13 replies to this topic

[mookalarni]

After a recent fueling debacle/gummy carb syndrome, I'd like to install an inline fuel filter.

I've searched in the posts and most folk suggest course filter before the pump and disposable paper before the carb.

I'm not sure whether it's the original set up (I feel like it will be) but I've got solid metal fuel line from the fuel pump up to the carb and then a short piece of rubber hose connecting the metal to the float bowl. I've not got enough room to install fuel filter there due to the metal pipe and it's got no give in it. Can I replace the whole length from pump to carb with either flexi hose or rubber fuel pipe and put the filter in along the way? Any safety concerns? If okay to do so, which material is better?

Thanks all

[mab01uk]

I assume you have a Mini with a mechanical pump on the back of the engine and not an earlier Mini with an electric pump on the rear subframe.

It would not be a good idea to use a rubber or flexible hose all the way from the pump to the carb as it is very near the hot exhaust and manifold so would be a fire risk.....which is why the factory fitted a rigid metal pipe in that area.

A fuel filter can be fitted between the metal pipe and the carb or on the bulkhead but it can be tight for space with two short flexible pipes each side of the filter....alternatively some fit one at the other end of the car as suggested in links below, although access is not quite so easy. If below boot floor it must be away from the hot exhaust.

Best Fuel Filter Location:-

https://www.theminif...ilter-location/

 

Inline Fuel Filters And Placement:-

https://www.theminif...-and-placement/

Edited by mab01uk, 08 October 2024 - 02:39 PM.

[mbolt998]

I put mine in just before the float chamber. Connected to the end of the original steel pipe you refer to with a short bit of fuel hose, and then there's another short bit of fuel hose between the output of the filter and the float chamber. This means the steel pipe (which I didn't bend or shorten or anything) is a bit more hanging out to the left. I attached it to whatever else was around there with a zip tie so it doesn't move around. I think I have the same setup as you: mechanical fuel pump attached to the engine block.

[mookalarni]

Yeah it's a mechanical pump on the back of the block. Thanks guys I'll have a go at fitting to the existing solid lines.

[whistler]

I fit mine under the rear subframe in the rubber hose from tank to steel pipe.

[mbolt998]

I fit mine under the rear subframe in the rubber hose from tank to steel pipe.

That's probably a good idea. The nice thing about having it under the bonnet is, because it's made of glass, you can see lots of juicy fuel in there or not when diagnosing potential starting issues. But it does mean bits of rust might go into the fuel pump.

[Shooter63]

Yeah it's a mechanical pump on the back of the block. Thanks guys I'll have a go at fitting to the existing solid lines.

I'm just replacing the hard line on my Mrs mini, if you can wait until the weekend I'll post the bend points and straight run dimensions, it's all done but I'm waiting for some heat shrink tube to cover it with.

Shooter

[mookalarni]

Yeah it's a mechanical pump on the back of the block. Thanks guys I'll have a go at fitting to the existing solid lines.

I'm just replacing the hard line on my Mrs mini, if you can wait until the weekend I'll post the bend points and straight run dimensions, it's all done but I'm waiting for some heat shrink tube to cover it with.

Shooter

That would be extremely helpful, yes please. Won't get a chance to mess about with it until next week now anyway so that works out well. Thanks for your help.

[84 City E]

 

I fit mine under the rear subframe in the rubber hose from tank to steel pipe.

That's probably a good idea. The nice thing about having it under the bonnet is, because it's made of glass, you can see lots of juicy fuel in there or not when diagnosing potential starting issues. But it does mean bits of rust might go into the fuel pump.

 

When you say your fuel filter is made of glass, do you mean the type you can unscrew the ends and clean? Dont want to worry you but ive seen a few of those fail and leak from the end plates, only one instance resulted in huge fire, but id still be binning it and just buying the plastic disposable type and change when needed.

[mbolt998]

 

 

I fit mine under the rear subframe in the rubber hose from tank to steel pipe.

That's probably a good idea. The nice thing about having it under the bonnet is, because it's made of glass, you can see lots of juicy fuel in there or not when diagnosing potential starting issues. But it does mean bits of rust might go into the fuel pump.

 

When you say your fuel filter is made of glass, do you mean the type you can unscrew the ends and clean? Dont want to worry you but ive seen a few of those fail and leak from the end plates, only one instance resulted in huge fire, but id still be binning it and just buying the plastic disposable type and change when needed.

 

 

I don't know if you can unscrew the ends, I haven't tried! Thanks for the heads-up. Will have a closer look. It is in a good spot to spray fuel all over the exhaust manifold if it does leak. I think I got this one from minispares:

 

http://www.minispare...uel/PRO804.aspx

 

It does look like it probably does come apart or why did they put those hex bits on it?

 

 

[Shooter63]

Yeah it's a mechanical pump on the back of the block. Thanks guys I'll have a go at fitting to the existing solid lines.

I'm just replacing the hard line on my Mrs mini, if you can wait until the weekend I'll post the bend points and straight run dimensions, it's all done but I'm waiting for some heat shrink tube to cover it with.

Shooter

That would be extremely helpful, yes please. Won't get a chance to mess about with it until next week now anyway so that works out well. Thanks for your help.

OK here we go, all measurements taken as if you are looking from the rear of the car
90 degree bend leaving a 75mm tail to fit the rubber hose
135mm 90 degree bend to the right
90mm 90 degree bend towards the front of your car
1095mm 90 degree bend to the left ( this is where it turns across the floor pan)
135mm 90 degree bend ( the tube will now the running towards the front of the car)
260mm 45 degree bend up ( on from this the the goes behind the rack etc)
All these dimensions are outside to outside as I have no idea what the bend radius is of the tool you are using. I'm going to presume that all mark of minis had the same run, what is different is if you have an early car with an electric pump. To me the most critical one is the first turning bend which comes from behind the subframe. I found that when replacing the line pre form it, Jack the car up high, fit the pipe from the back letting the pipe droop and move around as you get the over the subframe part in first, then feed the front part up behind the front subframe, don't forget to put some form of sleeving over the pipe where the clips are, as this is the point where they rot, I have covered the complete pipe in shrink tube except where the rubber hoses fix.
You may have a better way of doing it but this is how I did it.

Shooter

[unburntfuelinthemorning]

When you say your fuel filter is made of glass, do you mean the type you can unscrew the ends and clean? Dont want to worry you but ive seen a few of those fail and leak from the end plates, only one instance resulted in huge fire, but id still be binning it and just buying the plastic disposable type and change when needed.

 

 

 

The plastic ones can have problems too.  Years ago I was driving and wondered what was causing the petrol smell.  I opened the bonnet to find fuel being sprayed out of a pinhole in the side of one of those generic plastic fuel filters that I'd fitted.  It was spraying directly onto the exhaust manifold and instantly evaporating.  As I was in the folly of youth I thought that as it hadn't caught fire yet it'd be alright, shrugged my shoulders and drove home.  

[dotmatrix]

I've searched in the posts and most folk suggest course filter before the pump and disposable paper before the carb.
 

 

on my a-series daily with HIF carb I have a small see through cheap filter in the engine bay near the carb.

it need to be changed once a year when dailying the car.

 

on my race a-series I have a bigger cheap filter where the fuel exits the tank, between tank and pump under the car and a regulator/filter in the engine bay.

also this cheap filter needs to be changed once in a while

[Spider]

,,,,,, because it's made of glass,

 

I'm not sure if this is applicable to the type you have however all the versions of these that I have seen, while serviceable as well as being see through, they are a strainer rather than a filter. Lots of 'stuff' gets through them, most of which you'd rather filter out.

 

You'll find you can go for a very long time, years, without a filter blocking issue, then when it does block, they tend to do so on a big way from the load of contaminated fuel you just bought and you'll only find it's blocked when you've drive 1/4 of a mile down the road, you can rest assure that it'll be on a busy road and hardly a convenient place to sort the filter out !

With a Mechanical Pump, while in many ways it makes sense to fit them between the Tank and the Pump they can be fitted under the bonnet in that part of the plumbing, on the line between the fuel line and the pump. Extend that up, in rubber hose, to your filter that you can cable tie to a heater hose or other bracket around the bulkhead, then run a rubber line back down to the pump.

 

I say above 'in many ways'. I fit them between the Pump and the Carb as some disposable filters are actually designed to work under pressure and usually by-pass when under a vacuum. The other advantage of plumping them this way is if the filter becomes blocked and you don't have a new filter with you, you can disconnect the filter, plumb the feed from the pump to the filter outlet, pump some fuel through it to back-wash it and then refit it in the normal way. I usually do that as I've found with a fill of contaminated fuel, you'll go through a LOT of filters in quick succession if you replace them, pretty much until that load of fuel is all used up.