Results 1 to 8 of 8

Thread: Water temperature gauge in M52B28 engine

  1. #1
    Join Date
    Dec 2018
    Location
    Indonesia
    Posts
    109
    My Cars
    E30 318i

    Water temperature gauge in M52B28 engine

    Hi guys,

    I'm planning to install additional water temperature gauge in my M52B28 swapped E30. I have purchased the gauge, it's a VDO unit 52mm.

    Where should I tap the sender into to get an accurate reading? I have tried searching in the forum but I couldn't find definitive answers. Either opinions or suggestions. Has anyone done this before in an M52 engines? Mind sharing some photos and reviews?

    Sent from my SM-P205 using Tapatalk

  2. #2
    Join Date
    Jan 2008
    Location
    Arida Zona
    Posts
    30,108
    My Cars
    z3
    There are empty ports in the engine head you can tap for a coolant temp sensor. Remove intake manifold and theyll be visible. If not pre-drilled and plugged youll usually want to remove head to tap for the fitting

    Going into my TENTH YEAR of providing high quality reproduction BMW fabrics!

    PRICE CUT on ALL FABRICS
    Offering the best prices on the best quality reproduction fabrics!

  3. #3
    Join Date
    Nov 2016
    Location
    Long Island, NY
    Posts
    332
    My Cars
    A few
    You can also use the throttle body coolant lines as a coolant temperature sender source.

  4. #4
    Join Date
    Dec 2018
    Location
    Indonesia
    Posts
    109
    My Cars
    E30 318i
    Quote Originally Posted by R.Thomas View Post
    You can also use the throttle body coolant lines as a coolant temperature sender source.
    Thanks for the suggestion. I'm considering this one too since it is sort of easier to get to. But what I dont know it whether this port has constant coolant flow and whether the reading would be accurate

    Sent from my SM-N770F using Tapatalk

  5. #5
    Join Date
    Jun 2003
    Location
    San Jose, CA
    Posts
    361
    My Cars
    '02 M Coupe, '12 C4 GTS
    Quote Originally Posted by Leon.stt View Post
    Thanks for the suggestion. I'm considering this one too since it is sort of easier to get to. But what I dont know it whether this port has constant coolant flow and whether the reading would be accurate
    It depends on what you mean by "accurate". Your engine isn't all one temperature; different parts are at different temperatures. The sensors in the head are close to where things are the hottest, so they're in a good place to tell you the worst. Sensors further away, less so. Definitely recommend using those ports.
    '02 M Coupe

  6. #6
    Join Date
    May 2017
    Location
    Owings, Md
    Posts
    1,105
    My Cars
    1998 328i
    Quote Originally Posted by R.Thomas View Post
    You can also use the throttle body coolant lines as a coolant temperature sender source.
    The coolant circuit for the throttle body is connected to the head by a nipple that screws into the head, same thread as the stock temp sensor. As long as you cap the other end of the line, you can unscrew this nipple and insert your temp sensor there and it will be at the same temp as the stock sensor, 3 cm away. It is straight threaded and uses a crush washer to make the seal rather than using tapered threads.

    The M50 heads had three ports because there were two different temp sensors, one to the computer and another to the dash. The last fed the throttle body circuit. Early m52's had 3 ports but one was capped off, probably leftover heads from m50 production.

    The throttle body preheat circuit is totally unnecessary unless you are trying to prevent intake icing in the arctic. I capped mine where it attaches to the metal coolant line that runs underneath the intake manifold.
    Last edited by gdavid; 10-06-2020 at 03:33 PM.

  7. #7
    Join Date
    Jan 2008
    Location
    Arida Zona
    Posts
    30,108
    My Cars
    z3
    Quote Originally Posted by gdavid View Post
    The coolant circuit for the throttle body is connected to the head by a nipple that screws into the head, same thread as the stock temp sensor. As long as you cap the other end of the line, you can unscrew this nipple and insert your temp sensor there and it will be at the same temp as the stock sensor, 3 cm away. It is straight threaded and uses a crush washer to make the seal rather than using tapered threads.

    The M50 heads had three ports because there were two different temp sensors, one to the computer and another to the dash. The last fed the throttle body circuit. Early m52's had 3 ports but one was capped off, probably leftover heads from m50 production.

    The throttle body preheat circuit is totally unnecessary unless you are trying to prevent intake icing in the arctic. I capped mine where it attaches to the metal coolant line that runs underneath the intake manifold.
    The TB coolant loop feeds off the metal coolant pipe - it does not feed into the head itself

    Going into my TENTH YEAR of providing high quality reproduction BMW fabrics!

    PRICE CUT on ALL FABRICS
    Offering the best prices on the best quality reproduction fabrics!

  8. #8
    Join Date
    May 2017
    Location
    Owings, Md
    Posts
    1,105
    My Cars
    1998 328i
    Quote Originally Posted by BimmerBreaker View Post
    The TB coolant loop feeds off the metal coolant pipe - it does not feed into the head itself
    The throttle body circuit is connected at two places, ultimately one end connects to the nipple into the head and the other connects to the metal coolant pipe, in some applications, there is a thermostat that is also in line to stop the flow. None of it is necissary unless you drive in the arctic but you need to ensure that both ends are capped off so avoid a leak. I have no idea which direction it flows.

Similar Threads

  1. VDO 2.125" Water Water Temperature Gauge w/ Gauge Pod - $40
    By markseven in forum Car Audio & Electronics
    Replies: 0
    Last Post: 11-18-2012, 10:25 PM
  2. Equus 2.125" Water Temperature Gauge w/ Mounting Plate - $20
    By markseven in forum Car Audio & Electronics
    Replies: 0
    Last Post: 11-18-2012, 10:22 PM
  3. Replies: 0
    Last Post: 07-31-2012, 01:34 AM
  4. WTB: VDO Water Temperature Gauge with Sending unit......
    By AvusBlau//M3 in forum BMW Parts Wanted
    Replies: 0
    Last Post: 07-30-2012, 05:13 PM
  5. Water temperature gauge readings higher than normal...
    By LeMansGTS in forum Forced Induction
    Replies: 4
    Last Post: 03-08-2008, 07:29 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •