New MGB GT

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crapday69
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Re: New MGB GT

Unread post by crapday69 »

I had to go shopping today. I could have took the C5, drove with the windows shut and aircon on, sitting in comfort without a care in the world. BUT I choose to take the MGB, windows down car roaring along and me looking at the smiles on peoples faces as I drive past. But the biggest smile was on my face.

Gary.

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Skull
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Re: New MGB GT

Unread post by Skull »

Sounds like a bargain Gary hope you enjoy many a mile your dream car ..... =D>

Hell Razor5543
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Re: New MGB GT

Unread post by Hell Razor5543 »

I bet you were in danger of losing the top of your head with that grin!

crapday69
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Re: New MGB GT

Unread post by crapday69 »

once this pandemic is over and we return to, well lets say as normal as we can ever be now, i'll post pictures of all the fun runs we go on.

crapday69
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Re: New MGB GT

Unread post by crapday69 »

it's gonna cost me £69 to insure my son for a week. Its the least I can do as he'll be doing the carbs lol.I didn't realise how excited hed get when I got the car, he loves it as much as me.

He should have qualified as a mechanic but as he's been furloughed it'll be January now. He'll be learning new stuff working on the MG that he never learned in collage or the workshop (carbs for a start) but I did notice how good he is a looking at diagrams and schematics.

Hell Razor5543
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Re: New MGB GT

Unread post by Hell Razor5543 »

crapday69 wrote:
31 May 2020, 00:25
it's gonna cost me £69 to insure my son for a week. Its the least I can do as he'll be doing the carbs lol.I didn't realise how excited hed get when I got the car, he loves it as much as me.

He should have qualified as a mechanic but as he's been furloughed it'll be January now. He'll be learning new stuff working on the MG that he never learned in collage or the workshop (carbs for a start) but I did notice how good he is a looking at diagrams and schematics.
Looking is easy; it is the understanding that is difficult.

Peter.N.
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Re: New MGB GT

Unread post by Peter.N. »

I'm sure many of the mechanics of anything like my age learn't on the job, there's nothing like experience, being able to set up twin carbs by listening to them and adjusting the ignition timing by ear and feel. I have always repaired my own cars since my first one in 1956 and still do - at the moment.

I was a TV engineer for 50 years but had no qualifications whatsoever - except perhaps my RAE although that was much later. There was such a shortage of TV engineers back then and probably right up to the '90s that if you could repair the sets you could get a job - I could and I did. I suspect many motor mechanics did the same.

Peter

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Paul-R
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Re: New MGB GT

Unread post by Paul-R »

Peter.N. wrote:
31 May 2020, 09:20
... being able to set up twin carbs by listening to them ...
Not as easy as it sounds (ho ho), I used to find that on some cars the quality of the noise was different making it difficult to set them up for equal sound volume. I tried a Gunsons Carbalancer but I don't remember having much success with that either.

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white exec
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Re: New MGB GT

Unread post by white exec »

From memory, there were two main adjustments needed for twin SU's: air-flow and mixture, and a small one for throttle synchronisation.
Twin SU's.jpg
Setting mixture was the same as for a single carb. With engine warmed up and at idle (and the dashpot properly filled - not engine oil, please, Haynes!), the piston needed lifting by about 1mm, using the little lifting pin in the carb base. You listened to what happened to engine revs. If the revs rose, and stayed there, the mixture was too rich. If revs fell when the piston was lifted, the mixture was too weak. The mixture was correct when revs rose for 2-3 secs, then fell back again. The mixture was easily adjusted with the large jet nut at the base: screw out to enrich, in to weaken. Simples, infallible. For twin or more carbs, you just did this for each.

For air-flow, the aim was to get the flow of air through each carb equal. This could be done with a simple length of plastic tubing, used as a stethoscope. With one end near your ear, the other end was positioned (engine idling) against the intake flange of one of the carbs, and you listened to the hiss. This was then transferred to the other carb, in the same position, and the hiss compared. The louder the hiss, the greater the air-flow, and the aim was to get both of them the same. This was done by adjusting the idle speed screws on the carbs, which set the opening of the butterflies at idle. This was done while keeping an eye on correct idling speed.

More accurate than listening to airflow, was monitoring it with a carb balancer, which allowed air-flow to be read off visually on a scale. The Gunson's Carbalancer used a plastic venturi scale, which contained a little plastic float that hovered in the air flow. You pressed the unit's shallow cone to one carb intake, and set the shutter on the cone to put the little float roughly half-way up the scale. Transferring the cone to the other (or next) carb allowed the air-flows to be compared. Again, adjustable on the idle screws.

IIRC, it was recommended (on twin carb set-ups) that one throttle butterfly opened minutely before the other, when the throttle was opened above idling. This tiny headstart for one carb was obtained by adjusting the linking shaft between the two carbs, and tweaking the gap in a forked link.
____________

Do remember, with some dismay, having to deal with the twin Strombergs on our Dolomite 1850. One of Triumph's specialities was uneven idling, and this wasn't helped by the two Stromberg carbs drooping somewhat on the end of rubber mounts (rather than being solidly bolted to the intake manifold, normal for SU's). A top-side spring attempted to counter gravity, acting on both the carbs and the substantial air cleaner. What an arrangement! Later discovered that lumpy idling was also a characteristic of the monopoint injected TR6, when I tried to tackle it with a friend's purple lovely. The Dolomite was huge fun, but the list of things that Triumph got wrong was pretty lengthy.

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Skull
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Re: New MGB GT

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white exec wrote:
31 May 2020, 11:36

when I tried to tackle it with a friend's purple lovely. :?: The Dolomite was huge fun, but the list of things that Triumph got wrong was pretty lengthy.
Chris I followed most of what you said but not sure what you mean there - sounds dodgy :lol:

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Skull
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Re: New MGB GT

Unread post by Skull »

Skull’s carb balancer
Skull’s carb balancer
Can’t remember the last time I needed this carb balancer :roll:

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white exec
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Re: New MGB GT

Unread post by white exec »

The 'purple lovely' was my friend's Triumph TR6, a splendid shade of purple-burgundy.
At idle, it just sounded over-rich lumpy (and that's saying something for a Six), but as soon as the throttle was opened, it just purred. Jaguar or Rover would have been ashamed to let something like that get out!

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Paul-R
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Re: New MGB GT

Unread post by Paul-R »

Skull wrote:
31 May 2020, 21:24
white exec wrote:
31 May 2020, 11:36
The Dolomite was huge fun, but the list of things that Triumph got wrong was pretty lengthy.
Chris I followed most of what you said but not sure what you mean there - sounds dodgy
A friend of mine had a Dolomite Sprint and was plagued by a rattle from the back of the car. Eventually he traced it to inside the petrol tank and when he took it off and cut it open he found a loose baffle.

He was so annoyed about it he wanted revenge. At the time he worked for the CEGB (Central Electricity Generating Board) and was based in the Wylfa nuclear power station in Anglesey. He dropped the bit of metal into the reactor pile in the hope that because of the radioactivity the offending item would not be seen again. Now, of course, Wylfa has been decommissioned so I wonder if it has come to light?

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NewcastleFalcon
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Re: New MGB GT

Unread post by NewcastleFalcon »

Bit of MG photography. Spot the roadster.

Got the camera out a bit late I'm afraid. I was on my Bike and I could see the couple in the lovely roadster pootling in my direction. Behind me I heard the unmistakable noise of someone reving the nuts off something so I literally got off the bike and pulled it up on the verge. Two cars passing side by side when one of them cant stop is hard enough on that stretch of road without one of them also taking the racing line at corners. Turns out it was another MG but the newer ones MGF or whatever, which never seem to find much favour at the car auctions.

Anyway by the time the camera was retrieved from the pocket, switched on and ready to go, the rather nice open top classic had almost disapppeared.
Spot the MG Roadster-Can you make out the colour?
Spot the MG Roadster-Can you make out the colour?
REgards Neil

Hell Razor5543
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Re: New MGB GT

Unread post by Hell Razor5543 »

Nicotine stain?