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MG MGB Technical - Fuel Filter

I've just removed a blockage from the float for the third time & it's getting a bit tiresome. The fuel filter doesn't appear to have a small enough mesh to trap particles from the tank. Is there a better unit available, the one I am using now is new from MGB hive & is the plastic in-line type. I looked at this one from Moss
http://www.moss-europe.co.uk/d945ac.html?assoc=111321

and the mesh would appear to be fine enough, & I can clean it out when required....any thoughts?


P M Gregory

PG, It's probably that the fuel line is disintegrating AFTER the filter. Any decent filter has a small enough mesh to remove particles big enough to cause float chamber problems.
Allan Reeling

PG - The filter is not the problem - if there is debris coming from your tank, the tank needs to be cleaned or replaced. All the filters in the world are not going to correct a problem in the tank. Cheers - Dave
D W DuBois

Ok,

All new hoses & a new line from tank to filter so that hopefully isn't the problem.

pat
P M Gregory

Are the new hoses ethanol resistant?
Dave O'Neill 2

Pat - If you have an OEM SU fuel pump still in your car, a filter of any kind is a no-no, See the article, SU Fuel Pumps Facts and Myths in the SU Fuel Pump Articles section of my Homepage at: http://homepages.donobi.net/sufuelpumps/
If you have an after market fuel pump in your MGB, ignore the above. Cheers - Dave
D W DuBois

Dave O:
The hoses are again from MGB Hive so I don't know about Ethanolicity (is that a word)
Dave D: It is a standard SU, refurbished with electronic points conversion.

The filter is shown in the manual and is an in-line unit just before the carburettors so was fitted as standard.

My problem is that I don't trust the filter, some of the parts I have installed are of poor quality (that isn't a dig at the supplier)and my thinking is that a better quality and/or more expensive item will do the job better, I have tended to use Moss more & more as their parts just seem to be better made. I appreciate that you 'get what you pay for' but I'm beginning to agree with other posters that the drive for 'cheap' has compromised quality to a very high degree.

Some of the particles I found in the float bowl were grit sized I would expect even a mesh filter to stop those!

Pat
P M Gregory

Some multi-layer ethanol-proof hoses have caused exactly the same problem for someone elsewhere. The inner layer is so fragile than even pushing it onto the spigots of filter and carb Tee and ports was enough to damage it, and get large lumps in the float valves and chambers, as well as in the filter itself from the hose on the supply side. He's gone back to 'conventional' hose.

It needs fully flushing-out by first directing a hose connected to the pipe from the pump and directing that into a clear or translucent container, switching on the ignition, and pumping until there are no bits. If it continues to have bits then they are coming from further back, but SU pumps have filters as well so you shouldn't be seeing stuff coming from the tank anyway. Add a new filter and test again, then a section from the filter and test again.

You say the filter was factory provided which indicates you have HIF carbs, these are different to the earlier HSs in that the fuel supply goes through the front carb to get to the rear carb, so you have to flush that out as well, and flush out the passages in the carbs themselves.



Paul Hunt

Pat,

Put my jacket and beanie on to go out to the garage to check this - you wouldn't credit the weather we are getting here at the moment.

On my '69 I have fitted a Ryco - Z91 on the filter case, Z91S on the packaging. Made for Nissan and Toyota of the 1971 on era.

Paper filter in a plastic case. They work. I have used Ryco oil, air and fuel filters for 40 years. A quality product that has an esteemed place in aftermarket supply here in Oz. They are made, I believe, by a New Zealand company - Gud. Probably now around $10-15 here today - some years since I purchased.

Gud have a good website, Google Gud filters NZ. I believe they are available in the UK/US though may also be obtainable direct. I buy here from auto stores.

Any hose/line problems from the filter to the carbs would need to be sorted on the merits of the case.

Regards
Roger
R Taylor

This thread was discussed between 20/04/2015 and 21/04/2015

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