Overhauled carb/new petrol pump relationship issues!

[raygeorge]

We have a Triumph 1200, Solex Carb which was completely refurbed by Carburettor Exchange (beautiful job) and we then fitted a new petr

ol pump from David Manners which is just overwhelming it. There are human analogies! We know why the pump is  doing it, but can anyone help with a remedy, short of divorce. e.g. does anyone know where an original pump could be sourced, or an overhauled original to original spec.

A Very Happy Easter 

 

Ray

[johny]

In some cases new pumps have to have extra packers installed where the mount on the block so that their operating arm is moved away from the cam. This results in less pump pressure but to get the correct thickness of packer you really need to measure the fuel pressure...

[Josef]

There’s a few threads on this. Either replacing the spring on the lever in the pump with an original one, or spacing the pump further from the engine are the recommended solutions if I remember correctly. 

[Pete Lewis]

many of the aftermarket copy pumps are well know to produce 6 to 10 psi  far more than the float needle valve  can cope with 

we fitted a rimmers pump to a local troubled spitty  and it blew fuel from everywhere    just hopeless 

Josef has summed it up  use an old pump spring or add packing to space the pump lever way from the block has worked to solve this rubbish parts syndrome 

you dont need more than 2.5 psi to work correctly 

there are low pressure hucco electric pumps used by many they are rated as 2.5psi 

Pete

[raygeorge]

Thanks to you all for replying. Sooo...next question - how to achieve the spacing. Is there are thicker gasket available..... idiot's guide to the solution please!

Ray

[Pete Lewis]

cornflake packets used to work  

there are plastic spacers not always easy to find 

the 1500 had along arm pump and a plastic insulating spacer  but thats probably too thick 

then there can be the studs become too short    all a bit of a  faf when the manufacturer should stick to a basic  specification ...

not searched on here but seem to remember about 3mm was used to drop the output 

Pete

[johny]

Yes or buy more gaskets from the usual suspects?

[raygeorge]

could you identify favourite usual suspects for additional gaskets or extra thick ones (gasket not owner!)

Ray

[johny]

jamespaddock.co.uk have standard gaskets at 20p each. Then theres VAT and postage so best bought as part of a larger order...

[raygeorge]

Thank you all!  Can anyone advise how much packing in mm might work to alleviate the problem. I am going to go back to Manners also to see what they say - seems bonkers selling petrol pumps for heralds when they are bound to behave in this way.....

Ray

[johny]

The original workshop manual stated that replacement pumps may need this adjustment to get the pressure right. This is because pumps are made by third parties plus their springs may well weaken over time so the initial pressure they deliver is a bit of an unknown....

[Pete Lewis]

its a common problem as sold by so many     these days     just copies not built to a specification 

pete

[daverclasper]

I seem to remember, packing out between 3-5mm? from an old thread? 

[Stratton Jimmer]

20 hours ago, daverclasper said:

I seem to remember, packing out between 3-5mm? from an old thread? 

From a post dated 16 Feb 2022.

Posted February 17, 2022 by me in answer to the question "How thick were the gaskets?"

  Only about 3mm. Self cut gaskets from sheet.

[Josef]

On 09/04/2023 at 19:00, raygeorge said:

could you identify favourite usual suspects for additional gaskets or extra thick ones (gasket not owner!)

Ray

It’s sort of been mentioned already, but I suggest just making your own gaskets. Either cut out the shape with sharp scissors, or place a piece of gasket material on the relevant surface and gently tap round the edges with a hammer till the gasket sheet breaks away (this method is very satisfying, and will give you exactly the right shape,)