Your seals may have gone bad. Do a search on the web for "Air Gun Repair" and locate a shop to have it repaired, OR, See the links below.
The Benjamin or Sheridan pump rifle should never be pumped more than 8 times. See the link below for the owners manual (Crosman owns Benjamin and Sheridan air rifles)
Today Crosman air gun company owns both the Benjamin and Sheridan line of air guns. The .22 caliber model 342 was made between 1969 -1992. Crosman offers a free service to locate repair shops that repair older Benjamin, Sheridan and Crosman air guns and rifles. These shops usually have all the parts needed to repair the air guns. The link is on the Crosman home page. See the link below.
Most definitely the answer is YES! If it's really old, Crosman (Who owns both Benjamin and Sheridan) offers a free service to locate independent repair shops around the country that repair older airguns. (See the link below) if it's a newer model, Crosman may have the parts to repair it. (see the #2 link below)
The Blue Book of Airguns has the info you need. Also, all Sheridan Streaks are .20 caliber, not .22 caliber.
The Sheridan Silver Streak is a 20 cal pump air rifle. To get an estimate of value please state the condition of the air rifle. Is it working? Is it in poor, fair, good, very good, or excellent condition.
you may find that the repair may cost more than the value of the rifle. But you can search the web for "air gun repair" and locate a shop near you to have it repaired or contact customer service at ( Daisy.com ) and ask them.
Where do I buy Benjamin Air rifle repair parts? Model 310 and 310
you don't unless you are a skilled mech
I use a Mistubishi electric fuel pump and it works good.
what government agency will give me a grant to repair my heat pump
You cannot repair the water pump. It needs to be replaced.
Yes you can replace the seals or worn parts. OR, Crosman air gun owns Benjamin. Crosman offers a free service to locate shops who repair old rifles. See the link below.