QuestionQUESTION: Hi!
I have a 1965 mgb. I just changed the mastercylinder for the clutch and now I hear a metallic rattle when I press the pedal fully to the floor, The sound is only there when I press it the last inch. Do you have any idea what courses the sound and how I fix it?
It has been changed to 12 volt -I've been wondering if I can put in a second 12 volt battery?
Best regards
Miller
ANSWER: Hi Miller,
The MG has a carbon type clutch release bearing and that may be worn all or most of the way down. Or the metal pad on the pressure plate may have a problem. Either way you have to remove the engine to gain access to the clutch.
If it were mine, I would do it soon as it could be serious and cause a lot of damage. It is not as big a job as it sounds. When I was working in MG dealerships in the mid 60s I was timed at removing a MGB engine and I was able to put an engine out and on the floor in 35 minutes. Some mechanics we had could even beat that time. A few years ago I pulled one using the same tools I had then and it took me 3 hours. So age has something to do with the time.
The book time is 7 hours to remove and replace the engine unit with extra time to replace any parts like the clutch and release bearing. If you do the job yourself, you should replace the clutch disk, pressure plate and release bearing. Also check the amount of ware on the pilot bearing and look for oil leaks from the input shaft of the transmission. It pays in the long run to do everything you can while in there.
Some mechanics remove the engine and transmission as a unit and others just the engine. I have done them both ways and each has advantages and disadvantages. If you have not done a lot of this kind of work I would advise that you take both out as a unit mainly because it takes some skill to engage the transmission shaft into the clutch when installing the engine and many were brought to me after someone damaged a new clutch try to put an engine in.
Howard
The MGB was always 12 volts but just had two 6 volt batteries in series which is 12 volts. If you have a 12 volt battery in the car now, there is no need for a second battery.
Howard
---------- FOLLOW-UP ----------
QUESTION: Hi Howard!
Thanks a lot for your answer.
I've pulled the engine twice -4 years ago to change the clutch and this winter to do a complete gearbox restoration. So I am familiar with the procedure :-) -However it's not a job you are eager to do!
You say you would do it as soon as possible -What's your opinion about letting it role for another approx. 1000 miles and do the job this winter when it's locked up in the garage anyway? What kind of damage are we talking about?
The reason I asked about a second battery is that I have two which are both "over the hill" and I would prefer to wait and buy a new one till next spring -that way the new battery wouldn't stay unused all winter "loosing lifetime". So, is it possible, and if -would it give that little extra power to start the engine?
Have a nice weekend.
Best regards
Miller
AnswerI worked in MG dealerships for most of the life span of the MGB and clutch release bearing jobs were common and I would do as many as 5 to 10 a week for many years and some were driven with the carbon completely worn down and the metal of the release bearing was eating into the metal pad of the pressure plate. The problem is that when the carbon is gone the release arm moves in an arch and that makes the load on the pressure plate pad not in the center any more. This starts making a lot of metallic noises and soon breaks the pad loose from the pressure plate and that causes a lot of damage when tangling with the clutch release arm (fork).
That does not mean that is going to happen to yours. You just need to know what can happen. I have pulled clutches out that were making noise and it was just the pad on the pressure plate was loose as some are only held in place by a large clip pressed on. There is no way that myself or the man who designed the car can tell you how long a noise is going to make you clutch last. I have always owned MGBs and I would not drive mine very far with clutch noises.
As for the batteries, you can run two 12volt batteries connected in parallel just as some diesel vehicles do. The only trouble is if one is worse then the other it probably has a different internal resistance and the charging system will put all the charge into one battery more then the other. If you do it, just watch the water level in both batteries closely as one will start requiring water more often then the other.
Howard
