I bought a new high capacity solid aluminum radiator. Installed a like-new, but used A/C condenser. I have also installed a new water pump, thermostat (twice), new opti, and did a re-seal in my intake (china wall was leaking). Before all of this, I was seeing 205* to 210* temps. With the bigger (better?) radiator and after replacing the condenser with one that has no bent fins, should I not be seeing lower temps?? Im now seeing it creep up to 212* pretty consistently even at 75* outside temps @ 55 to 80 mph. The only thing else I did, was install some mechanics cloth (about 1/4" mesh) over the air inlet to help protect the radiator and condenser. Would this cut back enough airflow to make it heat up? I'm at a loss here. I absolutely, under no circumstances, should see an engine run that hot. No need for it. I understand reverse cooling, but I'm seeing cylinder head temps are consistent with the temps from the digital display.

One more confession to make... Under the advice and supervision of a GM tech, I thoroughly cleaned and flushed the cooling system (including the heater core) and refilled it with Dex Cool. I know a lot of folks don't like it, but the previous owner of the car severely neglected the cooling system, and I had quite a bit of corrosion. Something had to be done to stop the corrosion. Having said that, I'm confident that the cooling system is clean.

Anyone else able to solve their cooling problems??

 

Anybody ever install a radiator air inlet screen and notice higher temps?

 

don't now about yours, but I run a L-98 and that's an ok temp. The only other thing I can think of is the sending unit might be a tad off.

 

What year vette? '93?

Anything that restricts air flow will affect cooling. Don't know if your
cloth is restricting air flow.

If you are running an LT1, a specific tstat is required....you knew that.

When you cleaned/flushed the cooling system, did you remove the knock sensors (you may have 2) located in the bottom of the block?
Possible that debris built up over the years in that area and is restricting coolant flow..... guessing.

My stock '92 LT1 runs at 185 - 205.

Cooling requires coolant flow and air flow...... block one, or both, and you have overheating..............pretty simple.

 

Yes. It's a 93, LT1. I know that the new distributor certainly made the car run much much better to the point that it actually sounds different. It's definately making more power, therefore more heat.

Yes. When I did the flush, I removed both knock sensors. Actually, that was its second flush. I did one a short time ago and refilled it with a corrosion preventative and just water, so even the second flush, there was no old glycol based coolant in the system.

Does the sensor in the water pump require it to be grounded through the threads? I know some do, some don't. If so, perhaps it is a bit off, but the analog gauge is showing slightly higher temps as well, so I haven't really persued getting a new sensor just yet, but anything is possible. I did, however, reuse my old sensor when I installed the new water pump.

I wouldn't think that the screen is cutting back that much air, but I guess anything is possible.

 

Here is the screen in question. The wire looks slightly bigger than it really is, I guess because of the flash. Think it's cutting out too much air?

 

The engine making more power is not the source of your overheating.

The sensor threads do not act as a ground, in fact, they come with
anti-seize applied.

How much trouble to remove the screen for a test? If you are sure that it is not affecting air flow, leave it alone.

The digital sensor (water pump) is the more accurate of the two. The analog sensor/sendor is just an eye catcher.

You didn't answer my tstat question..... is it LT1 specific? Very important.

Are the fans operating as required? Very important.

The following link has some good stuff that may trigger a solution:
http://www.theherd.com/articles/lt1_cool.html

Now that I see your screen photo, that looks like a 50% reduction of air flow....... guessing.

 

Here is the new radiator. I bought it because I kinda thought it could damn near reverse global warming. The core is about 3/8" thicker than factory, the rows are closer together, and the fins have more contact points. I would think this alone would be enough to drop the engine temps on a basically stock engine, even with the screen I installed.

 

Without air flow, a radiator is just a reservoir. TOSS THE SCREEN!

 

Sorry, I misunderstood. Yes, the tstat is indeed LT1 specific.

The fans work correctly. Not only with the A/C, but temp as well. Both of them. It was my original thought that if the screen did cut back on air flow at speed, surely the fans would be able to pull enough to cool it off in traffic. This doesn't really seem to be the case. It does run a little cooler at lower speed, but not much. About 3 to 5 degrees or so. You are probably right. I should probably just pull it out and see what it does, but like an idiot, I installed it with the box out of the car. No real way to get to the screws without removing it from the car, but now I'm thinking that a 50% drop in air flow could very well be my problem. I was really hoping not, but you may very well be right... I was kinda having the train of thought that the better radiator could handle a little less air, but not too sure now... 50% is more than a little less...

 

Reluctantly,

 

Not only have you reduced the space for air flow, you have disrupted the path for clean air flow. Air trying to get through that screen is flowing in all directions, and very little of it is entering your pretty radiator/reservoir.

 

That mesh looks like its blocking about half
the airflow. Remove it and see how it runs. I bet it's the prob. You'll have to clean out the road debris every season but that's a small price to pay.

I too have an LT1, new aluminum radiator, electric water pump, 160 deg t-stat with good old green coolant. Reflashed PCM for ~185ish fan turn on. With ghis setup I don't think I've ever seen temps even reach 200, on a hot day with ac on it will cruise in the 170-180s and spirited driving will get to 190s.

 

Thanks for the second opinion. I was obviously over-thinking it. Screen will just have to come out. If I have 30% more radiator, and 50% less air flow, I'm obviously not helping anything. Yeah, I'm an idiot sometimes

When I get back in town, I'll pull the screen and post the temps so you all can laugh at me. Might as well, I'll be laughing at myself

 

I doubt any one will be laughing if the screen removal solves the heating problem. Most likely, you will hear a loud cheer.

 

My 93 can run very very cool (its a 383) but that is entirely dependent on what temperature I turn on the fans at.

There are two fans and they each have a low mph turn on level and a high mph (frankly don't know what the mph differences are) turn on level. I can make the car run in the 170's or the 180's or the 190's or the 200's or more simply by changing the fan on temp.

If you don't have chip making equipment than you can buy one mail order or you can wire the fans to turn on with a switch in the car if you are industrious enough. For my money I would get the chip changed.

FYI, my car will run in the high 170's if I use 85 C as my low mph turn on and 89 C as my high rpm turn on for Fan 1 and 89/92 for Fan 2.

The car will run about 205 or so if I use Fan 1 at 88/95C and Fan 2 at 92/98C. I do live in a cooler area now so that is with about 70 deg F ambient.

The former is more comforting but I think the latter is more efficient.

Perry

 

I honestly don't think the screen is causing much air-flow loss, but taking it out just to test it seems like a good idea.

Is the motor actually getting that hot? The sensor/sender may just be going bad. Go to auto zone or something and get a temp gun. Drive it to where it says it's overheating and shoot the block, temp sensor and radiator while running. This should give you the actual temp. These sensors are a bit of a pain and the gauge cluster on the C4s is notorious for giving inaccurate information.

I am now going to do a bit of a plug, so I'm going to apologize in advance. I highly suggest getting a bottle of Water Wetter from Redline. You completely flush (I know you just did that), make sure every single drop of the coolant is out, mix the pink stuff with pure distilled water and that is it. No coolant, just water and Water Wetter. It works miracles. It dropped the temp on my 91 L98 by almost 15 degrees.

 

The fans seem to cool it fairly well, but not like I thought it should. I do, however, have Water Wetter in it now. I've heard of some guys running more than one bottle at a time. I would run it with straight water and Water Wetter, but it's just like my luck that I'd have to leave it sit outside on a COLD winter night and something would freeze.

At this point, I'm just kicking myself for not just pulling the screen in the first place. If it solves the problem, great, but if not, I'm about at wits end with this thing. Reprogramming the fans is great at low speed, but it's 6th gear cruising that I routinely have a problem. I think my next move will be a 160* tstat.

 

A 160 stat has nothing to do with lowering your op temp. It just opens sooner than a higher rated stat. 160s are used in conjunction with fans operating at a lower temp, and will take longer to reach closed loop temps.

Once a 160 is open, it is just a hole in the system, and not a larger hole.

 

There are many guys who have installed screens sucessfully over the years.. but a removal test might be in good order.

I hate to say this, but in a recent post say maybe two months ago somebody here on the Forum's had discoverd a new All Aluminum radiator that had partially blocked core tubes do to a manufacturer flaw.. I hope this is not your case

I replaced mine two weeks ago W/1.5" Dewitts, and I Cruise at 188° OAT 105° So even though you are with in limits it does seem to run a tad hot.

Do you have a Coolant "T" at the 3/8-10mm Radiator Nipple, I do.. and during my work I found a restricted (Restrictor orfice) at the surge tank side of the T.