ka24de overheating about to drive it off a cliff!!!

[Unstock240]

Well I swapped in a ka24de in my 1989 hatch. It is having really random overheating problems and i'm about done with this pos. Things I have done: New thermostat,waterpump,radiator cap, silicon hoses, radiator isnt clogged, system cleaner, and system flush, and now I'm running no thermostat and it still persists, also a pressure test and it didnt leak down for about 10 minutes. No leaks since my coolant level hasnt changed in a weeks time.

It runs right at middle gauge forever. I just drove 60 miles with no problem, mostly highway. Then on the 60 miles back it was fine all the way till I pull in my drive. Just then it starts to heat up and I hear gurgling. It seems to get hot after a long drive, then a few idling or slow moments it goes up, high rpms will sometimes bring it down. I have 3 clutch fans and all have about the same resistance so I dont think thats the problem either.

Seriously what else could it be??? Not the temp gauges either, when in the middle i put a temp in the radiator and right at 170F. Any help would be great. This has been ongoing for about a month, and sometimes its fine for a week, then it overheats like wtf? I don't know but I'm not rebuilding this thing again, if anything ill find another ka24de to drop in.
Modified by Unstock240 at 8:18 PM 9/15/2009

[youngun21a]

So u have it with no therma..and it still overheats does it only overheat when it's park or when u drive too..i blame the clutch fan.I know u said u try three....do u smell any coolant..also when u have it on and the radiator cap off do u see a river of water flowing..

[Unstock240]

I let it run idle for like 35 minutes no problem. It flows good, but I need to look while its too hot. I need to make my clutch fan solid and try that.

[needfaster240]

I let it run idle for like 35 minutes no problem. It flows good, but I need to look while its too hot. I need to make my clutch fan solid and try that.

does it do it with the a/c on or any time? what are the chances your getting compression in the coolant system?. does it do it while in traffic...highway only i the city all of the above? im havin the same problem and i am having trouble diagnosing it. im hoping i can get a couple ideas from puting a couple heads together.

[the converted]

Check to see if buble are coming out of the radiator when it is running.

[Unstock240]

One thing I forgot to do is a compression test and see if the cylinders leak down. When I fill the coolant almost spilling over the filler neck i would see a few tiny bubbles now and then, but not sure if it was from the like turbulence or not. It never seems to overheat until at least 30 minutes. I would say all the times it happened when restarting or idling or driving probably 35 stop and go.

Just did a compression test and got 127-125-125-124. I need to go back and do it again, i forgot to hold the throttle open. The good was no leak in psi on any for about 1 minute each.

Ok I got 1-165 2-155 3-170 4-163 Not bad but not the best.

Modified by Unstock240 at 9:04 AM 9/16/2009
Modified by Unstock240 at 10:03 AM 9/16/2009

[blacksrjdm]

Is it definately overheating or are you just going by the gauge. If you are just going by the gauge, make sure that it is in fact overheating and you dont need a temp. switch for the gauge.

[Unstock240]

When the gauge rises I could hear the coolant start to gurgle and the overflow was almost full every time. I changed my temp sensors since before it read too low, so no problem there. With the gauge in the middle the coolant in the rad was 170 so i think my gauges are right on. About the ecu sensor I can't be sure.

Another thing to note: the last time it got hot, all I did was shut it down for like 10 minutes then it was perfectly fine for that day. So when it all cools off its good to go for awhile.
Modified by Unstock240 at 9:21 AM 9/16/2009

[ghx407]

Running without the thermostat could be your problem because the coolant might be flowing too fast through the radiator; thus not giving it enough time to cool down before going back into the engine.

Have you bled the system? KA24DEs are notorious for having air bubbles in the cooling system...

[Unstock240]

When the gauge rises I could hear the coolant start to gurgle and the overflow was almost full every time. I changed my temp sensors since before it read too low, so no problem there. With the gauge in the middle the coolant in the rad was 170 so i think my gauges are right on. About the ecu sensor I can't be sure.

I thought about putting the thermostat back in, but it overheated with in in so i dont think it will matter. I boiled it and it opened at 170 or what the manual said.I also took the time to jack the front up every time rev it bleed it purge it whatever, no luck there. Maybe it really takes some special touch to bleed these things, maybe that explains why I can go a week or so?
Modified by Unstock240 at 1:37 PM 9/16/2009

[nuts510]

Install a Nissan thermostat, then bleed the system and let the car idle until it reaches operating temperature with the radiator cap off watch the water circulates good and does not tend blowout the radiator cap and if it does best and you could be dealing with the shock radiator. I am very suspicious of the radiator because you say you can drive it for about 25 minutes before it overheats with a thermostat you would make it much more than 5 minutes does it seem to be worse if you're underload load on the engine like going up and down Hills that also tends to point to the radiator if it's doing that

[the converted]

Do a leak down test and see where your loosing the compression to.

[locoluna825]

dude change your fawking fan clutch fan i run mine without a thermostat no problems here i have alot of problems with electric fans sometimes mine don't kick on my car overheats when its jut idling but if the fans working its fine. change that fan clutch or buy a electric back up fan you done everything else you possibly can.

[blacksrjdm]

I just drove 60 miles with no problem, mostly highway. Then on the 60 miles back it was fine all the way till I pull in my drive. Just then it starts to heat up and I hear gurgling. It seems to get hot after a long drive, then a few idling or slow moments it goes up, high rpms will sometimes bring it down. I have 3 clutch fans and all have about the same resistance so I dont think thats the problem either.

Modified by Unstock240 at 8:18 PM 9/15/2009

Obviously by this statement you very obviously need a new clutch fan. Not a doubt in the world. No need for any further discussion until you have replaced the fan, put in a Nissan themostat, and bleed the system. No need to post anything else OP. Put a new clutch fan in it, and it will stop overheating.

I mean think about it. You drove 60 miles and it didnt over heat until you stop, therefore, while driving there is air passing through the radiator and cooling your engine. When you stop. guess what, there isnt anymore air passing through the radiator to cool it. Thats where the clutch fan comes in. If you are missing the shroud, then make sure to replace the shroud when you replace the clutch fan.

Also, the clutch fan is not the fan itself, it is however the clutch hub that the fan bolts to.

FIX IT.

[locoluna825]

[Unstock240]

I went ahead and put another clutch fan on from a 95, I know it's not new but I might as well try. My current fan is yellow while this one is white. Maybe the clutch was acting up only when warmed up. I think ill take one fan and make it solid to see if it solves it, if so then ill buy a new fan. I might as well buy a new radiator since it has been taken apart and cleaned from the last owner.

[needfaster240]

i have to agree it sounds like the fanclutch. im gonna try electric fan. and eliminate the mechanical fan. gimme a few extra ponies. with 200k miles it needs all the help it can get.

[Unstock240]

I plan on eliminating the fan and run electric as well, I'm just trying to get this solved. The other clutch fan didn't help, but both had about the same resistance. I will make one clutch solid and try that out. Again ran fine today for about a 30 mile drive, I pull in the lot then it just started to rise, thankfully I was parked and shut it down.

[locoluna825]

i didn't see did you say you replaced the pump yet?

[the converted]

Do you have the fan cowl in there?

[blacksrjdm]

Is the fan shroud on there?

[Unstock240]

New water pump and yes I have the shroud on. My car doesnt have that plastic skid plate thing under it anymore would this be a big enough problem?

I read on an rx7 forum without that underside plastic piece isn't good. I'm thinking maybe all that air is cooling the clutch fan so it wont spin?
Modified by Unstock240 at 8:27 AM 9/17/2009

[locoluna825]

the underbelly plastic shouldnt be that big of a deal it reduces drag by keeping stagnant swirling air out form the engine bay more for that than for cooling purposes, don't get me wrong though, it helps, but i really doubt it will keep you from overheating.

like i said earlier i run ONE electric 14 inch fan no shroud just right up to the radiator, it gets to 110 degrees like nothing during the summer and it still keeps my car cool, does overheat if that day fans not working though.

[the converted]

If the plastic splash shield was going to do something, it would be at higher speeds rather than lower, so I highly doubt that is any issue. Have you checked to see if you are getting a constant flow of bubbles in the radiator that might indicate a bad head gasket? The only things I can think of other than that would be your a/f mixture or your timing being way off.

[needfaster240]

the fan hub/clutch is spins off the engine not the air flow. viscous fans are made of tempurature sensitive metal that engages the fan at a certain temp. so if you jb weld one where it stays on all the time.it should give you the answer your looking for. ...its not :the radiatorthe water pumpnot the thermostatnot the timing ( if it were it would run very bad) not in the a/c system one thing it can be......... the fan clutch