Fuel Pump

[Stig]

I had to have a go at the fuel pump this morning after grinding to a halt only a couple of miles from my house There were sparks at the plugs and it didn't smell of petrol despite repeated attempts to restart it so thinks "Aha, fuel pump!". I found a lot of soot under the cap, not good. Cleaned the points and tried it again and lots of ticketytickety noise. The pump was really hot though, i.e. too hot to keep your fingers on. I would've thought there'd be no current if the points weren't working, I guess they could have welded in the on position. Anyone heard of this?

What's the expected life of a set of points? The pump was replaced 3 or 4 years ago I think.

I reckon the car was just playing up because I'd been ignoring it and driving the Sprite for the last week...

[simmitc]

Points fitted originally (ie 1971 & earlier) should last for 20 years / 150,000 miles. Points fitted in the last 5 years will last until they're just out of guarantee. Me cynic? Never.

[Stig]

Cynic you may be but this is the second replacement. I sent the first one back when it failed after about 2 months. I got the impression from the supplier (Bull Motif? ...can't remember) that the manufacturers weren't that 'customer focussed' as they pretty much had a monopoly on 'original' fuel pumps...

Hopefully my quick road-side fettling will be OK until I get a chance to clean things up with a needle file. Perhaps I'll do that the minute I get home, don't want it conking out with a car full of mates later tonight.

[bmcecosse]

Yes, clean and set the points annually. Is it the type with 2 contacts ? helps a bit if you put a radio suppressor on the pump - helps to stop the arcing. Maybe also the filter is blocked ? Sure fire way to avoid trouble is to carry a spare pump at all times - it never fails then !!

[chickenjohn]

Just out of interest- where do you wire the radio suppressor?? I guess this works much like the condensor- i.e. a capacitor that stops sparking across the points???

[aupickup]

all repro new stocks last months instead of years.

[ColinP]

to return to one of the original questions...

The pump was really hot though, i.e. too hot to keep your fingers on. I would've thought there'd be no current if the points weren't working, I guess they could have welded in the on position. Anyone heard of this?

The problem I had (and it sounds like yours) is that the points don't open (too much arcing/deposits etc). If the points are closed, then the electromagnet in the pump has current flowing through it continuously and it gets really hot!

That, in my view, causes the fuel to vapourise in the pump (hence the thump, thump, etc). Recent suggestions are to check/clean & regap the fuel pump points annually.

Colin

[Stig]

The contacts looked very pitted, "crater" would be a good description. I guess I'd better order a new set, I assume you need to set the gap/clearance/throw again after replacing them? I only took off the outer springy (double) contact and cleaned it with glasspaper.

There is already a capacitor there, I assume it's connected directly across the points (where else on such a simple circuit?).

Ho hum, something to add to my rather haphazard maintenance schedule.

[ColinP]

Yup,

New set a good idea (and I'm now keeping a spare set in the car as well) - try ordering 2 sets .....

Replacement is not difficult - but much easier with the pump out of the car! It's worth the 5-10 minutes unbolting the pump & fuel lines.

The gap should be 30 thou' - it's difficult to describe, but easy to see with the points assembled.
There's no need to change the throw etc - that's managed by the screw rod which should not need adjustment.

Happy motoring,

Colin

[paulg]

I had problems with the fuel pump too. I bought new points (not cheap) and fitted them . Still problems despite cleaning and setting several times. Obviously my mechnical skills were not up to pump reconditioning.
So I fitted an electronic pump (cost about 50 quid then). Since then no pump problems and it looks fine too.
The pump has seen off a few head gaskets, valves, a gearbox, suspension parts, numerous distributor points, a wing or two, headlining, brake parts, two exhausts and a front panel etc.
Probably the best "mod" I have ever made except the "modern" HT leads (not copper!) and dist cap. Together these two changes made the car very reliable indeed.
(I think I made the same post a few years ago!)

[Cam]

Probably the best "mod" I have ever made except the "modern" HT leads (not copper!)

So... what is the construction of your 'modern' HT leads, and what's wrong with the copper type?

[paulg]

Hi Cam! you are quick!
I found that copper wires and the way they were fitted using little, pointed screws always were susceptible to "leaks" and shorts. Looking under the bonnet at night revealed a lot of blue arcing.
In winter when damp (car was parked outside) many mornings were WD40 day!
I had replaced leads, suppression caps and dist cap several times!
It made the car a nightmare and too unreliable to use. After using the "carbon filament", or whatever the are , leads with push in connectors and a new cap (because of the push on leads) the car never needed WD40 again and had no arcing. It put the pleasure back into driving it. They also were better at suppressing radio interference.
Incidentally, I once (only once) used copper on a more modern ignition system - it melted. Moderrn HT systems seem to put out much more power.
I suppose if the car is garaged and dryish then the original kit is ok.

[Cam]

Oh right. I have never had that sort of trouble with HT leads. The 8mm copper cored ones I have on my 4-door have been fine for years:
http://potteries.mmoc.org.uk/Members_Ca ... 328_04.JPG

But the previous copper ended ones (that fitted over the spark plug contact only) kept vibrating loose:
http://potteries.mmoc.org.uk/Members_Ca ... 98_LHS.jpg

Well, at least you have solved the problem now and have a more reliable system!

[bigginger]

From what is the rocker cover in the first shot? Oh, and nice engine hooks BTW.

[TerryG]

It looks the same as my one so i would say MG Metro

[bigginger]

Aha!

[Cam]

Yep, MG Metro. It's my 'used for lifting engines in and out' cover. A rocker cover has to be used with those lifting 'eyes' to ensure that the studs don't bend.

I might alter them into a more conventional shape at some point...

[TerryG]

If you REALY want one i have a spare in my garage They dont have a breather on the top though so you have to get one of those breathers that attatches to the side of the engine (Excuse me getting realy technical there. hehe)

[Cam]

Yes, I have a spare one too, but it has not got the correct bolts (longer than standard). I think you can stil buy them though.....

[bigginger]

No, don't want one, just interested. I prefer the Maestro one, just 'cos it has a nice long wiggly tube to pour the oil in... Again out of interest, don't those hooks increase the risk of bending the stud - more leverage and all that?