Bob’s Restoration – Checking the Carbs

Bob’s Restoration – Checking the Carbs

Bob’s Restoration - Checking the CarbsMy hunch is that this engine will run. So, for my long range plannnng purposes, I am going to do the rudimentary work that needs to be done to see if I can get it to jump to life.

I don’t need it to purr – just to rumble and growl at this point. So I wanted to go through the carbs and see what was going on there. I took the carbs off and the carbs looked remarkably clean inside, although it was a real make shift job on the accelerator return spring set up. This spring set up was the first really poor fix I have found on the car.

So after I took the carbs out and was nosing around this is what I noticed….the nut on the stud of the broken flange came off with no issues and I didn’t have to torque on it at all. It’s been a while since I worked on these cars and I can’t really see a clear cause why both of these parts would be broken. I also notice the last exhaust manifold stud closest to the scuttle was also broken.

Bob’s Restoration - Checking the Carbs

Bob’s Restoration - Checking the Carbs

Bob’s Restoration - Checking the Carbs

Any ideas what would cause these two pieces to break like this? Is it from two separate issues or the same one? Maybe some one with a prybar trying to loosen the exhaust manifold for some reason? Any thoughts?

Additional Comment from a Reader:
“Probably caused by over tightening the nuts. You do know these are not from an MGA, don’t you? Looks like an MGB set up, including the heat shield and inlet manifold. I’d have a quick peek to see if you’ve got an 1800 engine in there as well. Might explain the Heath Robinson throttle return set up.”

Comment from the Author:
“It’s definitely a 1500 engine, and no I didn’t know it was an MGB set up. From memory of 20 years ago, it looked like my previous MGA’s carb set up so I never gave it much thought, which incidentally as I think about it, was a 5 main bearing MGB 1800. I have one of the carbs soaking now in carb cleaner. Both carbs had the ID tab still on it, so tonight I will pull it out and clean it up and put the other one in to soak. My guess is the carb ID tag from the float will tell me something about them. I am still in the re-learning curve big time with this car. It’s all faintly familiar and the more I look at it the more I remember about the last one. Luckily I have all the repair manuals for both the MGA and MGB, so I have reference manuals to guide me. Is the Heath Robinson throttle return set up an improvement over the original design?”

Additional Information from a Reader:
The H4 carbs on the MGA have the bolts straight up and down, while the HS4 MGB carbs have them canted diagonally like that. Nothing wrong with running the MGB carbs – the flexible jets are, if anything, less likely to leak past the glands in the jets than the MGA carbs, although with currently available improved gland seals (around the jet) for the MGA that isn’t as much of an issue as dried out cork seals used to be. Don’t hesitate to go with what you have if you can’t lay hands on inexpensive MGA carbs and manifold, although obviously you’ll need a new MGB manifold – should be cheap from all the fools that fitted downdraft Webers and chucked the “good” carbs!”