Fuel Pump Torque Value

[Rob1986EBKO]

1986 175ETLJ what is the torque value for the two fuel pumps? Also what is the theory of operation they dont appear to be electic or have a shaft driving them. Thanks

[mygrady1]

Is there no # on the bolt head. Mine has a 9 stamped on them. If so, it's 6 and not 9 ftlbs. You can crush gaskets if not careful.

[99yam40]

My guess would be that they run off of the vacuum/pressure pulses of the crank case of the different cylinders they are bolted onto

[boscoe99]

The number on the head of a bolt is the bolt size, not the torque value.

Torque value for an M6 bolt is 5.8 lb-ft, unless the service manual specifies otherwise.

As 99Yam40 notes, the mechanical fuel pump is pressure/vacuum pulse activated.

[robert graham]

And if your pumps have never been rebuilt or replaced then now would be a good time to put a couple of new ones on....sorta like with the water pump impeller. The pumps are fairly inexpensive($50 or so) and the diaphragms just can't last forever.....There's a gasket between the pump and the crankcase which should be replaced also.