Radiator Fan not spinning fast, and the reading on the temp gauge

[MN12hybrid]

In the past, I noticed that these Mark fans are very powerful obviously, and that they speed up as needed.

1. My makes a slight squeaky sound, and even when the motor is getting up in the warm range, it doesnt speed up any more. I installed a Mark fan on my 5.0 Tbird years ago, and it seemed like it created a ****ing tornado under the hood it was soo ballsy!

My AC is trashed, so I cant turn it on to check if the fan goes straight to full speed.

When you turn the AC on, is the radiator fan supposed to run full blast, or does it ramp up slowly and only spin at full speed if it really needs the extra cooling?


2. I noticed my car runs warm. I used the search feature and found this was common, but have yet to find an explanation that applies to my situation. The car will sit in the middle while driving, but slowly heat up to where its just above normal and sit there. If you go uphill, or try using more throttle, it climbs higher. I never got the car to overheat, but it went up to the "N" one day last year while going uphill in traffic, and it was 110 degrees out. I checked the temp on the motor with my temp gun and it said 208, when I pulled over.

I noticed my Taurus has a similar gauge (with the "normal" range) and it too, also tends to hang out just above the middle, sometimes a little higher but it doesnt overheat. When I run the AC on that POS car, it cools down to just below the middle, at the bottom of the "normal" range.


What is the normal operating temps for these cars? I have seen many different answers before, and I heard that some years for the Marks, this was a common issue even on a car in great shape with no issues with coolant system and no blown HG's. I am going to fix the AC in my Mark, but I want to get this sorted out first.

When it sits up above the middle range, (in normal range still), is that normal? I think the temp gauge in the Marks, is just trying to show real time info on the temp which is probably why it fluctuates so much - Is this correct? The thing that bothers me so much, is that if I makes to to "N" on the gauge, there is very little room between that and overheating. Does this happen to you guys?

In other cars like my previous MN12's, the temp gauge sits in the middle whether its 180 or 195 - if it heats up more than it goes above the middle. Its just like that in my Accord as well.

I know I mentioned my fan seems to be acting up and Im sure that this would have something probably to do with the temp gauge reading, but I have seen others (others with Marks in MUCH better shape than mine and no fan issues) on here experiencing this.


Thank you in advance!!!

 

[chris2523]

first gen gauges are not wholly accurate. i assume this is your 94 you just posted about?
being in the normal range really is normal.
my 96 runs on the hot side, even more so running AC. no issues. a scan gauge shows all is well too.
the 93 runs on the cold side, even when the ac was running when it worked.

the fan is indeed variable speed, the computer will only command as much fan speed as it needs.
with no AC, the computer probably won't see a need for high speed. the mark's cooling system is quite efficient.

an option is to unplug the two wire temp sensor on the crossover tube, the computer should send the fan to full speed as a temp sender failsafe.

 

[MN12hybrid]

I may try unplugging the sensor on the crossover pipe just like you mentioned, because I am very curious if the fan will move at the same rate of speedvas the one I threw on my Tbird in the past.

What temp do your cars normally run at, and what would be considered a temp where I should start worrying?

It just seemed odd to me that the cooling system is like this with such little room between the upper norm range and overheating.. Especially so
if these motors tend to heat up quickly. Im assuming its what happened with this Mark Ive been stripping parts from today at the wrecking yard
(bad radiator).

Just about every other car Ive had, would run the radiator fans like crazy to keep them in the 195 degree range or little lower.
Do these aluminum intec motors tend to run warmer than most other engines in genera because they are all aluminuml?

Back when my girlfriends Kia was overheating, it would get up to around 210 for a little while (and would get weak) just before. Otherwise it
hovers around 195 - 200 degree range normally. Obviously its a much different car so I dont mean to compare apples to oranges, but I am just
trying to get a better idea.

I do have an OBD scanner - where is the port on these cars? When I start working on the car next week, ill be throwing in new hoses,
coolant overflow tank, and cross over pipe and it will be a perfect time to figure out what the actual temp is with the scanner,
while watching my temp gauge on the dash.

Something else worth mentioning...Early on when I got my Mark, my crossover pipe cap was stuck so I had to improvise while bleeding the system. I stuck 2 bricks under the coolant reservoir (the car on jack stand as well) and bled it through there. Not the best way to do it, but I got the system bled after about 4 hours. Everyone warned me that I could have screwed up the motor so I was worried about that. Shortly after that I busted my radiator, and limped the car home without overheating by traveling downhill fortunately. I had to put in a reman radiator and do the process over again, but the car actually ran cooler with the new radiator, although I still didnt touch the thermostat. Unfortunately I have a ticking sound coming from the top of my motor now that remains after thesound from the timing chain tensioner dissipating. I am going to take a video of this, and post to youtube, and create a new post with this issue if it remains after next week when I work on this.


Thank you for the help and sorry for the long posts! I type very fast, and wanted to get as much info up as I can regarding each of these issues since I am getting everything sorted out, so I will be making some new posts on these other issues. If I can make this Mark a daily driver fun car again, Ill keep it since I have a 99 Accord with only 36k on it (and a beater Taurus as well) to use for the long drives.

 

[chris2523]

on the

N
O
R
M
A
L

gauge, the 93 runs on the A, and the 96 runs on the M and R, sometimes O in the heat with AC.

195 to 200 sounds about right. i think the stock thermostat is a 195?

if the temp gauge ever moves above the N, that is too high, and there is a problem somewhere.
even on the N is a bit hotter then most cars.

maybe you need a new thermostat? i hear stant makes a nice lower temp unit.

and you really should get that crossover cap open.

only 96-98s have an OBD port. its located down by the pedals, on that kick panel down there.

 

[opalescent 96]

Trying to remember all your questions...

obdI diagnostic port would be under the hood.

208 is far from overheating so that's a relief. That's probably where the fan kicks on. Mine stock would be at half gauge then go to the R. The fan comes on then goes back to half. It would go higher sometimes and it freaked me out... I replaced the coolant sensor and that solved it and dropped the fan one point about a letter.

One thing about your story with the temp gun... as soon as you open the hood that is going to drop the temp down, so the temp may have been higher?

The ticking might be a lifter on the 7 or 8 cylinder. Those cylinders especially and the driver side head in general run the hottest coolant temps.

 

[MN12hybrid]

I ended up drilling into the crossover cap with a drill press and threaded in a bolt. What a major pain in the ass I might add..

I have a crossover pipe now sitting aside that looks like its next to brand new, with a good cap thats not stuck, and good seals.

So all the new hoses I get on, I really should be using a new thermostat to be safe.

Are the 170 degree Cobra ones ok to use, or should I use one of these 180 degree Stant models? I know you cant go below 180 on most cars,
but I was pointed towards the 170 in the past and told it would be ok with stock computer.

It also just occured to me that their is a trans cooler on the bottom of this radiator as well. I am thinking about getting the power steering cooler
from the wrecking yard, flushing it and mounting it to my car to cool my transmission. It would probably make the existing setup also work better.

Does your 93 ever get warm like the others, or is it in the range you mentioned constantly even on a very hot day?

What scanner will I be able to use with my 94 Mark?

 

[MN12hybrid]

Sorry - I posted my last one before I noticed another response!

When I turn off my car, I hear a loud cracking or creaking sound that sounds like metal is flexing. It sounds like a hammer tapping on hollow metal once or twice.

It does it while the car is on when warming it up but pretty much stops when it gets warm. Its mostly when the car is off and cooling down. I have heard cat converters do this in the past, but not this intense. When I get video of my car running next week, Ill try to include this in there as well.

Is that just a characteristic of these aluminum motors?


Great responses so far - Thank you guys! The new posts I make over the remainder of this week will be a little redundant, but I want to
collect as much info as I can, so I can be armed with it when I really dig into the car. Every time I worked on the car in the past it had to be done
with the fact in mind that its a daily driver and needs to be completed, or else. Now that I dont have to depend on my Mark right now, it will take
a lot of the stress out of working on this beast; it may actually be fun!

 

[sprocket]

I run a 180 Stant and the temp sits on the A most of the time. It can climb in stop and go with the A/C running and high outside temps but it still seldom gets past the middle of the R.

 

[chris2523]

Does your 93 ever get warm like the others, or is it in the range you mentioned constantly even on a very hot day?

that temp is pretty constant, it never raises above the middle.

nothing wrong with a 180 thermostat, or even a 160 really. 180 is fine for most people.

When I turn off my car, I hear a loud cracking or creaking sound that sounds like metal is flexing. It sounds like a hammer tapping on hollow metal once or twice.

uhhh, nope. that doesn't sound good.

 

[jbelcourt]

Mine also does that. It's always does that. I'm quite certain is the exhaust, fyi.

As for temp, my 93 does EXACTLY what Chris' 96 does temp wise.

 

[opalescent 96]

The crackling sound probably exhaust heat shied or something. You need a obdI Ford code reader: check ebay... or some guys use a paper clip or something?

I don't know about a pwr steering cooler for the transmission, would think that would be rather small.
This is the write up that I followed, b&m cooler:http://www.markviii.org/LOD2/trans_cooler.htm

 

[jbelcourt]

The crackling sound probably exhaust heat shied or something. You need a obdI Ford code reader: check ebay... or some guys use a paper clip or something?

I don't know about a pwr steering cooler for the transmission, would think that would be rather small.
This is the write up that I followed, b&m cooler:http://www.markviii.org/LOD2/trans_cooler.htm

I was thinking heat shield as well. Like I said, mine does that.

Also, as for an ODB I scanner. O'Reilly sells a pretty decent Ford/Lincoln/Mercury specific one and it wasn't very expensive. I bought one a few months back.

EDIT-

This is the one I bought:

http://www.oreillyauto.com/site/c/d...4_4579&keyword=code+reader&pt=N0664&ppt=C0103

 

[opalescent 96]

^^^^^ That's fancy. The one I have just has a blinking light and beeps. No readout. Comes with a book.

 

[Stangman]

first gen gauges are not wholly accurate. i assume this is your 94 you just posted about?
being in the normal range really is normal.
my 96 runs on the hot side, even more so running AC. no issues. a scan gauge shows all is well too.
the 93 runs on the cold side, even when the ac was running when it worked.

the fan is indeed variable speed, the computer will only command as much fan speed as it needs.
with no AC, the computer probably won't see a need for high speed. the mark's cooling system is quite efficient.

an option is to unplug the two wire temp sensor on the crossover tube, the computer should send the fan to full speed as a temp sender failsafe.

my '93 was the opposite of your '93. Ran warm (but took forever to get there) and ran really warm w/ the A/C on. And if I flogged on it, the car got warmer. But cooled of quick. So I dont think it was a head gasket or anything. Although, after I wrecked I noticed it STILL had the original brass/copper radiator in it. I replaced it when I rebuilt it w/ an aluminum/plastic rad, but It's being replaced w/ an all aluminum rad of course

 

[MN12hybrid]

The crackling sound probably exhaust heat shied or something. You need a obdI Ford code reader: check ebay... or some guys use a paper clip or something?

I don't know about a pwr steering cooler for the transmission, would think that would be rather small.
This is the write up that I followed, b&m cooler:http://www.markviii.org/LOD2/trans_cooler.htm

Just checked the write up and its mounted in the same spot I had in mind

I do have a gigantic Hayden trans cooler that I got back in the day for my Tbird that I was going to use with a thermostat so the trans would be able to heat up properly. The problem is that I overdid it.. lol.. it belongs on a motor home... Its probably 2 to 2.5 times the size of the one in the write up.. lol

 

[MN12hybrid]

At what temp do these motors need to be running at to be considered "officially overheating?"

I was always curious about that because of these motors being aluminum...

 

[Kahmael]

Hello, I myself am a new Mark owner. I have a 94 that after a lot of coolant system work, I am experiencing the same issue as you. In my case, i have a new all aluminum radiator and water pump. Currently, I am not running a Tstat. I have seen the same issues that you do. Driving around town and climbing hills the car heats up from M to R but so far never to O. When I'm on the highway at night the temp gauge reports A, but soon as the car slows down to around town speeds the temp gauge creeps back up. I have pulled over and checked to see if the fan is pulling and It seems to be pulling strongly, the air is very hot but that would indicate it wasn't the VRCM.

Before I replaced the waterpump, old tstat, and radiator my car never moved above M but stayed around A and L. Is my issue an indication of air in the system?

 

[mark0101]

Hello, I myself am a new Mark owner. I have a 94 that after a lot of coolant system work, I am experiencing the same issue as you. In my case, i have a new all aluminum radiator and water pump. Currently, I am not running a Tstat. I have seen the same issues that you do. Driving around town and climbing hills the car heats up from M to R but so far never to O. When I'm on the highway at night the temp gauge reports A, but soon as the car slows down to around town speeds the temp gauge creeps back up. I have pulled over and checked to see if the fan is pulling and It seems to be pulling strongly, the air is very hot but that would indicate it wasn't the VRCM.

Before I replaced the waterpump, old tstat, and radiator my car never moved above M but stayed around A and L. Is my issue an indication of air in the system?

It maybe air in your system since you did do all your cooling recently. I just went through my car overheating and bleeding your system from the cross over tube is at least one variable out of the equation to see what could be your problem. As long as your bolt isn't stuck, it is easy to get that out of the way, plus make sure it's not leaking anywhere and introducing air from there. But like it has been said, you probably don't need to worry as long as it's not overheating.

 

[Kahmael]

Thank you for the reply, I did fill the coolant from the crossover tube plug, and I've not noticed any more coolant leaking. When you burp the car, what is the process? leave the crossover plug off and let the car run? I've done that but eventually it will shoot out of the crossover plug hole.

 

[mark0101]

Thank you for the reply, I did fill the coolant from the crossover tube plug, and I've not noticed any more coolant leaking. When you burp the car, what is the process? leave the crossover plug off and let the car run? I've done that but eventually it will shoot out of the crossover plug hole.

Yeah, that's it. You should be good and I wouldn't worry to much about it.

 

[MN12hybrid]

I actually still have the OEM sticker under the hood stating the bleeding process, and its surpsiring because of the mileage with my Mark. Bleeding makes all the difference in the world, since these are what Ive determined to be finnicky (at times) motors that are sensitive to air bubbles. But on the other hand I was very use to my 93 Tbird 302 - it was so simple compared to this motor. All maintenance, even mods were applied easier. Bleeding was simple and once you got the air out, it was out unless there was a very large leak. In fact, I think my Tbird 5.0 didnt even have a vent plug and did it through radiator. My 92 3.8 LX slug on other hand did have then vent plug. Overall these Mark motors were way ahead of their time and I get the feeling if I start really putting effort into mine (even with 240k), my Mark can be a reliable daily driver again if I wanted to (I do have a beater). Major leaks on my motor and trans are being addressed now, but its still never burned through more than a quart per oil change. Im redoing all the lines and the ac lines. Im currently redoing all the vacuum lines on my motor and its already making a huge difference (combined with spay Seafoam) with the way its running! I am also addressing the AC because its hot in LA, and I have migraine issues that only get worse from the excessive heat experienced in a hot car even with the windows down. It seems like everything has to be done to my Mark, but instead of replacing it with a lower mileage Mark, I decided to just restore mine slowly and enjoy the process like I did with my Tbirds. In the end, Ill have my Mark built exactly how I wanted with a rebuilt, blueprinted (and enlarged to 5.0) motor and trans by 300k - or less if my motor dies before then. When you go so far to restore a car you love, the mileage is just a number at that point.

I sure do have my work cut out for me though!

 

[opalescent 96]

I have parked mine nose up on an incline with the engine warmed up and running. I crack my crossover plug and got a few more bubbles out but don't open it too much cause then you can introduce air. Also kind of risky because the force of the coolant can bust the O-ring on the plug so it's good to have another O-ring on hand.

When you fill it for the first time, you want to fill it to the top cold and allow time for it to settle then fill a little more. Cap it, drive around and let it warm up. Then you park it overnight. Open the cap and fill it up to the top again because it won't be to the top, believe me. Then see above

 

[BigredLsc]

I actually still have the OEM sticker under the hood stating the bleeding process, and its surpsiring because of the mileage with my Mark. Bleeding makes all the difference in the world, since these are what Ive determined to be finnicky (at times) motors that are sensitive to air bubbles. But on the other hand I was very use to my 93 Tbird 302 - it was so simple compared to this motor. All maintenance, even mods were applied easier. Bleeding was simple and once you got the air out, it was out unless there was a very large leak. In fact, I think my Tbird 5.0 didnt even have a vent plug and did it through radiator. My 92 3.8 LX slug on other hand did have then vent plug. Overall these Mark motors were way ahead of their time and I get the feeling if I start really putting effort into mine (even with 240k), my Mark can be a reliable daily driver again if I wanted to (I do have a beater). Major leaks on my motor and trans are being addressed now, but its still never burned through more than a quart per oil change. Im redoing all the lines and the ac lines. Im currently redoing all the vacuum lines on my motor and its already making a huge difference (combined with spay Seafoam) with the way its running! I am also addressing the AC because its hot in LA, and I have migraine issues that only get worse from the excessive heat experienced in a hot car even with the windows down. It seems like everything has to be done to my Mark, but instead of replacing it with a lower mileage Mark, I decided to just restore mine slowly and enjoy the process like I did with my Tbirds. In the end, Ill have my Mark built exactly how I wanted with a rebuilt, blueprinted (and enlarged to 5.0) motor and trans by 300k - or less if my motor dies before then. When you go so far to restore a car you love, the mileage is just a number at that point.

I sure do have my work cut out for me though!

Wow I’m in la too could use some help lol marks definitely a keeper

 

[xtriggerman]

Another place to find unwanted air that no one ever mentions is the top heater core pipe. Even with no issues, your bound to have air trapped in that pipe if you had the system opened up like I did as a replaced radiator. The fix is fit a funnel to a straw, pull the top hose 95 percent off the heater core but leave a slight opening at the top edge of the hose, put the straw in there and slowly fill it with coolant until it over flows and at that moment push the hose on and pull the straw out of the way. My temp gauge stays slightly below half no matter how the car is run.

 

[BigredLsc]

Another place to find unwanted air that no one ever mentions is the top heater core pipe. Even with no issues, your bound to have air trapped in that pipe if you had the system opened up like I did as a replaced radiator. The fix is fit a funnel to a straw, pull the top hose 95 percent off the heater core but leave a slight opening at the top edge of the hose, put the straw in there and slowly fill it with coolant until it over flows and at that moment push the hose on and pull the straw out of the way. My temp gauge stays slightly below half no matter how the car is run.

Sick advice thanks bro