I modified the valve cover to accept a rubber grommet for a pc valve,
made a baffle plate and mounted it to a cam bearing cap,
ran a hose from the valve to the flame trap nipple (minus the flame trap),
and plugged the line from the breather box.
(I never had a crankcase explode on any of the Fords Ive had over the years.)

Seems like an awful lot of trouble to go through for questionable results.
When the whole flame trap replacement kit costs $2.50, I just have one question: WHY?
--
Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K

1. tired of replacing seals
(even if you keep the flame trap clean, a back fire can blow a seal tho it usually just blows the hose off)

2. inspection of pcv valve consists of popping it out and shaking it

3. flame trap replacement kit $23.70 +s/h (including all the molded hoses,especially the return hose in the oil seperator which is a real pain)
1306196 PCV Hose all 240 models $12.00
3507245 Breather Hose Flame Trap to Air Box (88-93) $ 8.75
3501708 Flame Trap Hose (88-93) $ 1.45
1389657 Flame Trap (Plastic) $ .50
3501707 Flame Trap Nipple (88-93) $ 1.00

4. took me 15 minutes to make a hole in the filler cap for the rubber grommet for the pcv valve using a dremel tool

5. pcv valves are $1.29 at wally world, 5/8 fuel hose $.50/ft
(they dont have flame traps tho)

72 142 ??? modification apparently done in sweden
89 244 329k (modification @ 142K)
97 964 114k (modification @ 22K)

This sounds like a reasonable modification. The test is in how well this scavenges out the blow-by and other vapors from the engine. What sort of vacuum do you feel at the oil filler cap when the engine idles? (refer to the jiggle test or something similar)

My '80 B21a has the flame trap on the valve cover, so did my previous '77. But my mom's '84 B21a has the oil trap-flame trap set-up on the block (valve cover is different).

--
1980 245 Canadian B21A with SU carb and M46 trans

Not sure exactly how you did those plumbing changes. Have you in effect made a circuit from the crankcase up to the valve cover with a PCV in line. Have you made provision to burn off or vent the crankcase fumes. If not you will build crankcase pressure and blow oil out the seals.

The purpose of the flame trap is to stop a flame front created by an intake manifold backfire from travelling into the crankcase and exploding there. Kind of a remote cahnce but I guess they thought it could happen.
--
David Hunter

a circuit from the crankcase to the valve cover already exists, otherwise the oil from the cam could not drain back to the pan. i am just venting the engine from up top where there is less windage. the flame trap does not prevent a backfire from blowing seals....a pcv valve does, and it stops the flame also.
older cars typically had a breather off the side of the block vented to down to the ground, when the blow by got bad, they would dribble....volvo took that breather and connected it to manifold vacumm thru a "flame trap" while the rest of the automotive world sucks the vapors from up top via a pcv.

Fair point, but Volvos last about twice as long as other cars. One reason might just be because they have a better way of scavenging out blow-by gases so that they don't contaminate the oil.
Yes, I see the point about equal pressure top and bottom, but if you vent at the top the gas has to make its way up the connecting passages from the crankcase, nicely contaminating the returning oil on its way down. Aren't there chemical production processes using this principle of blowing gases up through liquids trickling down towers?

I am not sure I think this is a good idea. For a start you have by-passed part of the crankcase breathing circuit. Won't that at worst cause a pressure build-up, and at best mean that blow-by gases are left to contaminate the oil instead of being sucked out?
Crankcase explosions can happen - there was someone on Brickboard had one a month ago.
Better would be to buy the replacement kit, or make one up, to reposition the flame trap in a more accesible place and then keep it clean.

the pressure in the crankcase is the same as the pressure up at the valve cover,
otherwise the oil from the cam would never see the oil pump again, it all has to drain back from the head.