Just buy a hose spring and put it in. They are cheap. Then even if that's not the problem, you'll know.

 

Good way to check is to just go in and squeeze the lower hose, if it is overly soft, that is the culprit. And usually you can see the bend in the hose where it has collapsed before.

 

The lower hose is new, but it doesn't have a spring. I ordered a spring...hopefully, a solution is close at hand.

 

Put a radiator hose coil in the lower hose and backflushed the rad(4th time) yesterday. Drove it on the highway for about 20 minutes(70-80mph).....overheated!. Drove it back home on back roads (under 50MPH)...no problem, temp gauge pegged in middle. I have never been so frustrated by a seemingly simple problem. I don't have any idea about what to try next. Do any of you?

 

I am going through the same exact thing. We never drove the car on the hwy and now its overheating too. I just bought a gates Part # 26502 lower hose. You can literally stand on this thing and it wont fold or kink. I also have a 3 row rad , hi flow pump, new heater core, I just replaced the engine (only 100 miles on it). The problem I think I might be having is either my lower hose is collapsing or my radiator is clogged. I did have a bad head gasket on the new engine and found some oil caked on the insde (top) of the radiator. I tried flushing it with formuala 88 degreaser but I didnt do it all that long. I might just have to take it to the rad shop and have them do there magic.

Ivan

 

How do you know that it is overheating. The factory temp gauge reading in the middle is about normal.

I would get an infarred thermometer to get a better idea how hot it really is. You could try using a meat thermometer and just let it sit in the coolant with the cap off while its running and see what it reads.

You can also do what I did and use a thermometer like this one and put it in the port in the T stat housing. To do this you will need to get some brass fittings to raise it up a little. You can use it for testing or leave it there like I did.

Then you can compare these readings to your gauge in the dash and you will be able to get a better idea what the different positions actually mean.

http://cgi.ebay.com/ebaymotors/Small...Q5fAccessories

 

In my case, I am using a digital gauge. I get an actual numerical value. That tstat thermo is really nice...

 

Have you tried a leakdown test on the cooling system?

I want to think that an internal leak would have showed up in other ways already but I don't know what else to recomend at theis point.

How has the coolant looked when you flushed the system? Was it black, or did it have black in it?

Are you running a stock fan?

 

This time the coolant isnt getting pushed out the radiator. Even though it is overheating on the hwy , All the coolant stays put. I had installed a clear inline coolant filter. And I am happy to say its is showing no bubbles what so ever. When I did flush it a 3 or 4 months ago, it had small globs of oil floating in the rad. Thats what urged me to run my finger inside the rad. Even the cap had goo on it. This time around the small globs are not floating and the coolant looks prestine. I am problably going with a new rad. I just read on another forum, a member going throught the same exact thing. He was overheating only driving past 50mph. He just removed and replaced his rad and is up and running he says. We will see. Give me a week or 2 and I will let you guys know.

 

My problem has been solved! After close inspection of the new radiator, I could see it was caked full of rust. Apparently, even after many flushes rust was still present in the block and eventually depositing in the new rad,not allowing for proper cooling at higher engine temps. I bought a new rad, but first backflushed the system with no radiator in place with prestone backflush kit for about 30 mins with engine running. Then installed a new(2nd one) radiator....drove on highway and temp stayed way below the mid point on gauge for over an hour. Wow, what a trip.