Timing

[ironworker40]

One of the members here contacted me thru the timing registry and he came over and we timed his truck today, in the snow. So he has a 94 factory turbo, yes I checked the vin, upon initial check he had pump marks line up exactly, rebuilt turbo pump, bb code injectors, 6psi fuel at filter (he had a gauge were the vacuum switch would normally be) and he was at 14.3 with pulse method. So to get him at 8.5 we wound up with pump mark on the left side (drivers side) of the housing scribe mark not on the right were it would normally be. Anyone want to guess who rebuilt the pump? Drum roll please! Pensacola Diesel. So this is another example that we CAN NOT relie on pump marks for timing.

Maybee Mell can chime in on why the pump would have to be turned to the wrong side of the line, obviously the rebuild is not high quality.
Has anyone else ran into this problem?
The owner texted me on his way home and said he was very pleased with the way it is running. I told him he will get a big surprise when he starts it cold tomorrow. I'm sure he will be even more pleased when the roads clear up and he can wind it up, they are slick right now.

 

[icanfixall]

As we have posted before. The factory lines only means something with the original pump on that engine. Any other pump is timed internally differently. The way I understand the internal timing is this. Once the pump is disassembled you loose the timing marks. nothing ca be done to maintain the way the pump was made of internally timed. Nothing inside the pump tells the rebuilder where to set the timing pieces so it can be the same before it was taken apart. We just have to agree those marks on the pumps and the gear housing relates to nothing specific for a known degree of timing. While it is a mark. The mark means you are here but nobody knows where here is till to put a meter on it. Its a sad way these pumps are rebuilt but thats why I help others with meter rentals. A few years ago I timed a members truck at the get together at towcats. I think I did 15 or so trucks that day. anyway one came in -4 degrees...... That negative degrees. Not advanced. We had a hell of a time getting it to 8.5 advance too. I think someone before him had removed the pump and the gear. then skipped a tooth when they put it together. When the pump is off one gear tooth it places the pump way over towards the passenger fender. It looks bad too.

 

[ironworker40]

So Gary if a pump is a tooth out it can still be timed? I thought if it was a tooth out it would not time. Good to know.

 

[icanfixall]

The problem being a tooth out of gear time is the pump MUST be turned over so far its not easy to work on. Now is these gears end up 180 degrees out of time it will NEVER time correctly but it will run. It runs horrible but it runs. Just ask the dog catcher. He was wanting some advise on a poorly running customers truck that just got a new injection pump. Said it was running horrible. I asked if the gear cover was removed with the pump. Sure nuff it was. We talked thru this and it was not gear timed correctly. The shop that "fixed this" had the injection pump "Y" mark lined up to the cam dot mark. So Ron repaired it and it ran great. Ron is a smart guy when it comes to the idi engines and what they can do.