Running hot after changing head.

[2gGst98]

So I just swapped my head recently, ever since I have been running hot.

Problems I have found thus far,
1 didn't bleed properly first time,
2 fan wouldn't come on
3 coolant cap not holding pressure,

Now I have fixed all three of these problems but I seem to be still running hot. My needle is 3/4 -2/3 of the way up. Log said 205-215*f. My hoses now get pressurized I now feel my lower radiator hose was not as hot as lower one.

I will be changing out to a 160*f t-stat but any other ideas would help.

I did put on a front mount, my bumper is not on, and I am tracking down a boost leak. Boost leak will be fixed this weekend, does the bumper matter? I read somewhere if air isn't going through the cowl then air is going around radiator and could cause hotter temps I don't no about this but I read it in one of the many post before I posted this.

 

[johneclipse]

Having your bumper cover on/off shouldn't matter. I would burp the system again. And check if your head gasket is allowing exhaust into the coolant.

 

[talon77]

I see on your avatar pic that you don't have any of your heat shields on either your exhaust manifold or your o2 housing. Those help to keep the underhood temps under control, and reradiating back to radiator. I would put those shields back on or fab new ones. That, combined with your new FMIC addition might have resulted in the new found heat rise you are experiencing.

Also, if you want to find out if your combustion chambers are leaking into your coolant, then do a leak down test with compressed air. When you pressurize your cylinders, if you get bubbles in your coolant, then you know you have a leak between your combustion chamber and your coolant passage.

As for the bumper (I assume you mean bumper cover), if anything, the lack of a bumper is keeping your temps down because some air has a straight shot to your radiator instead of having to go through that FMIC. (If the 2gs are set up anything like a 1g).

 

[2gGst98]

Thanks yea I will be doing a leak down test this weekend. I figured that with the bumper cover off would be better, had to ask 'cause of what I read. I'll have to steel my heat shield back from my buddy.

Tomorrow - I will be re burping the system, putting in lower temp t-stat in to make sure it will open fully, and leak down test. Anything else you guys app an think of. Might switch from 50/50 to 100% distiller water for summer any thoughts on that. I was told that only water is better than 5050 not 100% on that though though.

I'm still reading / researching, all in all it's saying to put in a 160* t-stat and water wetter in mix.

Thanks yea I will be doing a leak down test this weekend. I figured that with the bumper cover off would be better, had to ask 'cause of what I read. I'll have to steel my heat shield back from my buddy.

Tomorrow - I will be re burping the system, putting in lower temp t-stat in to make sure it will open fully, and leak down test. Anything else you guys app an think of. Might switch from 50/50 to 100% distiller water for summer any thoughts on that. I was told that only water is better than 5050 not 100% on that though though.

I'm still reading / researching, all in all it's saying to put in a 160* t-stat and water wetter in mix.

 

[BogusSVO]

First off, 205-215* Is not running hot.

You are right about where you want to be.

The boiling point for water at sea level is 212*

No for every pound of pressure the rad cap holds allows you 3* above boiling point

Most DSM have a 13lb rad cap

So the math is this...

(13 x 3*)+212 = boil point

39* + 212* = 251*

Also a 160* thermostat will not have you run cooler, it just opens up sooner.

So on shortish drives, you may think you are cooler due to the 'stat opening sooner, but drive long enough and you will get back up to the 210 range.

Also a cooler block wears faster than a hot block.

You will also get better fuel mileage running warmer than cooler.

 

[2gGst98]

Well my needle is in between 3/4 - almost all the way up. At that time my log is at 205-225 used to be 190-200. I wouldn't think my front mount would play that much into it with my bumper cover off. My heat shields have always been off and never caused a problem before, but I might just put them back on. I mainly want a lower temp t-stat, 'cause I think mine is out of sack anyway, and just to burp it at lower temp, mine seems to keep closing when I try to burp it. Then gets hot but doesn't seem to overheat.

I will be looking into it tomorrow more when I'm off work.

So I pulled another log and found I am hotter the than what I said before. Needle is Sam place 3/4- almost all the way up, but I'm upwards of 225 them it will spike and stay at 363*f I think it hits an air pocket! but I bleed the system for 40 min the other day. I am missing something, I appreciate the help.

I am going to out in a lower temp t-stat to burp it quicker, and put in straight distiller water. We will see what happens

Follow up,

I re blead the system, it ran for 30-45 min after it got warm. What it does is needle goes almost all the way up, then fan turns on and temp goes to the middle. Had the cap off you can see the t-stat open and coolant flow, their seems to be no air in the system. My comp won't connect to Ecu for some reason so I can't tell exact temp numbers.

Is their a right or wrong coolant to use? Not sure if that is a dumb questions or not. Also can I install the t-stat wrong? I'm mechanically compatant I or at least I like to think so. I would think I wouldn't do that but never no.

 

[2gGst98]

So I found out what it was. I had 2 bad ground wires, one of witch was completely broke. Must have broke during the install some how, the other on was hanging by just a few strands of wire. Got them all soldered up and connected, now running between 196-209 needle stayed in the middle at idle for an hour.

Why would bad connections do that? My step dad told me to look for bad connections. And I found those, fixed them and now it runs good. I do hear a boost leak though tomorrow is another day. Thank guys

 

[lil corb]

Glad you got that fixed but that is interesting the grounds would do that.