Northern Auto Tech - ECU and Blue & Me Repairs

Technical Engine block exhaust manifold stud snapped

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Technical Engine block exhaust manifold stud snapped

OMG, my fault! I didnt checked that its in daNm :) So thats another thing and it should be tightened realy solid - 18Nm + 30 deg . Thanx a lot for this info!
 
Rado77 said:
OMG, my fault! I didnt checked that its in daNm :) So thats another thing and it should be tightened realy solid - 18Nm + 30 deg . Thanx a lot for this info!
Click to expand...

18nm on my 480mm long torque wrench is a very light one finger push

With the wrench in the vice 18nm is the hardest pull I can manage using only my first finger (next to my thumb) at a distance of 14.5cm. At 14.cm it is impossible to click the wrench because my finger opens and the pain is too great to fight it. I believe at that distance my finger is experiencing the same force as picking up 13kg

M8 Bolts in the aluminium gearbox and differential are specified at 20nm.

Edit: I got confused. We were both wondering why your manifold nuts were becoming loose. It was the other guy who was breaking them off.
 
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Yops. So I definately need torque wrench. So this is my plan:
1, unscrew nuts
2, tight them to 20Nm in correct manner on cold engine (I think mechanics are doing this on cold too...and I think that studs in alu head are stronger on cold...)
3, tight 30 degrees
4, install contra-nuts
5, after few days - remove contra-nuts, re-tight with classic wrench, install contra-nuts back

OK?

PS: I think my manual ex man grinding (using flat surface with glued sandpaper 80) was good because after installing I had no leak, also checked on higher rpms on hot
 
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I feel perfect! :) Sometimes I turn off radio to hear that silence, that engine smoothness :) Now I'm waiting for next salary to buy 5L of cheap oil + Selenia K to make that engine flush. Two Valeo oil filters are waiting at home ;-)
 
Guys! Issue is back! Everytime when I try to fix that ex man, everything is working ok , but only few days. Theres small leak again. Its not noticable on idle (hot or cold).
I think everything is because engine was overheated. I tried to grind ex man to flatness , which is almost ok but I didnt thought about cylinder head deformation by heating. And because cylinder head is ALU, its deforming easier that ex man made from iron.
I think that once head and ex man changed it's shape by overheating, atomic structure changes too when it colds. And theres no way to fix it properly, because its still deforming by each heating wrong way. Picture shows current status - nothing interesting. In the left upper corner is bigger stud 10 with bigger nuts...its leaking somewhere around 2nd cylinder...
So my question - to buy two thickest gaskets. I know that its not proper way but maybe if there is much flexible material between head and ex man, it could help...?
 
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And picture. Plus other thoughts like Permatex Ultra Copper paste RTV, J-B Weld ultimate copper RTV silicone...
What is the best (and home made + cheapest) way guys?
 

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It's not generally advised to apply sealant upstream of the catalytic converter but I've been using this "stuff" for years now and have applied it to a couple of the older designs (where the cat is not a "maniverter". By which I mean it's not part of the manifold/down pipe like our Pandas). The reason they don't recommend it is that there are elements in the paste (I think mostly silicon?) which can poison the Cat. However I came across this Abro stuff on one of my many visits to the States and if you read the description it says it's suitable for use on catalyzed systems, says it on the tube too:

https://www.ebay.co.uk/itm/Abro-Exh...-Cement-Repair-Putty-Paste-170g-/401193014070

You've been able to buy it over here for some time now and it's my standard "go to" when assembling exhausts (I'm on my second tube). From what you are describing the gap you are trying to seal is obviously very small so doubling up on the gaskets might well be worth a try but if that doesn't work maybe I think I'd be tempted to try some of the Abro. Although my repairs seem so far to be successful - no more blowing and still passing the MOT emissions - It's up to you if you decide to use it. Please don't come back to cry on my shoulder if it does muck up the Cat!
 
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Thanx Jock. I have similar paste from Bosal. The problem is that after few hours it completely hardens. But I think I need something "flexible" because that gap is causing by shape change of ex man (or head) during heating.
So now are different options:
1, buy new whole maniverter (300 Eur) - but this doesnt solve problem if head is changing its shape wrongly
2, to make 100% flatness of head outputs & manivert - but again, it will still change its shape wrongly during heating
3, use double thickest gasket - this is my favourite option for now...
4, identify that gap on hot engine and use some thin piece of gasket only on concrete cylinder output (crazy solution, there could be many other leaks when its cold...)
5, buy new head - for me impossible, too expensive + a lot of work

This situation is complicated because of overheated engine...on normal engine I'll change gasket and thats it. But this is special situation :)
 
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I thought about it (of course) :) But 2 related things - as 1st, when I tightened ex man nuts, I tested engine, but I forgot to connect 1st lambda. Strange that no light appeared on dashboard! But I think this error will be still in memory, maybe noise is camshaft position related.... 2nd - I cleaned valve cover and sludge around camshaft, and maybe some **** passed to VVT valve or variator directly. So 1st I'll make diag + reset, re-learn. 2nd will be planned triple engine flush. And then I'll see if something changes. Engine is running still well, acceleration ok, starts are fast, so its only noisier = cosmetics. Temporary solved by radio volume :)
 
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Pugglt Auld Jock said:
It's not generally advised to apply sealant upstream of the catalytic converter but I've been using this "stuff" for years now and have applied it to a couple of the older designs (where the cat is not a "maniverter". By which I mean it's not part of the manifold/down pipe like our Pandas). The reason they don't recommend it is that there are elements in the paste (I think mostly silicon?) which can poison the Cat. However I came across this Abro stuff on one of my many visits to the States and if you read the description it says it's suitable for use on catalyzed systems, says it on the tube too:

https://www.ebay.co.uk/itm/Abro-Exhaust-System-Silencer-Pipe-Sealer-Cement-Repair-Putty-Paste-170g-/401193014070

You've been able to buy it over here for some time now and it's my standard "go to" when assembling exhausts (I'm on my second tube). From what you are describing the gap you are trying to seal is obviously very small so doubling up on the gaskets might well be worth a try but if that doesn't work maybe I think I'd be tempted to try some of the Abro. Although my repairs seem so far to be successful - no more blowing and still passing the MOT emissions - It's up to you if you decide to use it. Please don't come back to cry on my shoulder if it does muck up the Cat!
Click to expand...

Fairly sure oxygen sensors do not like silicone.
 
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How about separating (saw-cut) the flanges between cylinders 1-2 and 3-4 as it is already between 2-3 ? It might bring a little more "flexibility tp the manifold ...

BRs, Bernie
 
judderbar said:
Fairly sure oxygen sensors do not like silicone.
Click to expand...

Absolutely. Silicone will destroy them but that was the point of buying the Abro paste because it specifically says on the tube that it's suitable for use on catalyzed systems. From my, very limited, experience with it so far their claim would seem to be true.
 
judderbar said:
Fairly sure oxygen sensors do not like silicone.
Click to expand...

Absolutely. Silicone will destroy them but that was the point of buying the Abro paste because it specifically says on the tube that it's suitable for use on catalyzed systems. From my, very limited, experience with it so far their claim would seem to be true.
 
Interesting idea Bernie! If diag reset/re-learn and oil changes doesnt help (I think dont), then during spring I'll dismount it, buy joint gauges and absolute flat tool and measure properly gaps on head outputs and ex man. The problem is if I find gaps on head outputs because make it flat I have to remove all studs (pain)... I can make 100% flatness of ex man using this stripe of sand paper sticked on 100% flat surface (photo). Then I can cut ex man as you suggested between 1,2 and 3,4 , use thickest gasket and tight all nuts by specification
 

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