QuestionI have a 76 spitfire 1500 but it has a 78 motor just in case that helps I have 2 questions one is when I try to put car in first or reverse it grinds bad an have to force in all air seems to be out of system but it shifts through the rest of the gears fine and with the brakes I cant get fluid to the rear brakes an I just rebuilt the master cylinder any ideas will be much appreciated and also what are the valves suppose to be adjusted to thank you.
AnswerHi Ryan,
The grinding going from neutral into 1st and reverse is an indication of a dragging clutch. This can be due to the hydraulic system not fully releasing the clutch (air in the system) or it can be caused by other things. Like a warped clutch disk, a pressure plate not releasing squarely or a clutch sticking on the spline of the transmission input shaft or a binding pilot bearing.
Another factor is idle RPM. If the Idle is too high or even incorrect driver operation can cause it. Here are a few tests that are easly to run.
With the car on level ground and the brakes off, warm the engine up and note the idle RPM. It must be between 750 RPM and 900 RPM but not higher. With the engine idling depress the clutch pedal all the way to the floor and put the shift lever into 2nd gear. (should be no gear clash) Now quickly put it into 1st from 2nd. Note if there is any gear clash. (should be no gear clash) Now keep the clutch pedal on the floor and let it idle for a minute or two and don't touch the brakes. Note if the car tries to "Creep" forward any at all. (Should not creep at all)
Now put the shift lever into Neutral and let the clutch out. Now put the clutch pedal all the way on the floor and hold it there for 15 seconds and confirm that the idle is below 900 RPM and then put the shift lever into 1st gear. If there is no gear clsah or it is very slight then you have been using incorrect procedures. If you get gear clash you do have a problem with the car. (any one or more of the problems I noted earlier)
This is a preliminary rough test we used to test the hydraulic clutch system. This is done by hand. Depress the clutch pedal by hand. It should move about an inch free play with no resistance at all except for a minor resistance by a clutch pedal return spring (if it has one). Then drpress the pedal slowly all the way to the floor by hand. The pedal should feel firm as soon as the free play it taken up and as you push the pedal to the floor it should feel just about the same resistance from there all the way down to the floor.
When air is in the system the pedal well feel easy and soft at first and slowly get harder as you get closer to the floor. This is just a preliminary test of the hydraulic system. There are other things that can cause this but they are rare.
Bleeding a clutch is difficult due to the large size of the clutch hydraulic line. One of the sure methods used by some mechanics is called "Reverse Bleeding". Without a pressure bleeder this can be done by removing half of the fluid in the reservoir and leave the cap on but loose. Then remove the slave cylinder from the bell housing leaving the line attached. Then depress the slave cylinder piston all the way into the bore of the slave cylinder to it's bottom. Then reinstall the slave cylinder. Note that the master cylinder reservoir is now about full. Now pump the clutch pedal in smooth full strokes very slowly down and even more slowly back. Do this until you feel pedal pressure and you should arive at a feel as I noted above. Then fill the master cylinder reservoir (using DOT 4 fluid).
If none of this works then you do have an internal clutch problem and you need to remove the transmission to correct it as the problem is internal.
Let me know,
Howard
