Magnum Venus Plastech Turbo Autosprue -TAS - Manual (Page 5)

Turbo Autosprue Instructions Issue_ 11 17/12/08 Magnum Venus Plastech Ltd - Reg No 3978164 Page 5 of 6
Problem Solving:
TAS valve sticking
1. The heavy, and very sticky silicon grease (especially at low temperatures) that is used to lubricate
the air cylinder can if applied too liberally, form a seal between the base of the cylinder and the
underside of the piston. During times of rest the grease can form a perfect, but unwanted seal as
it is compressed by the spring.
o To solve the problem, remove all traces of over greasing especially on the underside of
the aluminium piston and cleaning any grease from the bottom of the internal air cylinder.
The only grease needed is a very light smear on the vertical walls of the cylinder and a
very light smear on the two red o rings before replacing the piston assembly back into the
cylinder. Any additional grease will lead to re-appearance of the occasional problem of
sticking closed.
o NOTE: The PTFE bush # 5835 was modified in Dec 2006 to eliminate this occurrence.
2. Another reason for the TAS valve to stick closed is the excessive use of the White Loctite sealant
that is used when inserting the PTFE bush # 5835. If too much Loctite is used and the top of the
bush is not wiped completely clean before inserting the piston assembly it can over time, set and
adhere the piston to the cylinder base.
o To solve the problem, remove the piston and rod assembly and clean off any traces of
Loctite sealant or silicon grease. A light machine oil smeared over the cylinder wall will
suffice on re-assembly, as an alternative to the heavy duty silicon grease, however a
small smear of silicon grease is still required between the two shaft o rings # 6004.
3. If the valve is still difficult to open, then check that:
o At least 7 bar pressure is available to power the valve.
o That the TAS valve been flushed correctly.
Damaged TAS Nose
1. It is most important not to damage the sealing surface of the 10mm hole in the TAS nose.
Damage usually occurs when the valve has been gelled up and mechanical attempts have been
made to rectify the problem.
o To solve the problem clean the gelled up nose surface with solvent and a cloth, or
alternatively, leave the nose in acetone for several hours to soften the residue before
attempting to clean the internal surface of the nose. On no account should any hard
metal scrape, or a 10mm drill bit, be used to clean this surface.
o NOTE: Any scratch, or pitting damage on the precision 10mm nose bore will result in a
leaking nose seal and eventual damage to the nose seal itself. In the event that this nose
seal surface is observed to be damaged as described then it is necessary to replace with
a new nose # 5852.