[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
Wastegate Springs (and broken WG hoses)
I took the WG apart on the qtc this weekend to compare the new spring to
the old one. While I was at it I decided to disassemble the WG on the
5kT for comparison. I found Charlie Smith's new spring to be very similar
to the one I had in the car, and both were much stronger than the one in
the 5kT. I believe that I got one of the first series of springs from
The spring that I pulled out of the qtc was almost 5 turns of 0.140" wire,
with what I would estimate to be 3 turns not counting the flat parts for the
seats. Measured at the approximate center of the wire, the length of the
spring is 2 11/16" with the seating surfaces 2.75" apart. The spring had
two black dots painted on each coil of the spring.
The spring I got from Cahrlie Smith has 6 turns of 0.150" wire, with a
height of 2.5" to the center of the wire and 2 5/8" seat to seat.
I did a semi-scientific test on them since they were about the same height
I put one spring at each end of a bubble level and pressed down in the
center. The level stayed pretty much centered as I compressed the springs,
which would indicate that the force constants were about the same.
I didn't take detailed measurements on the spring I took out of the '88 5kT
wagon, but the spring was about 2" tall and had a much lower force constant.
The spring perch appears to be much higher on the 5k, so the spring will be
One thing that I noticed when I took apart the WG on the 5k was that the
hose that supplies pressure to the top of the WG diaphragm was leaking.
For some reason there is a larger diameter hose that is placed over the
hose that goes from the valve to the WG. I think the larger hose got hard-
ened over time and placed a lot of stress on the smaller hose at the WG
connection. I replaced the hose from the valve to the WG and noticed that
I was seeing 1.3 bar on the display much more frequently than I had in the
past. Who knows how long the thing was leaking ....
San Jose, CA (USA)