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Conference terri::cars_uk

Title:	Cars in the UK
Notice:	Please read new conference charter 1.70
Moderator:	COMICS::SHELLEYELD

Created:	Sun Mar 06 1994
Last Modified:	Fri Jun 06 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	2584
Total number of notes:	63384

1111.0. "Surging, falling back, surging...." by RDGE44::JONESK (Yep you sure are) Wed Jun 13 1990 12:26

    I was coming down the M4 this morning at about 75 when suddenly
    my MGB began to "stutter" as though it was losing power/something
    for an instant.  It felt at first as though I was running out of
    fuel as it surged on then fell back, surged on, fell back etc..
    (NB. My fuel gauge hassn't worked in months.)
    
    I slowed down to about 65 but the same thing occurred.  Luckily,
    this all happened about 1 mile away from junction 12.  I came off
    at the junction and hence slowed down.  The surging cleared up.
     At low speeds, it's fine.  It idles over when stationary and there
    were no differences in its pickup or revving from the junction to
    DEC Park.  
    
    Is this a problem?  If so, any ideas what it is?  I may have thought 
    that the fuel line was becoming blocked due to low fuel level/general
    gunk in fuel-tank but I'm pretty sure I have plenty of fuel.
    
    Is it worth a blast of Redex?
    
    Kris.

T.R	Title	User	Personal Name	Date	Lines
1111.2		ANNECY::MATTHEWS	M+M Enterprises. Thats the CATCH	`Wed Jun 13 1990 13:08`	9
	I would suspect the fuel pump, or perhaps the the petrol filler cap is sealing too well. With the MGB, the pump is under the rear wheelarch, so unlikely to get hot. However, due to the rather large distance between the pump and the carbs, a weak pump may not be able to supply the fuel quickly enough ... Mark
1111.3		RDGE44::JONESK	Yep you sure are	`Wed Jun 13 1990 13:42`	12
	I replaced the pump about 6 weeks ago! On Monday I filled up the tank in Reading with petrol. I think I may have overfilled it in fact. After coming off the M4, and driving through London, after about 5 mins there was a terrible smell of petrol. When I got home 20 mins later, I inspected the Petrol filler cap and there was fuel all over the bumper beneath it. This didn't happen yesterday however. Kris.
1111.5	F pump again	HAMPS::WILSON_D	string	`Wed Jun 13 1990 14:39`	8
	From experience years ago with an E type. Err the Morris kind , not the Jag.... .....check the earth return on the fuel pump. A dirty connexion is very difficult to diagnose. DejW
1111.6	The condenser ?	SYSTEM::BOOTHE		`Wed Jun 13 1990 14:41`	6
	I had a similar problem on my Fiesta - everyone said it was the fuel pump, but it turned out to be a faulty condenser. Karen
1111.7		RDGE44::JONESK	Yep you sure are	`Wed Jun 13 1990 15:30`	3
	Would the symptoms occur at only high speeds if it were the condenser? Kris.
1111.8	Filth ?	JUMBLY::DAY	No Good Deed Goes Unpunished	`Wed Jun 13 1990 15:34`	7
	Same thing happened to me when I ran an MGB. Fuel Pump in my case - old and tired. Be worth checking the connections on your new one. Other favourite is straightforward filth. Either in fuel line itself or in carb - a cleanout of which would do no harm anyway. m
1111.9	Check tank connection	VANILA::LINCOLN	The sun has got his hat on	`Wed Jun 13 1990 15:51`	8
	If it's a fuel pipe blockage, and it sounds as if it is, the most likely place is connection of the fuel pipe to the tank. Tanks tend to rust internally and it accumulates in the bottom which is where the connection is (usually a banjo). If the tank is allowed to run dry this exacerbates the problem. -John
1111.10		ANNECY::MATTHEWS	M+M Enterprises. Thats the CATCH	`Wed Jun 13 1990 16:42`	8
	If you replaces the pump, it could be that one of the banjo bolts is loose and that the pump is sucking air rather than petrol. It could explain why you can smell petrol too. If not, the tank breather, and pump breather are worth a check. These both emerge in the boot. Mark
1111.11		RDGE44::JONESK	Yep you sure are	`Wed Jun 13 1990 17:15`	4
	But why did it happen at high speed only? Surley if there was a blockage or something, I would get the same effect at 30 mph too??? Kris.
1111.12		JUMBLY::DAY	No Good Deed Goes Unpunished	`Wed Jun 13 1990 17:17`	2
	More Speed => More Fuel => More Suction
1111.13	Check the Condenser	MACNAS::BMULQUEEN		`Wed Jun 13 1990 17:31`	6
	I wouldn't discount the condenser. I had the same problem with my Anglia. The condenser was fairly new but the voltage rating was wrong (12v instead of 6V). Anyway one new condenser and she hasn't spluttered since. Billy
1111.14		RDGE44::JONESK	Yep you sure are	`Wed Jun 13 1990 18:20`	2
	what sort of a job is the condenser? cost/time etc?
1111.15	No way jose	VANILA::LINCOLN	The sun has got his hat on	`Wed Jun 13 1990 18:51`	5
	For every faulty condenser that is replaced, 50 good ones suffer an early demise in the vain hope that the real problem will go away. -John (feeling very cynical today)
1111.16	Easy!!	IOSG::MARSHALL	Argle Bargle IV	`Wed Jun 13 1990 20:48`	10
1111.17		ANNECY::MATTHEWS	M+M Enterprises. Thats the CATCH	`Wed Jun 13 1990 21:34`	11
	re: .16 You missed the "watch screw holding condenser dissappear inside the distributor, requiring the distributor to be dismantled" bit !!! On a 'B' this can easily happen if you don't happen to have a magnetic screwdriver. The distributor is not too well placed for easy access ... Mark
1111.18		RDGE44::JONESK	Yep you sure are	`Thu Jun 14 1990 14:41`	6
	last night driving home I took her up to 65-70 and had no problems. Again today I had her going 70-75 and again no problems. Maybe it was a freak bit of gunk in the fuel line? Kris.
1111.19	Float Needle.	TAGART::SOMERVILLE	Flonk your Dwoyl!	`Mon Jun 18 1990 20:16`	3
	Could be. However if it comes back SU carb. float needles are infamous. Robin.