Sr20det cooling issue...need help!

[thegentlemen]

Bought the car about a month ago with the sr swap already in it. Had to fix a few things on the car due to neglect from previous owner. But once I got the car to the point where I could take it for a drive, as I was driving it around I noticed that it ran a little hot but never over heated. I decided to change the thermostat and flush the system, that seemed to help but only for about a week. The car then started to heat up again as I got on the highway and got up to higher speeds of about 70mph. Pulled over, let it cool and it seemed to be fine after that without heating up. Throughout that night it started to run hot again, so I took it home and replaced the waterpump after not seeing coolant circulating through the radiator. Started the car up to bleed the coolant system of air and I noticed it was just idling hotter than before and it took forever to get the new oem thermostat open. Once it finally did the motor didn't seem to cool down at all. I shut the car off and began to inspect the coolant hoses water pump etc, and saw that the radiator was leaking from the fins and dripping onto the floor.

My question is: could this be a clogged rad? Previous owner had dex-cool in it when I purchased it, so I drained it all out and did a quick flush

[conrad_s13.5]

more than likely man,. seems like you damn near have done everything else id say to check.

You still have a clutch fan and shroud, or electric fans?

[Greenwood23]

Dumb question: did you make sure that the Nipple on the thermostat was pointing up? I have made this mistake in the past.

[thegentlemen]

more than likely man,. seems like you damn near have done everything else id say to check.

You still have a clutch fan and shroud, or electric fans?
No the guy I bought it from has two 12" fans wired up to a toggle switch, when driving the car I had to have these fans on and running constantly even when I was on the highway
Dumb question: did you make sure that the Nipple on the thermostat was pointing up? I have made this mistake in the past.
yea I'm pretty sure it was pointing upward. I may just double check so I know for sure

[jedi03]

switch back to clutch fan or get better fans an controller that turns fans on automatically

[jedi03]

+1 on checking thermostat...backwards can cause overheat ez

[thegentlemen]

Update: replaced the thermostat with a new one (bleeder on the thermostat upwards at 12 o'clock position) bolted it all back up, jacked the front end of the car up in the air, pulled the bleeder out of the upper water neck and slowly added coolant until a steady stream came out of the bleeder hole then put the bleeder back in. Continued to slowly add more coolant until it was filled to the tippy top of the rad, started the car up and everything was fine. I then let it idle for about 8 minutes and the needle climbed to about 3/4 on the gauge so I shut it down to check over the system. Nothing looks abnormal, the only thing I can think of that's a issue would be the headgasket at this point.

When I pull the thermostat out and run without it, it's doesn't overheat and runs fine and does not overheat.

[jedi03]

were ur fans running while u idled it?

[cotbu]

Try starting the car with the cap off, does coolant shoot out?
add too you bleeding procedure the heater, turn it on full blast.

[HPKMotorsports3]

check the fans and make sure they are pulling the air out of the rad and not pushing it into the cool air as your driving...

[thegentlemen]

were ur fans running while u idled it?
Yessir, as soon as it reaches to where it should normally be on the gauge I flip them on
Try starting the car with the cap off, does coolant shoot out?
add too you bleeding procedure the heater, turn it on full blast.

No coolant shoots out when I let it idle with the cap off, and when it hit the normal temp on the gauge I've tried once or twice turning the heat on full blast and it doesn't do anything. Still heats up

I've also considered the temp sensor on the gauge pod possibly being bad. I'm getting a stock fan clutch and shroud off a friend hopefully tomorrow or sometime this week to try and eliminate that possibility. I'm thinking because of the way the fan clutch works that if it's not turning on while the car is idling and the temp gauge is reading hotter than normal and it's not turning on, sensor must be bad.

All in hopes to get this bug worked out or figure out what I'm doing wrong, if anything. Thanks for the insight guys, keep it coming

[thegentlemen]

check the fans and make sure they are pulling the air out of the rad and not pushing it into the cool air as your driving...

Yup it's pulling the air out of the rad and not pushing it, I checked that when I pulled the rad out and flushed it

[chituntang]

What gauge you get you temp readings off of? If you are still on the stock cluster, can you confirm that the temp sensor on the engine is for usdm chassis? This is a common mistake...

[thegentlemen]

What gauge you get you temp readings off of? If you are still on the stock cluster, can you confirm that the temp sensor on the engine is for usdm chassis? This is a common mistake...

I'm not so sure that the temp sensor is usdm or japan one. How exactly do I go about checking this?

[xSoCalxRiderx125]

Warm up your car and touch your radiator in different spots. If one spot seems colder than others you most likely have a clog. Another thing you could do is take your oil dip stick out clean it with a rag and try to slowly push it downward into your rad if it doesn't go down to the bottom then again it maybe clogged. The dipstick is limited to where you can check it buts its a cheaper alternative than to start blindly throwing money into different shit. My advise is to just get a new rad. I myself just got done dealing with overheating sr bullshit and turned out to be my radiator filled with rtv or some type of bs. Hope that helps brotha.

[thegentlemen]

Warm up your car and touch your radiator in different spots. If one spot seems colder than others you most likely have a clog. Another thing you could do is take your oil dip stick out clean it with a rag and try to slowly push it downward into your rad if it doesn't go down to the bottom then again it maybe clogged. The dipstick is limited to where you can check it buts its a cheaper alternative than to start blindly throwing money into different shit. My advise is to just get a new rad. I myself just got done dealing with overheating sr bullshit and turned out to be my radiator filled with rtv or some type of bs. Hope that helps brotha.

The radiator thats in it is a practically new Isis. Although That's the one thing I have not actually done just yet. I have noticed that when I have the thermostat in and I'm trying to let the car idle and wait for the thermostat to open, the left side of the rad (lower rad hose) is still cool and not hot/warm like the right side is (upper rad hose). I've never heard of the trick with the dipstick but I will give it a shot.
However, without the thermostat in the entire radiator, when I touch it, is warm/hot all over not just in one spot.

I did pull ther rad out and put a garden hose to it to flush it out and water seemed to flow very well and didn't see any debris come out of it. There was a thermostat installed by the previous owner that had a sufficient amount of rtv on the thermostat housing when I pulled it off to replace it.

Thanks for the input man, I'm gonna try and source another rad tomorrow or sometime this week to try your advise

[chituntang]

I'm not so sure that the temp sensor is usdm or japan one. How exactly do I go about checking this?

I do not have an answer to that... You just need to use something else to test your temp reading. If the thermostat opens (lower radiator hose will be hot) for a min or 2 and the gauge reads higher than normal, the readings are off. Or you can get one of those infrared thermometer gun, just point and shot.

[nissansrdub]

what radiator cap is on it? aftermarket ones may have different operations temps. ??? i dont know just throwing it out there, cant hurt. joe good luck

[thegentlemen]

I do not have an answer to that... You just need to use something else to test your temp reading. If the thermostat opens (lower radiator hose will be hot) for a min or 2 and the gauge reads higher than normal, the readings are off. Or you can get one of those infrared thermometer gun, just point and shot.
I have never heard of that thermometer gun you mentioned but that would be pretty cool to use and test it. As for now I am going to get some sort of water temp gauge and give that a shot. Seems as that would also let me know if it's a faulty temp reading along with using the stock fan and shroud.
what radiator cap is on it? aftermarket ones may have different operations temps. ??? i dont know just throwing it out there, cant hurt. joe good luck

The cap that's on it is the one that came with the rad, it's a Isis 1.1 bar cap. When I try another rad Im going to use a different cap also

[huffandpuff00]

air bubbles, drill another hole on top of the stat to help the air bubbles through

[huffandpuff00]

also only buy the oem nissan stat, i had 2 other brands not open

[thegentlemen]

also only buy the oem nissan stat, i had 2 other brands not open

Oem Nissan thermostat is what I used and that didn't help

[daftphunk]

What kind of car? What kind of engine?

I have an S13 SR in my S14. The temp gauge sensors are different for both cars. I didn't switch mine out and thought I was overheating all of the time. I bled the shit 90000 times and would always get pissed, thought I blew a HG or something, etc.

Anyways, swapped the sensor, or rather the sending unit and everything was fine.

[greenwood]

I would put the thermostat in boiling water and see if it pops open.

Looks like you are close to nailing the issue.

what kind of temp guage are you running? I like ones that give an actual read out. I do not trust the stock temp guage.

[blueshark123]

seems like u need to bleed it better, samething happend to me. I just had to keep bleeding

[thegentlemen]

What kind of car? What kind of engine?

I have an S13 SR in my S14. The temp gauge sensors are different for both cars. I didn't switch mine out and thought I was overheating all of the time. I bled the shit 90000 times and would always get pissed, thought I blew a HG or something, etc.

Anyways, swapped the sensor, or rather the sending unit and everything was fine.

I'm not so sure on the year of the motor but it is however a blacktop sr. That's exactly what I have done so far, I couldn't count how many times I've tried bleeding the system and still get nothing, it just slowly climbs to hot in the same amount of time. I have never changed any of the sensors so I was considering the temp gauge one being the issue

[thegentlemen]

I would put the thermostat in boiling water and see if it pops open.

Looks like you are close to nailing the issue.

what kind of temp guage are you running? I like ones that give an actual read out. I do not trust the stock temp guage.
I'm just using the stock temp gauge. I have put the thermostat in boiling water and it opens open before it starts boiling. I have tried this with 3 diff thermostats that I have tried in the motor. Hopefully I nail this issue soon!
seems like u need to bleed it better, samething happend to me. I just had to keep bleeding

That's what I tried yesterday, tried bleeding it 5 times In a row for a total of about an hour and didn't get anywhere

[xSoCalxRiderx125]

Buying a brand new thermo from Nissan couldn't hurt. Two of my thermos that I bought opened when I boiled them but were stuck shut when installed on the car. Couldn't hurt spending 25 bucks on a new thermo.

[thegentlemen]

Buying a brand new thermo from Nissan couldn't hurt. Two of my thermos that I bought opened when I boiled them but were stuck shut when installed on the car. Couldn't hurt spending 25 bucks on a new thermo.

Yeahi thought about getting another Nissan one but cheaped out and bought a autozone one for just 10$.

UPDATE: had my cooling system checked for a blown had gasket at a local shop today and it ended up being just fine! So now it's on to figuring out the issue being something else

[blueshark123]

jack ur car by the front have it high in the air and try bleeding, also get a 2l coke bottle cut of the bottom of it and wrap the cap end with electric tape till u can make a air tight seal to the filler neck in the radiator like a funnel.then fill up the bottle and wait to see all the air come out

[thegentlemen]

^ that sounds like a pretty damn good idea man! I will be giving that a shot once I get the oem fan and shroud on there and eliminate the junk eBay ones that are on there.

[Chay G]

i think you have a s14 temp sensor, get one for a s13, it costs like 13 bucks in autozone

[daftphunk]

I'm betting you have the wrong sending unit. There's two sensors or whatever at the intake manifold. One is the sensor which should be fine, you need to replace the sending unit with a correct one for your tach I believe.

Prob got an s13 one which will send double than what it actually is with an s14 or vice versa.

[thegentlemen]

I'm betting you have the wrong sending unit. There's two sensors or whatever at the intake manifold. One is the sensor which should be fine, you need to replace the sending unit with a correct one for your tach I believe.

Prob got an s13 one which will send double than what it actually is with an s14 or vice versa.

So what your saying is I should try an s14 sending unit? Because the s13 one sends double the reading?

[thegentlemen]

I also went to the junkyard yesterday and picked up a nice ka fan clutch and shroud that I'm going to stick on there. Hopefully get those put on tomorrow to see how that works out for me, and to also eliminate these junk eBay fans (or whatever they are) that are wired to a toggle switch.

[chituntang]

I do not think you can run KA fan and shroud on an sr...

Run a USDM S13 Temp sensor, you may have a JDM one on the engine...

[project_silvia]

yea what is being said about the temp sensor is true i have an s13 sr in my s14 and i though i was over heating and it was that..

[project_silvia]

also have tested the radiator to see if its holding pressure?. same for the cap ?

[thegentlemen]

Anyone know if there is a plug on the oem harness that I could wire the electric fans to so they turn on themselves when needed? I was searching around and found a thread about a guy using the 93-97 altima electric fans and he just plugged them into a existing plug on his harness.

To my knowledge there isn't a plug that you can do this with, hence why they use mechanical fans stock. But then again I could be wrong that's why I'm asking?

[Jaescrub]

^i got a fal fan setup and it came with a temp control box that turns them on based on radiator temps I love that it works like a oem electric fan.

[chituntang]

Anyone know if there is a plug on the oem harness that I could wire the electric fans to so they turn on themselves when needed? I was searching around and found a thread about a guy using the 93-97 altima electric fans and he just plugged them into a existing plug on his harness.

To my knowledge there isn't a plug that you can do this with, hence why they use mechanical fans stock. But then again I could be wrong that's why I'm asking?

The S chassis still has efans on them, for ac and overheating purposes...
You will find a plug that plugs the fan into the car but there are 2 plugs on the Altima efan setup...

[thegentlemen]

The S chassis still has efans on them, for ac and overheating purposes...
You will find a plug that plugs the fan into the car but there are 2 plugs on the Altima efan setup...

Nice, I'll have to look more into that. Not quite sure how that would work, But from the sounds of it I'll have to use the a/c button for them to kick on.

I'm just in debate on going oem mechanical setup with sr shroud, or upgrading the cheap Efans that are on it now. I mostly just want to eliminate the toggle switch altogether

[MudRacer]

Dude I have the same exact issue as yours.

I have an S13 blacktop SR20det in my S14 and No matter how many times I bleed it, it still overheats.

I am thinking about replacing the temperature sensor to an S14 one and see if that matters. Also installing an additional temp sensor in the upper hose with an aftermarket gauge. Ill let you know what happens.

[thegentlemen]

Dude I have the same exact issue as yours.

I have an S13 blacktop SR20det in my S14 and No matter how many times I bleed it, it still overheats.

I am thinking about replacing the temperature sensor to an S14 one and see if that matters. Also installing an additional temp sensor in the upper hose with an aftermarket gauge. Ill let you know what happens.

Cool deal man, lmk! I'm in to see who figures it out first!

I just replaced my temp sending sensor today with one I got from a spare ka24e motor today. So I'll see how that goes

[thegentlemen]

UPDATE: s13 temp sending unit sensor (ka24e) did not help, it actually read higher than the one that was in it did. So I swapped it back and I'm going to stick with that. Next i will be trying a few things with the thermostat itself to see if I can get more air out of the system than what I have been able to do before.

[chituntang]

Is the bottom radiator hose hot when the gauge is reading high?

And stop toying with the thermostat. It either opens or not. Once the car is up to temp, it should open (do not read your cluster temp as you do not know if its working). If the top hose to the radiator is so hot that you cannot touch it at the same time the bottom hose is still cold (bottom hose gets hot when coolant flows to the engine, which means thermostat opens), then you have a bad thermostat. If not, then your cluster/sending unit combo is wrong and not reading the right temperature. Go get a aftermarket temp gauge if you still have doubt. For my SR'ed car to warm up in GA weather sitting at idle, it would take almost 10minutes. You live in a colder climate so it should take longer.

[dr.klawn]

air bubbles, drill another hole on top of the stat to help the air bubbles through
that works really well! high heat down south was getting me until i drilled a couple of holes to allow the coolant to flow before the t-stat fully opened

[93sr20]

my b13 use to do the same thing and all I did was change the radiator cap and problem was solved

[Luvs2slide]

Get an reputable aftermarket water temp guage installed and verify your temperatures. I never trust the stock guage EVER.

Seems like your doing everything else right so far.

[Trap Star]

I had a problem like this with my SR. Bleeding didn't help, koyo didn't do anything, new water pump didn't help, neither did a nice set of Flex-a-lites. My headgasket ended up going out on me. Removed my head and found this horrible crystalline shit in all of my coolant passages, some were completely blocked. :(

http://i171.photobucket.com/albums/u292/baconbitz99x/S13/P7150610.jpg
http://i171.photobucket.com/albums/u292/baconbitz99x/S13/P7150609.jpg

Hopefully this isn't your issue, but I figured I'd throw it out there as a possibility.