After sorting most things on Saturday, I decided that Sunday was the big day. The Cadillac and LaSalle club were meeting at the Scoresby Picnic, so I decided to go along. It was a nice autumn day and not too cool. I got out of bead early (6:30am) so I had time to wash it and clean the tyres. I cleaned the tyres using some Jif creme cleanser and a scourer. The grunge was easily removed, and once had given the tyres a coat of tyre shine they came up sweet.
The rest of the car came up pretty well also
When we arrived at the picnic, they had a special section reserved for Cadillacs & LaSalles which was nice. I was in good company, and the car attracted plenty of interest which was nice. I can’t wait to polish the stainless and the paint.
I then drove it home again. although it is running OK and seems to have plenty of go, there is a slight miss most of the time. It is not right so I decided to investigate a little. If I can sort this out I might be able to reduce the idle speed which would be a bonus.
Reading the Plugs
I pulled out the plugs to check what they looked like. From what I can gather from the spark plug manufacturers sites, the timing is pretty well right, however they look a little lean. Keeping in mind that it was running rich to start with, and it has only done 75 miles I didn’t want to get too excited. What was more important was that all of the plugs looked very similar.
After some more pondering, I decided that there are a couple of things I am going to do. First I will remove the shims from the heat riser so the manifold gets hot enough to vaporize the fuel. I can’t help but wonder if poor fuel atomization is contributing to the slight miss. I am also going to check for vacuum leaks, check the inlet manifold is sealing and will also measure the valve travel to make sure I don’t have a dodgy lifter or cam lobe.
Tonight (Tuesday) I removed the inlet manifold. There were no visible signs of leakage around the ports which is good.
I measured the inlet manifold gaskets to see how big the angle mismatch is between the heads and the manifold. The results were as follows (measurements in mm):
It is not as bad as I thought, and I will be able to correct it a little by hand and then reinstall it. I know as soon as I open up the heat riser passage the paint will get burnt off of the centre runner so I am planning on painting it with the KBS XTC exhaust coating so it doesn’t peel off.
Next job will be checking the valve travel.