Why does the new engine run so hot?
 

it goes to 250 degees in 70 degree weather, do I need a bigger radiator?

Why so hot
 

Clean the old one. Usually lots of leaves between the A/C condenser and the radiator. But the real problem is the small dirt and debris in the fins of the radiator. You can't see it until the radiator is out. If you have deep pockets, just replace the radiator as removal and install are the same as a thorough cleaning.

Is there a way to see the leaves? how do they get in there? The AC condenser is preventing the leaves from going in, like an air filter :)


what is the step by step( sorry) procedure to remove and replace the radiator? thanks...

Bottom feeder
 

Get under the front end and look up in front of the black plastic air dam between the condenser and the radiator. You'll probably see a leaf or two or LOTS. If there's a Walmart plastic bag, that's the problem.
Removing the radiator is a pain because the shrouds have to come off. Teeeeeny screws that are even more difficult to install than they were to get out. I haven't had to do mine but reading about it (see the 'search' tab above for radiator cleaning) sounds tough.
I have blown out many radiators' air side with compressed air and found it really helped the cooling. For the water side, there is a good radiator shop in Newark, DE, that I use. He also does very nice radiator and A/C repair.

i've done radiator removals before, they are a PITA! :ack: but doable if you're patient and if you have the time and the right tools. the shroud definitely has to come off. there are (if memory serves correctly) 3 or 4 little screws down sides of the shroud and along the top back of the shroud holding it all together. there isn't much room in there for any kind of tool, so you would have to use either a 1/4" rachet or an open-end wrench to get the job done. the intake tube also has to come off, but the air filter and air box can stay on. they don't get in the way. then it's just a matter of pulling it off slowly and carefully. getting it back together is a little bit of a PITA also because there are 2 rubber alignment bumpers at the top of the shroud that hold the radiator and the A/C condenser core in place. it's time consuming, but doable... hope this helps... :thumbs:

Also, since you put the new engine in, did you burp the system? You may have an air pocket. I went through this headache on the last rebuild I did.

Thanks I'll try that, It seemed to have cooled down to 225-230.
oerhaps the engine was new and tight?

I just replaced my radiator this weekend (85). It cost $130 at a local car parts store and took a few hours. I have never done a radiator change before and I am still a beginning mechanic and I didnt find it very hard. It helps alot to have someone else with you when it comes to moving the radiators around. I also replaced the radiator hoses at the same time. Replacing the bottom radiator hose was the hardest part of the entire install.

Thanks that's encouraging, was the debris and leaves in between the radiator?

I removed my radiator, and changed the upper and lower hoses. There was a ton of plant seeds stuck between the fins on the radiator. The air conditiooning condenser was dirty as well. i used a hose and a spray nozzle, but had to "bang" the radiator on the concrete driveway to loosen the seeds.Then I washed it out better, and got ,032 wire and poked out the stubborn ones.
It took most of the day to remove, and clean and do the hoses,
Do not use compressed air, as the high pressure air bends the fins over and stops all airflow altogether.

There was quite a bit of sludge and leaves. They were mostly under the radiator but it is hard to tell if that was the case or if they fell off when I was taking the radiator off. I live in Albuquerque and nothing grows here, so I am sure you live will have a lot more leaves then what I had.

Not sure if it matters but my car has 123k miles on it.

One more thing that I just remembered. The transmission on mine (4+3) uses the radiator for cooling so I lost some trans fluid in the change. You will want to have some fluid on hand so that you can top off the trans when you are done.

manual transmissions do not use the radiator for cooling. Are you sure its not an auto?

I just made a smaller attachment for my shop vac and ran it through the hole in the shroud where the tranny lines go in on my 95 .
Got the big stuff but I'm sure when temps go up I will have to pull it and do a good job anyway. :thumbs:

I just had my 96 taken to the shop 2 weeks ago for running hot. During the mechanics investigation, we discovered a small bird nest LOL. I just bought the car 2 months ago, and the temperatures were still mild which explains why I have not seen increases in water temperature.

In my case, I decided to have the entire system flushed, new radiator and hoses. Even after all this, it still runs on the hot side since the fan(s) don't come on until 220°F or so. My car pool buddy has a Trans-Am, and he was thinking about adding this:
http://www.jegs.com/i/JET/561/60600/10002/-1
Do they have something comparable for the Vet, or would it be easier to change the setting in the computer module? I hate the idea of the car running this hot, especially where I live in the desert.

I think they can change the temp constant in the memcal/prom, to start lower and stop lower., that is a pain too.

From what i've heard those switches aren't the best method. Depending on what thermostat (anything above 160*) you have the fans will probably never turn off and you'll burn out a fan motor alot faster. The fans are set to turn on a 227* which is normal for an LTx.

I'm not the most familiar but I think you can change fan on/off settings by tuning the car and changing the parameters of the fans on/off cycle.
Im thinking (for your location) a 190* tstat and the fans on at 220* and off at 200*. Your temps are normal but scary to some who don't know the LTx. You still want enough heat to evaporate the water vapor, etc. in the engine. But I feel your concern living near the gates of hell..lol

Good Luck...

Fred

How did i not see slick's response? :o Oh well I just said it again with a little other info.

Hehe...gates of hell is close unless you live in Death Valley in CA or in Laughlin Nevada. My wife and I made a trip there a few years back, and when we opened the door, the temp outside was 122°F in the shade. The guy that took our car to park it said, "it will cool down by midnight to 95°F."

I guess after these years of having cars with a stupid gauge that does not really indicate the exact temperature. The one in my Ford 2001 F150 Crew Cab does not have any numbers on the dial. Only cold and hot marks at the extremes. Hell, for all I know, it probably runs at the same temperature, but because I can't measure the exact temperature via the gauge, I really don't care since it rides in the middle of the gauge all day long. Even the wife's Honda Accord is the same with a similar type of gauge.

After reading all these "hot" threads, I guess I'm going to leave it alone for now, knowing that it will be very important to make sure you have the right mixture of anti-freeze; otherwise, you risk a boil over of the cooling system.