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Think I just blew a 300tdi head gasket . . .

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300tdi gas tdi
13K views 26 replies 10 participants last post by  east high 
#1 ·
Have read almost all the threads on this topic I could find on here, and am grateful to you all for the wealth of knowledge on here.

Questions Up Front:

1) any quick and dirty tests for this (other than what I've done below, which seems to confirm exhaust in the coolant circuit)

2) anyone have a consolidated parts list? I saw that RenChing recommended new valve seals at the same time as gasket replacement, and am wondering if anyone's got a one-stop list of part numbers and recommended suppliers. I am pretty sure)I need a gasket; should I order new bolts as well as valve seals? My gasket's a two-hole model, for whatever that's worth.

3) thoughts on what to look for in a machine shop to check the head? Will anywhere that checks heads be able to check and, if necessary, skim this? Or will they be like, "what engine did you say that was from????"

Background:

Engine was rebuilt (Urban Land Cruisers/Rovers, or whoever they use for their rebuilds) before installation--only about 15k miles ago. Having read RenChing's account of his gasket failure, it occurs to me that mine's been "chuffing" at highway speeds/under heavy use since I got it in. So maybe this has been a problem for some time. . .

but today, after only about five miles, my Madman EMS started freaking out--low coolant (sender is at t-stat housing plug), and then, shortly after that, engine temp.

Turned her off immediately and got towed home. Filled and bled coolant system, started engine with reservoir cap off--instant geyser, followed by mild turbulence and some vapor escaping that didn't smell particularly like exhaust at idle. Put my hand over filler hole to see if there was excess pressure--initially, nothing, then sudden increase in pressure and a huge geyser. This was all done with a cold (well, 95 degrees like it is outside today) engine.

In retrospect, I remember noticing some unusual and oddly pale smoke going up past the back window when in 5th gear at maybe 50mph on a hill and under heavy peda right before the madman started going nutsl, so I think that means coolant in combustion chambers, although at the time I just thought, "huh, I didn't notice that before--I should increase pre-load on the boost spring in the fuel pump . . ."

No coolant obvious in oil, nor oil in coolant at this point.

Radiator was replaced last week by a marginally qualified mechanic (old one blew up so far from home it was cheaper to have it hauled to a rover-oriented place than home) and they did a crap job of bleeding the system, which I discovered when I showed up to pick the truck up and immediately rectified in the parking lot, getting at least 1.25 liters of air out of the system at the t-stat housing. . . . possibly connected to this failure, or maybe just correlated. . .

Sorry I seem to be completely incapable of writing short, pithy posts.
 
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#2 ·
Good write up, short pithy posts rarely receive a response. Sounds like a blown head gasket to me that was months in the making and accelerated by an incompetent cooling system bleed. At least the work to remove the head is not too difficult, but find a qualified shop even if that means shipping it out of state.
 
#3 ·
Sounds like it. There is a rental kit at most autozone that will tell you definitely with chemical analysis.

Some notes:

Head gasket is surprisingly easy. Get a top end gasket set and a new two hole composite gasket. You can reuse the bolts if they aren't too stretched or haven't been reused 5 times previously. If in doubt new bolts too.

Remove head and take it to a machine shop to have the bottom and exhaust/intake side resurfaced., then replace the stem seals with the head off. Clean block thoroughly and measure for any warp with a straight edge.

Replace the head, change the oil, top off the coolant. Done
 
#5 ·
Thanks all. Any advice on what to look for in a machine shop? And can head-skimming be done with valves in place? I guess I'm going to pull them to do the seals anyway, so maybe that's a dumb thing to ask . . .

Lastly, with bolts of unknown age/number of uses (RAVE says they can be used up to five times), should I just order all-new bolts? I think total cost will be about $20 from LRD, so maybe this, too, is a stupid question. . .
 
#11 ·
can head-skimming be done with valves in place? I guess I'm going to pull them to do the seals anyway, so maybe that's a dumb thing to ask . . .
Let the machinist do the head and you can ask him the "dumb questions", but no real question is dumb for those with the insatiable quest for knowledge.
Here's your checklist:
Order a complete head set
Order the correct gasket (google 1, 2, 3 hole head gasket, 300TDI).
Order 8 new valve guides and 4 exhaust valves
Order new head bolts
Order 8 new valve cap spacers
Order a thermostat, P-gasket, water pump, and coolant hoses if any of yours are suspect and if you have to ask how do I tell if they are suspect, just order all new coolant hoses.

When the head is ready after being rebuilt update the thread for someone local to install it.
 
#6 ·
Check my post for the bolts. No you cannot skim with the head assembled, at least no reputable shop will.

Number all the parts as they have come out to re assemble, frankly with all the work involved you just just do an entire hear reconditioning. Only the valves/seats to cut and the guides to check
 
#9 ·
Thanks, all--some interesting arguments re. a new head. I'll call the machine shop tomorrow and see what they think I'd be into it for with a skim, new valve seals and guides, and valve/seat cutting . . . I reckon if that's $300 or so, a new head might be a good option. Especially a britpart one for 277 UKP at LRD! (seriously, I'd get a Turner one)

Thoughts on type of straight edge to use for checking head/block surfaces? Steel ruler from somewhere? Thinking I should pull the head and make sure the block is OK before ordering anything at this point. . .

Thanks!
Bill
 
#12 · (Edited)
If you purchase a top end gasket set it will come with the valve guide seals, p gasket, valve cover gasket, head gasket, and manifold gasket. I'd suggest Elring brand as the only one to buy.

Cant speak to NC but my cost to have a head shaved and valve job done is $140, bump that up to retail and its still probably less than $200.

The replacement heads that are available are aftermarket made by a company in Spain named AMC. Turner uses AMC heads. There are companies gas flowing the amc head and that makes a noticeable difference.

https://www.best-of-land.com/en/sho...00tdi-performance?vh=discovery-i-300-tdi-1995


Joel is in Clayton and has a car trailer etc. He knows 300's backwards, forwards, and sideways. That's who I'd reach out to if you want someone else to open her up.
 
#14 ·
Thanks much, gents. Very much appreciate the advice. Planning to do the work myself, as I've done everything myself thus far (failed district pump oring, new p gasket, new ps pump nightmare, etc.) and don't plan to stop now. Is there an LR part number for that top end gasket kit so I can snag it on lrdirect?
At this point planning to open it up and check for head and block warpage--if just the head is not straight I'll check with the machinist for a ballpark cost.
I've got half a mind to go with a new head if it's off at all, since this head has more than likely been skimmed /gone through at least once (rebuilt just 15k miles ago) and another refurb may be throwing good money after bad...



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#16 ·
It doesn't look bad it just looks dirty. Get a pair of jumper cables clamp the negative to the body and the positive to the tip where the nut is and see if it heats up. Anyway a bad plug doesn't directly signify a bad head.

Land Rover repair manual has the maximum shave for the head which you can measure very easily with a caliper.

Top end set is stc2802 it does not come with hg
 
#18 ·
So, yeah, looks like it's been going for some time--major gasket erosion by cylinders 2 and 3. Not entirely sure the block face is level--obviously haven't cleaned it up yet but was able to fit a .003" feeler gauge under ithe machinist's straight edge at several points --what's acceptable?



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#20 · (Edited)
I'm not sure land rover gives a specific for block warpage. The commonly used figure is below . 004in for an inline 4.

I would clean up the block with a 3m bristle disc (not a conditioning pad) then use a large wooden block wrapped in Emory paper to flatten it out. This is most definitely the shade tree method, but it works without pulling the motor apart. Most will just wiz wheel the block, wipe it clean and call it a day.

I've seen way way worse than what you have posted there


Edit: the score down your cylinder is more concerning to me. Maybe it could be honed?
 
#21 ·
There is no way to measure block warpage when the surface has not been scraped and cleaned to remove old gasket material, scale, and carbon. Measuring at this juncture is the proverbial fart in the wind.
 
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#22 ·
KGH, thanks for the link--have the RAVE and electronic troubleshooting manuals, but didn't know that one was out there.

What of the warning in the overhaul manual re. refacing the head? Manual says on p. 20 that if the head is warped beyond spec (.08mm) to replace, not reface. . . seems from the comments thus far that getting these skimmed is common practice.

Napalm, thanks for the ideas--will grab a wheel thingmo tomorrow. That scoring looks more pronounced in that photo than I think it is--I just checked it with my fingernail and can just barely tell it's there by feel--and it took me a while to even find that. Cause for concern? Time for a bottom-end job too? Ugh.
 
#23 ·
Update thanks for all the help. Cleaned everything up, determined cylinder not scored, head and. Lock both well within spec via machinist's straightedge and feeler gauges, ordered new top end gasket kit, head gasket, and head bolts. Got the head on Friday, finished with ancillaries in Saturday (holy cow was there a lot of coolant at the bottom of the oil pan!--shot clean past my drip pan), and fired her up Saturday afternoon.
Absolutely running better than it ever has--no longer sounds like it's going to fall apart at 3000 rpm (when accelerating--I don't cruise there...).
Thanks again for the advice and encouragement.




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#24 ·
Good news all around.
Keep us posted on the reliability...
Now that the head gasket is good, you'll need to fix something else in the future.
Happy motoring and Live large behind the wheel!
 
#26 ·
Just an update—6000 miles and running like a scalded dog. Other car has been dead so this has been the wife’s daily driver and we’re racking up miles.
Drove it 1200 miles to Michigan and back recently and did 75-80 the whole way (1.2 transfer case), with the exception of the giant hills on 77 in W VA, on which we never dropped below 60. And we got 20 mpg. It’s like a new truck.


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