jcomp
07-29-2005, 19:47
For the last 6 months or so my truck has become increasingly difficult to start while cold. After it starts, it runs great. It makes good power and gets good mileage. While hot, it starts almost instantly, even after sitting a few hours.
However, cold starting is pretty ugly. It involves lots of cranking and almost-starts. The engine is getting fuel, lots of fuel comes out of the exhaust before the engine will finally fire up. When it does start, it runs very rough until it smooths out after about 5-10 seconds. It acts like the glow plugs aren't coming on.
The engine was rebuilt a year ago (approx. 6K miles), including a new 4911 pump, new 6.5TD injectors and new injector lines. Also, it has a timing gear drive set and a set of 6.5TD heads. Banks turbo and dual t-stats. For a lift pump I'm using an electric Holley red pump. I still have the stock dual filter setup with the secondary filter relocated to the firewall. My glow plugs are AC Delco 60Gs on a manual switch, using a ford starter solenoid as a controller. The cranking speed seems OK but I don't have a way to get a quantitative measurement. I keep the batteries on an automatic charger at all times, so I know they are fully charged.
It started great for a while but has slowly become more difficult to get going. Tomorrow I'm going to try hooking up a few more batteries to see if that helps, but I'm running out of ideas.
Here's what I've already tried:
1. Replaced the glow plugs. The plugs I removed were all good but I replaced them anyway since I had them out. I also tested my GP controller for proper operation and verified that voltage is present at all glow plugs while the controller is energized. Didn't help.
2. Primed the fuel system before starting. I theorized that my electric pump was allowing the fuel to drain back and the system was losing prime while it sat overnight. I replaced the filters and reprimed the system (easy with an electric pump) then tried to start. I also made sure all the hard lines were tight and there were no signs of leakage. No difference.
3. Adjusted the timing. I tried advancing and retarding the timing, as well as hotwiring and disconnecting the HPCA. Any change in the timing made starting more difficult or had no effect. I do not have an accurate timing meter so I can not tell what exactly it is currently. I've had the marks lined up since I built the engine and I've been using that as a baseline for the timing.
Does anyone have any suggestions of what I should check next? It's getting to the point that I would rather just drive my Ford than deal with this thing. If that's not a sign of how desperate the situation is, I don't know what is! :D
However, cold starting is pretty ugly. It involves lots of cranking and almost-starts. The engine is getting fuel, lots of fuel comes out of the exhaust before the engine will finally fire up. When it does start, it runs very rough until it smooths out after about 5-10 seconds. It acts like the glow plugs aren't coming on.
The engine was rebuilt a year ago (approx. 6K miles), including a new 4911 pump, new 6.5TD injectors and new injector lines. Also, it has a timing gear drive set and a set of 6.5TD heads. Banks turbo and dual t-stats. For a lift pump I'm using an electric Holley red pump. I still have the stock dual filter setup with the secondary filter relocated to the firewall. My glow plugs are AC Delco 60Gs on a manual switch, using a ford starter solenoid as a controller. The cranking speed seems OK but I don't have a way to get a quantitative measurement. I keep the batteries on an automatic charger at all times, so I know they are fully charged.
It started great for a while but has slowly become more difficult to get going. Tomorrow I'm going to try hooking up a few more batteries to see if that helps, but I'm running out of ideas.
Here's what I've already tried:
1. Replaced the glow plugs. The plugs I removed were all good but I replaced them anyway since I had them out. I also tested my GP controller for proper operation and verified that voltage is present at all glow plugs while the controller is energized. Didn't help.
2. Primed the fuel system before starting. I theorized that my electric pump was allowing the fuel to drain back and the system was losing prime while it sat overnight. I replaced the filters and reprimed the system (easy with an electric pump) then tried to start. I also made sure all the hard lines were tight and there were no signs of leakage. No difference.
3. Adjusted the timing. I tried advancing and retarding the timing, as well as hotwiring and disconnecting the HPCA. Any change in the timing made starting more difficult or had no effect. I do not have an accurate timing meter so I can not tell what exactly it is currently. I've had the marks lined up since I built the engine and I've been using that as a baseline for the timing.
Does anyone have any suggestions of what I should check next? It's getting to the point that I would rather just drive my Ford than deal with this thing. If that's not a sign of how desperate the situation is, I don't know what is! :D