Jump to content

GT6 Fuel Pump


Ian Cooper

Recommended Posts

Hi all.

Just a quick ask please.

I'm looking to replace the standard fuel pump (gaskets and olives would be good too) on my MK2 GT6 and wondered if anyone can recommend the best supplier, and that includes 'Rimmers' if you think they may be offering the best, though I know they won't be the cheapest! Or maybe a supplier to avoid like the plague, all advice welcome.

Cheers folks, and may I be the first to wish you all a Merry ūüéĄ

Link to comment
Share on other sites

Hi, fuel pumps like many components for our cars these days have limited demand so there tends to be just one or two non original companies making them quite often in places where labour is cheapest. This improves availability and cost but means all UK suppliers stock the same items although they will of course each charge different prices. The downside is that manufacturing quality control can be lacking and obviously with this supply situation it can affect an item no matter where you get it from.

In the end it comes down to which suppliers might handle problems best weighed against their prices and in my case its the latter that wins everytime...

Link to comment
Share on other sites

+1 for Canley classics 

as there are so many problems with replacement pumps producing excessive pressure its worth fitting a gauge in line to check what the output is 

we dont have a list of rogue pumps  and many suppliers supply each other which is where the price hikes can come from as all want a share of the mark up

if you end up with flooding the cures range from adding more gaskets to reducing the spring length 

2.5psi is about right   3.5+ will overload the float needles 

Pete

Link to comment
Share on other sites

Do a search on this section for "fuel pumps" and read what we all have experienced. I ended up replacing the valves in the original glass bowl one. You can see what is going on with that version.

There is a low pressure electric pump mad by Huco, but you should fit a safety device to shut fuel off if you have an accident should you choose that solution. Mechanical pumps stop when the engine does. Electric ones do not.

Having stated that, the Morris Minor and most BMC cars used electric pumps with no such safety device.

Link to comment
Share on other sites

Chances are this has been covered before?, But in my mind the issue of overpressure on the AC type mechanical pumps would be down to the Spring rate?. The induction of fuel is made when the Diaphragm is drawn down, the spring ensures the return. A "weaker" spring would / should lead to less pressure? or am I oversimplifying?. Reducing the stroke would merely reduce the volume of fuel.

Pete

Link to comment
Share on other sites

I think its both because any spring needs increasing force to progressively compress further so if the fuel pump's is only compressed a little by the cam and lever logically when released it will apply a lower force to whatever is resisting it (in this case fuel and the float valves)....

Link to comment
Share on other sites

It depends on how sensibly the spring is specified. The sensible option is a weak spring that needs compressing to fit. In that case, the stroke mostly governs the flow and has little effect on pressure. If the spring is stronger but its rest length is the same as the fitted length, then a shorter stroke makes much more difference to the pressure for the reason johny gives.

Link to comment
Share on other sites

Yes as I say in the old days when thousands of these pumps were being made it was economical to make a specific spring but now the production is very limited the manufacturer just gets the cheapest off the shelf spring they can find possibly from a washing machine or car seatūüė≠

Link to comment
Share on other sites

You can simply swap the top half of the pump (which includes the valves) and leave the lever / spring etc assembly on the block. This preserves the original output pressure if you encounter any problems. It's easy to replace the diaphragm at this stage too.

Gully

Link to comment
Share on other sites

  • 2 months later...
On 15/11/2022 at 15:15, Pete Lewis said:

+1 for Canley classics 

as there are so many problems with replacement pumps producing excessive pressure its worth fitting a gauge in line to check what the output is 

we dont have a list of rogue pumps  and many suppliers supply each other which is where the price hikes can come from as all want a share of the mark up

if you end up with flooding the cures range from adding more gaskets to reducing the spring length 

2.5psi is about right   3.5+ will overload the float needles 

Pete

Adding more gaskets, is there a suggestion as to how many additional gaskets are needed?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
√ó
√ó
  • Create New...