you know where the Flame trap is located on your Volvo ? Probably
not, I guess.. You better find out soon, it could save you
lots of problems and money later !!
the used Volvos I bought in the past or inspected for others had flametrap
problems, most had completely blocked flametraps. Recently, I
inspected a Volvo 740 owned by a lady in our village and yes
....... there was an old type flametrap completely blocked. The problem was that the owner of the
car had the Volvo serviced by a local garage not familiar with
Volvos and this flametrap was probably the original one from new.
Luckily, I keep some spares for our own fleet, and I was able to
fix the problem for her and probably saved her an expensive seal
older Volvos like my 1968 Amazon (B18) crankcase pressure
is released to the air through an oil trap on the side of the
engine block. On later engines the gasses are re-circulated to the
intake manifold to avoid release in the atmosphere.
flametrap is installed in that circulating hose on the 200 series
Volvos. The flametrap itself is a little disc (top photo) of the
size of a NZ$2 coin. The old type flametraps were of the metal
wound type as shown in the top photo, however they were replaced
about 10 years ago by a plastic type with larger openings and
which is a lot easier to clean. In particular the older type flametraps
collected oil and other dirt and in the end plugging the flametrap
A blocked flametrap means crankcase pressure build-up and forces
oil past the seals causing oil leaks so common with the older
Volvos or even blowing out seals completely (I speak from
experience) and losing most of your engine oil !!
Replacing the flametrap is just regular preventive maintenance. On
1976-80 models you'll find the trap at the cam cover. On 1981-88
models you'll find it under the intake manifold on the side of the
block. Access is not easy, but by following the hoses as shown on
the photo of my 1988 240GLT engine, you will find it.
simplify access to the flame trap, you could remove the bellows
from the throttle housing. Now you can much more easily reach the
flame trap and you can also clean the throttle plate. However, if
you know what you are doing, it is possible to remove the
flametrap unit without removing the bellows. It is always a hassle
putting the bellows back on properly.
of the air/fuel unit
off the oil seperator
flametrap housing can be pulled off the oil separator and the
hoses, a big one and a small one, can be pulled off the flametrap
housing. The plastic piece is probably very brittle. Be careful
when removing this piece, it is very easy to crack the
"Y" piece that attaches to a vacuum hose. Use a pair of
needle-nose pliers and be gentle! It can be done without removing
any other equipment. Make sure that all the hoses and the nipple
on the manifold are not blocked. On 1988 and later models the
flame trap is nestled in between the cylinder head and intake
manifold, it is easily accessed from above. Also some people have
re-located the flame trap that way for better access and I think
even sells a special kit for that.
flametrap costs around NZ$10 and is available from your Volvo
Service Dealer. Do NOT clean the old metal wound flametrap but
REPLACE it by a new plastic one. Replacement of engine seals means
removing the gearbox and would cost around NZ$500.
you are doing this job, also ensure that all hoses and
nipples are clean
and not blocked. Inspect all hoses for cracks or split
hoses. Any problems with hoses could unsettle your engine or create starting problems. I found this
split hose on a bypass valve when servicing the flametrap
on my 240GLT.
had my fair share of crankcase pressure build-up on my old 1982
Volvo 244GLT over the years because of a blockage that the (Volvo)
garage couldn't find. After many seal replacements I found the
culprit myself. Fed-up with the ongoing problem, I removed the
intake manifold and fuel injection unit to access the oil separator
mounted on the side of the B23E block and found part of an old
metal wound type flametrap pushed in the exit (top) of the oil separator,
it was stuck and blocked circulation completely, thereby causing
pressure build-up in the crankcase which blew the seals out when
revving the engine !! Somebody had knowingly done that. Maybe the
previous owner or his mechanic. This problem had cost me over NZ$1000
at that time (10 years ago).