[Fot] TR6 PI question

[Enquiries Road & Track]

quickly,,,,, several possible issues............
1 injector has failed
the 2 internal O rings in the metering unit have failed
the shuttle has jammed at 1 end
one or more check valves have failed

if the injectors dont "pulse" nicely when pulled out, then the fault could
be either an injector or the metering unit

whislt running, blank off the injector port with a rag or cork, and gently
pull open the pintle tit of the injector that is not spraying. dribbles
indicate its getting fuel but it could still have a failed outlet valve or
internal o ring. no fuel indicates metering unit internal fault

sometimes, if its just dribbling a bit, you can solve this by gently
pushing back the injector nozzle into the body, then tap the end fitting
where the nylon hose screws on. this can get them spraying again

once removed, if the injector 'rattles" then it has internally failed. most
like the circlip has fallen off and the O ring has shrunk. both easily
solved

here are the simplistic 'repair instructions" for the metering unit

take the complete metering unit off car with engine at TDC as per repair
manual
dont lose the plastic drive dog

check it rotates freely by moving the tang where the plastic drive dog goes

check then remove all injector pipes.. they are stamped 1-6 at injector end

remove 4 outlet valves and 2 outlet banjo valves (18 & 19mm ring spanners).
if the rubber 'bung seals' come out with them, they have shrunk and need
replacing. if not, pick them out with a suitable bent-end picker. dont use
a screwdriver or large tool, and dont scratch their inside faces

 remove the vacuum control unit from metering distributor and put it aside
(dont disassemble)

check the fuel diaphragm is not split. hold it up to the light and pull
gently looking for splits

tip the distribution unit on its 4-bolt end and check the shuttle pin falls
out freely  if the inner barrel falls out as an assembly, the internal O
rings are stuffed

test each outlet valve you take out by sucking on its inside 'tit". a
perfect one will hold on your tongue for ages. if it wont  seal at all by
sucking, the flap valve inside it is stuffed and they need repair or
replacement

wash everything in white spirits/kero

replace the 2 internal o rings with Viton versions (readily available) and
a tiny smear of rubber grease

refit the barrel without bung seals

align the barrel then fit new/good bung seals with a tiny smear of rubber
grease, pressing them home with a flat ended dowel or similar (care, no
swarf gets in)

refit 4 outlet vales with new O rings or dowty washers (depending on
model--both readily available)

refit the metering shuttle without any grease/oil and check it moves freely.

refit the control assembly taking care not to damage the diaphragm

test the control unit diaphragm is not leaking

refit and drive away happy

Terry