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3800SC - no heat - no coolant flow to heater core by gtoformula
Started on: 12-14-2013 05:08 PM
Replies: 11 (679 views)
Last post by: gtoformula on 12-27-2013 05:07 PM
gtoformula
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Report this Post12-14-2013 05:08 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
The car is a 1986 GT with a 1997 Regal 3800SC and 5spd Getrag. Interior heat hasn't been an issue in Texas until recently ... we got 3-4" of ice and temps into the high teens/low 20's. I know that's not much for you northern guys (I was a northern guy years ago), but no heater isn't fun in the winter. I've been crawling about the engine bay and under the car to trace the coolant lines and think that the original install is probably the issue. Looking for input and/or confirmation. I had a few drips from the heater core and just replaced that, but there was no coolant in the lines. I hijacked a couple of images from an archived thread (hope that's OK) and have posted them for reference. Great images ... I couldn't do better so reusing them. I previewed the images and they may not appear in my thread, but you can use the link I included to pull them up.
The pics are not of my car ... just for reference. I have a low mount alternator so the coolant flow out the alternator mount is not an option for me.
Here is the link to the original thread.
https://www.fiero.nl/forum/A...100421-2-092990.html

A heater hose comes straight out of where the yellow #1 points to in this pic and pointed directly at the passenger side frame rail. It is then connected to a ninety degree bend and runs down to one of the coolant tubes that route up front to the heater core. There is no connection where the yellow #2 arrow points to the area below the supercharger. It just has a freeze plug in that port.
The other heater core tube has a hose that routes into the "T" connection at the rear of the coolant tube that runs to the radiator.


This is a better pic of where the freeze plug is installed in the yellow #2 connection. No flow from here.


From what Dennis LaGrua states in his reply to the original post the coolant flow comes from the yellow #2 intake manifold port, flows through the tubes and heater core and then returns to the yellow #1 location. Is my issue that the coolant flow is not directed by the water pump? If location #1 is a return point and the other coolant system location is in the passenger side coolant tube perhaps there is no way for the coolant to flow under pressure. Just a coolant system loop that has no flow?
Thanks in advance for any insight that you can provide.
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phonedawgz
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Report this Post12-14-2013 05:56 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Pix aren't working
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gtoformula
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Report this Post12-14-2013 06:28 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
I copied them as .jpg's from the original post and was able to save them in my files. I used PIP, but they didn't come out when I posted them. Not sure what the problem may be. I could take my own pics, but with all the wiring around the photo area they wouldn't come out very well. If you are able to open the link to the original thread you should be able to reference my attachment points. I'll work on reposting the pics.
Thanks
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olejoedad
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Report this Post12-14-2013 08:27 PM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
That routing wont work, both lines are hooked to the suction side of the pump.

Move the line hooked to #1 to the #2 position by removing the elbow from the LIM and putting a nipple in the LIM.
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gtoformula
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Report this Post12-14-2013 10:49 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
olejoedad,
Thanks for the reply ... you've confirmed my thoughts regarding the basic flaw in how my set up was installed. What is the definition of LIM? Sorry, just don't recall that acronym. Also, I assume that the ports for #1 and #2 are not threaded? What type of plug do I need to install in #1? What type of nipple will I be installing in #2?
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Big Paul
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Report this Post12-14-2013 11:11 PM Click Here to See the Profile for Big PaulSend a Private Message to Big PaulEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by gtoformula:

olejoedad,
Thanks for the reply ... you've confirmed my thoughts regarding the basic flaw in how my set up was installed. What is the definition of LIM? Sorry, just don't recall that acronym. Also, I assume that the ports for #1 and #2 are not threaded? What type of plug do I need to install in #1? What type of nipple will I be installing in #2?


LIM = Lower Intake Manifold
UIM = Upper Intake Manifold

I cannot see your pictures on my computer, so I can't answer your other questions. Not saying that I would know the answers anyways haha!
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olejoedad
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Report this Post12-15-2013 08:31 AM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
The two ports can be tapped for pipe threads without drilling. Plug the port on the casting and put a nipple in the LIM.
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gtoformula
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Report this Post12-15-2013 11:59 AM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks again for the replies. I could remove the freeze plug that is in the LIM, but that area is already fairly "busy" with wiring and fuel lines. I found another thread that has an image in the third entry showing a thermostat housing that had been modified to add a coolant nipple. I have a different, but similar, thermostat neck on my set up (tried to post the image, but PIP doesn't seem to be working). For my set up, the stock 3800 thermostat housing is on the engine with a short radiator hose leading to the filler tube/cap assembly. This is a long tube that extends down to the driver's side coolant tubing. I could weld in a nipple somewhere along this tube and attach a heater hose that would go to the heater core tubing. Would that work?

https://www.fiero.nl/forum/Forum2/HTML/126405.html

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olejoedad
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Report this Post12-15-2013 12:03 PM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Several solutions are available to you now that you know what the problem is.

The method I described is very easy to accomplish with drivetrain in the car, probably only a few hours of work involved.
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gtoformula
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Report this Post12-24-2013 01:02 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
Having PIP difficulty

[This message has been edited by gtoformula (edited 12-24-2013).]

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gtoformula
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Report this Post12-24-2013 01:33 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post

gtoformula

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OK. So I've been working on this issue way too long. I've replaced the passenger side heater hose that connects the heater tube to the radiator coolant tube. I've removed the coolant filler assembly and soldered in a tube to attached the heater supply hose. I've replaced the lower radiator hose at the rear of the driver's side radiator coolant tube and also the short section between the filler tube and the thermostat housing. I removed all the heater hoses and coolant tubes and flushed them out to ensure that they are not plugged. I replaced the heater core (it was leaking anyway). After all this I still have no coolant flow to the heater core ... and no heat. Maybe I should just accept that this will be a summer only car and get the AC repaired. I don't know what I'm doing wrong, but I've put a lot of time into this without and improvement. olejoedad recommended that I tap the LIM below the supercharger and install a pipe thread fitting in that location, but I've already got fuel lines and injector wiring in that area. It could be done, but it would be a tight fit. I'm also not too confident about tapping that hole as I fear I might mess up the threading (there is a freeze plug in there now). Please view my Photo Bucket images (also having problems with PIP) and let me know if I've routed something incorrectly. Please!!

Coolant filler tube connects directly to the thermostat housing. I soldered in a supply fitting down lower on this tube.
http://s463.photobucket.com...recent]=1&sort=1&o=0

I discovered that the original heater hose was still on the car (had the crimp style connector at the coolant tube) so I replaced that for insurance. It attaches to one of the coolant tubes that run up front to the heater core.
http://s463.photobucket.com...recent]=1&sort=1&o=2

This is where I installed the supply hose fitting further down the coolant filler tube.
http://s463.photobucket.com...recent]=1&sort=1&o=3

This is where the heater hose from the coolant filler tube fitting attaches to the supply tube running up front to the heater core.
http://s463.photobucket.com...recent]=1&sort=1&o=1
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gtoformula
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Report this Post12-27-2013 05:07 PM Click Here to See the Profile for gtoformulaSend a Private Message to gtoformulaEdit/Delete MessageReply w/QuoteDirect Link to This Post
All is well and the system is routed correctly. Turns out that it is necessary to drive the car after making repairs. Go figure. I only started it, let it warm up and felt the heater hose tubes. They stayed cold while the main coolant tubes and radiator hoses would heat up. Perhaps it needed higher RPM to move the coolant through the heater core. Took it out for a shake down run today and it kicks out plenty of heat. Yay!! Too bad I went stupid and didn't try this before.
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