Question Re: Radiator Size

Q&A regarding engines, turbos, and intercoolers and power upgrades

Question Re: Radiator Size

Postby CodingParadox » Tue Oct 05, 2004 1:48 am

So, it's been brought to my attention that possibly my aftermarket radiator replacement (which came with the car when i bought it, i didn't put it on) is far too small compared to the usual ST165 radiator. This would explain why I'm getting really weird overheating issues.

So does anyone know what the size of the usual radiator is? The radiator in my ST165 looks about the same size as the one from my ST162 (89 GT) though it's aftermarket, so a different style.

I'm pretty desperately trying to track down this overheating problem at this point. I replaced the thermostat and that helped somewhat, but after my 4th run at rally-cross my engine jumped into the redline for heat for about 5 seconds before coming back down.
Members don't see the above ad. Register now - it's free!
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:12 am

Into red? AH!! bad bad bad.. :(

Have you check for a bad head gasket at this point?

Are your fans coming on?

Did you flush the cooling system to make sure there was no air in it?
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby CodingParadox » Tue Oct 05, 2004 6:15 am

I haven't torn apart my head, no. But I've checked oil, no water in it. Compression check reveals going seals, but it's perfectly even all across, so doesn't seem like a bad head gasket.

My fans are always on. It's a stupid aftermarket rad without a temp sensor, so the fans stay on.

I've flushed the coolant system like 4 times now.

I changed the thermostat on saturday, which made it a little better, but I'm still getting the spikes. Sigh.
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:15 am

Post some pics of your radiator.. I'm sure someone with a 165 can compare.

In the meantime, go look under your oil cap. If there is a milky film. That's water in your oil. Also check your dip stick for the same stuff.

Hitting the red on the water temp gauge is Extremely dangerous!

That's waaaay too high.. :( cool it down with normal driving when it gets to about 3/4 of the way.. Which, depending on who you ask.. is still too hot.. :( This sucks man....
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby CodingParadox » Tue Oct 05, 2004 6:17 am

You can kinda see what the rad looks like here:

Image

No milky white films anywhere.

The temp shoots up. Like, literally, it'll be slightly left of center like normal, I'll boost up to 45 from a stop or so then be cruising for a second, then 5 seconds after I'm just cruising, the temp gauge will shoot up to redline from the midline in under 5 seconds. It's not like it's a slow overheat that I can control or stop. If I keep driving, it jumps back down again.

Someone mentioned my temp sensor might be fucked, so I'm contemplating trying the one off my GT and seeing if I get the same result...
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby CodingParadox » Tue Oct 05, 2004 6:19 am

And also, it's not an always thing. When driving out to hood river yesterday morning, I capped out 10psi boost for like 30 seconds accelerating to 120 on the freeway (yes I'm a moron, but it was a complete straightaway with no cars whatsoever, and guaranteed no cops, and in an alltrac it doesn't take long to get to 120.) I'm sure I was knocking like a bitch, but the temp only barely went up (teensy bit right of midline.) Then, after 3 runs of almost no temp raise at rally-x, at the end of the fourth run, after pulling up to the finish line, as I was going back to park, it shot up to red then right back down again...
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:20 am

Yeah your temp sensor is fecked. ;)

Does it seem like a elec. glitch?
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby CodingParadox » Tue Oct 05, 2004 6:23 am

It's hard to tell. When I first got the car, it _was_ actually getting too hot. But that was because I was low on coolant and didn't realize it. Air bubbles in the system, etc.

But I flushed the coolant a number of times and since then, it's just been warm but not too hot. Like, after driving around real hard, if I immediately open the rad cap I'll get a fair bit of boiling coolant all over the place, but that's not exactly surprising.

When I'm talking about these redline circumstances recently, there's no overflowing into the overflow bins or anything, the gauge just shoots up and back down again, leaving me pooing in my seat.

So that does sound like a broken temp sensor rather than actual overheating?
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:24 am

Yes, sounds like bad sensor.
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby illGT4 » Tue Oct 05, 2004 6:25 am

Or trapped air.

Never open a rad cap if it is up to temp. .You can burn yourself..
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby CodingParadox » Tue Oct 05, 2004 6:25 am

It's hard to tell if it's an elec glitch or what. I don't know how fast engines are capable of heating up. Boosting seems to be fairly hard on an engine, and so it'd seem to me that without adequate cooling, a few seconds of hard boosting would be enough to really raise water temps if something was really fucked. But the fact that my temp gauge can shoot from midline to redline and back again, whole cycle taking under 15 seconds, seems a bit odd to me.

Also, on the trip back from hood river, I was cruising at 90 most of the time. If I was cruising at 65 or so (3400RPM-ish,) temp sensor would stay slightly left of center like if I were idling. Cruising at 80, brought it to midline-ish, cruising at 90, slightly right of midline. I don't know if this is normal behavior or what.
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:28 am

No I wouldn't say that's normal behavior. Def. get things checked out.

The temp gauge should stay at the middle or slightly under.

Going up and down like that (if taking 15seconds to do so) is either a bad head gasket or air in the system.

Not something to be taken lightly, either way. :(

Boost or no boost it should stay put. Not move.
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby CodingParadox » Tue Oct 05, 2004 6:28 am

There's a towel in the back of my car that I've been using to open the rad cap. So it has a fair dose of coolant on it. Mmm.

Okay, so when I flush the system, all I've been doing is flushing the rad completely empty with the drain plug then refilling it. However, I noticed, when I replaced the thermostat, that there was still coolant in the engine, that I guess didn't come out due to gravity through the rad. Is there another drain I'm supposed to be emptying from too? Is it possible that even though I've flushed the entire rad system 4-5 times, that I still have an air bubble in the engine somehow due to me not draining that part too...?

Possibly unrelated - the heater in my car barely works. When I first got it, it wouldn't heat at _all_. More recently, the air takes on a hint of warmth when I turn the temp control all the way up, but still not very good. However, the heater lines going back from the engine into the firewall are warm all the way up to the firewall (by warm I mean hot.) So I'm not sure what the hell's causing that.
David - Former owner of multiple Alltracs. Have moved on to yellower fields...
Image
User avatar
CodingParadox
Established Member
 
Posts: 1735
Joined: Sun Aug 15, 2004 7:50 am
Location: Bellevue, WA

Postby illGT4 » Tue Oct 05, 2004 6:44 am

If you didn't flush it correctly, and adding fluid back into it slowly.. good chances you have air in the system.
Imagewww.illtuned.com

- Professional Motor Sports Driver & Instructor
- Vehicle Dynamics Specialist
- I4WDTA 4x4 Certified Trainer

User avatar
illGT4
Established Member
 
Posts: 1820
Joined: Mon Aug 09, 2004 3:39 am
Location: New Castle PA

Postby T-spoon » Tue Oct 05, 2004 11:26 pm

I just finished with a long drawn out nightmare overheating problem with my '90 that I sold last week. I had replaced temp sensor and thermostat. A hose burst from the heater core, replaced that. Finally got to a friend that had a proper tool and found that between one core and the next on the aftermarket rad the first owner installed, the temp would jump at least 20 degrees. That suggests blockage, so I replaced the rad, and after another hose or two popped and replaced, it doesn't overheat anymore. It's definitely possible for the radiator to be too small or clogged which will cause you to overheat when stressed. My 90 wouldn't overheat sitting at idle indefinitely, but once you boosted or drove for a while, it would because it wasn't getting good circulation.

Oh, and definitely when you refill coolant, leave the cap off and let the car run for a bit with the heater on full blast. You may also need to squeeze on the upper radiator hose as air likes to collect up there as well.
T-spoon
Club Member
 
Posts: 90
Joined: Sun Aug 08, 2004 6:16 pm
Location: Seattle


Return to Performance and Power

Who is online

Users browsing this forum: No registered users and 3 guests