Congradulations. I had a similar problem on my 75 and changed the plugs, but they had been in the car about 15 years and knew they needed to be changed even though they had 5000 or so miles on them. What a difference those plugs make. Now all I need is another new compressor and I can come to Alabama. -----Original Message----- From: mailing-list-owner@xxxxxxxxxxxxxxxx [mailto:mailing-list-owner@xxxxxxxxxxxxxxxx]On Behalf Of KerryPinkerton Sent: Wednesday, March 20, 2002 11:16 AM To: IML Subject: IML: Kerry's vacuum leak - NOT! Ah well better lucky than good. Problem solved but it was a very unexpected solution. A little recap. About a year ago my 73 with a factory rebuilt thermoquad started running crappy. She would cough off idle and was very flat at top end. Vacuum readings were low, in the 17 range when a few months earlier it had been 20. None of the traditional vacuum leak tests show any results including Dick B's trick of covering the primary with cardboard and seeing if the rpm increased before it died. I set the timing and tune over and over and there was no significant change. Last week I replaced a drivers side exhaust manifold (forearm is STILL sore from banging it on the brake booster repeatedly). In the process of doing this I noticed that the plugs were heavily sooted but my spark indicator showed that all were firing strong. Checked the firing order again and again. Based on the lack of vacuum leak test results, i had about decided it was the carb and, in fact, pulled an Edelbrock from my son's Mustang to try a different carb. Of course the linkage was not the same and before I messed with rigging something up I decided to change the plugs. No rational reason for this after all they were 'new'. The old plugs (AC) are about 2 years old but 'new' in that they only have 3-4K miles on them. It was just a cheap, eliminate a slight possibility kind of thing. Autozone only had Bosch and I got the cheap ones since I was just testing. BANG! What a difference! Vacuum back up to 20. Idle is smooth, power is strong. She be back! There is a moral to this story but I'm not quite sure what it is yet. Reminds of my English Lit classes. Didn't really enjoy the process and never quite came up with the same conclusions as the professor... The only complaint is that in passing gear at WOT she seems to stay in passing gear a little TOO long. I say this because the rate of acceleration falls off and then picks back up when she shifts into high. The shift point from 2-3 seems to be about 70 at WOT. If I punch it at 65 she sometimes will drop into second for just a second and then back to high. That however is a completly different problem and I will research it later. For now, I'm going to change clothes and go for a drive in the rain. The 64 is in the shop drying off. She has a squeek in the front end. In the tlc department, the 73 also had a squeek in the rear end and I tracked it down to the upper shock bolt being just a tad loose. Tightened it up and no more squeek. I am a MUCh happier camper. Now I just need to think about what she was telling me and why it took me so long to fall into the solution. Is there a way to tell that the plugs are misfiring under load? Someone asked how to change plugs on a 71. On the 73 (similar) the 1,3,5 4, plugs can be reached from the top. The #7 plug from below and I had to put a wrench on the end of my plug socket as there was no room for the ratchet. #8 also is easier to come out from below. Having said that, there is below and then there is below. Being on a creeper makes for a different arm angle than standing up with the car on a lift. One final trick is because some of the areas are so tight it is difficult to start the plug back in the hole. You can take a piece of vacuum hose or (my preference) a piece of 1/8 id flexible water line and put that over the end of the plug to act as an extender. For several of the plugs this is the only way I have found to get them started. happy happy.. Kerry __________________________________________________ Do You Yahoo!? Yahoo! Sports - live college hoops coverage http://sports.yahoo.com/