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Picking up my first MGB today!

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Aetticus Bradley Doern
Sacramento, CA, USA   USA
So I've decided to chase the rabbit down a hole; I bought my first MG, a 1980 'B, for three reasons...

I was looking for a small car that would get me to and from Portland, OR reliably; previous owner drove is cross country three years ago,
It was a convertible, and I'm new to California; never had a convertable because I lived where it rains 90% of the year,
And, the best reason, the thing looked like it was fun to drive.

I couldnt drive it home because the clutch master cyl was bad. Starts and runs though; I'm literally 20 minutes away from driving it home!

So the tech questions...

I'm replacing the clutch master and slave units; whats the best way to go about this? I'm assuming that the lower clutch master has to be accessed from under the dash?

Should I use dot 3 or 4? I'm down with using 5, but dont know if its necessary. I love to drive, so a firmer clutch pedal would be worth the extra cost.

Is there a restrictor I can take out in the line somewhere? I had a car that when I removed it, it was like night and day.

And finally, is the car put together with metric nuts and bolts? So far I think I've found all metric, but I want to be sure.

I'm really excited to learn and own a new car that is foreign to me. I've done muscle cars and JDM imports, but never Euro. Most of my MGB searched end up in this forum anyway. If I ask a question, I either cant find what I want specifically, or I want to generate a discussion about the topic. I love to learn my cars thoroughly, and maybe my question will teach me something more than the answer!

Thank you for the replies in advance!

Brad "Aetticus" Doern
1980 MGB, currently unmolested

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Steven 67GT Avatar
Steven 67GT Steven Rechter
Imperial Beach, CA, USA   USA
Congratulations on your "new" car.

The first thing you really need to be concerned with is if you a going to register it in Cal and if so getting it to pass Cal smog.

BTW Dot 3 or 4 but not 5.

sger Avatar
sger Silver Member Stuart Greenblatt
Evanston, IL, USA   USA
1973 MG MGB
Brad -- Congrats on your new B! You'll learn much on this Forum as the members are generally very responsive.

I'd also recommend that you use the "search" function to research questions you might have. It's along the top under the header bar. It's incredibly helpful.

Edited 1 time(s). Last edit at 2017-09-12 10:34 AM by sger.

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Aetticus Bradley Doern
Sacramento, CA, USA   USA
@Steve - No big issue was smog, I have family with a full on speed shop in Lake County, and the car will be living there. If that doesnt work, I am an Oregon resident, and haven't fully committed to living down here... Staying with my Aunt and trying out the Cali life. If I land a good job, I will take residency in CA, but for now just doing work for her; she inherited her mothers home and it needs quite a bit of work.

Thanks for the reply on the fluid! Does an SS clutch hose make a good difference? And is there supposed to be a stop at the top of the clutch pedal? My cousin let it slip when bleeding and it yanked the rod out of the master!

Edited 1 time(s). Last edit at 2017-09-12 10:37 AM by Aetticus.

tomkatb Avatar
tomkatb Larry Baygents
Dayton, Ohio, USA   USA
1963 MG MGB
Clutch master, slave and hose is a fairly easy replacement. If you have the right tools. The master is under the hood. You reach thru a hole in the firewall for one connection. The slave is near the starter motor. If you have done this before it is a 2-3 hour job. For you I would guess a lot more. Lots of tricks. Look at old posts.

A MG has no metric fasteners. Owners do do odd things. The car has NO phillips screws. They are Posi, not the same. Six point sockets and flare nut wrenches are used to take stuff apart.

There are a few Whitworth fasteners. We use an adjustable wrench if needed. (original hose to the oil cooler, original hose to the calipers)

Your car shipped with Girling or Castrol LMA brake fluid. 3/4 dot. Dot 5 will give you a softer pedal by 10-20%. Study by the US Army. Keep things simple for now.

As you live in CA I do not think removing a restrictor, whatever that is, is legal. Your car must be bone stock for inspection as i remember.

Have fun. Tow the car home. It can be driven this way but, it requires practice, finesse, luck and should be done when there is no other traffic. I would not do it very far.

77 Spit

lbcnut Avatar
lbcnut James Woolf
Grass Valley, CA, USA   USA
1964 MG MGB
Hey Brad, this is James, the guy you bought that POS off of! Don't hesitate to give me a call if you have any questions...

Cruisedon66 Avatar
Cruisedon66 Pete W
St. Louis, MO, USA   USA
1976 MG MGB
Congratulations Bradley!
Dot 3 or 4.
I think someone has done a conversion to a different sized slave cylinder. That might help with the feel you're looking for if the stock motion still doesn't feel right to you.

MG's are all SAE sized except the inside of the engine.

Tip: If the carburetors have a cap on top that unscrews; Check to see the oil level is about a half inch from the top. 20/50 Motor oil.
see Attachment for what they look like.

Tip: The transmission takes engine oil- 20/50.

MG's could be ordered with an electric overdrive transmission. The best way to tell if you have it is to look at the tailshaft on the transmission itself.

The rear brake shoes are not self adjusting. You'll need to periodically adjust them.

Lots of good tips here; John Twist MG Guru

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Steven 67GT Avatar
Steven 67GT Steven Rechter
Imperial Beach, CA, USA   USA
In reply to # 3590703 by lbcnut Hey Brad, this is James, the guy you bought that POS off of!

They always return to the scene of the crime smiling smiley

Nicecar Avatar
Nicecar Gary (ex "Harv") G
Victoria, BC, Canada   CAN
1980 MG MGB "Red On Red On Red"


I've owned my /80 for 24 years. I LOVE it, and after untold hours of labour of love, and more than a few scheckles, now everything works! I really enjoy hearing from folks who also own this last year of production.

You'll get much advice, but I may be the first to tell you is that, as I spend about two hours each day (too much) on forum, over the years I heard MANY stories of huge frustration by many who have trouble with what should be the simple process of bleeding. Many have spent many hours.

After hearing so many horror stories, I took mine to an MG mechanic and he installed mine (me there to assist in bleed) at 1 hour labour cost. No stress for me, the best money I ever paid a mechanic.

If you can get clutch working 100% - great, if not above to resolve issues. I was able to drive mine the 20 miles to mechanic.

It would be a shame for you to begin your life with this lovely beast on what should be simple turning into hours of frustration - that might (will?) come later.

I purchased my non-Chinese (turns out it was British, but I only insisted "non-Chinese"winking smiley from Basil Adams (707) 762-0974 (Ca.); clutch slave and hose. He can get you parts fast - call him, he's in Ca. too.

After posting you have one week to edit. Years ago I proposed (if able in that week) to add "SOLVED" to your first title.

Best wishes; keep us posted, looking forward to "SOLVED".

How many miles?
Points or electronic?
If not too indiscreet how much?

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Discocontented Avatar
Discocontented Erik Walter
MN, Crystal, USA   USA
1978 MG MGB "Vivian"
I agree on the tow, honestly, but you might try pumping the clutch pedal to build up pressure and shift. I got home from work one time doing just that. Maybe try late at night when traffic is light ; )

Will 1965 William Murphy
Coolafancy, Wicklow, Ireland   IRL
1965 MG MGB MkI "EZI"
Congratulations. As some of the other lads have suggested. Check your clutch fluid level , top up if required and pump the pedal to see if u can get enough travel to get home.
I did same job on my 1965 recently and no big deal but you are better off not
rushing the job if it's your first. Also , handier if front end securely on axle stands. Up under the dash on drivers side is a blanking grommet that pops out to give u access to back of master cylinder. Also , pipes may be literally welded on fittings so if a pipe won't budge, just stop have a cuppa and try again. As your changing the slave you might as well fit a new hose. Standard are fine. Clutch will be smooth in operation and quite light. Don't spill brake fluid as it will happily strip paint. Bleeding is easy . You need an assistant to pump pedal and hold down when you open bleeder. Come back to us when you're that far. Sorry if all this very obvious to you.
Budget for new tools as no metric on a MGB !

Ex-Calif Avatar
Ex-Calif Gold Member Dan D
Cincinnati, OH, USA   USA
1968 MG MGB GT "Bart - Yellow And Naughty"
1977 MG MGB "Red Betty"
2012 Jeep Liberty "Tank"
2014 Hyundai Accent "Skate"
You will find a selection of SAE and some Whitworth but I am not aware of any metric?

Dot 3/4 is fine.

There is a pedal box cover on the engine bay side and there are mounting bolts on the firewall that need to be accessed from under the dash. Many will tell you no need but I pull the drivers seat out any time I work under the dash - 10 minute job.

No restrictor as far as i know.

Also order the flexible clutch hose from the car bracket to the slave. Be very careful breaking the hose loose or you can break the hard line - I believe the upper nut is a whitworth.

Congrats on the car. If you a re gonna make it a daily driver be prepared to work a lot of reliability issues and then enjoy miles and miles of trouble free driving. I just finished 1800 miles in my roadster in July and 1500 miles in my GT in August.

The goal - Reliable summer driver interspersed with mechanical tinkering...
Motto - "Driving fifty in the twisties..."
On Mods - It's your damn car - Do what you want. Haters gonna hate...
On SUVs - Drive your B like a soccer mom is texting her friends about how she wants to kill you...
Red Betty -
Bart -

lorwood Avatar
lorwood Ed S
Ridge, NY, USA   USA
1979 MG MGB
Congrats. They are a blast to drive!!!!!! Those that drive these "go carts" on a daily commute or for long trips are a lot braver than me.

"He rides 'er low on the hip, on the side he's got "Bound for Glory" in red, white and blue flash paint
He leans on the hood telling racing stories, the kids call him Jimmy the Saint".."And I said, "Hey kid, you think that's oil? Man, that ain't oil, that's blood"
I wonder what he was thinking when he hit that storm, or was he just lost in the flood?"

angliagt Avatar
angliagt Doug Milota
Roanoke, VA, USA   USA
1967 MG MGB GT "The MG"
1974 MG Midget MkIII "The Midget"

When I saw the picture of where he bought it,I thought -
"That looks familiar".I was right.


Welcome - I know James will treat you right!

Aetticus Bradley Doern
Sacramento, CA, USA   USA
Ha! Hey James!

And first up, THANK YOU to everyone that has replied! I'm actually kinda overwhelmed at how many have read and responded! This is going to make MGB ownership even better! Let me know if I didnt touch on your question and I'll def address it lol.

I dont mean to sound cocky, but I am a fairly experienced mechanic, and have been turning a wrench since I could pick one up. Replaced the clutch master and slave in 30 minutes. Super easy, and thank you for the tip about going under the dash; I would have figured it out eventually, but def saved me the time to figure it out on my own!

...I plan on doing everything myself, including the inevitable Buick/land rover alu block 215 (3.5L) v8 swap!

@Larry - Used dot3/4 fluid, thank you for the info on the dot 5 feeling weak. I would have assumed the opposite!

I got the clutch bled out for the most part, but I still have to pump it to get full clutch disengagement. Might need a bleeder pump, or just to bleed it out again. My helper mighta let the res go dry.

Got the thing running and driving, and did 80mph the entire way home. What a blast! 20 miles with ZERO problems! I was amazed! She ran nice and cool too. Pressure washed outside and under the hood; unfortunately some of the paint came off lol. Oh well, guess I'll have to paint it eventually!

Having issues with idle, but after poking around under the hood, Im pretty sure its a combination of carb tune and vacuum leak. I'll ask in another post if I cant find it, but it's been converted to twin SU carbs, and I need info on vacuum hose plumbing, specifically the PCV system.

And thank you for the info on the carb oil level! Still no idea what THAT does lol. I'll have to do my research. Also good info on the trans fluid, and the read brake adjustment. No auto adj seems silly, more of a reason to go to dick rears I guess. winking smiley

Oh, as far as the 'restrictor' I was referring to, that was in the clutch hydraulic line, its not a performance thing. Basically lets the fluid out of the slave slower, smoothing out your shifting, and preventing shocking the running gear.

@Gary G
Supposedly the car has 67k original, and honestly she drives like it. Very tight.
Dont know about the OD, but she does have a 4 speed manual. Pretty sure not; the only thing I could find near the tail shaft was what I assume is the speedo cable.
Carb has been converted to twin SU.
Ignition has been converted to points.
The clist posting was for $800. I'll let James tell you if he wants to let that information out. winking smiley

Thank you again for the warm welcome, and I'm really looking forward to this car. Its been a few years since I got a car I was this excited about!

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