changing the flame trap is pretty straight forward, it's defiantly worth doing it.

you may considering replacing the oil separator box while your at it. it isn't hard to do, it took me about an hour to do the whole job. just don't remove the oil return hose form underneath the box

you don't need to remove the intake manifold to do either of these things.

here's a picture of the whole system

http://www.ipdusa.com/Volvo-700/Filters-&-Tune-Up/PCV-Flame-Trap/PCV-Flame-Trap-1985-1991-B230FT-Turbo/p-70-251-865-5037/

Dan

You may want to buy a replacement Housing and Trap incase yours breaks in the process. The small nipple on the Housing gets brittle and can break.
I have a cleaned up spare on the shelf and sometimes while I'm doing an oil change I will just swap in the clean one. Then later I will clean th one I pulled from the car for the next time. Make sure the small hose going to the Housing is Clear along with teh Brass fitting that it goes to on teh Intake manifold. that's about all there is to it.


http://www.fcpgroton.com/product-exec/product_id/154/nm/1985_1987_Volvo_740_8_Valve_Flame_Trap_Nipple/category_id/10
http://www.fcpgroton.com/product-exec/product_id/169/nm/1985_1992_Volvo_740_8_Valve_Flame_Trap_Plastic/category_id/10

No, you do not have to remove the manifold. Look in the FAQ section, it is described in detail.
Some people have trouble finding FAQ's ..... top right of this page, click shortcut.
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David Hunter