1G DSM Turbo replacement
My Eagle Talon was showing extreme oil consumption. I noticed that it was worse when I used the boost a lot. I also noticed that on high boost there was a black or blue cloud out the exhaust. The members of DSMTuners forum helped me confirm these were symptoms of a blown turbo seal.
I began trying to figure out which turbo I had. I bought this car used and the previous owner had mentioned the turbo had been modified. However, the turbo had the original marking ground off and some new numbers stamped in their place. I was not able to match these numbers to anything. Once I removed the turbo and disassembled it, it measured the same as a 16G. The stock turbo was a 14b on this car.
My original plan was to put new seals in my turbo. However, one I go tit off the car, I found the hot side housing was severely cracked and pitted. The turbine wheel was also cracked and missing parts of the blades. I am surprised it worked at all.
I found a true Mitsubishi 16G was very hard to come by. So, I decided to take a chance on a cheap eBay knockoff. It came with an installation kit and what appeared to be all the parts I needed. It arrived quickly and I set to work.
I used the procedure from http://vfaq.com/mods/turbo-swap.html to remove the turbo. One addition I have to make is that I had to remove the overflow bottle to get the radiator in and out. This step is not mentioned in the procedure. The idea of leaving the water line attached to the engine worked well. However I had trouble with the oil return line and ended up removing it contrary to the procedure.
Things were going well once I got over the idea that you really have to remove a lot of parts just to get to the turbo. A good pair of hose clamp pliers really helped with all the spring clamps.
I go the turbo bolted to the manifold easily. The kit came with new bolts so I did not have to worry with the stud. I had left the manifold in place like the procedure suggests. I learned the right rotation to bet the turbo in over the water pipe and under the manifold.
My first problem came when I realized I should have installed the oil feed line before mounting the turbo. There was simply not enough room to twist the line in behind the turbo to get it to the fitting. I also noticed that the clip seemed to be on the line backwards. I spread it apart and turned it over. I pulled the turbo back off the manifold and slipped the line in behind the turbo. I then popped out the plastic plug in the top of the turbo and noticed a huge problem. The hole in the turbo was too small for the banjo bolt!
I checked and found it was the right size for the other end of the oil line 10mm not the 12mm that is supposed to be on the turbo end. I tired to think of ways to work around the problem. The only solution I had at my disposal that day was to drill and retap the hole.
I pulled the turbo back off and set up to drill out the hole and retap it to the correct threads. When I got done, I found that my tap would not reach deep enough to thread the bottom of the hole. I needed a bottoming tap that I did not have. I compensated by grinding off the end of the banjo bolt so that it would go in far enough to crush the washers. Only after reassembling everything did I find I had cut too much off the bolt.
I had to pull the turbo back off and order a bottoming tap from McMaster Carr. With the new tap I was able to thread all the way to the bottom of the hole and with a new banjo bolt it screwed in the correct distance. I then put it all back together on the car.
I had a very hard time getting the oil return line back on. The original tube would not pull back up to the turbo after I bent it down to get the turbo out. And the new line was made slightly wrong so theta it did not line up well with the pan. There was a slight twist in the flange. I was able to get the flange to line up by using a pry bar to twist the flange while I started the bolts. I had to remove the down pipe to get enough room to do this however.
When I started the engine there was a huge oil leak at the oil fitting on top of the turbo. I tired new and old crush washers but they all leaked. I even swapped back in the old oil feed line thinking something must be wrong with the new one. I read about annealing crush washers so I tried that. They all leaked.
After buying two more new washers, I carefully examined the pattern on the washers and I noticed there was not full contact all the way around the washer. It was apparent that I had not drilled or tapped the hole straight when I made it bigger. I researched several options and eventually decided to try some nylon washers. The trouble was, the ones I bought had mold marks on them that I did not thing would allow them to seal. I had to sand them smooth before installing them.
The nylon washers sealed. However, now the top of the oil feed line leaked at the head. I removed the bolt to install new washers and I noticed that there was aluminum in the threads. As I suspected, when I tried to retighten it, the threads in the head stripped.
Upon careful inspection, I found that the reason it stripped was that the new banjo bolt in the kit did not have the correct thread pitch. The DSM head is 10mm x 1.25. The new bolt was 10mm x 1.5. Since 10mm x 1.25 is hard to come by, I decided to put in a 1.5 pitch helicoil.
I removed the air box and other items that were in the way of getting the drill in the engine compartment. I pulled the Allen head plug in the front of the head and stuffed in some Q tips to try to limit metal shaving going into the head. I drilled out the hole and then carefully tapped the new threads using the special helicoil tap. I was very careful to make sure it was all straight. I wiped it clean with Q tips and brake cleaner. I then spun the engine over to pump some oil out to flush out the metal shavings.
Once the insert was in place, I was able to bolt up the oil feed line and put it all back together again. This time it all sealed! It took a while to burn of all the oil that had spilled from all the failed attempts.
On the first test drive, I was surprised at how fast the boost came up. Boost comes in much earlier compared to the old worn turbo. I did not make it far done the road before I heard a terrifying noise an the engine died. I coasted to a stop and began looking under the hood. It took me quite a while to notice that the hose had popped off the turbo outlet. Once I put it back, then engine still would not start. I then realized I could not hear the fuel pump running.
I accessed my hidden fuel pump override switch and the engine started right up. After I got it back to the shop and shut it off, the fuel pump operation returned to normal.
The only reaming issue was the temperature gage was not working. I did not realized there were three temperature sensors o the 1G motor. I had made sure the two wires were in place but the sensor for the temp gage is hard to see under the blow off hose. Once I removed the hose and looked, I saw the wire had gotten knocked off. I simply reconnected it and the gage came back to life.
Hopefully this turbo will continue to work well for me. I did some research on the internet and I believe that this turbo was supposed to be for a Subaru and not a DSM. That is why the oil line seemed backwards and the fitting was wrong. I reread the ebay listing and noticed it did not say it was for a DSM. It simply read for “custom applications.”
Dong this project, I added another tap to my collection; I learned how to anneal copper washers and installed my first helicoil. I also learned how to be more patient with removing parts to get to others on the cramped engine compartment of the Talon. I also remembered how much fun this car is to drive.