Announcement

Collapse
No announcement yet.

College student's m42 repair

Collapse
X
Collapse
 
  • Page of 2
  • Filter
  • Time
  • Show
Clear All
new posts
Previous 1 2 template Next
    #1

    College student's m42 repair

    Hellooooo r3v, it's been a while since I have been on. Last time I was here I completed a timing system overhaul with new sprockets and chain and all, also did the suspension with a new power steering rack and lines.

    My e30 is slightly overheating past the midmark, sometimes touching the 3/4's mark when revving high and some white smoke appears around the engine bay at times after driving car for long periods. It failed it biennial smog inspection but luckily I found a loophole to get my California Tags.
    I told myself I will not bring this car with me to college in this condition (only an hour drive away from home).

    Last week, my dad and I decided to tackle the job and I said F it, okay let's do it.


    I am here today to post a blog about this repair job and hopefully help others while I get some advice as well.

    Below are some pictures of the work done. And updates to what I have found.
    Last edited by salvuhdor; 09-09-2015, 07:24 PM.
    Tags: None
    #2
    Below is a heater hose that went bad and after some searching does not seem like the correct hose. If anyone can confirm that would be great - connect to the cylinder head then to the heater core I believe. It has white build up inside the hose.


    My coolant is dirty. Not milky- just a dirty brown, last replaced about 15k miles ago with the BMW coolant- the blue stuff.


    Despite taking off the head, I did not find a crack in the head gasket nor the cylinder head or block. Nothing was warped to the human eye at least. Taking no chances and already having pulled it apart- I've taking it to a good machine shop to have it pressure checked and still getting it resurfaced.

    Polishing up some parts while waiting for the cylinder head to finish its check up.



    In all, this car has 140,000 original miles. I have just completed a timing system overhaul with new thermostat, new water-pump and main hoses less than 20k miles ago. My radiator seems good with no rust. I have called the machine shop and they said my cylinder head was in good conditions. Can that heater hose that connects to the cylinder head be the sole problem of a leak that caused the overheat issue and the white smoke being the burnt coolant coming in contact with the hot engine? And the dirty coolant? I should of bled the system before starting to eliminate some factors - but even then would my emissions (to be clear, I do not care about emissions since I received my tags but I do not want to be driving the car in detrimental conditions) be in any way related to his overheating problem. This can't be all due to a faulty hose can it?
    Last edited by salvuhdor; 09-09-2015, 07:45 PM.

    Comment

      #3
      Headgasket kit w/ bolts
      hoses and clamps
      - All coming in the mail from pelicanparts tomorrow. I will have no choice but to replace any used or worn part then I will pick up my cylinder head tomorrow and reassemble everything.

      If problem persist I will look into the cataylic converter, I've heard that if my car carries a faulty one it would be backing up the exhaust system causing the overheating issue.

      Comment

        #4
        Do the mess under the intake if you haven't already
        sigpic

        (clicky on piccy to get to thread)

        Comment

          #5
          I will look into the cataylic converter, I've heard that if my car carries a faulty one it would be backing up the exhaust system causing the overheating issue.
          Personally, I'd start with a new radiator, as those tend to let the engine overheat if they
          get clogged up with brown stuff from the coolant.

          Much more so than the cat does.

          An expert on the internet,

          t
          now, sometimes I just mess with people. It's more entertaining that way. george graves

          Comment

            #6
            Originally posted by TobyB View Post
            Personally, I'd start with a new radiator, as those tend to let the engine overheat if they
            get clogged up with brown stuff from the coolant.


            t
            Thank you.
            Tomorrow I will assemble everything then bleed the system. I will use just distilled water until I find the source of the problem. I will look into getting a new radiator as well.

            Comment

              #7
              First a couple questions. Did you have any visible signs of a leak from anywhere in your engine that you could trace to a source? Did you do a compression test before you tore apart the head? It could of saved you a lot of time and money if you know it wasn't the head gasket but if you got the time and money to rebuild it that's pretty cool. And if it was just stuck at 3/4 it's possible your thermostat was just stuck half open maybe?

              Very possible your radiator is clogged up or dirty the way that coolant looks. If you could find a leak on either side of the engine that could narrow down the culprit, and while you have everything torn apart just do the basics that come in contact with coolant like profile gasket, water pump, thermostat, flush radiator and clean out the lines.

              Keep it updated, always curious as to what problems other M42 owners encounter.
              The fun never ends :-?

              89 318iS
              R.I.P 89 325i coupe
              89 335iC

              Comment

                #8
                Also if you have smoke and losing coolant that means air is getting in somewhere, so that could be a source of overheating but I'd think it would go higher than 3/4 with an air bubble in the system.

                Also what did you use to polish up your manifold? Looks wicked!
                The fun never ends :-?

                89 318iS
                R.I.P 89 325i coupe
                89 335iC

                Comment

                  #9
                  Originally posted by RCtheRed View Post
                  First a couple questions. Did you have any visible signs of a leak from anywhere in your engine that you could trace to a source? Did you do a compression test before you tore apart the head? It could of saved you a lot of time and money if you know it wasn't the head gasket but if you got the time and money to rebuild it that's pretty cool. And if it was just stuck at 3/4 it's possible your thermostat was just stuck half open maybe?

                  Very possible your radiator is clogged up or dirty the way that coolant looks. If you could find a leak on either side of the engine that could narrow down the culprit, and while you have everything torn apart just do the basics that come in contact with coolant like profile gasket, water pump, thermostat, flush radiator and clean out the lines.

                  Keep it updated, always curious as to what problems other M42 owners encounter.
                  The heater inlet hose has terrible wear and corrosion was visible - that was a visible sign. I did not do a compression check just a simple vacuum hose check with a tool my dad had from the 80's and said engine had vacuum leak.

                  Dang it, will keep that compression check in mind.

                  The gauge was not stuck but slowly would move to 3/4 mark and back down to mid mark when I revved it over 3k RPMs.

                  I am currently putting everything back together, the guy at the machine shop looked at my old head gasket and said it had some wear indicating that it was not completely 100% tight. I'm now believing that a blown head gasket would of been inevitable if I kept driving it like that.

                  Welp everything is up in the air, just want to crank this thing by tonight and get it running. I'm hoping coolant would stay clean, if not then definitely check the radiator.

                  As for the polishing, all I do is take a power drill and a wire brush and get in there, careful not to touch the openings. Intake manifold looks pretty sick now and will take photos of it after installs.
                  ----- Will give you update by tonight!--------

                  Comment

                    #10


                    This is the block.

                    Comment

                      #11


                      So what you see in the photo is that hose that I deleted and putting a straight hose from cylinder into The heater and also the coolant to that heater

                      Top pipe on car is coolant bottom pipe is air

                      Comment

                        #12
                        Advice I received from a m42 vet.

                        What you see above is a piece called - thermostatic bypass valve -. A coolant system recall piece installed on e30's around 1993-1995. This was done so that heater core would not burst and spray scalding hot water/air onto people in the cabin bay. This typically happens when you let your car overheat (people who don't take care of their cars get punished), too much coolant pressure and it burst. I read on how to delete it and add a lower PSI radiator cap.
                        If you remove this, the heater would blow very warm hot air when needed. But also sometimes blow hot air when air conditioning is off. Keep the recall piece installed and you will be safe from any rupture or incident from overheating.

                        Basically, My car was overheating. Assuming that this thermostatic bypass valve is functional and not the problem of my overheat issue, it prevented my heater core from the danger rupturing and spraying me with scalding coolant. If this was not installed I might of sued BMW for millions=)
                        I have decided to clean the part and put it back on. Since my car is overheating and I'm not sure this HG job will fix the issue.
                        Last edited by salvuhdor; 09-10-2015, 11:35 PM.

                        Comment

                          #13
                          Make sure that your fan clutch is good (if you still have it) and that your electric aux fan works. I've had problems with both at times.

                          Comment

                            #14
                            Just about starting it up needing the radiator and the air intake

                            Comment

                              #15
                              Car started! Some smoke around engine bay but all normal - for now at least.

                              I am thankful my car started but it still slightly overheats when revving and I continue to bleed the system. ( At this point I feel like diagnosing the the catalytic converter and losing the connection from headers to exhaust , it will be loud but then I would know if it's my stupid catalytic converter which I don't even need since I have my tags indefinitely)

                              I believe I did not strongly tighten the nuts that connect the headers to the rest of the exhaust.

                              If anyone here knows how to fix this problem may the bmw lords bless you- but while waiting for parts I installed a euro clock I had - 6 button obc and it short circuited because I had the wires out and naked and turned the car on - now my tachometer won't work but everything else does. My RPM and Speedometer are non functional as of now =(
                              -I checked the fuses and will recheck but none were broken.

                              Comment

                              Previous 1 2 template Next
                              Working...
                              X