Rare overheating!?!?!?!

[Caboobaroo]

So car is an '87 EA82 SPFI coupe, FWD 3AT -> RX FT4WD swap. Engine is stock EA82 SPFI (and I mean totally stock, even has the stock intake piping in the fender). When I lived in Laramie, it started to get a bit warmer after driving it for a few minutes, then blew an upper radiator hose. Fixed that and was fine since. Coming home from WCSS9, I noticed a little bit of pinging before I pulled over to get gas. Noticed after getting off the freeway, it was boiling coolant out of the overflow. Let it sit for a few minutes after getting gas and got back onto the freeway, with the heater on. Haven't had a problem since. I'm leaning to a bad radiator cap but I'm unsure of it. I have a brand new 2 row radiator, dual electric fans, and a brand new STi radiator cap. Sound like a logical problem?

[nipper]

For the cost of a cap (Shame on you for not replacing it with the Radiator ) i would try that first.

 

 

nipper

[daeron]

then thermostat.

 

Check your AC condensor and make sure it isnt obstructing airflow to the radiator.

[Gloyale]

I klnow you are a pro with these so I'm guessing you've checked. But if you are hearing pinging it may be you're timing is off. If it is you will have overheating even with a perfect cooling system.

[Caboobaroo]

Tming is spot on, right at 20 with my green connectors together (like the FSM says to). Radiator IN the car is the stock one but I have my other radiator in my garage with the fans and STi cap on it. Not really supposed to work on my car here so maybe I can convince Ed to let me borrow some driveway space for a few minutes.

 

Just to let you guys know, I've put about 1500 miles on this swap and like I said, this is the second time this has happened to me. Got no bubbles in the radiator so headgaskets are still good. I get paid tomorrow and I'm going to be getting some more parts for my car (timing belt tensioners, Seafoam, fluids, t-stat) so maybe I can swap in my new radiator this weekend as well.

 

Also, how much would the STi pink radiator cap effect my cooling system?

[Jerry DeMoss]

Also, how much would the STi pink radiator cap effect my cooling system?

 

I think it could make a pretty big difference. Although I think the problem may lie in the fact that Jeff is hiding under your car somewhere!

 

I think thermostat and radiator cap will fix the problem.

[idosubaru]

make sure the fans are coming on properly? they're blowing the proper way too right, they're not wired backwards or anything and blowing in opposite directions? the radiator cap has to be the right pressure or something right? make sure that's right?

 

you're timing is off. If it is you will have overheating even with a perfect cooling system.

i've heard that, but i drove an XT6 for 10 months with the timing off by 8-10 degrees. it drove fine and i never bothered to check it. finally set it correctly and it made no difference?

[Gloyale]

 

i've heard that, but i drove an XT6 for 10 months with the timing off by 8-10 degrees. it drove fine and i never bothered to check it. finally set it correctly and it made no difference?

 

Where you advanced or retarded?(and I'm not talking about your schooling)

Did you try and climb any 5 mile long grades up over 8000 ft passes? If you had you may have run into trouble. Also, you may have been right on the edge of what can work. And with an XT6 there is a knock sensor and other inputs that help the ECU control timing. SPFI=no knock sensor, and Carbed is even worse because there is no ECU control over ignition at all

[mikeshoup]

I ran my old SPFI setup at around 27 degrees. No trouble at all on 85 octane. (bear in mind, I do live at a mile high) This was including numerous trips into the mountains at pretty high elevations (drove to the base of a 14er at ~11,000 feet).