A fuel delivery failure will likely trigger the need for your MGF/TF Fuel Pump Replacement project. Written by Mark Jones the North American MGB Register’s Post Abingdon registrar. There’s also a video available, by Gregory Elgood, that may help with visualization of some of the written steps/parts.
Tools & Preparation #
Aside from the usual wrenches and sockets, there are a few tools you will need, or should have, to do this job:
- Fuel pump locking ring wrench. You can make your own like I did. Or purchase one. Several 90’s vintage Land Rover vehicles used the same locking ring. Online I found that a locking ring wrench is available from Paddock Spares, part# PM353 and Rovers North, part# RNT0014. This wrench will also work on the MY2000 onward locking ring.
- Hose clamp pliers. The pliers specifically made for constant tension hose clamps are indispensable. Both the basic and the cable-type pliers.
- Soldering gun/iron and heat-shrink tubing.
The Process #
Here’s how to tackle this.
Getting to the Fuel Pump #
Remove the engine access panel, located under the rear of the soft top. Next to access the fuel pump unit, remove fuel pump’s metal access plate. This is on the left-hand side of the engine area.
Remove the electrical connector, then remove the breather pipe (black rubber pipe). Be sure to push/pull it almost completely out of the fuel pump area. Disconnect the green and orange fuel pipes (quick disconnects like on the fuel filter outlet).
Unscrew the fuel pump locking ring. It is best to use a locking ring wrench that engages the knobs in the locking ring. If you use a screwdriver, chisel or prybar, these items will damage the knobs.
Removing the Fuel Pump #
You must remove the float arm first before removing the pump unit from the opening. There is a small plastic clip that you need to release the float arm from. Unclip this using a small screwdriver.
To replace the pump, both fuel hoses (pump discharge and return) will need to be replaced. Use 5/16” inside diameter fuel hose. It is not necessary to use Fuel injector hose. The maximum injector pressure of 3.5 Bar (51 psi) is below the rating of most fuel hoses. The return hose certainly does not need to be fuel injector hose. Note that the pressure in the return hose will be no more than a few psi.
Be aware that fuel injector hose is very stiff and much harder to clamp securely to the pipe on the pump unit. If not secured properly it will come off. If you do decide to use fuel injector hose on the high pressure side of the pump, keep this in mind.
When installing new hose, very little extra fuel hose length is needed. The pump unit will be compressed in the fuel tank. So this means that there will be no stress on the fuel hoses. It is recommended that you use fuel injector hose clamps on the high pressure-side of the pump. Make sure that the hose clamps are tight. I have seen examples of a replacement hose that had come off. No fuel was being sent to the injectors causing a no start condition.
To remove the fuel pump, you need to separate the swirl pot from the pump unit. There are four tabs on the pot that can be carefully removed by using a screwdriver.
Replacement Fuel Pump #
The fuel pump itself can be purchased from the normal sources in the UK. However, it does cross-reference to a couple different pumps available in the USA/Canada. The more commonly available one is KEMSO, part number 10912. Alternatively the Quantum Fuel Systems, part# QFS-341FT, which is for a 2002-2203 Chevy Avalanche. Both the KEMSO and the Quantum Fuel Systems pumps flow rate are higher. Their specifications are approximately 340 L/hr at 3 Bar (44 psi). Whereas, the original pumps are 174 L/hr at 3 Bar (44 psi). But the replacement options specifications align with the high performance fuel pump offered by Mike Satur. The pump’s wiring connector is different, which the replacement comes with.
The replacement pump from UK suppliers, comes with a filter that fits to the base of the pump. Just like the original. You must reuse the plastic piece with two rubber feet that is on the bottom of the original pump. This piece fits into slots in the bottom of the swirl pot, locating the pump within the swirl pot.
A couple of cautionary points with using pumps available in the USA/Canada. It may mean you need to clean and reuse the filter. Additionally, although the Kemso does fit and work, it may not last very long. In one case where it has been used to replace a faulty original pump, the Kemso pump failed within a year of use. The use of the Kemso pump should probably be seen as a stop gap solution until one can source a known, good quality replacement from the UK.
Reinstalling the Fuel Pump Unit #
Ideally, use a new seal, NTC5859, when reinstalling the pump. Fit the new seal to the tank. Also and lubricate the inside of the seal and the body of the pump where it will meet the seal. Petroleum jelly is a recommended lubricant. This should allow the pump assembly to slide in without disturbing the seal.
If the old seal is to be reused, it is best to place the seal on the pump assembly. Then push the assembly into the tank. It’s likely the reused seal is too soft to fit to the tank first. It may just slide out of position while refitting the pump unit the tank.
Reinstalling is somewhat difficult. Not only do you have to angle the pump assembly at approximately 30 deg angle, but also maneuver the assembly in the tank so that the unit’s base (swirl pot) is in contact with the tank’s wall and the circular indentation in floor of the tank and then compress the assembly, which ensures the unit’s base stays in contact with the tank floor and won’t move. In my limited experience, it takes several attempts to get the pump unit into the exact spot. Also make sure that the arrow on the top of the pump unit is aligned with the fuel tank’s welded seam. And don’t forget to reinstall the float.
Once the unit’s base is in the correct spot, you need to push down on the top of the fuel pump unit to compress the pump unit’s spring. Simultaneously you need to seat the top of the fuel pump into the tank seal. Then reinstall the locking ring and tighten to 45 Nm (33 ft-lb).
Reconnect the fuel lines, vent hose, electrical connector, fuel pump cover, etc. and you will be ready to test fuel delivery.
Video Overview #
Having read the instructions, this video may be useful to help those who find visual materials helpful.
Other Materials #
I’ve built this website and spent time on the knowledge base to bring together a lot of information I have collected from around the internet. The intent is making it easy to find rather than having to know about and have skills with search engine query terms to get what you were looking for. Please make use of the knowledge base.
