Saturday, February 27, 2010
Shakedown
Since the last post, the clutch has been replaced. The kit included a heavy-duty clutch, pressure plate and release bearing (from Sunbury Brakes in Australia, here is the kit).
Since the kit did not include a pilot bearing, I had to find one on my own. It turns out that the pilot bearing from the stock gasoline Trooper engine is the same, so I used that application to order a new one from NAPA - works without issue. The transmission input shaft, release lever, release bearing, bearing retainer clip, etc. are all the same between the gas and diesel transmissions. I ordered a rear main seal from an Isuzu industrial dealer, giving them the engine model as the application.
Two problems have grounded the Trooper since the clutch was replaced. The first was a fuel starvation issue, which I traced to the sock filter I had added to the bottom of the fuel pickup tube I fabricated in the fuel tank. I had to remove the tank, pull the pickup assembly and remove the filter, which was completely stopped up. I think the biodiesel melted it a bit, as it seems to be made of nylon. I just left the pickup tube bare - I have a prefilter installed before the main filter/separator assembly, and any junk that comes up from the tank will be caught in the (very cheap and easily accessible) prefilter. The sock filter was meant to protect an in-tank electric fuel pump from debris; not necessary in this application. I also took the time to repair the wiring for the fuel gauge, and I now know how much fuel I have in the tank.
The second problem was a very sudden loss of heat on the freeway. I exited and pulled over, and quickly confirmed my suspicion that I had lost all coolant. After towing the truck home and inspecting the cooling system, I found that an expansion plug (also known as a freeze plug or frost plug) had fallen out of the block.
This was the same plug that had popped partially out a couple of winters ago when I had inadvertently left some water in the block (thought it was drained totally; I now will always leave antifreeze in the system, no matter the circumstances). I tapped it back in at that time, but I guess it was crooked or damaged.
Luckily, this particular plug is the easiest one to access on the entire block - between the starter and injection pump on the driver's (or left) side of the engine. Determining what size plug to get was the most time-consuming part of replacing it - while the plug is the most accessible, access isn't all that great, and I couldn't get any sort of measuring device close enough to get a reading. I tried to order the plugs from the stock gas engine block, but they were too small. I finally found a website with parts diagrams of the block (see here) and was able to determine that the large plugs are 45mm in diameter. Of course, no local parts houses had a plug this size.
Mr. Lemond, Isuzu parts guru, sent me a stock Trooper diesel plug (C223 engine from '86-'87 also has 45mm plugs) as well as a block heater made for this size opening. I was able to install the block heater by carefully choosing the angle of installation (the plug is behind the oil pressure sender and the fit is tight - the electrical connector has to be at about 1 or 2 o'clock to clear it). I also had to remove the oil pressure sender in order to access the area, and tapped the block heater in by using long socket extensions inserted through the fender skirts in the driver's side wheel well. Once it was tapped in (to seat the o-ring), I tightened it from the same wheel well location.
Installing the oil pressure sender was tricky. I had to trim a small amount of rubber off the end of the heater's electrical cord to gain some additional clearance. I then inserted the cord, and spent a great deal of time trying to get the sender's threads started, as it was rubbing on the electrical cord connector. Once it was started, it went in smoothly, and there may even be a hair's breadth clearance between the cord and the body of the sender.
On balance, I am glad the plug fell out, as it gave me an excuse to install a block heater, something I have been meaning to do for some time. I am glad there was no damage to the engine when the coolant was lost. I've driven it a bit since then and all seems well - must be the cool-running diesel and overall ruggedness of the 4JB1-T that saved me.
Since the kit did not include a pilot bearing, I had to find one on my own. It turns out that the pilot bearing from the stock gasoline Trooper engine is the same, so I used that application to order a new one from NAPA - works without issue. The transmission input shaft, release lever, release bearing, bearing retainer clip, etc. are all the same between the gas and diesel transmissions. I ordered a rear main seal from an Isuzu industrial dealer, giving them the engine model as the application.
Two problems have grounded the Trooper since the clutch was replaced. The first was a fuel starvation issue, which I traced to the sock filter I had added to the bottom of the fuel pickup tube I fabricated in the fuel tank. I had to remove the tank, pull the pickup assembly and remove the filter, which was completely stopped up. I think the biodiesel melted it a bit, as it seems to be made of nylon. I just left the pickup tube bare - I have a prefilter installed before the main filter/separator assembly, and any junk that comes up from the tank will be caught in the (very cheap and easily accessible) prefilter. The sock filter was meant to protect an in-tank electric fuel pump from debris; not necessary in this application. I also took the time to repair the wiring for the fuel gauge, and I now know how much fuel I have in the tank.
The second problem was a very sudden loss of heat on the freeway. I exited and pulled over, and quickly confirmed my suspicion that I had lost all coolant. After towing the truck home and inspecting the cooling system, I found that an expansion plug (also known as a freeze plug or frost plug) had fallen out of the block.
This was the same plug that had popped partially out a couple of winters ago when I had inadvertently left some water in the block (thought it was drained totally; I now will always leave antifreeze in the system, no matter the circumstances). I tapped it back in at that time, but I guess it was crooked or damaged.
Luckily, this particular plug is the easiest one to access on the entire block - between the starter and injection pump on the driver's (or left) side of the engine. Determining what size plug to get was the most time-consuming part of replacing it - while the plug is the most accessible, access isn't all that great, and I couldn't get any sort of measuring device close enough to get a reading. I tried to order the plugs from the stock gas engine block, but they were too small. I finally found a website with parts diagrams of the block (see here) and was able to determine that the large plugs are 45mm in diameter. Of course, no local parts houses had a plug this size.
Mr. Lemond, Isuzu parts guru, sent me a stock Trooper diesel plug (C223 engine from '86-'87 also has 45mm plugs) as well as a block heater made for this size opening. I was able to install the block heater by carefully choosing the angle of installation (the plug is behind the oil pressure sender and the fit is tight - the electrical connector has to be at about 1 or 2 o'clock to clear it). I also had to remove the oil pressure sender in order to access the area, and tapped the block heater in by using long socket extensions inserted through the fender skirts in the driver's side wheel well. Once it was tapped in (to seat the o-ring), I tightened it from the same wheel well location.
Installing the oil pressure sender was tricky. I had to trim a small amount of rubber off the end of the heater's electrical cord to gain some additional clearance. I then inserted the cord, and spent a great deal of time trying to get the sender's threads started, as it was rubbing on the electrical cord connector. Once it was started, it went in smoothly, and there may even be a hair's breadth clearance between the cord and the body of the sender.
On balance, I am glad the plug fell out, as it gave me an excuse to install a block heater, something I have been meaning to do for some time. I am glad there was no damage to the engine when the coolant was lost. I've driven it a bit since then and all seems well - must be the cool-running diesel and overall ruggedness of the 4JB1-T that saved me.
