Injector gaskets

[Kishada]

Anyone know which way round the small ones go?
These are the ones that are about 10mm in diameter and sit in the recess in the head, not the big copper compression washers.
These small metal compression gaskets have a few hills and valleys from centre to outer and really would have a correct side up.
I've made a best guess but wondered if anyone else has been here before.

Can't find anything in the FSM with regards to this.

Cheers

P.S. It will be interesting to see if this cures the slight whistle when on boost.
This small gasket on injector #1 was off centre and had been leaking causing quite a carbon build up around the end of the injector body in the seat and had deteriorated the threads a bit in the head itself.

 

[stinka]

You want the washer forming a funnel going away from the nozzle, if this makes sense

 

[stinka]

Also the small washers dont do any sealing this is done by the big copper ones

Whistling on boost is likely to be either intercooler split (very common) inlet manifold gasket or the throttle housing spindle has a seal

I've done all the above including totally removing the egr valve, throttle flap complete with spindle and filling the hole's left with chemical metal (after cleaning and sanding fully) and resealing the throttle body gasket

 

[Kishada]

6 minute reply.
In the words of the Bo Selecta Michael Jackson, "Faster than lightning, goddamn it's frightning!" :lol

Thanks a lot for that.
I think that's the way I have them in but will check for sure before I finish the rebuild on Saturday :thumb2

 

[stinka]

6 minute reply.
In the words of the Bo Selecta Michael Jackson, "Faster than lightning, goddamn it's frightning!" :lol

Thanks a lot for that.
I think that's the way I have them in but will check for sure before I finish the rebuild on Saturday :thumb2

Well, they compress if i remember correctly so its one chance to fit them, but i spose it wont hurt to pull one out

Btw your local diesel specialist will have an abundance of them as they are common on other vehicles

 

[Kishada]

I've been following your problems and cheers for the suggestions. It already made me check pretty much all of those after reading your posts.
Already had the 'cooler off a few times to check for oil deposits, replaced the throttle body to I/M rubber ring gasket as it was p*ss poor, inlet manifold is currently off to replace head gasket but no signs of failure and no EGR system to worry about fortunately!

Only reason I'm doing the H/G is due to pressure (bubbles) in the header tank when I shut the engine off. No overheating. Head passed the pressure test.

The small ring of carbon around the pintle on each injector matched the centre hole on these gaskets except injector #1, and upon inspection it was noticeably off centre....and actually trapped in the recess by a substantial build up of carbon on the walls of the bore. The other 3 just fell out!

One of the many interesting things I'd rather not have found when I tore the engine down! Thermostat housing gaskets that should never have been re-used, a turbo elbow nut that wasn't tightened down because the thread on the end of the nut was stripped....

 

[stinka]

Btw, I have a spare intercooler, urs for £40

I just need to get it pressure tested by my mate who will bung it up and drop it in a tank of water with an airline connected and 20 psi through it, it will be going on ebay after i get it tested anyhow

 

[Kishada]

Good price!

I'm flat broke with this headgasket just now but please do post up if you throw it on the 'bay.

 

[stinka]

I've been following your problems and cheers for the suggestions. It already made me check pretty much all of those after reading your posts.
Already had the 'cooler off a few times to check for oil deposits, replaced the throttle body to I/M rubber ring gasket as it was p*ss poor, inlet manifold is currently off to replace head gasket but no signs of failure and no EGR system to worry about fortunately!

Only reason I'm doing the H/G is due to pressure (bubbles) in the header tank when I shut the engine off. No overheating. Head passed the pressure test.

The small ring of carbon around the pintle on each injector matched the centre hole on these gaskets except injector #1, and upon inspection it was noticeably off centre....and actually trapped in the recess by a substantial build up of carbon on the walls of the bore. The other 3 just fell out!

One of the many interesting things I'd rather not have found when I tore the engine down! Thermostat housing gaskets that should never have been re-used, a turbo elbow nut that wasn't tightened down because the thread on the end of the nut was stripped....

Ah right I see :thumb2

You had head refaced then ? or you checked it with a straight edge/feeler gauges ?

I had a coolant loss on mine but was water pump seal, I ended up just resealing it with rtv as pump was sound

 

[Kishada]

Yup, head skimmed 5 thou and pressure tested.
Clear evidence that the water pump was done not long before I bought it and there was more K-Seal than coolant in the cooling system!
Although it drove absolutely fine and got me hundreds of miles home, I think the head might have cooked before the water pump was replaced.
Hopefully find out tomorrow when I get it all back together!

 

[stinka]

Sweet. You got a nice thick head gasket going in there then bud ?

 

[Kishada]

Just a standard blueprint number (gasket kit inc headgasket £78.28)
Nissan just for the record was £95+ vat just for the headgasket and a couple of weeks lead time!
The flaming skim and pressure test was £81 !

 

[stinka]

You need a thicker one tho if you've had the head skimmed on a diesel

My pug hdi van was ruined after I did the headgasket, seemed to lose about 20% of power and I'm sure it was down to the slight raise in compression after the head was skimmed, I used the thickest gasket i could get as advised. Turbo Diesels hate compression, mine was running 19psi pre head off and just seemed to hate boost after HG swap, i had to knock it right back to 12psi as it ran really poor at high boost.

Just my 2 cents

 

[(RIP) PLANK]

the classic turbo whistle is most commonly caused by the flexi bit on the exhaust :thumb2

 

[Kishada]

Cheers for the suggestion Plank, although flexi downpipe is nearly new.
Stinka, I just ran a conversion from thou to mm and it was a big surprise!
0.005" = 0.127mm
I was never worried about clearance issues but as you rightly stated, I might have a bit of a compression increase there...or a smaller engine since there's now less volume per cylinder...I read a really good article on this once, something like static vs dynamic compression...
I was going to get a thicker headgasket but ended up just winging it :augie

Initial impressions after rebuild are good.
A very important point to note here is that I ran the engine up to temp then shut it down and did the valve clearances before i even bothered to drive it.

They weren't just out, they were in the next county!

It now idles beautifully quiet and has epic torque from almost idle when pulling away.

Not given it a good blast yet. Going to make the 13mile commute to work tomorrow and then immediately drain the oil for an oil change and give it a good once over up on the 4 poster ramp to make sure everything is Ok.

Cheers

 

[stinka]

Cheers for the suggestion Plank, although flexi downpipe is nearly new.
Stinka, I just ran a conversion from thou to mm and it was a big surprise!
0.005" = 0.127mm
I was never worried about clearance issues but as you rightly stated, I might have a bit of a compression increase there...or a smaller engine since there's now less volume per cylinder...I read a really good article on this once, something like static vs dynamic compression...
I was going to get a thicker headgasket but ended up just winging it :augie

Initial impressions after rebuild are good.
A very important point to note here is that I ran the engine up to temp then shut it down and did the valve clearances before i even bothered to drive it.

They weren't just out, they were in the next county!

It now idles beautifully quiet and has epic torque from almost idle when pulling away.

Not given it a good blast yet. Going to make the 13mile commute to work tomorrow and then immediately drain the oil for an oil change and give it a good once over up on the 4 poster ramp to make sure everything is Ok.

Cheers

Sounds like you have it covered mate. Like you say 5 thou is nowt to worry about and at the end of the day these engines have been largely un changed since the 80's, whereas the pug hdi can be a bit fussy (albeit based on the ancient pug 1.9)

These engines are built for torque and if you have plenty of that ur laughing :thumb2

 

[Kishada]

Well, it seems I built a big....blue....kettle!
Idled fine for 20mins last night as I filled it up and bled it out.
The first time I put the engine under load and boosted the head today, the coolant hoses turned rock hard and the expansion tank turned in to a violent bubble bath.

Going to apply to record breakers. Had the head off in 2hrs tonight after work!
Clear evidence that cyl #4 has breached in to a coolant port.
Cyl's #2 and #3 have evidence of combustion gases breaching the coolant blanks on the gasket (the ones on the drivers side of the block).

Time to look at and measure the old gasket and see if I now need a 3 notch or even custom thicker gasket as it seems the block may well be less than straight....

 

[Kishada]

Can the mods please change the thread title to 'Headgasket Failure' and delete this post?

Cheers

 

[stinka]

Bloody hell mate, thats a pain in the arse :/

you had the head pressure tested and it passed, so maybe the block is cracked :nenau

 

[Kishada]

It was never that bad before the teardown. Only marginal pressure in the cooling system.

Possibilities include:

Warped block
Cracked block
Hydrolocked headbolts(s)
Stretched headbolts
Thinner gasket than original fitted

Ruled out:

The Original gasket was a zero (original) gasket (it measured at 1.25mm with some cheap digital verniers.
The one I fitted from the Blueprint kit was a 1 notch which should be 1.20mm (it measured 1.40mm)
The 3 notch i got today should be 1.30mm (it measured 1.40mm)
All the measurements with the digital calipers prove is that the gasket I fitted was thicker than the original which is a good thing.

The warped/cracked block is unlikely as it was never that bad before and a thicker gasket should have taken up an surface imperfections better than the thinner one on it.

The hydrolocked/stretched headbolts seem to be the most likely cause of failure. Got hold of a syringe so i'm going to make sure all the 18 holes are bone dry before assembly this time.
I didn't have access to a syringe or ideally an airline the first time 'round as I'd normally blow the holes out.
The bolts aren't classed as stretch bolts but this will be the third, possibly 4th time round that they've been torqued.

The one thing that surprises me is how low and close the first 2 torque setttings are before the final angular tightening stage!
I checked the torque after i did the bolts the first time 'round to get some idea of how tight they were and they were only about 150NM !