mgs
[Top] [All Lists]

Re: [Mgs] Performace queery

To: "mgs" <mgs@autox.team.net>
Subject: Re: [Mgs] Performace queery
From: "Bob Donahue" <bobmgtd@comcast.net>
Date: Thu, 29 May 2008 20:52:30 -0400
I had a clogged fuel line to the front carb that acted some what like that. 
The symptom only appeared under high throttle demand (like going up a hill). 
Under high throttle, the partially blocked carb would run out of fuel. There 
was enough fuel getting past the clog for regular cruising. The way I found 
the problem was pushing the float pins down. The tick-tick sound of the fuel 
pump was much slower on the clogged carb.

Bob Donahue (Still Stuck in the '50s)
Email - bobmgtd@comcast.net
Cars:       52 MGTD - #17639
               71 MGB - #GHN5UB254361
Member:  NEMGTR #11470
               NAMGBR # 7-3336
               Hoosier MGB Club
               Olde Octagons of Indiana

----- Original Message ----- 
From: "The Roxter" <rocknatural@gmail.com>
To: "Richard Ewald" <richard.ewald@gmail.com>
Cc: <mgs@autox.team.net>
Sent: Thursday, May 29, 2008 1:43 PM
Subject: Re: [Mgs] Performace queery


> Richard Ewald wrote:
>> A problem such as this can be caused by several things.  Paul
>> mentioned misfire and high voltage break down.  This is a strong
>> possibility.  Your B probably needs about 10-12K volts to fire the
>> plug at idle.  Open the throttle and it might take up to 20K volts.
>> If your car's plug wires start firing to ground at 15K volts it will
>> run fine at idle, and low throttle openings.  A large throttle opening
>> will cause the engine to misfire and no acceleration.
>> A low output from the coil could also cause this.  If there is not
>> enough voltage going into the coil due to poor connections this could
>> show up.  It could be a bad coil, but honestly, these are real rare.
>> Coils almost never go bad.
>> These are just some of the reasons that back in the day tune up shops
>> had O-scopes in them.  About 30 seconds on a scope and I could nail
>> the problem.
>> I very seriously doubt it is a vacuum leak.  As a percentage of total
>> air going into the engine a vacuum leak is greatest at idle.  A vacuum
>> leak having an effect at 3500 RPM would require a huge leak, and I
>> doubt the engine would idle.
>> Stuck carb pistons could cause such an issue, but I would look at the
>> electrical stuff first.
> Another possibility would be a clogged fuel filter or weak fuel pump.
>
> -The Roxter
> --
> _______________________________________________
> Support Team.Net  http://www.team.net/donate.html
>
>
> You are subscribed as bobmgtd@comcast.net
>
>
> Mgs@autox.team.net
> http://autox.team.net/mailman/listinfo/mgs
>
> http://www.team.net/archive
_______________________________________________
Support Team.Net  http://www.team.net/donate.html




Mgs@autox.team.net
http://autox.team.net/mailman/listinfo/mgs

http://www.team.net/archive

<Prev in Thread] Current Thread [Next in Thread>