Stillen S.C. Plenum charge assembly coolant leak during WOT on dyno
 

I purchased a VQ35HR stillen supercharger kit for my 07 Nismo from a forum member over at my350z. Since the stillen s.c. is more popular for the VQ37, i figured this would be the spot to post.

Before i begin, I am well aware about the consequences with purchasing any used forced induction kit. Kits get passed around. I contacted the seller before and everything seemed legit. So please, heard it from everyone already. "Should have got a new kit".

I personally installed the kit and upgraded to the larger heat exchanger from frozenboost. Type 101. The blower was inspected and was in good order. I replaced the bearings in all the pulley's, new belts, ect... I brought it over to Kaizen tunning in Boxboro Ma. They have great experience with Nissans, lots of GTR work is done there, 370's, ect... They boost leak, vac leaked, everything checked out.

When it came to the dyno, the car put only 320wHP at 6.5 PSI and was showing some AFR issues. Then a cloud of white smoke at the end of WOT came out. Entire pit was a rock concert. Suspecting a charge cooler leak, we took the 4 bolts out of which the charge cooler was assembled in the plenum. Slid it out and there was coolant in the plenum. I am stuck now having them pull the top end out and inspect the sleeves and doing a compression and leak down test. We couldn't pull the entire core out because it was hitting the timing chain cover.

Has anyone experienced a coolant leak from the plenum assembly? Hopefully the motor isn't toast. After the dyno, we let the car idle and it was fine. Still for reassurance, i'm going through the inspection. I can understand any wear and tear from all the components... but this charge cooler in the plenum has me scratching my head. It was well packaged upon receiving. No scratches or any evidence of damage during shipping.

All help is greatly appreciated. Any chance Stillen could shine in?

-NT

Well, the good news is there are probably 40 plenum coolers sitting in people's garages on this forum.

Haha, TopgunZ. I believe you or another member released the air to air set up?

Edit... It's In your profile description. My next stage for next year was upgrading to your kit. It's a work of art I must say.

Anyone have a Charge cooler they want to sell? My Z is sitting at the tuning shop and I need a replacement ;-)

Anyone know if there are seals in the core cooler that could fail? I can imagine the 2 90* elbows leaking. What about the plate? Is there an o-ring?

If your looking for a cooler I would post in the for sale/ wanting to buy section of this forum you would probably have much better luck.

There is a zero-miles unit at my shop that belongs to a customer who wanted the a/a kit done with original install. I could pack and ship it on his behalf as soon as tomorrow. I'll point him here to see if he wants to sell it.

Sweet. Much appreciated

At idle, there was no white smoke at all. It makes me believe if there is a leak, it is small. The reason for the white smoke at the end of WOT is the blower is producing 6.5 lbs which was also pressuring the independent closed loop cooling system for the plenum through this leak. When the Z went into vacuum, the now pressurized plenum cooler then discharged coolant at about 6 or so psi. Hopefully I'm not screwed. Like I mentioned, car ran fine afterwards. Curious if anyone ran into a similar issue and could shine in whether or not I hydro phucked my engine.

Why don't you disconnect the water lines to the plenum cooler, drain it, seal one side, then blow air into the other? You will find out if there is a leak.

We know there is for sure a leak. I slid the cooler assembly from the plenum and there was coolant everywhere.

He said he is willing to let it go. I will PM you when I hear back from him on how much he is looking for.

Great news. Much appreciated. Still nothing from Kaizens. They are booked this week and will only be able to pull the entire assembly if there is a cancellation or the following week. I'm crossing my fingers with the compression and leak down test results

How much coolant you have left in the Stillen system? Depending on the water pump pressure, size of the leak. You might have gotten lucky and did water injection. Cleaning the combustion chambers and the tops of the pistons. If the motor kept running. You should be ok. It didn't hydro-lock. That's BAD!

Used to take a water hose and spray it down a carb until water started to run out of the tail pipe of a running motor. Never hurt it either. :rofl2:

I believe that is what happened. The car was running fine after some idle after the pull. The reservoir was not completely empty. They run a tight shop, so the upcoming tests are essentially manditory. The nismo is an 07 with 53k miles. I probably should have done a compression and leak down before the install... So no harm at this point. Thanks again for the help

-NT