ls1mike
$50 Site Donor 2025
Well...The boys truck needed injectors. So here goes.
We recently replaced the CP3 pump and drove it about 500 miles. Noticed the crankcase was
filling up with fuel. So we figured injectors or a leak from the injector return lines.
We pulled everything apart (the last person in there was not very good, reused fasteners,
many were stripped out, took a bit of time and patience to get it all apart)
We replaced the injectors with rebuilt units from what we thought was a reputable place, new return lines, new billet injector hold
downs, ARP fasteners in the hold downs (torqued to 55ft/lbs) new injector cups with red Loctite.
all new crush washers, all new ARP valve cover fasteners. Also installed a Fass
Lift pump. Truck started up and ran perfect for about 45 minutes.
Then the truck went into Limp mode, which I don't really think that is what they call it.
It shut down half the injectors, with the following codes P2149 P0202 P0203 P0205 P0208.
We took resistance readings through the injector pigtails and all 8 injectors read 0.6 Ohms. So we
believe those all checked out. We then pulled the connectors off the FICM and read through the wiring
harness to the injectors. On C2 we went from pin 118 to following pins for fuel injector command. 115,
116, 120, 121. They all read. 0.9 Ohms when the engine was cold.
Even though our code was for those injectors (2, 3, 5 and 8) we also read through C1 we went from Pin 3 to the
following pins: 1, 4, 61, and 62, They all read. 0.9 Ohms when the engine was cold.
That seems like this should be a good reading going through the harness and all the injector readings
match.
We inspected the wiring harness over the top of the alternator for bad or frayed wiring we did not see
anything. (pretty common at that age) Verified chassis grounds. I have dealt with a ton of pushed or
bent pins on Submarines and we did not see anything that looked bent or pushed in the connectors.
Finally give up and pull it all back apart read the injectors individually 3 of them are bad. Slight anger lol.
Replace injectors with ones from Lincoln Diesel. Starts right up runs awesome...
Now fuel in the oil...
Turns out the injector return lines will leak (we knew this and were careful putting them back in) and it seems to be a common come
back when the injectors are done by a lot of mechanics.
Pull it back apart, pressurize the return side, some of the crush washers did not seal.
Get new parts again, bolts, return lines and crush washers. Pressurize it no leaks. This time from Lincoln Diesel.
The parts were quality compared to what we originally received and installed. I should have monitored more of what
the boy purchased.
All back together now thing runs beautiful.
Just in case you wanted to buy a cheap LB7 these are some things to look for. I know more about this dang thing than I ever cared too.
We recently replaced the CP3 pump and drove it about 500 miles. Noticed the crankcase was
filling up with fuel. So we figured injectors or a leak from the injector return lines.
We pulled everything apart (the last person in there was not very good, reused fasteners,
many were stripped out, took a bit of time and patience to get it all apart)
We replaced the injectors with rebuilt units from what we thought was a reputable place, new return lines, new billet injector hold
downs, ARP fasteners in the hold downs (torqued to 55ft/lbs) new injector cups with red Loctite.
all new crush washers, all new ARP valve cover fasteners. Also installed a Fass
Lift pump. Truck started up and ran perfect for about 45 minutes.
Then the truck went into Limp mode, which I don't really think that is what they call it.
It shut down half the injectors, with the following codes P2149 P0202 P0203 P0205 P0208.
We took resistance readings through the injector pigtails and all 8 injectors read 0.6 Ohms. So we
believe those all checked out. We then pulled the connectors off the FICM and read through the wiring
harness to the injectors. On C2 we went from pin 118 to following pins for fuel injector command. 115,
116, 120, 121. They all read. 0.9 Ohms when the engine was cold.
Even though our code was for those injectors (2, 3, 5 and 8) we also read through C1 we went from Pin 3 to the
following pins: 1, 4, 61, and 62, They all read. 0.9 Ohms when the engine was cold.
That seems like this should be a good reading going through the harness and all the injector readings
match.
We inspected the wiring harness over the top of the alternator for bad or frayed wiring we did not see
anything. (pretty common at that age) Verified chassis grounds. I have dealt with a ton of pushed or
bent pins on Submarines and we did not see anything that looked bent or pushed in the connectors.
Finally give up and pull it all back apart read the injectors individually 3 of them are bad. Slight anger lol.
Replace injectors with ones from Lincoln Diesel. Starts right up runs awesome...
Now fuel in the oil...
Turns out the injector return lines will leak (we knew this and were careful putting them back in) and it seems to be a common come
back when the injectors are done by a lot of mechanics.
Pull it back apart, pressurize the return side, some of the crush washers did not seal.
Get new parts again, bolts, return lines and crush washers. Pressurize it no leaks. This time from Lincoln Diesel.
The parts were quality compared to what we originally received and installed. I should have monitored more of what
the boy purchased.
All back together now thing runs beautiful.
Just in case you wanted to buy a cheap LB7 these are some things to look for. I know more about this dang thing than I ever cared too.
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