Results 1 to 8 of 8

Thread: 300tdi head off - new rings?

  1. #1
    Join Date
    Jun 2018
    Location
    Melbourne
    Posts
    16
    Total Downloaded
    0

    300tdi head off - new rings?

    Hi all,
    Recently got myself a landrover (94 d1 300tdi manual) and have had a bit of a run of bad luck. Took a gamble on a no- history vehicle that looked clean enough, and is at least rust-free. So far have changed the serpentine belt tensioner and stud (stud snapped on the way home after purchase), water pump (noticed the bearing was gone when replacing the belt) the heater matrix and pipes (matrix started leaking on the way to vicroads to get it registered), and other logical things like fluids and hoses.

    Anyway, latest joy is I’m pretty sure I’ve done the head gasket. Was fitting a low coolant alarm to replace the radiator cap, bled it as I did when I did the water pump and heater matrix and thought all was good, but air would return to the top of the rad within 10 seconds or so as evidenced by the alarm.

    Was still driving it as it wasn’t getting hot whilst I wondered what could be causing the air, when one day the heater went cold and it started to get hot quick. Pulled over straight away and came back to it hours later - bled ok, hot heater, then after 10-15mins cold heater and hot engine again. Expansion tank was cool too, and too hose firmer than I remember.

    I’ve checked the 3 way bleed thing, new thermostat, so I’ve resigned myself to pulling the head and having a look unless you tell me I’ve missed something. Could that have been the cause of the radiator air too?

    What wanted to ask (finally) is what the verdict is on doing rings and big ends whilst the head is off? Haven’t had it long enough to get a good idea on current oil consumption but it does use some, and there is a bit of pressure evident with the oil filler cap off but I don’t really know what is considered excessive.

    I’ll post some pics of the bores when the head is off, but I’m just wondering whether rings and deglaze is worth doing, or do I just do the head and gasket, live with the engine for now, and start saving/build up a second engine and swap them over down the track. A full rebuild isn’t really on the cards just now, but I could see myself building one up in the next year or two to drop in.

    Thanks, the forum has been very helpful so far!

  2. #2
    Join Date
    Jun 2013
    Location
    Universe A
    Posts
    2,076
    Total Downloaded
    0
    If it's running ok and you have medium term plans to do another motor properly, I'd just do the head gasket if you work out that what it is for sure.

    The 300tdi motor is pretty tough and will still go ok even when pretty sick, so maybe not much to be gained in a "backyard quickie rebuild".

    Cheers
    James

  3. #3
    Join Date
    Apr 2016
    Location
    Melbourne
    Posts
    4,203
    Total Downloaded
    0
    What was your bleed sequence.
    This is kind of vital on a 300 tdi, and it's a specific bleeding method, a bit different to your average car.

    Without special tools involved, the two easiest ways to bleed are:

    1/. use a drink bottle of some type propped into the filler neck of the expansion tank, and fill er up till the drink bottle is half full or so... and bleed it off at the thermostat housing

    2/. unbolt the expansion tank and hoick it up higher with some prop type thing .. maybe 4-6 inches, if the hoses allow. Then bleed again as per above.

    if you notice the pattern here, the issue with bleeding is that the level of coolant at the expansion tank needs to be considerably higher than the motor(more specifically the bleeder nut on the thermostat housing).

    The 3rd way you can do it is to use a rad pressure testing type kit to produce pressure at the expansion tank, usually whilst it's still cold.
    This is now my preferred method(having got a pressure kit).

    method 1/ was provided by member blcknight here, and I buggered that up first time and started overheating on first test drive. Pulled up and (had tools) did again at a servo .. and having purchased a drink I didn't really need, got it right for the test drive home.
    Then I moved to method 2/ which lost a lot less coolant than method one, and better result were had when D1 was parked nose higher(so to speak).. such as jacked up at front, or rears parked at the low point of a driveway.

    Then having got the pressure testing kit for my D2 .. it had the cap adapter for the D1, so pressure bleeding works first time, every time.

    Also note you said you noticed it wasn't getting hot. If you based this observation via the dash temp gauge .. you need to re think the notion. I think the dash gauge doesn't show it's getting hot until a bit over the 110°C mark of the coolant temp!
    So the likelyhood was that it probably DID get hot .. it just didn't indicate this in a more accurate manner for your consideration.

    My personal opinion on the 300 tdi is that a coolant temp gauge is more important as an accessory than a low coolant alarm. Mine has a very very very slow leak in the rad core, and loses about 1 lt of coolant per couple of months. Being such a long time and being pretty much lazy, I sometimes forget to remember the reminder I set myself the night before to check and top up... so I 'regularly' drive with the coolant a low level in the expansion tank ... never heats up(runs regularly in the low 80's to high 70's).
    The other gauge of importance is an EGT(if you are going to attempt a tweak on the injector pump to get a little bit of power from the underpowered donk), and then I find the oil temp gauge is handy on very hot days.

    My point in this reply is really to highlight that you may not have bled the system 'properly' .. before concluding that the HG has popped.

    Oh! .... and welcome to the North Coburg 300Tdi owners club!
    Arthur.

    '99 D1 300Tdi Auto
    '03 D2 Td5 Auto

  4. #4
    Join Date
    Jun 2018
    Location
    Melbourne
    Posts
    16
    Total Downloaded
    0
    Thanks for the advice/suggestions

    Ak83 thanks for the CoNo welcome, I’ll keep an eye out. I’m pretty sure it was bled properly- I’ve read all the posts, watched all the videos, and the heater and all hoses were hot.

    Ironically, I was fitting the coolant level alarm *and* an engine guard temperature alarm as this whole thing unfolded. So I didn’t have an external gauge for the initial event, but have subsequently.

    The symptoms match exactly a number of anecdotes for a head gasket failure, so I’m confident enough to pull the head and take a look…

    And thanks James for the encouragement to put it back together without messing with the pistons, I think that’s the way I’ll go as long as the bores look ok. Didn’t particularly like the idea of working upside down with oil on my face…

    Will let you know how I get on…

  5. #5
    Join Date
    Jun 2010
    Location
    Buderim
    Posts
    255
    Total Downloaded
    0
    Arthur - Regarding pressure bleeding - can you explain exactly the process that you use please. It is easy enough to put a schrader valve into an old cap - are you filling with the overflow bottle elevated - then pressuring whilst bleeding?
    For the original poster - the following image gives you some idea of the internal water levels relative to the temperature sender.
    Attached Images Attached Images
    1998 D1 in showroom condition, 1999 D2 TD5 with everything, 2000 P38 showroom condition.
    Freelander 2 2012
    1992 RRC sold and now pranged.

  6. #6
    Join Date
    Apr 2016
    Location
    Melbourne
    Posts
    4,203
    Total Downloaded
    0
    Quote Originally Posted by peter51 View Post
    Arthur - Regarding pressure bleeding - can you explain exactly the process that you use please. It is easy enough to put a schrader valve into an old cap - are you filling with the overflow bottle elevated - then pressuring whilst bleeding?
    ....
    I guess an old cap with a schrader valve would do the same thing.

    I got a rad/rad cap pressure testing kit. and in essence the same thing .. cap with an air connection.
    If you make a cap/valve up, just make sure it holds pressure too. Use a hand pump, and having the pressure gauge is handy somewhere along the line to see how well it holds pressure too.

    IIRC, pressure relief is 15PSI, and I usually pump it to 20PSI, and tap hoses and stuff. Expansion tank not elevated, but filled to the brim. Filled right up to the limit, the level is closer to the level of the top of the thermostat housing.

    Thinking about it(the schrader valve) tho .. I'd reckon any other type of air fitting would be more ideal, in that you connect up any air pressurising device(even a compressor with regulated air into it) ... making the connection a bit more positive, and in a way a bit more controllable when time to release the pressure too.
    As an example of this: when I was trying to get my V8 D2 going, it had overheating issue(why the pressure testing kit was bought). pressurised the cooling system to spot leaks, and leaving it overnight pressurised was handy diagnosis whilst cold. Also wanted to check for any issues when pressurised and hot.. and to remove the pressure whilst hot at 90-ish degrees, it was easy to control the steam safely.
    So if you ever found yourself wanting to check for hot coolant conditions, I don't know of an easy way to release pressure from a schrader valve without getting into the flow of the hot steam(or water).
    Arthur.

    '99 D1 300Tdi Auto
    '03 D2 Td5 Auto

  7. #7
    Join Date
    Jun 2018
    Location
    Melbourne
    Posts
    16
    Total Downloaded
    0
    So the gasket was definitely gone between 2 and 3:

    blowngasket.jpg


    Current dilemma is that the head gasket supplied (Victor Reinz MLS) has an odd restriction and I don't know if it's acceptable. The holes for the oil gallery in the front-right corner of the engine are misaligned. Supplier says the whole batch (and other thicknesses of gasket) are similar, and photos and videos online seem to show some degree of misalignment in this location, so maybe it's deliberate to raise pressure?

    Does anyone have any experience with the 300tdi MLS gasket and could tell me if its ok or not? See bottom-left of image below, just next to the rivet

    gasket.jpg
    Cheers,
    Rohan

  8. #8
    Join Date
    Jun 2018
    Location
    Melbourne
    Posts
    16
    Total Downloaded
    0
    Never mind, seems they’re all like that…

    Notes and observations on 300Tdi heads, gaskets and stretch bolts - YouTube

    Will button it all back up on the weekend with a new head

Tags for this Thread

Bookmarks

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
  •  
Search AULRO.com ONLY!
Search All the Web!