Rich Quote Link to post Share on other sites
barkerwilliams Posted September 2, 2019 Report Share Posted September 2, 2019 Rich, Triumph Stag 2 x CD175's. Electric pump, now electronic, does not run continuously with a bypass but runs as needed to maintain pressure. Yes as posted above 3psi is enough for the Stag. Alan Quote Link to post Share on other sites
Andy Moltu Posted September 2, 2019 Report Share Posted September 2, 2019 The Stag has a little pump in the boot which gives a gentle thumping noise when you first switch the ignition on (prior to starting) which reduces in frequency as the pressure builds up. Presumably a Stag pump could be used on a TR as I think the pressure requirements are similar for the twin Strombergs of the Stag. Quote Link to post Share on other sites
Waldi Posted September 2, 2019 Report Share Posted September 2, 2019 I would avoid a pressure regulator on a carburetted engine, it is adding complexity and probably a continuous overflow back to the tank. I would buy a proper pump instead. Waldi Quote Link to post Share on other sites
JochemsTR Posted September 2, 2019 Report Share Posted September 2, 2019 1 hour ago, Waldi said: I would avoid a pressure regulator on a carburetted engine, it is adding complexity and probably a continuous overflow back to the tank. I would buy a proper pump instead. Is really no problem. Before my EFI I had 2 ZS Strombergs with FilterKing regulator and Pierburg electrical pump. Works perfect. Jochem Quote Link to post Share on other sites
harlequin Posted September 2, 2019 Report Share Posted September 2, 2019 Hi I have CD175s on my 6 supplied by a Facet pump (I think the pump is intended for a boat) mounted under the bonnet, I had a Sytec regulator fitted which gave problems from day one so changed to a Malpassi regulator, this has been absolutely trouble free for the last five years. Prior to fitting the Facet pump I had the standard mechanical pump which occasionally caused some overflowing issues. My TR3 has SUs and the standard pump and this also occasionally overflows, I have replaced the float chamber needle valves but still it will flood now and then especially if the car has not been used for about a week George Quote Link to post Share on other sites
pheaney Posted September 5, 2019 Report Share Posted September 5, 2019 Hi I use a facet silver top pump (480530K) for my Strombergs . It comes rated at 5-6 psi but I replaced the internal spring with a 3 psi replacement to be sure. https://www.ebay.co.uk/itm/230984130252 Regards Paul. Quote Link to post Share on other sites
dingle Posted September 5, 2019 Report Share Posted September 5, 2019 Actually, 3 psi is a bit high. My Hayne's manual specifies 1.5-2.5 psi. Berry Quote Link to post Share on other sites
KOB Posted September 6, 2019 Author Report Share Posted September 6, 2019 11 hours ago, pheaney said: Hi I use a facet silver top pump (480530K) for my Strombergs . It comes rated at 5-6 psi but I replaced the internal spring with a 3 psi replacement to be sure. https://www.ebay.co.uk/itm/230984130252 Regards Paul. thanks Paul, that is really helpful, I had no idea springs were available Quote Link to post Share on other sites
Waldi Posted September 6, 2019 Report Share Posted September 6, 2019 3psi will still give a head (height of fuel column above the pump) of around 2.5 m. That should be more than enough. If a lower rated spring like 3 psi or less is available I would try that first. There is often some margin in the design, so 3 psi might stop the flooding. Waldi Quote Link to post Share on other sites
dingle Posted September 6, 2019 Report Share Posted September 6, 2019 Just a thought about fuel pumps. In the 50+years that I have been puttering with TRs, the stock mechanical pump has never been a source of trouble, unlike electric ones. The original AC brand pumps can be rebuilt with kits available and are bullet proof. Stay away from the low cost non-rebuildable pumps. Berry Quote Link to post Share on other sites
foster461 Posted September 8, 2019 Report Share Posted September 8, 2019 The only problem with the mechanical pump is that if the car is not used regularly it can take a lot of cranking to fill the carbs again. The electric pumps are inexpensive and small so once you have done the conversion it is easy and quick to swap the pump with a spare that you always have with you. I dont see a problem with using a regulator but there are suitable pumps off the shelf that operate at the correct 1.5 to 2 psi. Stan Quote Link to post Share on other sites
Robin Powell Posted September 8, 2019 Report Share Posted September 8, 2019 Why not use a Huco pump designed for the job giving 2.1psi. https://www.dellorto.co.uk/shop/car-accessories/fuel-pumps-regulators-accessories/huco-low-pressure-12v-fuel-pump-133010/ I have used one in my TR4A on SUs for a number of years with no problem. Quote Link to post Share on other sites
RobH Posted September 8, 2019 Report Share Posted September 8, 2019 57 minutes ago, foster461 said: The only problem with the mechanical pump is that if the car is not used regularly it can take a lot of cranking to fill the carbs again. Which maybe could be argued as a good thing because it allows oil pressure to build up before the engine fires. (Unless you crank it first with the plugs out of course). Quote Link to post Share on other sites
dingle Posted September 8, 2019 Report Share Posted September 8, 2019 3 hours ago, foster461 said: The only problem with the mechanical pump is that if the car is not used regularly it can take a lot of cranking to fill the carbs again. The priming lever on the original pumps must have been designed with that issue in mind. Berry Quote Link to post Share on other sites
harlequin Posted September 9, 2019 Report Share Posted September 9, 2019 (edited) I'm a fan of electrical pumps! Instant start up and vapour lock is a thing of the past, it also came in handy when a friend ran out of fuel, we disconnected the fuel line from my carb and pumped fuel into a bottle to tip into the empty cars tank. One of our group had a scare with his mechanical pump, he had left the back of the car on ramps while he was away from home for a few days, when he got home the house stank of petrol. He went into the integral garage and found that the fuel tank had drained through a faulty pump into the sump then when that was full it found its way out onto the garage flour. Luckily it was Summer and the boiler had not fired up and caused a big bang. George Edited September 9, 2019 by harlequin Quote Link to post Share on other sites
stillreel Posted September 9, 2019 Report Share Posted September 9, 2019 I have a similar issue; the 73 TR6 starts and runs really well but after stopping (when the engine is hot) the idea goes all to hell, almost stalling out on the re-start. Any suggestions??? BC Quote Link to post Share on other sites
dingle Posted September 9, 2019 Report Share Posted September 9, 2019 Not to over beat the drum for mechanical pumps, but it is also possible for the fuel to make its way into the crankcase through a float valve that is stuck open. With either type of pump, it is cheap insurance to install a shut off valve and close it before long term storage. Berry 4 hours ago, harlequin said: One of our group had a scare with his mechanical pump, he had left the back of the car on ramps while he was away from home for a few days, when he got home the house stank of petrol. He went into the integral garage and found that the fuel tank had drained through a faulty pump into the sump then when that was full it found its way out onto the garage flour. Luckily it was Summer and the boiler had not fired up and caused a big bang. Quote Link to post Share on other sites
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