Did the supercharger require you remove the factory fan and convert to an electric fan? Electric fans don't work nearly as well at cooling the engine as the factory serpentine belt driven fan does.
Overheating after supercharger install
- Thread starter Crashmymax
- Start date
Yes that was the only modification to the cooling system. Mechanical fan is gone electric fan installed. I'm also trying to figure out if I have a factory radiator or a cheap aftermarket. Anyone know where I would find a mopar marking of some kind on the radiator?
Was that modification, replacing the OE fan with the electric fan, specifically required to install the supercharger?
Always go Mopar with the radiator, others don't cool as well or have sufficient excess cooling capacity unless you pay top dollar for it.
Always go Mopar with the radiator, others don't cool as well or have sufficient excess cooling capacity unless you pay top dollar for it.
While many do not like electric fans from what you're saying the Jeep is rolling down the road so even the mechaincal fan technically wouldn't be cooling that much because as I understand it once you're above a certain MPH it's the air flow thru the radiator that is doing the cooling.
No I don't think that having more HP & TQ would be the issue here with your 35" tires. If it wasn't overheating before the SC install which is when you would have been putting more of a strain on the engine and transmission. I am a little curious about your comment when you said you'd pulled over and then when you tried to pull out it wouldn't move until you put it into 4WD. That might indicate the transmission overheating but it doesn't make sense that putting it in 4WD somehow fixed it.
Did you ever figure out how to pull codes on your TJ? Have you tried the key off to key on 3 times and read the codes in the odometer area?
I'm still going back to something with the tune or something else related to the SC install since it wasn't happening prior. As far as how to tell if it's a stock Mopar radiator I thought that there was a sticker on the top but can't remember for sure. And I can't find the picture I'd had of my daughters when her top tank split.
Unfortunately mpvi pro will not work on a 99 TJ I have to upgrade to mpvi 2. Waiting for my upgrade to come in before I can do any logs. I'll post up a log as soon as I get the new unit.
I just upgraded my MPVI 2 to the Pro version to be able to log AFR. Man, HPTuners thinks highly of their upgrades...
Yes they do! I'm assuming since I sent a mpvi pro in they will upgrade it to a mpvi 2 pro
The mechanical fan does more than you think at speed especially if you have added to the cooling stack. I would never replace a working mechanical fan for an electric.
Also do your homework on HP Tuners and forced induction on the TJ. It has significant limitations that have been discussed in detail on the HP tuners forum. I have used Scan XL in the past to data log OBD2 data. It works similarly to HP tuners scanner without spending $600. I would map your air/fuel and spark timing if you have any question about the quality of the tune.
Also do your homework on HP Tuners and forced induction on the TJ. It has significant limitations that have been discussed in detail on the HP tuners forum. I have used Scan XL in the past to data log OBD2 data. It works similarly to HP tuners scanner without spending $600. I would map your air/fuel and spark timing if you have any question about the quality of the tune.
Thank you for helping. I have a supercharger so the mechaincal fan is gone permanently. I already own hp tuners so the upgrade is only $187. I will do some logs when I get my hardware back and post them. Sounds like you may be able to take a look at it and give me your opinion on the tune.
I'm guessing that the mechanical fan gets removed when you install the supercharger? I'm not super familiar with the TJ supercharger setups. You can still log OBD data without the upgrade to Pro. Pro just adds channels for additional sensors like a wideband. You will have to have a wideband controller with the pro. Something like a Innovate or AEM gauge to provide the 0-5v signal for the Pro connection. I would start by setting up some histogram tables that mirror your fuel and timing tables. Then go drive and log. Something like this.
I have been researching the magnum powers kit myself. I think I remembered reading that @David Kishpaugh is a dealer and knows a lot about them. I think he uses an additional fan shroud that doesn’t come with the kit when he installs them for customers. Not sure if that would help or not. If my post count ever gets high enough I will pm him and ask some questions.
What fan are you running?
does it have a shroud?
Is there any pinging?
We have the unichip tune running very well in the 97-04 running magnumpowers chargers. It can obviously be improved for individual cases as needed if we know what it's doing. I'd suggest talking to Tony at unichip USA, he can take care of that.
We struggled hard on 05/06 tunes with unichip. We just could not get it right and have resorted to custom tuning which I'm personally taking care of. One of the issues with the later model was overheating caused by the timing retarded so much to prevent pinging, aside from the pinging, pretty much only at cruise speeds, the unichip tune was putting just shy of 300hp on the dyno. I'll have dyno results from the newest tuning I'm messing with this coming week.
does it have a shroud?
Is there any pinging?
We have the unichip tune running very well in the 97-04 running magnumpowers chargers. It can obviously be improved for individual cases as needed if we know what it's doing. I'd suggest talking to Tony at unichip USA, he can take care of that.
We struggled hard on 05/06 tunes with unichip. We just could not get it right and have resorted to custom tuning which I'm personally taking care of. One of the issues with the later model was overheating caused by the timing retarded so much to prevent pinging, aside from the pinging, pretty much only at cruise speeds, the unichip tune was putting just shy of 300hp on the dyno. I'll have dyno results from the newest tuning I'm messing with this coming week.
Fan looks just like this and it's all I received no shroud.
Currently getting re geared so haven't been able to do any testing. Hopefully have it back next week.
Also glad to hear your having success it's a pretty big investment and hopefully i hit the 300 hp range.
Tldelaney
TJ Enthusiast
pull data from hptuner via a serial connection. You dont need pro. the lancer forums have some good detailed guides on how to do so. I have magnumpowers SC and ARH headers on my LJ, no problems so far.
The fan is a high quality high output SPAL . the overheating is most likely coming from the tune being incorrect. If you are concerned about the fan, barnes makes a shroud for electrical fans that will help direct the air.
The fan is a high quality high output SPAL . the overheating is most likely coming from the tune being incorrect. If you are concerned about the fan, barnes makes a shroud for electrical fans that will help direct the air.
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If it doesn't have a shroud I'd put one one it. It might not be the reason for your overheating issues but IMO you need to have some type of shroud..
Tldelaney
TJ Enthusiast
agreed this was my biggest concern with a 8274 and the sc intercooler up front.. I was going to fabricate one but saw barnes had it. Saved in my cart just in case. The electrical fan gives a huge amount of space up front
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The big problem with those electric fans is most people mount them directly to the radiator core. This means only the area where the fan is mounted gets cooling. Some of the designs are also restrictive when they are not running. All those support bars and blades slow down the airflow at speed. Some of the older designs used flaps that would open when driving on the highway.
I don't know what the cooling needs of SC 4.0 is compared to a V-8 in our TJ's but I didn't have any cooling issues with my V-8 & 8274.
Now my new engine is suppose to have more issues with cooling than my old one did. I'm going to start with my brass radiator first and see how it does and then if it isn't enough then I'll step up to a 3-4 row aluminum radiator.
Back in my younger days I remember fighting with a cooling issue on a CJ5 that I had a electric fan on. It wasn't until I finally put a shroud onto it that I fixed it. And yes I remember those older style fans that had the flaps would open up once up above a set speed.