Fuel Vapourisation

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MikeNash
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Post by MikeNash »

Pikey,
The "glass bowl" filters were standard fit on 1960s Ford Consuls and Zodiacs for the sound reason that then you quite often bought some water and crud with your fuel. Many garages in those days still had the steel tanks in ground that they'd had from the twenties, but these were replaced in the 60s and 70s so water and rust in your fuel should be a thing of the past. I certainly found one worth having in those days. In recent times I've not used it, but judging by the sludge recently in my carb, I reckon someone's selling me water again (at 107.9 p a litre too!) so the bowl's going back on.
So my advice is to put a bowl in if you've got one between the tank and pump. And put both pump and bowl on the engine bay "floor" to pressurize the riser pipe up to the carb, thereby reducing the chances of vapuor forming it. Regards, MikeN.
Morris Minor, the car of the future. One day they will all look like this!
bmcecosse
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Post by bmcecosse »

The SU carb is very tolerant of water/dirt - it has a relatively 'huge' fuel metering arrangment. Poor old Fords using ghastly Zenith type carbs had to have filtered fuel because of the (several) tiny jets in these fixed choke carbs. The filter CAN cause problems -by forcing the carb to hav to suck too hard - in turn causing fuel vapourisation! If you MUST have filter - best put it between pump and carb - but the filter in the pump will already have trapped the dirt - so it's a pointless exercise.
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Pikey
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Post by Pikey »

Many thanks for everyones replies

I think I may try as BMC suggests and take the in-line filter out of my fuel line.

I'll see if this makes a difference. The vapourisation is only a problem when the weather is really hot (not very often in britain) and Ive been stationary for a while, its never a problem on normal driving.

As my fuel line runs very close (maybe even touching the shock absorber crossmember) I may buy one of those stainless braided hoses from burlen. Now that I wont be maintaining a filter in that area Ive no reason for inspecting the hose and it may end up being damaged by the adjacent chassis edges.

Again many thanks to all.

Steve

Kevin
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Post by Kevin »

The vapourisation is only a problem when the weather is really hot (not very often in britain) and Ive been stationary for a while, its never a problem on normal driving.
Unfortunately its a fairly common occurence in our neck of the woods as well in slow traffic and hot days, the important thing to do is try and not let is stall otherwise you wont get it re-started for a while (good pump or not) I know of a couple of owners who had the grumpies kit some years ago and it didn't make any difference to the problem.
There are 2 other alternatives, the first can only be done if your engine block has the outlet on the side for a mechanical pump like the spridget or marina, as fitting a mechanical pump also involves re-routing the fuel line to a lower position as so eliminates the problem.
The other way is to fit something like a facet pump near to the tank although you sometimes have to fit a pressure reducer to lower the output.
Cheers

Kevin
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