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Discussion Starter #1 (Edited)
My series 1 1750 has a boosted 2 litre Alfetta (Alpine Turbo) with 8.1:1 CR and running 0.8bar boost. Before I get crucified for messing with a series 1 1750, just know that I bought it this way almost 3 years ago and it has been a project ever since….My most recent problem is that it popped its head gasket (between No 2 and 3 cylinder). The car never overheated – it just started misfiring and I did the usual (spark and fuel) checks and determined the head was pad-op. Also, before I took the head off I started it from cold and it purred like a cat for about five minutes and then started missing again - each time either No 2 or No 3 cylinder was the culprit.

Decided to take the head off carefully in order to try to identify where the problem lay -

Firstly, I did notice that the head bolts did not appear to have the same torque when I removed it - the way I checked was to set my torque wrench to at 80, then 70 then 60 Nm and each time turn the head bolt tighter to hear 'the click'. Engine was cold – doing this 'test' some head bolts did not click at 60 Nm (WTF!). So first assumption is that original torqueing was suspect (it been running like this for a while). I never assembled my motor but I will be refitting the head myself for sure!

Looking at the head gasket (Victor Reinz) there are no kinks or obvious signs of detonation. I am attaching photos (hope they download properly). So gasket fine but head definitely lifted – so either head not torqued properly (therefore uneven pressure on gasket) or V Reinz never designed gasket for high cylinder pressures. I would have expected that if I had a detonation event or a pressure event and the gasket blew that the gasket would show some signs of this.

My liners are cooper ringed and there were no signs that it blew on the cooper ring side – if you look carefully you can see the cooper ring indentations in the (liner side) gasket fire rings – so, toit on the liner side – does that mean I need to do a receiver groove on the head as well. I am deliberately not running serious boost (for all the known reasons) so this would be overkill surely.

So, last test as to the gasket fault is to have the head checked for trueness and pressure tested. Using a flat metal engineering rule it did look like the head was not so flat anymore (by a ball hair) but the engineers will confirm trueness and pressure check outcomes.

So my first question is

• Assuming all is in order with the head – still true and no cracks, do I just refit the head (torqued properly this time) with another VReinz gasket, or

• Do I go for a different gasket –

o MLS - I cannot find an MLS gasket for the Nord (Nava Linea Sport makes a gasket with separate INOX stainless steel fire rings that according to the US Alfisti is the 'final answer' to all boosted Nord head problems. Problem is I do not speak Italian, they do not answer their emails – so they are permanently on lunch – the P-I-G-S economics acronym seems to be appropriate here
o Copper – an interesting proposition – has been used for years by the hard-core drag racers, and has all the right properties but its known problems are not sealing oil and water jacket well – so you'll have fantastic cylinder sealing but you block/head join will ****** and mix fluids like an incontinent. Which is why MLS headgaskets become such a rage. An additional problem with the Nord's is that the liners protrude ever so slightly above the deck. To my mind this makes the likelihood of a fluid leak/mix problem worse. There is a local manufacturer, Redline Headgaskets that actually produces and impressive looking copper Nord Alfa head gasket - Alfa 2L - Redline Gaskets. Do the engineers in the house think a solid copper gasket (with proper raised sections around oil, water and liners – like the redline gasket) is a problem for other reasons? Has anybody ever tried this and found it to work?

Please help
 

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Juniorgtar, I've also had head gaskets fail between 2 and 3. Maybe centre bolts take the most strain over the years and stretch most?
 

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Discussion Starter #3
Juniorgtar, I've also had head gaskets fail between 2 and 3. Maybe centre bolts take the most strain over the years and stretch most?
Yes, me too over the years and I think that may have to do with that area having less support for clamping load than number 1 and number 4 cylinder both of which have block support front and back (in addition to the liners) whereas right in the centre you have only the liners and support on the sides of the block. The liners have definitely not collapsed as I replaced all the liner O rings and the liners are flush on a rulers test.
 

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Long shot, when head bolts don't torque properly, as mentioned earlier check for stretched bolt. While head is off it's easy to check if head bolts are properly secured and fixed into the block. yes I've had the bolt pulling out from inside the block and will eventually strip out completely.
 

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We use Spesso head gaskets on all the turbo 75s here . No issues . They were also designed for these cars . Google Spesso . Some 75s run up 400 hp with these . It's also an 1800 .
 

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Discussion Starter #6
Long shot, when head bolts don't torque properly, as mentioned earlier check for stretched bolt. While head is off it's easy to check if head bolts are properly secured and fixed into the block. yes I've had the bolt pulling out from inside the block and will eventually strip out completely.
Thanks Joss, head bolts are fine and secure. I too have felt loose head bolts in the past which can be a problem. It would be very difficult to check whether my bolts have stretched though - no fin enough measurement instruments available. Belts and braces would be to change the head bolts completely but this is motor out, heat and general PITA. Thanks for that suggestion though.
 

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Discussion Starter #7
We use Spesso head gaskets on all the turbo 75s here . No issues . They were also designed for these cars . Google Spesso . Some 75s run up 400 hp with these . It's also an 1800 .
Thanks Kevin - the clever bit about the 75s is that Alfa turbid the 1800s not the two litre that offered 2 distinct advantages because they have thicker liners walls - 1. Less prone to cracking - people have jacked boost to insane levels as a consequence and 2. More surface area for clamp load around firing rings so better sealing opportunity than 2 litre. The local (Nord) racers have not had good experiences with Spesso which has been around for a bit. Almost everyone swears by VReinz but with a very clinical approach to block preparation, gasket fitment and prepping studs, bolts and washers for accurate torquing. Of course no-one has longish tried and tested experience locally with boosted Nords and so one is just not sure that VReinz can cope. If one looks at the 'dynamic' CR with boost then even with 8.1:1 static CR you are getting up to 12-13ish: 1 CR. This is what the racers are running NA and more with a VR so in theory VReinz should be up to the job with boost lower than 1 bar. But then there is the odd detonation...:thinking:..thanks for your comments
 

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This is probably a shade tree mechanic suggestion but would adding washers help with torquing the nuts? I wonder what the Australians use in their boosted cars.
 

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Junior how did you get the compression to 8.1:1, lowered the piston?
It seems you have rings in the sleeves to replace Cooper rings. Cooper rings normally have 2 or 3 sharp ribs, to cut into the cylinderhead, meaning the ring is the pressure seal. The gasket only keep the liquids in around it. I used them and don't like it, too much damage to the head, 2nd assembly wouldn't cut into old groves. You could use a ring that has a 0.2mm blund rib to press on the gasket's fire ring, similar to piano wiring.
The normal Spesso gaskets are good, one version have a loose fire ring, good but again it is very fidly to assemble. Then you can have Cooper rings made to fit inside the normal gasket. Speak to Kevin at Allan Y Brink in Pretoria.
 

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I would suggest that the engineers tell you if that ball hair that the head is out, is enough to cause the head to pass water. What would have been interesting to see on the gasket would have been the head mating surface on the gasket, as well as on the head as this would tell you if you were losing pressure between the head and the gasket instead of between the gasket and the liners.

Did you have oil in the water?
Water in the oil?
Exhaust gasses in the coolant reservoir?

On my guess it would seem that the head wasn't torqued enough, which lead to it's slight warping and subsequent failure of the gasket seal.
 

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Discussion Starter #12
Junior how did you get the compression to 8.1:1, lowered the piston?
It seems you have rings in the sleeves to replace Cooper rings. Cooper rings normally have 2 or 3 sharp ribs, to cut into the cylinderhead, meaning the ring is the pressure seal. The gasket only keep the liquids in around it. I used them and don't like it, too much damage to the head, 2nd assembly wouldn't cut into old groves. You could use a ring that has a 0.2mm blund rib to press on the gasket's fire ring, similar to piano wiring.
The normal Spesso gaskets are good, one version have a loose fire ring, good but again it is very fidly to assemble. Then you can have Cooper rings made to fit inside the normal gasket. Speak to Kevin at Allan Y Brink in Pretoria.
The sleeves are actually O-ringed. I used the term Cooper ring loosely, sorry! 1mm stainless steel wire in 0,8mm deep groove the made an impression on the sleeve facing gasket fire rings (see photo) so they definitely worked but they will not work if the head lifts/warps. I do not have a receiver groove in the head - do not want to muck about with ali - head. The stainless steel o-ring should work with a copper H/gasket (this is one of ways in which the copper H/gaskets are used. I just intuitively do not think the copper will work with the wet sleeves protruding (ever so slightly) above the Alfa blocks' deck height. The fact that no-one I know has ever used one makes me nervous. I'll give Kevin a ring and get his views, thank you. Cannot seem to source the separate fire ring Spesso - people only have the regular Spesso and as I said they do not say good things about this regular Spesso. If I am not mistaken Spesso made the original separate fire ring gasket for the old 2.5 busso's and people claimed they had trouble with these that were resolved with a one piece gasket - may have been that the problem was the way people fitted them. Dunno? Pistons are JE's (designed for some squish though head is hemi) gave them my head C/ch volume and they designed Pistons accordingly. Definitely worked - 141wkw and 298Nm on 0,8 boost - just shy of double the factory output. I am happy car is very tractable. Now to just stop things breaking....:devious:
 

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Discussion Starter #13
I would suggest that the engineers tell you if that ball hair that the head is out, is enough to cause the head to pass water. What would have been interesting to see on the gasket would have been the head mating surface on the gasket, as well as on the head as this would tell you if you were losing pressure between the head and the gasket instead of between the gasket and the liners.

Did you have oil in the water?
Water in the oil?
Exhaust gasses in the coolant reservoir?

On my guess it would seem that the head wasn't torqued enough, which lead to it's slight warping and subsequent failure of the gasket seal.
Definitely having the engineers tell me what's up with the head (is it true or not). If the head is still true I am going to crap myself because then I still do not know why the coolant leak and, what caused it. You can see the head facing side of the gasket in one of the photos. Nothing obvious wrong there and the same with the head itself. The fire ring/s where a gasket blow occurs tend to have a carboned burn mark when the the HG gives way. Nothing here which is a little frustrating. I have only seen pics of fire rings on boosted motors that have been damaged by detonation and the damage is very apparent. Definitely some water in the oil but only very little because I picked up the problem in my garage (literally) and never drove it further - the misfire would not go away and I did not want to drive it lik that. Mind you it idled perfectly the next morning until warm and then started missing again. Also fair steam in the exhaust that did not look kosher and a just trace of white smudge in the cap and cap getting brown - game over. My guess is also a torquing problem on the head - I hope... One thing I did not mention I did a compression test when the motor was cold and all cylinders compression was even at on average 6,5 bar. Then when it idled and started missing the next morning I immediately did a compression test and No 3 was 5 bar and the other were around 6.7/6.8 - this is a rebuilt motor.
 

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can your engineering works measure the head bolts with a micrometer and check it against spec?

also important to run a tap through the block side holes to make sure that the threads are clean so the torque applied translates to the correct bolt tension instead of being used up by friction.
 

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Discussion Starter #17
can your engineering works measure the head bolts with a micrometer and check it against spec?

also important to run a tap through the block side holes to make sure that the threads are clean so the torque applied translates to the correct bolt tension instead of being used up by friction.
Only if I can get a friendly engineer to visit me at home as the block is still in and I do not have the instruments to measure stretch and I do not know what the correct length is anyway and the bottom of the block would be a little uneven and one cannot get to it with sleeves in place and and and.......

The block has studs that protrude through the head. I will indeed tap the threads just to make sure of even torquing and no 'grit friction' - just not sure if I have a big enough tap!
 

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The sleeves are actually O-ringed.
This is called "piano-wiring" by the turbo freaks.

Cooper rings is a ring that go 5mm into the inside of the sleeve, and protrude the 1.6mm (thickness of a std gasket) above the sleeve. On top of this is the sharp ribs that cut into the c/head.

Resurface the head, taking as little as possible off. Fit a new gasket(Victor Reinz) with the pianowiring. Torque the head in the correct sequence and use gasket sealer(not std) on the outside of the block to stop water oil mix, as the piano wire may stop the head from bedding properly. Redo the torqueing after 1000km slacking the bolts one at a time in sequence and retorque it, before slacking the next. Redo this every 20000km after this. (Standard practice on a NA Nord engine at about 40000km) Accept that a gasket on a hard working turbo engine will last 60000km.

With 8:1 compression you can run 1 bar boost.
 

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I love this post.

I was taught that when retorquing the engine the first time, (I used to do this every 20000km on my 159i) to slacken the nut completely, add a drop of oil to the thread inside the nut, then torque. I was shocked the first few times when I saw some coolant under the nut once it was slackened but soon realized that the coolant was coming from the studs holes. The oil actually remains on the threads and you can feel even 80000km later that the nuts still are lubed by the oil. The oil is there to prevent the coolant from getting between the threads of the stud and the bolt, which causes rust and makes torqueing inaccurate.

Looking at those pistons: Just imagine if the valves were as large as those reliefs! :devious:
 
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