Fuel filter issue!

This is the 2nd issue I had when I went for a drive the other day !
Nice hot sunny day , car was a bit lumpy from cold , as I adjusted the mixture screws (home made) on the HS8 carbs , as the last time I took the car out , it was fine until I come in to some traffic , stop start stop start , car was running lumpy , I thought maybe over fuelling , I checked the plugs , had a bit of soot on them !
Any way car was running fine , till I hit traffic again , same thing , engine running lumpy , just would not clear !
So I pulled over and had a look under the bonnet , To my surprise the glass filter chamber was only 1/4 full :thinking:
I cracked the nut on the outlet side , and could hear pressurized air coming out !
Did the nut up and started the engine , still had air in the top of the glass bowl , maybe 1/4 down from the top !
Carried on driving to the café for food and drink , car ran a little better .

After about 1 1/2 hours I set off, car ran 100%, gave it some stick on the M20 , as in overtook everything :laughing:, high speed for a good 5 miles , and all the way back home , car ran faultless .
Had a look under the bonnet , fuel was still about 1/4 down from the top , and noticed that drip at this time !
So I am thinking , the engine running lumpy was because of lack of fuel , not sure why , but the stop start driving made the fuel low in the glass filter chamber , running fast filled it up a little .
Maybe fast engine speed was sucking fuel through a dirty filter .
So had a look on line for a new fuel filter , I don’t like them paper ones as had them in the past , that spring collapses then in time , did have a plan to add small metal rods up the sides to stop it collapsing , then I remembered there is another kind of filter , Brass gauze type , as the price is lower then the paper ones , and you can wash the gauze out and re use it , I am doing my bit to save the planet , :rofl:
So fitted that today , started engine , glass chamber is full , stayed full with hot engine , and revving engine up now and again , just need to take it for a test run now , see how it runs , after being in traffic !

Glass bowl , on side of road

New fuel filter .

Glass bowl with engine hot , after checking for leakes !

The paper ones can either be unsuitable, or not fitted properly

There is an explanation by Peter Crespin somewhere in the archives

This is the one I took out , time before I fitted an Origanal kind .
From what I can see its just a poor design , the spring holds the filter to the top , so the filter paper is under pressure all the time !

My 1965 3.8S never had the paper filter in the glass bowl. I understand these were not always used from the factory.

1 Like

The paper one’s are a crap replacment , for the Origanal AC filter !
Like this I just took out , managed to find some new old stock ones a few years back !


There’s a corvette filter that might fit. Google bundt cake filter corvette (was it c1 or 2?). The paper filters are absolute crap. And incorrect because the crud is collected on the inside unless the flow direction is reversed. The mesh / gauze filter is good too. Anything is better than the paper.

I have air in the filter sometimes but not like that…

I think I will revert to a mesh filter, as the paper ones are overly expensive anyway

I guess one alternative would be to trim the existing (or replacement) spring so that it exerts only minimal pressure on the filter body

I recall from Crespins note that more than one paper filter is sold masquerading as correct, some are some are not, not easy to tell

I believe the paper was only fitted from ~1967 onwards

Another option is to remove the filter from the AC filter housing , and place this kind between the outlet and the carb inlet .
They are only £6 odd for 2 ,

Any one who want’s an original one , just see this on e-bay at £9.50 , UK !

Not AC and not £10, but GF124 works correctly and looks good.

1 Like

Look’s good David , but doubt it’s available in the UK :thinking:

Well managed to take car out this week , fuel issue looks to be ok now , fuel bowl full !
Still have a drip from that heater valve 0 ring , going to try drying every thing off and applying some silicone sealer , on the valve and the heater box then on the 0 ring, replace the valve , but not doing the 2 screws up tight till the sealer has dried

1 Like

Yes, allowing a sealant to set before a final tighten has proved very successful for me over the years. As to fuel filters, I use the ‘cheap as you like’ inline fitted between tank and fuel pump and change when the oil is changed - every 2 years / 3000 miles or so. The ‘original’ engine bay filter always looks okay, and has the gauze and paper elements which is changed less frequently.

As one who thinks outside the box , thought I would try some PTFE tape , as it was such a nice day and wanted to go for a drive !
Come back and guess what :grin: drip still there :disappointed: lol
Will try the sealer today !

If it’s the same as E Type, I used a slightly bigger O ring. Maybe I also cut a much fatter one down. RTV feels bodgy…

I did look , but have nothing like the size , id needs to be the same to grip the pipe !
I did wonder if a gasket between the 2 flat surfaces may help :thinking:

I did a write-up on the various available filters for E-Types, should apply here as well. If you’re using the original “bundt cake” filter, be aware that the old fiber washers aren’t really safe for ethanol fuels. If you can’t find a fuel-safe o-ring to replace the washer, it’s probably just as well to omit it entirely, since it probably isn’t very effective.

This isn’t a good place to put an inline filter. It has the effect of lowering pressure before the fuel inlet, and can cause vapor lock. The most you want between the pump and tank is a bronze mesh to block gross particulate matter.

1 Like

So far, (only 20+ years of ownership of course), so good.

1 Like

Took car out for a drive yesterday , another nice hot day , parked up when got home , small puddle of blue water under the car , that bloody 0 ring !! :rage:
But no , my fault , left the cap lose on the expansion tank :roll_eyes:
Good news is the 0 ring was ok this time :rofl:
I know I know , there was no pressure lol
The expansion tank was full , just checked again , expansion tank is empty , and rad is about as full as it would be with no expantion tank !

Were you doing almost 90 at just over 3000 RPM?
Nice. Must be in overdrive?