Bulletproofing your Healey

[glemon]

The fuel system crud thing is a big reliability issue for many older cars, including the last Healey I had and my current Triumph, as well as my nephew's X1/9, etc. etc. Changing the fuel tank really isn't much different from changing the radiator is it? The radiator swap is on the list.

 

[RAC68]

According to Dave DuBois, a recognized SU Fuel Pump expert, "SU pumps are able to pass most debris right through them without causing any problems. The filters that are built in them are designed to stop rocks and small birds." (https://userwebs.donobi.net/sufuelpumps/Fuel_Pumps/SU_Fuel_Pumps_Facts_and_Myths.pdf).

I depend upon my Healey's original fuel filtration which primarily consists of screens in the pump and input of the carburetors and, to date, I have had no difficulty with debris in the fuel causing me to stop running. I do appreciate that those with older fuel tanks or experienced dirty fuel from a vendor may want to consider adding a fuel filter and suggest their installation be placed on the output side of the pump, possibly close to the carburetor feed line.

Happy Thanksgiving,
Ray(64BJ8P1)

 

[Michael Oritt]

Ray--

I wouldn't think to dispute Dave's advice. Nevertheless I like to have an inline filter that I can easily view and if necessary change. I have mine spliced into the fuel line inside the left rear wheel arch--admittedly on the suction side of the pump but in a place where if a line breaks, etc. it will not spew fuel onto a hot engine, exhaust pipe, etc.

If installing a clear plastic (non-conductive) inline filter between tank and fuel pump remember that the metal fuel line provides a ground for the fuel sender and it is necessary to reestablish ground via an additional wire from the sender body to earth.

Happy Thanksgiving all.

 

[RAC68]

Michael,

I truly understand your point and reiterate the fact that the metal fuel line form the tank to the pump provides the ground for the fuel level sending unit. The issue that Dave brings up, specific to the SU fuel pump, is that the flow of fuel is required for proper cooling of the SU pump coil and loss of flow through a blockage or air leak could cause the pump coil to overheat.

I have seen a number of instances where an air leak at a filter placed before the pump has caused lean or no fuel to be provided to the carburetor. A clue to this condition is usually provided by the continuous running of the pump. I agree that placing a fuel filter where you have (between pump and tank) has its advantages and the SU pump can function reliably in that configuration if installed properly and regularly monitored as you suggest. However, you may be an exception as I have found that most Healey owners don't even consider the fuel filter during maintenance...much less would pull a wheel to check its condition ... unless provoked by an issue. Any way you go, being aware of the positives and negatives puts one in a better position to make an intelligent decision.

All the best,
Ray(64BJ8P1)

 

[roscoe]

I did post a photo in my post. Do you still need one? All I did was find a threaded clevis, thread a double ended stud into the captive nut, made a cable with nico press sleeves and when I attach it I pre-twist the cable so that as the clevis tightens the cable un twists and it ends up being snug.

 

[steveg]

I did post a photo in my post. Do you still need one? All I did was find a threaded clevis, thread a double ended stud into the captive nut, made a cable with nico press sleeves and when I attach it I pre-twist the cable so that as the clevis tightens the cable un twists and it ends up being snug.

Jon - not sure what this is referring to. Could you please elaborate or repost the photo. Thank you.

 

[Michael Oritt]

Ray--

You said: "I have seen a number of instances where an air leak at a filter placed before the pump has caused lean or no fuel to be provided to the carburetor."

I'm not sure where you could mount a filter downstream of the pump except very near the firewall in the engine compartment, and the consequence of a leaky filter at or near the exhaust header would be a lot worse than lean or no fuel! As much as possible I like to have a fuel line make a continuous run from fuel pump to carbs or fuel log.

 

[RAC68]

Edited and somehow duplicated.

 

[RAC68]

Michael,

The filters I have seen mounted in the engine compartment were attached to the fixed metal fuel line on the input and the flex line on the output.

However, You may be right that placing a fuel filter in the engine compartment could be more dangerous as a leaking fuel filter mounted close to the carburetors could possibly leak, or even spray, fuel onto a hot exhaust and cause a fire. But then again, a stuck float could do the same.

As far as monitoring and maintaining the filter, I would expect these functions would be more likely performed if the filter was in the engine compartment as apposed to having to jack the rear to pull the wheel for checking.

Don't get me wrong, I have chosen not to install a filter and rely upon the screens that are part of the pump and carburetor inputs to remove contaminants. We are talking technology that was designed when fuel was not as clean as pump gas today and we are also talking about pumps and carburetors with rather large orifices. Yes, we can get bad gas but this is a very infrequent, if not rare, condition (at least so far for me).

All the best,
Ray(64BJ8P1)

 

[John Turney]

My filter is downstream of the pump and under the left rear seat. I have "rubber" fuel lines though, and a ground wire.

 

[steveg]

Wasn't previously aware of sender grounding through the fuel hardline. Ground wire to rear of trunk is easy bulletproofing.
Using bonded rubber sealing washers and hylomar -- bulletproofing against leaks.

 

[steveg]

Further bulletproofing: use of Facet pump with heatshield; re-routed fuel line to inside of frame rail away from exhaust. Clear filter for easy-view.

 

[roscoe]

To those who asked about the top bow security cable I've installed, there is a post on this thread that is on page 2 made on 11/20 with 3 photos. One shows the cable clevis. I made a 1/16 " cable with a nico press sleeve loop at each end. One is attached to a small tab that is secured onto the wood bow at the front to the top, the other is attached to a small clevis with a clevis pin that is threaded into one of the captive nuts that secure the dash mounted rear view mirror. I believe I could drive all day with both top latches unsecured and this would prevent the top from being blown back. It is easily removed for retraction of the top by pulling the clevis pin at the bottom loop. If I have the top down I just leave the clevis threaded down tight and it secures the mirror. It can be removed in a few seconds to install the original screw if desired. I also made some aluminum tabs that screw into the wood top bow that have little rubber bumpers that press up against the top of the windshield frame when I put the top up. They help align the top and keep it from having any looseness when the latches are engaged. Bear in mind, I don't know offhand if my install would work for anything besides a BN1 or BN2.

 

[RAC68]

I had added a ground wire to the cover of my fuel gauge sending unit, as Steve describes, even with my unsevered original metal fuel line between tank and pump.

If I ever decide to install a Facet rotary pump, I would configure it in-line and after my SU pump. In this configuration, a filter would be required for the Facet pump as a rotary pump is very susceptible even the smallest contaminants in the fuel.

Steve, the BJ8 fuel line is routed on the inside of the frame rail on the right side (opposite side of the exhaust location) of the car. I would maintain this fuel line routing and install the Facet pump as close to the SU as practical.

Ray(64BJ8P1)

 

[steveg]

I had added a ground wire to the cover of my fuel gauge sending unit, as Steve describes, even with my unsevered original metal fuel line between tank and pump.

If I ever decide to install a Facet rotary pump, I would configure it in-line and after my SU pump. In this configuration, a filter would be required for the Facet pump as a rotary pump is very susceptible even the smallest contaminants in the fuel.

Steve, the BJ8 fuel line is routed on the inside of the frame rail on the right side (opposite side of the exhaust location) of the car. I would maintain this fuel line routing and install the Facet pump as close to the SU as practical.

Ray(64BJ8P1)

Ray - the Facet gold box pump is not a rotary. It is a steel piston that oscillates in and out of a magnetic field (discussion on a previous thread). That said, it comes with a Ford-style filter on the input side.

 

[twas_brillig]

When I saw 'bullet proof', I immediately thought "kevlar"....
There's another thread on the site asking for suggestions as to 'Tasteful Upgrades', and I'd sure like to see folks adding their suggestions to that one, as it covers both the 'bullet proofing' and beyond. And I sure would like to see some way of having these types of threads summarized and placed where they are readily identified (but I don't know how that would best be done).
We haven't rebuilt our engine, but I'd want to get the overpressure 'bullet' and its mating surface lapped or whatevered when that happens, and the spring checked, to ensure that it was always properly controlling the oil pressure. We switched the reflectors on our BJ7 to being the turn signals and have the LED tail/brake lights - an attempt to improve the driver's 'bullet proofing' if not the cars. Putting a bit of dielectric grease on the connections may also be useful; plus an overflow capture system for the rad for if/when the rad cap fails (Highway to the Sun, many years ago - got a new rad cap in Kalispell). Doug

 

[Michael Oritt]

Doug--

Our moderator and "Austin Healey" magazine Editor Reid Trummel asked if I would send him an article submission based on this string. I will do so and am going to stick to the original parameter of making a car more reliable, as opposed to safer, more comfortable, etc. Perhaps you or someone else will choose to write a corresponding article covering those topics which would certainly be of interest to all of us.

 

[Randy Forbes]

Further bulletproofing: use of Facet pump with heatshield; re-routed fuel line to inside of frame rail away from exhaust. Clear filter for easy-view.
View attachment 46052

When the Healey archaeologists find our cars (yours and mine, Steve) they're going to be scratching their heads!

When I rebuilt my car, an early BN6 (L/942) I used 3/8" stainless steel instrumentation tubing along side the RH frame rail (and around the front of the engine, behind the front XMBR) similar to the way the factory did it on the later BJ (7? &) 8 cars. I elected to mount a Facet "interrupter type" pump on the bulkhead behind the RH seat, next to the battery. The original electrical circuit feeds the new pump, with the addition of a 5-amp aircraft-type (push-pull) circuit breaker mounted through the bulkhead behind the RH seat.

There's a Holley fuel pressure regulator and an inline filter under the hood, next to the brake/clutch fluid reservoir. The pump itself has a filter built into the inlet side, accessible via the hex-ended cap shown above.

Perhaps not in the complete interest of bulletproofing against the rubber diaphragms deteriorating in the SU carbs, the fuel system terminates at the connections to three (3) 45 DCOE Weber carbs. All this is being fed from a 28.8 gallon aluminum fuel tank in the original's location. The reliability aspect I suppose, is being able to traverse wide open spaces were gas stations are fewer and farther between (thinking west Texas, NM & AZ).

Perhaps the most reliable aspect of the modifications to my cars fuel system was to completely throw out the stock throttle linkage, and opt for a more direct connection; conventional floor-pivoting pedal (with reasonably long travel) using a single vertical rod connected to the horizontal rod attached to the carbs.

The majority of the fuel system in BN6L/942 can be seen in this album: https://spcarsplus.com/gallery3/index.php/Healey-at-home/Fuel-System

 

[RAC68]

Hi Steve,

Thanks, I stand corrected. However, the fact is the Facet pump is sensitive to contaminants in fuel and requires an input filter for protection.

What's so interesting, in context of our “Bulletproofing” topic, is that the Healey's technology is not significantly sensitive to fuel contaminants and could easily and reliably handle the dirty fuel of the day. The protection originally placed within our fuel systems consisted of screens on the input side of the SU pump and carburetors to block the passage of quite large pieces of foreign matter. Today, our pump fuels are much cleaner, however, the inclusion of modern technologies (i.e. Facet pump, etc.) into the fuel system now requires we also add a filter to remove relatively fine contaminants from our fuel flow or risk the failure of this unit (i.e. Facet backup pump). So, are we improving the operational reliability of the fuel system or ... increasing risk and adding to the failure potential.

Would it be better to incorporate a backup "SU Fuel Pump" having the same insensitivity to fuel contaminants or, as many have done, add higher levels of filtration to our fuel system for increased security of clean fuel delivery to our carburetors. I often wonder if, by modernizing certain systems in our Healey we may not be improving it but opening it to unanticipated issues.

Don't misunderstand, I do believe there are some technologies that are beneficial and desirable to add and will improve reliability and serviceability. (i.e alternator, electronic ignition, etc.). However, their addition carries its own risk but eliminates more and the substitution results in a net reduction of failure probability.

Just some thoughts,
Ray(64BJ8P1)

 

[GregW]

What's so interesting, in context of our “Bulletproofing” topic, is that the Healey's technology is not significantly sensitive to fuel contaminants and could easily and reliably handle the dirty fuel of the day.

While the pump and carbs can "handle" contamination, remember that anything that doesn't get filtered goes into the combustion chamber. Particles like rust can wear the cylinder walls, rings, bearings, etc.