Heating problems | FerrariChat
Buy

Heating problems

Discussion in 'Technical Q&A' started by robje1355, Oct 5, 2004.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. robje1355

    robje1355 Karting

    Jun 2, 2004
    61
    Netherlands
    Full Name:
    Robert Ercevic
    #1 robje1355, Oct 5, 2004
    The issue is with a Testarossa '87. When driving it the water temp does not go over the 90degrees (celcius) doesn't matter how fast you drive it. However the moment I switch on the heater in the car the water tempreature goes up 5 or more degrees. Coming to a trafficlight (standing still) the temp will run up immidiately.
    If I switch off the heater and get do the same again 10 minutes later the temp stays the same.

    Anybody have anybright ideas what this is or what's causing it?
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,932
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Oct 6, 2004
    Can you clarify the "10 minutes later the temp stays the same" part? Does that mean:

    1. When you do it again 10 minutes later the same bad temperature behavior occurs in the same way, or

    2. 10 minutes later when you switch on again, the temp does not increase and everything is OK?

    Is the 5 deg C jump on the gauge literally instantaneous when you depress the push button or does it take a few minutes to build up?

    The easiest first thing to do is make sure that the coolant system is full & bled. The bleed screw on the large tubing loop on the RH side is fairly easy to access (Item 7 in Fig 40 page 59 of the OM) -- you might try cracking that one open to confirm no air is present as a quicky check (i.e., coolant should leak out immediately when opened 1/2~1 turn). If air is present then you'd probably want to also do the bleed screws on the LH side and the thermostat housing, but, if no air, it's probably not the problem -- just a thought as a place to start...
     
  3. robje1355

    robje1355 Karting

    Jun 2, 2004
    61
    Netherlands
    Full Name:
    Robert Ercevic
    #3 robje1355, Oct 6, 2004
    Hi 91TR

    the 10 minutes later mean:

    I do the same routine again however this time I do not switch on the the heater (same run same drive etc).

    I have bled the system of course and checked the fluid levels also.
    Checked the air bleeding screw already fluid camme out (no air)

    After driving the car for 30 min I switch off the engine and I can almost immidiatly open the cap of the coolant reservoir ( so NO leaking gaskets in cylinder heads)

    Running out of ideas...
    Have been thinking about thermostat but that can't be the problem. Wondering thermostat for the heater is that mechanical or electric? could it be that it is a electric (mass = negative) problem?
     
  4. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
    37,288
    Cowboy Capitol of the World
    Full Name:
    Brian Crall
    #4 Rifledriver, Oct 6, 2004
    The heater valve is electric but it has a plastic body so I don't think it could have any connection. I agree with what 91tr said about bleeding the cooling sys, but at this point I think I would bleed all three points just to put that behind me. Also, I did not understand what you said about the temp at idle. Does it overheat or go up at idle? How high? And with A/C on or off?
     
  5. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,932
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #5 Steve Magnusson, Oct 6, 2004
    Even if the heater valve is malfunctioning horribly, I don't see how this can cause your problem (i.e., the engine cooling should work correctly whether the heater valve is open or closed or anything in-between).

    How about my other question -- do you get an immediate change on the water temp gauge when you turn on the AC/heater or does it take a few minutes to rise?

    And how about something like turning the AC/heater on is such a huge current draw (and it is huge) that for some reason it causes the radiator fans to not work -- have you verified that the radiator fans are actually running when you are having the problem?
     
  6. robje1355

    robje1355 Karting

    Jun 2, 2004
    61
    Netherlands
    Full Name:
    Robert Ercevic
    #6 robje1355, Oct 7, 2004
    Hi Guys,

    A: Well the thing is that the heater is working (not always but most fo the times) I requires some checking this winter anyway.

    Q: How about my other question -- do you get an immediate change on the water temp gauge when you turn on the AC/heater or does it take a few minutes to rise?
    A: I don't get an immidiate reaction, takes a couple of minutes


    Q: And how about something like turning the AC/heater on is such a huge current draw (and it is huge) that for some reason it causes the radiator fans to not work -- have you verified that the radiator fans are actually running when you are having the problem?
    A: Well been thinking about that too... Fans are running alright. Din't have this problem whole summer just last couiple of days this seems to be creeping up. Been driving close to 10.000km this year

    Youi mentioned bleeding the system on all 3 points... have found 1 so far where are the other 2

    Thanks in advance
     
  7. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,932
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #7 Steve Magnusson, Oct 7, 2004
    1 -- top of thermostat housing facing towards the rear and angled up a bit (looks like just a standard 10 mm hex head bolt but it's threaded portion is internal drilled and cross-drilled)
    2 -- RH side towards the front of the engine bay at top of RH tubing "loop"
    3 -- LH side towards the front of the engine bay at top of LH tubing "loop" (this is on the outboard side of one of the upper frame members and sort of under the gas filler neck so it's harder to find than the RH one -- try standing by the LH rear wheel and looking/reaching in rather than standing at the back of the car).

    PS The non-immediate response of the water temp gauge rules out any electrical gremlins in the gauge circuitry itself IMO
     
  8. robje1355

    robje1355 Karting

    Jun 2, 2004
    61
    Netherlands
    Full Name:
    Robert Ercevic
    #8 robje1355, Oct 7, 2004
    91TR,

    Found them afternoon, after typing "where are they?" I went into the garage to find them.. After taking out the engine for belts I felt a bit stupid going "there are three?"

    The electrical part I dissmissed more or less also. They only 2 things left are thermostat or air in the system. Been thinking btw. Whole summer I haven't been using the heater........ So the possible air is/was in the heater part.

    Will be going after this first and will let you know about the outcome.

    1 more thing radiators are getting hot. fans switch on together.
     
  9. robje1355

    robje1355 Karting

    Jun 2, 2004
    61
    Netherlands
    Full Name:
    Robert Ercevic
    #9 robje1355, Oct 7, 2004
    Ok both air bleeds for the radiators gave cooling liquid immidiatly. The bleed in the middle.... well had to remove it completely. started the engine and waited for liquid to come out too. (there was air in the system)
    Stoped engine, put screw back in, started engine again and waited for more liquid to come out.

    Drove again. situation is improved but not 100% yet. Will go after it some more. Def. not thermostat. Did notice that switching on lights has some minor effect on the temp. gauge (switch lights on, temp is a little higher, switch it off lower) etc.

    Driving to the local hardware shop. (3 miles away) av. speed 50Mph. gettin there fans already running. Temp outside 16degrees Celcius (don't know what that is in F).

    Radiators are (i think) original (17 years old now, they might need replacing.)
    Does anyone know as from what year they started using aluminium radiators?
     

Share This Page