(no subject)
Apr. 10th, 2017 09:56 pmI sat down with the Spitfire last night, to try to figure out why it was making weird crunching and grinding noises almost every time I went over any sort of bump, lump, depression, or even when turning hard enough to move the suspension. (Even though it's a gocart it still has a bit of body lean when cornering hard.) The leading thesis going into this was that it was the exhaust pipe touching the ground. That is in fact happening. (This is a consequence of me installing the new engine about 5cm lower, and 5cm further back, than the previous one, to improve the handling. If given the chance, I'm gonna move it back another 10cm at some point.)
But I was pretty sure, from both the sound and from when it happened, that not all the noise was exhaust-on-pavement.
Turns out at some point someone else (presumably) hit the front left corner of the car hard enough to put a dent in the bumper, and also bend the bumper and underlying frame element back a little bit, just far enough that when the body drops slightly, or the tire rises slightly, the outside edge of the tire touches the fender. That's what I'm hearing.
It didn't used to do this because when we got the car it had the original 1975 tires on it, and they're smaller and narrower. When I got the new engine in it, and we were clearly going to drive it a lot more, we got new tires. (35 year old tires are just flat-out unsafe, anyway.) The closest replacements for the original tires have a slightly different shape, width, and height.
So now I have to figure out how to move everything back where it should be.
This is complicated because the bumper bolts into the frame in six places, one outboard of the impact point, so I can't just remove the bumper, straighten it, straighten the frame, and expect them to still fit together: they will bend about different arcs and the outermost bolted joint will no longer line up.
As a result, I get to figure out how to straighten them together.
This isn't specifically why I bought an eight ton jack many years ago, but that'll sure help.
But I was pretty sure, from both the sound and from when it happened, that not all the noise was exhaust-on-pavement.
Turns out at some point someone else (presumably) hit the front left corner of the car hard enough to put a dent in the bumper, and also bend the bumper and underlying frame element back a little bit, just far enough that when the body drops slightly, or the tire rises slightly, the outside edge of the tire touches the fender. That's what I'm hearing.
It didn't used to do this because when we got the car it had the original 1975 tires on it, and they're smaller and narrower. When I got the new engine in it, and we were clearly going to drive it a lot more, we got new tires. (35 year old tires are just flat-out unsafe, anyway.) The closest replacements for the original tires have a slightly different shape, width, and height.
So now I have to figure out how to move everything back where it should be.
This is complicated because the bumper bolts into the frame in six places, one outboard of the impact point, so I can't just remove the bumper, straighten it, straighten the frame, and expect them to still fit together: they will bend about different arcs and the outermost bolted joint will no longer line up.
As a result, I get to figure out how to straighten them together.
This isn't specifically why I bought an eight ton jack many years ago, but that'll sure help.