0Tom@Dewitt

I wish someone gave me a dollar each time I heard about the trapped air problem and the burbing requirement necessary to get cars from overheating. I've had this discussion with many professional car restorers and when asked how many times they ran into this problem the answer is always, never. Air will always seek out the highest point in the system, which is usually the cap, and the air will get pushed out when the system expands. Worst case scenerio, you remove the cap until the thermostat opens and BURP, goes any air. Think about it, how many cars does the dealer have to burp before they delver them to the customer?

MVP'S ZO6

^^^^this

danieloneil01

Washed everything out with the water hose and got good flow out of the engine and radiator (did them separately). Rinsed the engine and radiator with purified water that I got from HEB. Used pressure washer on condenser from both sides but started on the back side first to push out the dirt the way it came in. Threw in new 187 tstat and filled it up and burped it. Drove it and was excited that it went to around 205 then went backed down to stay around 194* while cruising. At a stop light it goes up but quickly goes back down once moving. So I turned on the AC and it slowly but surely went up to 230* before turning it off. My AC during the whole time wasn't as cold as it should be and before trying to fix my overheating issues with the AC on my car would shut the AC off quite a few times during a drive and more so during stop and go and not so much at speed. I got home and turned the AC back on and watched it slowly climb while not blowing cold AC. I only have a cheap gauge and checked the low side and it was 45 psi and the line was cold.

Got home and turned the AC back on while idling and it went to 230* so I checked the fans and both were at full speed and pulling the air through the radiator to the engine. But I know there's a gap all around between the condenser and radiator but it seems not a whole lot of suction at the front of the condenser for how fast both fans are running.


How am I supposed to seal this area if you have to? My condenser seems like it's clean enough too.

ajrothm

Atleast you have it running cooler at hwy speeds now, so you did some good.. However the 230* with the AC idling, well, that's just how it is.. Welcome to the club. I've spent 2 years trying to solve the issue.. The problem is the intercooler in front of the radiator and very little gap between the IC and the condenser at the bottom to suck air up through..

Mine will run 205-212* on a 92* day at 70 mph with the AC blasting.... As soon as I come to a stop and idle, the temp starts climbing.. I can easily see 230* within 10 mins of idling after a freeway ride. -- back on the freeway I'll cool back down slowly depending on the amount of cars in front of me...(blocking my air flow).. And get back down to 212* or less.

All of my testing is with the AC on.. Who the FK is gonna drive with no AC..lol

ajrothm

No way would I have put a 187* stat in there... Even IF the cooling system could get it colder, that stat is gonna be keeping it in the 190s and forcing it to get there quick..

danieloneil01

Anybody use foam insulation to seal up the radiator to the condenser? As it is now I cant run the AC at all, even on the highway without it getting to 230 and beyond. Should I move the homemade air dam to the condenser?

ajrothm

If its getting 230* on the highway at 70 mph with no cars in front of you, there is something wrong....more so then radiator seal.

Are you losing any coolant? oil clean? excessive bubbles in the reservoir?

You may ought to do a carbon litmus paper test of the reservoir to check it for hydrocarbons...(indicating a leaking head gasket)...

What does your timing tables look like at cruise rpms/TP%?

I could see 215...maybe 220* at the HIGHEST for highway cruise on a 95* day with the big ECS intercooler in front of the radiator but....

Defintely make sure your air damn is full and in good shape. You have the cover over the IC/air filter right?

Yours is running hotter then mine in the same weather and mine is iron block, spinning a way harder blower to turn...There is definitely something out of the norm going on.

danieloneil01

I don't have a head gasket leak or anything. Oil is clean and everytime I've drained the coolant it's looked clear as water. Car runs fine now on the highway and idling WITHOUT the AC on. It only gets hot idling and cruising with the AC on.

Yes I have the ghetto ECS cover but I've had to cut it because the hood hinges would get in the way when closing.

After running the car the first time I loosened passenger side rear steam port and it took forever for the coolant to come out and I did this to all four. But no difference in running the AC.

Like I said something has to be up with the little air flow I have coming through the condenser with both fans on full tilt.

danieloneil01

I sealed the condenser to the radiator all the way around and still no good. You can tell in the log when I turn on the AC because the temp slowly climbs up. I jacked the car up and both fans were running and I forced high speed and they didn't go faster. AC was cold though but at this point I'll live with no AC for the time being. The condenser looks pretty damn clean too. **** it


Have anything to do with the issue? Does this for about 30-45 seconds on cold start up? Noise sound like it's coming from the driver side.

danieloneil01

Going to cancel dyno tune and once I feel like figuring out the issue I'll start removing the driver side :head. Oh I really hate this disease. Maybe I can find a good stock cube long block for cheap before I leave or just wait until I get settled in Tulsa when ever that will be.


Starting to wonder if this is why my car is having cooling issues. Guess I'll pull the plugs and do a compression check and possibly a leak down test while I'm at it.

Y2KRoadster

Dude, why are you going to remove the head? If the problem is ONLY happening when turning the A/C on, then removing the head isn't going to solve anything.

danieloneil01

The ticking noise is why I'm debating on removing the head.

danieloneil01

Compression is fine, all between 150-160psi. Removed spark plugs, fuel pump fuse and coil harness and bumped the starter 3-5 times until the gauge stopped increasing.


I've been told it could be a lifter pumping up. Is this normal and something to not be concerned with?

ajrothm

Damn... That doesn't sound good. Definitely something to be concerned with... Doesn't sound like a lifter too me but...

Did it just start doing that? Does it do it cold and hot?

Sounds like a rod knock to me, or some bad piston slap.. But I have had sounds like that before on other engines that turned out to be just stupid stuff that sounded bad...

Youre definitely gonna have to investigate, don't run it hard til you figure it out what it is...

momo20

i just got my ecs kit installed the paxton novi 1500 and so far while driving i am at 175 to 180 on the hwy where as i used to be 185 to 190 that is with a 160 degree stat even while setting at a light i maybe got to 185 to 190 where as i used to be 195 to 205

danieloneil01

Drove it to work. Temp without AC on at 70 mph was between 203-208*. Going below this the temp will stay around 198-203*. Pulled into the parking space and let it idle for a minute and it stayed around 212* and this is with a 187* stat in 80* weather. Oil pressure at 70mph is around 45 psi, when I got to work and in park it was 26 psi. All this sound normal?

As for the sound I drained some oil and threw in some mystery oil. Someone said it could be a stuck check valve in the lifter. If it is then it should make the sound even if the engine is warmed up and starting it a few minutes after shutting it down.

Also, when I pull the spark plug on #3 the noise goes away and comes back when I put it back on. During the short time it makes the noise I had it in park and gave it some throttle and it goes with the rpms. I'm still going to get it dyno tuned Tuesday because I like living on the edge brah

danieloneil01

Okay I take it back, I'm not going to get tuned. I went out and the noise started upon start up with the oil and water being 170* and when it went away I gave it some blips of the throttle and it's still there when the rpms raise. Sounds like a really bad lifter.

Odds my cooling issues are because of a hurt engine? Could a motor not firing correctly on 1 cylinder cause the engine to run hotter since it's trying harder to get the vehicle going? Then throw in trying to run the AC that causes more load on the engine? Exhaust valve not opening all the way due to a bad lifter?????

danieloneil01

Yes and yes now that I went out and verified it just now. Is removing/installing an engine in the C5 easier than the auto swap? lol

ajrothm

If you pull a plug wire on #3 and the noise quiets or goes away, then its likely a rod bearing.. It could also be a wrist pin but not likely. Removing the load (the combustion) off the piston/rod that is injured usually lessens the noise.. Then you know which one is hurt..

I don't think you got the engine coolant temp hot enough to hurt it... 240-250* could hurt a gasket, that's usually about it.. However if you got any kind of coolant in the oil, it will take the bearings out quick.

Sucks man... But you better just pull it and tear it down before it's really hurt...(like eating the crank or hurting the block with a broke rod)

Time for forged pistons/rods/studs.. 800hp

danieloneil01

I changed the oil a couple days ago and it was clean as was the coolant both times I've dumped it in a weeks time. It sucks because cruising it seems like it's okay. Guess if I keep driving it it'll only get worse if it is a bad rod. I'll have plenty of time to determine where to go from here since I can't do anything while my house is for sale.