I bought a rotunda timing light for 6.9 on ebay. I followed the directions, but I'm not sure what it's supposed to act like.
The truck is an 87 F250 4x4 with a 6.9 and 5 spd.
First off, the luminous probe leaks so I have to hold the sending unit on or the air blows it off.
I set it to the recommended -20 degrees. When I run the motor up to 1400 the timing only changes to -19.5. Is this correct? I read that it should be advanced .5 for luminous probe and 8deg ATDC for injection line sender. Is this correct?
If all is well and good, how much can I advance this thing to check for better mileage and power. Right now I'm Nat Aspirated, but I am looking to put on a non-wastegated ATS in the near future.
I have a new pump on the way, so I was practicing on the old pump. So far if things are working right it advances to -13.8 as you progress from idle to 1400 then levels off at -19.5. When I jump the cold advance it jumps up to -8.5 for a second then levels off at -17.8.
I realize that I'm working with several unknowns here. First one being the timing device that I have no history of and part of it is not working properly. Second is that I have no idea how old this pump is. The truck has a documented 407,000 miles on it, with a rebuild on the motor about 68K ago. It still has the original injectors on it, it still had the original Ford heater hoses and top radiator hose on it when I got it. I have all new parts waiting on the pump to get here so for now I'm just guessing at things trying to figure out what is what so that I have some idea what I'm doing when the new pump gets here.
Taking this thing to a regular shop is out. All of them that I've called around here are crooks. The cheapest wanted $125 to set the timing. The worst was $450. I realize that everybody has to make a living, but people I've asked around here told me that they just do it themselves because the pump shops around here are all worthless.
Thanks for any help.
The truck is an 87 F250 4x4 with a 6.9 and 5 spd.
First off, the luminous probe leaks so I have to hold the sending unit on or the air blows it off.
I set it to the recommended -20 degrees. When I run the motor up to 1400 the timing only changes to -19.5. Is this correct? I read that it should be advanced .5 for luminous probe and 8deg ATDC for injection line sender. Is this correct?
If all is well and good, how much can I advance this thing to check for better mileage and power. Right now I'm Nat Aspirated, but I am looking to put on a non-wastegated ATS in the near future.
I have a new pump on the way, so I was practicing on the old pump. So far if things are working right it advances to -13.8 as you progress from idle to 1400 then levels off at -19.5. When I jump the cold advance it jumps up to -8.5 for a second then levels off at -17.8.
I realize that I'm working with several unknowns here. First one being the timing device that I have no history of and part of it is not working properly. Second is that I have no idea how old this pump is. The truck has a documented 407,000 miles on it, with a rebuild on the motor about 68K ago. It still has the original injectors on it, it still had the original Ford heater hoses and top radiator hose on it when I got it. I have all new parts waiting on the pump to get here so for now I'm just guessing at things trying to figure out what is what so that I have some idea what I'm doing when the new pump gets here.
Taking this thing to a regular shop is out. All of them that I've called around here are crooks. The cheapest wanted $125 to set the timing. The worst was $450. I realize that everybody has to make a living, but people I've asked around here told me that they just do it themselves because the pump shops around here are all worthless.
Thanks for any help.
