My 1990 300zx Twin Turbo build by megaDan

10 minute(s) of a 731 minute read

Sorry, way past due on thread update.

I'll try not to rehash too much. We got all packed Thursday night, took a half day Friday so we could enjoy the day and drive, filled the car at noon on Friday and took off. More than enough room for a full weekend of gear (plus woofer box) for two people! The cargo area is surprisingly big. We even had the tops off for a bit, stored on top of this pile of stuff.

Two duffel bags, a big backpack, an emergency tool bag, and normal wife stuff

I figured a mid September road trip would be the perfect time for a road trip since the AC is still inoperable. Wrong. It ended up being low to mid 80's and sunny all weekend. Beautiful weather, but just barely on the wrong side of uncomfortable in the car. We drove most of the way with the windows cracked or down. Given that we weren't in a hurry, I kept the speed down more than I normally would so it was still a relaxing drive, even for a 4 month pregnant wife with no AC. She's a trooper First stop was a little earlier than planned but not a big deal. Wife ran into the bathroom, I took a picture of the car...for the archives.

Why's it wet?

Sent it to my buddies and said, 'don't worry, that water isn't from me'. Then I started to question myself so I went over there to check it out. Turns out it wasn't from me, but this is where I discovered the coolant leak by way of the steaming on the exhaust. Based on the very small puddle on the ground and the fact that the day was cooling off, I elected to pick up some water at our next stop, and take it easy on the fun pedal and continue on. We're about halfway to our final destination at this point.

Day 1 map

Knowing I only get around 220 miles per tank via highway driving, I planned possible fuel stops ahead of time, so I could maximize time on the road and reduce chances of needing to swap to 93. Finding a station wasn't hard, thanks to an abundance of E85 in Wisconsin. If the government does one thing right, its help those in need find E85. Check out this handy website here. I even found an app version on the play store.  If a station has it in Wisconsin, its generally a dedicated pump, but well marked and easy to find. I found that in Minnesota there are some stations that have it available at every pump, as a 4th fuel option. Very nice! This probably makes dealing with E85 only sound like a lot of work. It's not. After the first week of driving with the conversion, I had all the locations within 30 minutes of my house memorized. I generally don't need to alter my route to add a fuel-up to an errand or trip. We stopped as planned just before Eau Clare for fuel and a gallon of filtered water.

Not a problem finding fuel


We continued on to our destination and my wife found a place for dinner on the border of Wisconsin and Minnesota along what we thought was the Mississippi. Turns out the Mississippi doesn't become the border until 30 miles or so further south. Anyway, we stopped at Pier 500 in Hudson just as the sun was setting. The weather was beautiful, the view from the restaurant was beautiful, the food was pretty good and the service was meh. Still a wonderful evening, and we took a walk out into the river while we digested. At this point we only had 30 minutes or so left on the drive and the sun was down so we elected to cruise the rest of the way in style....topless. Found that we had plenty of room in the hatch to securely store the T-tops along with all of our belongings. I did a poor job of taking pictures most of this trip. I apologize.

The rest of this day's journey was uneventful and we arrived at the hotel mostly unscathed. I dropped my wife off to check in and I parked the car. As soon as I got out I heard more steaming and my heart sank. Without knowing the cause of the problem, I really hoped that the cooler temperatures would have prevented the coolant leak. The fact that it didn't told me I definitely had a problem on my hands. This shouldn't surprise any of you, but thanks to the somewhat tight engine bay it was very difficult to spot the source of the leak. I poked around for 15 minutes or so with no luck; using my phone with flashlight and video mode on as an inspection mirror; sticking it where I couldn't reach with my head or see with my eyes. I could tell the general direction where it was coming from, but I couldn't spot the source of the leak. The location was very close to the drivers side turbo, so I figured I would tighten all the coolant line hose clamps and banjo bolt fittings. Given that I've found so many things work themselves loose with the temperature changes it wasn't terribly surprising (aside from the fact that the cooling system has been solid for years).

Thankfully she had some work to do, so I wasn't ruining our weekend away yet. I got my wife her luggage and let her get settled into the hotel room while I found a street light to park under and got disassembling. See the section highlighted in green below. The turbo outlet piping was in the way, so it had to be removed.

Just gotta remove this. In a parking lot. In the dark. With hand tools. Simple!


I figured this (below) was the culprit because of both the location, and the telltale staining where the hose clamp was attached. I got the piping removed, got the hose clamp off thanks to my long reach needle nose pliers, and got the hose off the fitting.

This picture is AFTER the piping was removed. Still tough to get to.

A little closer......

I noticed that the hose was a little dry rotted, probably thanks to being sandwiched between the exhaust manifolds and the turbo. I cut off the last few inches of the end of the hose, reattached it, reassembled the intake piping, checked my watch to see I'd only been at it 45 minutes or so, and went for a test drive.....

...and was not very shortly met with disappointment. I got it up to temp as quickly as I could (optimism is great for warming up engines) and stopped at a gas station for pregnant wife cravings. As soon as I got out of the car I was deflated, as it seemed to be pissing coolant more so than before. This was the first time I had a twinge of doubt as to whether or not the rest of the trip would go smoothly. Still just a twinge at this point, as I have confidence in my abilities; but doubt as to whether or not I was going to be able to fix what the issue was (once I eventually found it, which I also had confidence in).

I got it back to the hotel, delivered the fun size oreo treats, put my emergency cranberita in the fridge, and got back to work in the parking lot. I had been trying to limit the amount of disassembly needed for the fix for what should be obvious reasons: I've got limited tools, I'm in a hotel parking lot at night, and I'm 400 miles from home. But with my first repair being unsuccessful; I decided to go for broke. I knew the leak was coming from the rear half of the drivers side of the engine; so I was determined to get as much visibility to that area as possible. With the engine still hot I quickly took off the balance tube, removed the wiring harness in that area, and got the intake pipes back off. Shortly after I found what I was looking for. Hooray!

Imgur's image scaler doesn't work on gifs, you'll have to click the image to see the fun. Sorry

This is where I pretty much called it a night. This is the same hose that I had shortened on the turbo a half hour earlier, but the leak was at the area the hose rounded the block. I wasn't sure where the hose terminated at the other end, but some internet searching would help with that.

At this point I was able to mostly relax and formulate my plan for the next morning. Our first game wasn't until 10:30, which means we didn't need to be at the fields until 9:30. Autozone opened at 7:30 which gave me about an hour to get this fixed. Easy! I was up by 5:30 or so, got a workout in, grabbed a cup of coffee, and walked to the Menard's next door at 6:30ish. It was a surprisingly serene experience, and I've never felt like more of an old man. Coffee in hand, pretty much the only customer in the store. I was there to purchase hose clamps and brass unions, in the event that I couldn't reach the other end of the leaking hose. I would cut it back as far as I could, and replace the end I could reach with new line. I got breakfast, posted an update, and hit up autozone for fuel injection hose. Once I got the hood popped again I realized immediately that replacing the entire length of hose would be no problem. I removed the old hose and set it aside. I immediately realized I needed to document what was going on, so when I went to snap a picture I saw that the hose had cracked in half. From the force of me gently setting it down. That's how cooked it was.  

Sweet jesus


I replaced the hose and was done in 20 minutes or so; got back to the hotel room to get cleaned up, and we made it to the fields early. It had rained all night, and was projected to rain all day. Thankfully I caught a break during the 30 minutes or so I was outside fixing the car. I wasn't able to thoroughly throttle it on the way to the fields, but I felt confident in my fix and was ready for a long weekend. Yay!