INJECTION PUMP TIMING

Have read numerous posts lately regarding pump removal/re-installation on different models(but am/was wathcing the XT 190 thread) and Ed said something that has me puzzled;how do you time a diesel to within a few degrees? I am no mechanic nor do i pretend to be one on tv ,but pretty sure you don't hook a timing light up to the battery and #1 plug wire LOL! Just curios,thanks

The installing the pump is completey understandable, injEd said to leave mounting bolts loose to "tweek"final timing. How do you know how much to "tweek" without a tool,engine sound,smoke,hard starting? I am just asking about "DIALING" it in. Didn't mean to ruffle feathers, we have beans in the field yet too

Thanks, as bad as I hate to say it, I took it to mean you could rotate pump assembly like a distributor to tweek timing. Told you guys I was NOT a mechanic LOL

NO SIR you did not  LOL!! That just was the way I interpreted your statement . I am pretty good at changing oil and filters though !! In all seriousness ,our xt is gonna need the pump gone through sooner than later,if we can't find a rebuilder local(haven't looked hard yet) do you work on pumps from out-of-state? The farm is in N/C IND, thanks and my apologies for mis-reading your meaning on the loose bolts.

Starting to make sense now. Does 1 degree 1 way or another make a huge difference?

I work on pumps for people from all across the country. Many from right here on this board. 

If it hazes a slight amount of white smoke when idling, then a slight adjustment of timing will likely help. Advancing it in 2* increments is a good way to find what it likes the most. When finding optimum timing for running, may find it is harder to get started. The factory spec is usually a great place to start out with, and is usually a bit of a compromise in one area or another. When one is turned up for performance applications is when this is most important. Increasing a Roosa pump's fuel delivery has a direct affect on the beginning of injection of the pump. Turn it up, equals earlier beginning of injection. Normally a basically stock rebuild will run about as good at stock timing as it will anywhere. clear as mud? lol!

On a AC a little retarded timing can make them start better. More like a JD or Ih lol.      MACK

The digital timing meter or a light can only be used on a roosa system if you know what the meter needs to read. You can't put one on a D21 which times to 34*, and expect to see 34* on the meter, unless you can apply full load like on a dyno. The roosa pump beginning of injection varies with load changes. Those meters were designed for the automotive diesels which used Roosa pumps, but incorporated light load advance mechanisms, and they had come up with specific timing specs for use with the meters.

that will explain why dads 185 starts so hard! when he had the pump redone, his mechanic buddy installed it and advanced it 3 or 4 degrees and now starts terrible, but runs awesome once running. my 7020 I have set at 18 degrees BTDC and it will start no pre heat or starting fluid on a 40 degree F day no problem! ill have to do some fine tuning on dads 185! I was always intimidated but diesels aswell but not anymore there the basic principle of a gas distributer, but need to be timed right for best results!

should say , thanks