Jaguar Repair: vaccum servo, gauge readings, speede

Question
QUESTION: mr howard  why ods it take so long for the vaccum servo to work after i cut on my ac on 85 xj6 jag. how much freon do it take to charge system i have put in 3 12 oz cans lo pressur side read 42 at out side temp 86 at idle when i speed up to 3000 rpm ti goes down in the green to 20 i replace vent valve goingto gas tank some times pressur sometime no pressur

ANSWER: Hi James,

Your gauge readings should be (after the system was evacuated and R-12 installed) 50 PSI on the low side and not over 250 PSI on the high side. Most that I have done use 2 to 3 cans unless you are using the alternative gas that is Propane based and which case you usually can't get more than about 1 and a half cans in. Don't put 134 in the system.

No telling why the vacuum is slow on the system. check both hoses going into the firewall on the right side down low. You might try using a mighty vac hand pump to test the system for leaks.

Howard

---------- FOLLOW-UP ----------

QUESTION: mr howard i have vaccum the vaccum moter  dont work. i have changr vaccum moters and switch also and relayon left sidr. please send wireing digram.blower moter dont work on low speede ither thanks on info on 134 freon do i need to take that out.

Answer
James,
If it were mine, I would have the 134 evacuated by one of the retrieving systems, as 134 is poisonous in it's natural form. R-12 is only poisonous when burned. 134 is a poor refrigerant next to R12 and R12 is poor next to the propane based refrigerants.

The diagrams are on my web site at http://mg-tri-jag.net/JagACEle11x1.jpg  and change the ending to  JagACEle21x1.jpg for the other half.

Howard