pump timing

[bobb]

are all (generaly speaking) diesel engines timed @#1 tdc compression stroke?

 

[John C.]

Are you talking pump timing or valve timing?

All the engines with Bosch style pumps that I've worked on were timed at some point before top dead center. Cummins engines with PT pumps are timed on the injectors with the crank at specific marks on the balancers or gear trains. Many of the Cat engines used a timing plate installed on the fuel system drive gear and the crank set at a certain point and then the gear is locked down. The fuel pump has a place for a pin and the pump is turned until that pin locks the pump rotation and then the pump is installed on the engine. As I recall the Cummins B and C series engine are set this way but don't need the timing plate. The crankshaft is set at a certain point and the pump gear is locked to the pin timed shaft of the fuel pump. Detroit engines have a measuring stick that you use to set the rocker heights with for injector timing.

There are probably many more ways to set the pump timing. I'm only relating what I have experienced.

 

[willie59]

Most all time on #1, but not necessarily on TDC. Most applications vary between 2 to 15 degress BTDC. There are even exceptions to that, but just generally speaking.

 

[bobb]

i guess im using old literature....oh it was pump timing that i needed the info on.. thanks guys...oh one more to throw into the mix... how do you time a duetz with individual pumps? im tinking with a dial indicator?

 

[John C.]

I've seen single pumps adjusted was on Fairbanks Morse engines. You had a special dial indicator tool that plugged into the end of the fuel pump. You had shims under the pump that adjusted timing and the amount of stroke. You barred the engine over and watched the indicator noting how far it traveled. You then added or removed shims to get to the specified amount of travel.

Another way I've seen it done was on Onan diesel engines. As I recall you pulled the check valve out of the end of the injection pump and then used the priming pump to push a continuous flow through the pump. When the flow stopped should coincide with a mark on the balancer or flywheel. I don't recall if you used shims under the pump or had some other way of changing where the flow stopped.

 

[willie59]

If you're talking about a Deutz 1011 model, they use a belt to drive the cam. The cam operates the individual cylinder injector pump modules. Timing is set by a rather complex process using timing pins for cam and crankshaft and rotating the notched belt gear on the crankshaft.

 

[bobb]

i understand about the timing pins and the goofy belt drive but how do you time the individual pumps. they have oblong holes that go over studs in the block that would allow you to rotate the pumps a bit. i figger thats the adjustment for the timing. some of these things run rough. especialy the three bangers. if i could verify the pump timing then at least i did the best i could.

 

[tctractors]

Just thought it might be worth saying, on Deutz engines No1 cylinder is near always on the Flywheel end of the block, Cat and Cummins No1 cylinder is at the fan end of things, lots of the individual pump to cylinder engines in their range have a poly-vee belt driven fuel pressure pump running at about 3 bar (min 30 psi) to give you something to do.

tctractors

p.s. the cylinder No's are often set into the side of the block on Deutz, hope this helps bobb???

 

[bobb]

never noticed the cylinder numbering. im still interested to know how to time the individual pumps.

 

[tctractors]

bobb its a help to know what spec engine you are talking about ( whats it in ???) the common inline pump fitted to Deutz engines now is Motorpol (Poland) as Bosch stopped producing pumps for them due to to small numbers required (I think ?)

tctractors

 

[bobb]

this would not be in any particular machine as i come across them in all kinds of machines. im just interested to know the general timing procedure for future reference.

 

[tctractors]

bobb, to give you the correct spec's I would need to know the engine series, if its the small 4 pot motor that is fitted to the volvo 140BLC excavator (D4D) the pumps are shimmed, there is a number stamped onto them, from this number its possible to set the correct shim hight, it might be a thought to also study the injector position, they have a dimple-dot on one side, this is fitted towards the valve gear ( if I remember correctly) and sets the spray holes in the tip to the correct part of the piston, it is possible to spill time the pumps.

tctractors

 

[bobb]

i mostly see the 1011 series engines. i dont think they are shimmed cause they have oblong mounting holes so you can turn them a bit cw or ccw.

 

[thepumpguysc]

Pumps are shimmed, the oblong holes are used to set equal delivery, but predetermined by the rack setting.
If you look at the pumps you'll see a small "plug" by the fuel inlet.. the proper way to install these pumps is> pin set the rack and remove the "plug" on the pump and install a holding pin thru the plug hole. Lower the pump into the block until it engages with the rack, tighten down the pump and remove the holding pin and reinstall the plug.
VERY IMPORTANT to make sure the rack moves freely after EVERY pump is installed because its easy to miss the rack, thats why the holes are oblong, it gives you some wiggle room.. it only takes 1 pump to make an engine run-away.
Hope this helped. As far as the timing goes, you measure the cam lift to deck height and shim according to spec for your specific engine with a depth mic..

 

[bobb]

so the rack is locked in full throttle like a detroit, and the pumps are set accordingly? and the shims will time the pumps.