Crush Washers

aa3jy · #1 (**permalink**) 10-26-2011

Is there a particular way crusher washers are facing when replaced on the fuel low pressure side of a diesel? I noticed that most crusher washers have a flat side and a somewhat rounded side..is there a reason for that..can't find any references to that question.

kd3pc · #2 (**permalink**) 10-26-2011

the curved or dimpled side should go to the bolt or nut side that is applying the tension to the joint, the thought being that spreading out that torque should apply equal pressures to the entire joint...

they are single use, and quite critical to the long term function....

aa3jy · #3 (**permalink**) 10-26-2011

Quote:

Originally Posted by kd3pc

the curved or dimpled side should go to the bolt or nut side that is applying the tension to the joint, the thought being that spreading out that torque should apply equal pressures to the entire joint...

they are single use, and quite critical to the long term function....

Your reasoning sounds correct..do you have a reference that I can verify?

kd3pc · #4 (**permalink**) 10-26-2011

none whatsoever....I even have people tell me they are not needed at all...and they throw them away, or ....worse

this is from years of working on fuel systems (and other car/MC, heavy equipment) that use them and the side affects/cost of not using them.

You can google Belleville (sp) washer to see the theory (and the inventor) behind them and most pictures indicate the bell to the bolt side...that was the acronym that I used way back when I learned FI systems....

YMMV

aa3jy · #5 (**permalink**) 10-26-2011

Looked at Bellevue Washer site..they refer to spring washers..Basically what I have are flat copper washers with a some what of a rounded face on one side and a flat face on the other..but both sides are basically flat as compared to the Bellevue spring washer..I guess the same principle applies.

Capt Len · #6 (**permalink**) 10-27-2011

These washers can be annealed for reuse if necessary but you should carry spares anyway. I've spent enjoyable time searching in the bilge because the owner didn't. Especially true for injectors.

luck66 · #7 (**permalink**) 01-12-2012

Wish I had this information a few years ago when I was having trouble bleeding my fuel line. Got new washers, all works good now. I now have spairs.