Motor help

[turtleescape]

I need help with my pump motor. It works fine on low. When I try to switch it to high it just jerks in and out like it is trying to start but can not. I pulled the cover off the back of the motor and I can not find a start capacitor. The motors model number are not legible anymore. From what I can find it is a Jacuzzi pump with a Magnetek motor. The motor is rated at 8.8/2.6 amp but I can not find much else on it. Anyone have any ideas? Thanks for any help.

[Poconos]

Welcome to the forum.
Couple questions. Is this something new? That is, was it working fine on high speed and something failed or changed? When you say it jerks in and out do you mean it spins, comes up to speed then dies and keeps doing this cycle?
There has to be a starting cap in there somewhere. Reason I'm asking the questions is that a motor that's wired for 240 will run on 120, but can't handle a load. What happens is on the starting winding there is enough torque to get it going, but once the starting winding kicks out it slows up and the starting winding kicks in again, and keeps repeating this cycle. Never dealt with a two speed so it could probably be something related to the windings.
Al