gta_knight

Hey guys,

I took the car for its first proper run out since completing the engine swap, ran really good but the temperature gauge was not my friend !

Ive got an aftermarket digital gauge in the car, and when the 5.0 was in there it would sit at about 78 degrees C, which is 172 degrees F, then if i was stuck in traffic the temp would obviously start creeping up so i would switch my fans on and i could see the temp start coming back down quite quick. Not a single problem.

Now tonight, it was hovering around 90-95 degrees C on the gauge, on the move ! then i got stuck in traffic and switched the fans on, and what the hell, it wouldnt bring the temp down much at all, maybe 5 degrees or something, it got upto 116 degrees C, 240 degrees F and i pulled over thinking it would be boiling over, the coolant level was above the HOT line on the bottle but it wasnt bubbling or anything, but i know from experience that at bang on 220 on the gauge on the 5.0 engine, it would start the bubble over.

So, a couple of things worth mentioning. the new water pump i fitted, i got off a friend as he didnt need it, he bought it for his 83 Trans Am. Tonight i was told that earlier cars had a water pump that spins the opposite way to what mine does, an 87m and ive probably got the wrong water pump on my car ?!?!

Its got a new radiator, new thermostat, new hoses etc etc, when i got the car back in the garage i checked under the hood and to be honest, everything seemed fine, the coolant was at the right level on the bottle, it wasnt bubbling, i felt all the hoses, all very hot, and i felt the rad too and that was hot.

Im pretty sure the temp sender and gauge are fine, i had no problems with the 5.0 engine.

aliceempire

iTrader: (14)

The water pump for and 83 is the same as an 87 as long as you still have the original v-belt type system. I took a look at your other threads and you still have the older style belts. I'd verify the temperature with a hand held temp gauge instead of thinking the digital is correct without proof. You could have a air bubble in the system yet, even though thats not a very common problem on a SBC. New thermostat or not it still could be problematic too. Also if you took the front end apart make sure you put the air dam back in.

gta_knight

Yeah its non serpentine. So that's kind of good in a way then if its the correct flowing water pump at least i don't have to change it

still got the same small air damn on the car. The rad cover, the black plastic thing was all warped and cracked so i replaced that with a nice grille, kind of like nicer chicken wire, so its full of holes to let tons of air through.

i always test a thermostat in hot water before putting it in the car and this new one opened up fine

hmmmm gauge check time first i think

gta_knight

I should have posted this thread in the cooling section, my apologies.

Ive just compared water pumps on rock auto side by side for an 83 5.0 and my 87 5.7 and they are listing all the same pumps so looks like your right there, that it will be the right type of pump.

Ive just ordered a laser temp gun to check it. but i never touched the air damn, all i done was replace the broken rad cover, that black piece of plastic that sits at an angle, for a flush grille like chicken wire

Joe Tag

iTrader: (4)

There are pieces that go on the bumper side of the core support to funnel air into the radiator. May be something to look into if you continue to have problems.

gta_knight

Its always been the shorter version without the side pieces and ive never had a problem but its something to look at.

is there a difference in radiators between a 5.0 and 5.7 because i bought this rad for my 5.0 then ended up pulling the engine, its an OEM style replacement one.

another thing worth mentioning is i deleted my oil cooler that sits above the oil filter, i had so many leaks from my old one, and i was told they aren't essential for the the engine i just left it out of the cooling system

NufNuffZ28

iTrader: (10)

Ifverything in the cooling system checks out. Make sure you're car is not very lean or the timing is off. Both can affect cooling as well...

racerx520

iTrader: (1)

if you have the radiator cap off, you should be able to see the coolant flowing through the top of the rad, if you see that, then i'd say your water pump is working fine. i havent looked at all the replies, but are your fans kicking on at the appropriate temp? or at all? is it a new thermostat? also did you replace the coolant temp sensor in the head? when i swapped the 350 tpi into my t/a, i noticed the temp higher than normal, turned out the sensor is bad. i used a laser thermometer on the intake manifold and showed it was running at 180 degrees, although the gauge said it was over 220.

gta_knight

Ive actually got my fans on a switch, they kicked in too late on the 5.0 so i didn't want to chance it.

i fitted a new temp sender on the front of the intake, but reused the sender for the gauge in the car that goes in the side of the block from the 5.0, everything was working great in the 5.0, i cant imagine i would of damaged it taking it from one engine to another

ive ordered one of those laser temp guns today so i can check the actual temp

racerx520

iTrader: (1)

i also had an issue where i noticed my temp creeping up while driving one day, i had been driving it for about 3 weeks on the weekends at that point. found the problem on that one was the rad cap was leaking and it wasnt causing a vacuum to suck the coolant from the overflow tank, so the radiator was going dry, dont think this is your problem though.

can you see in the rad if it is pumping fluid? maybe one of the coolant passages is somehow blocked in the heads / intake manifold?

gta_knight

Yeah the coolant goes up n down depending on the temp so that's ok.

ive got a transmission fluid leak from one of the lines that goes to the rad so i need to fix that first before checking the water flow, in not sure if this is contributing to the problem, the rad must have a separate part just for the tranny fluid if it goes in the radiator?

racerx520

iTrader: (1)

it has a transmission cooler inside the radiator, yes.

gta_knight

I fixed my transmission fluid leak tonight, ran the car up, the temp climbed slowly and steadily just sitting in the garage.

so i thought id take it for a drive, i was out for about 20 minutes and all was fine. The gauge was still reading hotter than what im used too, it was going between 85-90 degrees C (around 190 degrees F) and this was constantly on the move.

I put the car back in the garage and just let it run and it started getting hotter obviously, i switched the fans on when it got to 100 degrees C on the gauge (212 degrees F) and it came back down to about 200 according to the gauge, but wouldnt go any cooler.

I opened the hood after switching off and again everything seemed fine, the coolant was on the HOT mark on the bottle, the engine didnt feel overly hot, all hoses were hot, the top rad hose felt a bit squidgey, so the thermostat must be open if waters going all the way around the system.

I turned my heater on too and i get nice hot air through that.


Sooooo, back to my original question i guess, does this seem normal for a 5.7 ? im just used to the car running 20 degrees cooler when i had the 5.0

aliceempire

iTrader: (14)

Are you running a single electronic fan? If so, going down to 200 would be about what I expect. My car does about the same unless my second fan is on too. I think there was a heavy duty radiator available for higher output motors but don't qoute me on it. I'm running the original TBI radiator and don't have any problem with my mildly upgraded 350 tpi.

gta_knight

Ive got twin fans, and they both run at the same time.

its a brand new rad, same as my old one, stock replacement type

RBob

iTrader: (1)

If running the stock 195* F thermostat, running at 200* F by the gauge is normal. The gauges aren't always that accurate either. I usually go by the CTS via the ECM's data stream.

I'm not sure why you placed the screen in front of the radiator, there isn't anything there from the factory. That type of screen is going to block a lot of air flow.

RBob.

gta_knight

There was a black plastic shroud thing there originally, but it was all cracked and warped, the grille shouldnt affect any airflow as its full of holes, i just put it on incase any large stones kicked up while on the road and hopefully it would stop them from making a hole in the rad.

Its got a 160° stat in there.

My temp gun turned up today so i thought id give it a try. I got a few different readings depending on where i pointed the gun. But basically the car ran for just over 20 minutes, idiling in the garage, i turned the fans on and off according to the temp so it didnt get too hot and it did cool down. The reading from the gun changed depending on where i pointed it, but on the intake and top hose is where it was around the same. Pointing it at the sender for the gauge didnt work as i think the heat from the headers was bumping the temperature up quite a bit









These were taken with the car running after the fans had been on. A few of my UK friends with 5.7's have said theirs runs a bit on the warm side too.

So maybe this is just what the car is going to be like then, its definatley not overheating