I just finished installing a new street port engine from pineapple racing and upon first start up it began to overheat. Luckily I caught it before it got past 220 but the temperature shot up extremely fast. I flushed the coolant and oil and started again and the same thing happened, however, I noticed the second time around that the heater was not blowing heat and the radiator was cold to the touch. If anyone has had a similar experience any help you could give would be much appreciated. I would rather not take apart my entire coolant system if one part is likely to be the cause of the trouble, and even if I did take the whole thing apart there is a chance I would overlook the problem. The thermostat is new and installed by pineapple racing and the radiator is new from a SII (My car is a 2007 MT, 115,000 miles). Any help or advice would be much appreciated.... I can't express how anxious I am to drive this damn thing!

 

You either have a really big air bubble or a complete clog in one of the main passages. My money is on the former.

My 8 was easy to bleed the one time I did it, but I had a nissan 240 that was an absolute c*nt to do, even with a factory, BUILT IN bleeder valve in the 'stat housing. The only way I could do it was park the **** on a steep upward slope, pop the rad cap and the bleeder valve, and add coolant while the engine was running, until it started coming out of both. Then the next time I drove the car I made sure to have a bit of 50-50 in the trunk just in case...

 

Have you called Rob? And have you made any changes to the cooling hoses? Are the stock brass restrictors still in the hoses if you did make changes? Are you sure the coolant hoses are hooked up correctly?

And dumb question but, were your fans working?

 

sounds like the thermostat isn't opening

 

but wouldn't the heater blow hot even if the stat was stuck?

 

Ok update, I have emailed rob but havent heard back yet... no bodifications were made to the coolant hoses, I dont know much about restictors but if they are there form the factory they are there now. Fans are working, and I have a box fan pointed at the radiator just in case. I started it again today and tried to bleed the coolant incase of any air bubbles but at 190 the coolant level didnt budge. I tried to unhook the hose on top the throttle body as ive heard that once coolant flows out there the system should be bleed but coolant flowed ou continously and even with that flow no more capacity was made in the overflow tank. Right now the car will only take aroud 5 liters of coolant.

 

My first thought was the thermostat too but you would think a fresh rebuild would include a propperly seated thermostat.... right? I replaced the Tstat on my own maybe 6 months ago and it worked fine before I pulled the motor.

 

I have heard of some t-stats being DOA's but, is the t-stat currently is the one you replaced 6 months back or did you get another new one during rebuild? Did you by any chance get a chance to touch the upper rad hose to see if it was getting hot at all?

Some reference that may help you along in the diagnosis:
https://www.rx8club.com/series-i-tec...iagram-183083/

 

My Pineapple built engine did not come with a thermostat, I'm not sure why yours would.

 

You mean you only put in 5 L total..? I don't have the spec in front of me but I thought it took 10 L. I remember when I did my rebuild I bought a 4L jug of D.I. water, a 4L jug of concentrated coolant, and knew that wouldn't be quite enough so I got a third jug of premixed. Poured the first two in and topped it off with the premixed.

 

Yea it took 5L total the first time I filled it up. The motor came with a thermostat because I shipped it out with the thermostat housing and thermostat on the block. I decided to check the thermostat to eliminate the variable and while it turned out to be in working order I filled the engine block with coolant from the Tstat housing, hoping this would mitigate air bubbles if that was my problem. Started it up this morning and it didn't overheat! Thanks for the help!

 

Yeah it was probably just a bubble in the system.