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Injector pump

Posted: Tue Feb 21, 2012 10:46 pm
by brinky
Here comes another question ...

Whilst running the major today with the bonnet up I noticed that the right hand pipe had diesel spraying out where it goes into the injector pump.
Is it a matter of tightening the nut or is there some sort of seal in there?
Thanks again

Re: Injector pump

Posted: Wed Feb 22, 2012 2:33 pm
by Pavel
Go on, Brinky, threaten it with a spanner -- it aint got no seal.

Re: Injector pump

Posted: Wed Feb 22, 2012 5:27 pm
by Brian
As Pavel says :D The ends can break off the pipes, they crack around the olive. Be very careful when working with diesel under pressure, if it penetrates the skin it could mean amputation or death in the worst case.

Re: Injector pump

Posted: Wed Feb 22, 2012 6:06 pm
by brinky
I'll bare that in mind... If I threaten it with a really big spanner will it fix all the problems ? :lol:

Re: Injector pump

Posted: Thu Feb 23, 2012 1:09 am
by nzMark
Hi Brinky, just ensure it is not loose, you can screw its neck off if you use anything to heavy, use common sense

Re: Injector pump

Posted: Thu Feb 23, 2012 2:50 pm
by Pavel
Realistically though, if after a tweek with a spanner it still leaks, remove the pipe, cut the old olive off with a junior hacksaw, clean the pipe end up with fine emery, or wet & dry, and fit a new olive. You will have to, gently using fingers only, slightly re-bend the pipe. When re-fitting, firm, but not excessive, pressure use of a spanner is required in order to slightly compress the olive onto the pipe. Loctite also market a product specifically for compression fittings called '518 Flange Sealant' -- it's good stuff.

Re: Injector pump

Posted: Fri Feb 24, 2012 8:44 pm
by Kim
This one for Brian I think, but wouldn't shortening the pipe a little throw off the timing a small amount on that cylinder?

Re: Injector pump

Posted: Sat Feb 25, 2012 1:00 pm
by Dandy Dave
Yes, Injection lines on diesels are suppose to be all the same length. With that said, I do not think a quarter of an inch out of a line would make much difference in our old slow turning Majors. Dandy Dave!

Re: Injector pump

Posted: Sat Feb 25, 2012 4:25 pm
by Pavel
I remember that question being part of an exam paper I took many moons ago. The short answer is No - provided that the injector and pipe do not leak or dribble. The illustration given was of a pipe filled with balls. Place another in one end and one pops out the other end. Cut the pipe in half, and the same effect happens. A diesel fuel line is kept full and, rather like unequal brake lines, irrespective of length, pressure imparted by the pump at one end is transmitted to the other end in equal measure. In such short runs friction losses are not a consideration.
Pavel

Re: Injector pump

Posted: Sun Feb 26, 2012 2:10 pm
by Dandy Dave
Pavel is right about full lines and pressure. If the injector is set to pop off at say 1,800 PSI, it will not pop off until that pressure level is met. The little amount that the lines may stretch under pressure, and the fuel in the line will compress, would be very small, and almost unnoticable. Dandy Dave!

Re: Injector pump

Posted: Sat Apr 14, 2012 10:55 am
by brinky
Pavel wrote:Realistically though, if after a tweek with a spanner it still leaks, remove the pipe, cut the old olive off with a junior hacksaw, clean the pipe end up with fine emery, or wet & dry, and fit a new olive. You will have to, gently using fingers only, slightly re-bend the pipe. When re-fitting, firm, but not excessive, pressure use of a spanner is required in order to slightly compress the olive onto the pipe. Loctite also market a product specifically for compression fittings called '518 Flange Sealant' -- it's good stuff.
Ok, I have done this, and it has cured the leak :D
Since doing this and fitting a new fuel filter the engine does not rev evenly, it revs high then low making it very difficult to maintain an even speed.
Have I caused this problem ???

Re: Injector pump

Posted: Sat Apr 14, 2012 12:11 pm
by henk
Brinky,

On the end of the right side of the pump is a screw/bold. Loosen the nut and you can turn it. With this it could be possible to adjust the hunting. Remember the setting when you start. Count the rev of the screw so you can put it back on the original setting.
Also check if the air pipes aren't leaking with some soap.

Re: Injector pump

Posted: Sat Apr 14, 2012 12:45 pm
by BearCreek Majors
Sounds like you may have some air in the system as well from changing the fuel filter. Start cracking the bleeders open one at a time from the supply side working to the injector pump to be sure all the air has been evacuated. Should be two on the filter housing and one on the injector pump. If you lift pump has a glass bowl don’t worry about the air bubble in there, it will eventually disappear.

Pat