Replace head gasket, compression test

LOL... so I double checked...

that's actually the 1.65 Astadur for the TEN bolt M10 engine (up t0 10/85)...so I was pretty close..

14 bolt M10 1.65 Astadur is 7580221 (11/85 on)...which supersedes to 7637103



SteveC
 
After installation, what is the procedure to drive the car until retorque and how to drive afterwards? When is the gasket completely settled?
 
First torque on assembly. multiple stages, the more the better so the head clamps down evenly, 15/30/45/60 and then finally 69 lb/ft. This is going thru all the bolts /nut one at a time in torque sequence to each value, then stepping up the wrench to the next value, and repeating... it takes a little while, but certainly pays dividends by only having to do the head overhaul / gasket replacement once.

First re-torque after one heat cycle... run car, fan cycles on / off maybe three times, shut her down. Let it completely cool, overnight is best, retorque in the morning when the ambient temp is coolest.

Second re-torque, I usually do after maybe 100 miles (160km) so in your case this would be after maybe ten heat cycles... again completely stone cold.

For retorques...In torque sequence, one bolt/nut at a time, loosen the bolt/nut around 1/4 to 1/2 a turn with a breaker bar, retighten back the same amount... I use a paint marker on the bolt nut to get it back to pretty close to its original position... Then swap the breaker bar for the torque wrench and using steady slow and even pressure on the torque wrench, take it straight up to the final torque value (9.5kg/m)

Make sure bolt holes and threads are clean. Oil and drain bolt threads. apply a small dab of antisieze compound under the nut/bolt head between it and the thick flat washer, this reduces the friction involved to a minimum and helps achieve the maximum clamping force without taking the fastener into the 'plastic (deformation stage) and keeping things in the 'elastic' range where the fastener will return to it's original dimensions when load is released.

follow these steps and you will have success.

added thought... it also pays to check the manifold to head stud/nuts at the re-torque stages... and also the exhaut flange nuts (if your running a twin front pipe) as these will also come down another 1/8 of a turn usually. after 100 miles I usually check the cambox bolt tension too, and run a feeler gauge thru the gaps to confirm the lash hasn't altered beyond spec.

SteveC
 
Wow. Thanks Steve. That means for retorque to remove injection house and inlet manifold. Lots of work. Luckily i bought a special tool to reach the bolts
 
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fiatfactory said:
Hussein,

it's not the bolts only, if you use the TTY method you ALSO need to use a compatible head gasket, the TTY system will not work just relying on bolts.

It need to be a polymer construction style gasket... off the top of my head Fiat 5951682 is the part number for M10 14 bolt style (but would need to check the number)

SteveC
Click to expand...

Interesting. Since the composition/construction of the gaskets I've bought from MWB is the same as the Victor Reinz gaskets I used to use on the white block Volvo motors, which use TTY bolts, I just assumed the replacement gaskets were suitable for TTY bolts as a matter of course. If one were buying Fiat branded gaskets there would actually be non-superseded gaskets for early style?
 
Hussein,

The Original TTY gaskets used by Fiat are called 'Astadur' and when you see one un-used they are really hard and firm, not like a 'regular' composite gasket at all.

The supersession of the Fiat number I think was a supplier change, Payen / Tako were an OEM supplier, and then all the replacement gaskets started to be Goetze (which is what is shown in the picture)

the 5951682 is definitely a Payen / Tako manufactured gasket,which I used a lot of back in the '90's doing top overhauls on fairly late 1985 to 1989 sohc fiats...

I remember the number easily as the Astadur head gasket for the twin cams that I favour for performance builds is 5951675, and on the twin cam I always retorque it anyway and use regular bolts, the Astadur gasket is very tough and good for high compression engines.

I recall reading somewhere in Fiat literature that the polymer construction gasket hardens and swells when heat cycled initially, so TTY bolts will stay tight... regular composite gaskets tend to compress when heat cycled, and then the TTY bolts loosen off.

Mxgrds,

I think you might be able to get away with just removing the upper portion of the injection manifold, and leaving the fuel rail and lower section in place... I've never done an injection car with 19mm head bolts before and have a specific 17mm head special Fiat tool that clears the injection manifolding, but still only gets about a 1/4 turn at a time.

SteveC
 
Head is on again. Did all the things as described by Steve. Not started yet though. I am waiting for in-outlet gasket for injection. Appeared i had the carburetted fitted. Learning moment. Big difference when torqueing. Went very smooth now as opposed to the previous one with the old bolts and nuts.


Question though: how to get the timing about correct without starting and using a stroboscope lamp? Don't want to start with the ignition way to early and blow my gasket again.
 
leakage problem

if you have the manual pump in service, pull it and check for a rupture in the diaphragm. or the check valve inside the pump. notoriously known to fail.
mikemo
 
Just a few "sense" more...

As suggested by the "Steves"... cleanliness is next to Godliness.

Make sure you also LUBE the bolts by dipping them in engine oil and letting the "drain" after chasing the threads in the block and thoroughly cleaning and blowing them out. Use caution and cover other pistons and holes.

Have the head PROFESSIONALLY checked to make sure its TRUE and if not, check to see if its been "milled" before and are you now going to mill it for true-ness or compression gain?

LASTLY... after milling or when installing new bolts, make SURE they are not "bottoming-out"... leaving the gasket and head itself improperly torqued.

HTH.
 
Mxgrds said:
Head is on again. Did all the things as described by Steve. Not started yet though. I am waiting for in-outlet gasket for injection. Appeared i had the carburetted fitted. Learning moment. Big difference when torqueing. Went very smooth now as opposed to the previous one with the old bolts and nuts.


Question though: how to get the timing about correct without starting and using a stroboscope lamp? Don't want to start with the ignition way to early and blow my gasket again.
Click to expand...

This write up is awesome for setting static timing;
http://xwebforums.com/wiki/index.php?title=StaticTiming
 
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Inlet manifold cooling

Still open? Not enymore.

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With EFI manifolding the coolant port does nothing, so to make it easy on yourself for future manifold removals, sure go ahead and block them off.

That way there's no need to drop the coolant level in the system to prevent the intake / exhaust ports from filling with fluid if the manifolds need to come off.

Mxgrds said:
Big difference when torqueing. Went very smooth now as opposed to the previous one with the old bolts and nuts.
Click to expand...

Sounds like you have the head bolted down much tighter this time, looking good for a positive result.

SteveC
 
Replace the head gaskets and retourqued as suggested. I have to say that the engine does not get so heated up that the fan hits in. Not when driving and not running idle. Cooling works fine. The temp meter is between 70 and 90 degreees when running. It very rarely goes above 90 degrees.

For retorque I borrowed a tool from my local garage to be sure that the torque applied is correct (I don't have a very expensive one). It did some additional turn on the bolts. An extra 45 degrees. Drove some 200 km's and retorqued again. This time no significant extra turn.

Drove some more, but still experiencing some air in the rad. Not much. How long will there come air out of the engine which got there when draining the coolant? The car runs great.
 
I've had some air bleed even 100miles after HG replacement.

I would also double check all hose clamps at the T/stat housing, branch pipe, expansion tank, etc., if there is any seepage at all, air will still be drawn into the cooling system.
 
Still exhaustgas in coolant

Bought a co test. Yep, still exhaust gasses in the coolant. Pulled the head again and found out that the same cylinder on more or less the same spot.

Blacktooth suggested To check if the bolts don't bottom out. Unluckily after I placed the head. But I checked by removing one bolt. Bolt hole is 5 mm deeper than needed. Good, or not?

Now the head was off, i tried to place the bolts and see how deep they go. It appears that the bolt will not go all the way. The screw-thread stops earlier. After measuring up I come to the conclusion that the bolts are 1 or 2 mm to long. Therefor a part of the torque is lost and the head is not pressed hard enough on the block. I noticed that the imprint of the gasket on the head was less or even not there on the bolt side. Bummer.

Post picture later.
 
'dere ya go... One very old "lesson" stored in a very old...

man to be the answer to a problem so many years later.

HA!

Glad I could help!
 
Mxgrds said:
After measuring up I come to the conclusion that the bolts are 1 or 2 mm too long
Click to expand...

Do you know how long your bolts are?

There is supposed to be a fairly thick hardened steel washer under each bolt, and if that is missing or replaced with a thinner or softer washer you could have this problem.

And if you haven't already, check for crud in the bottom of the bolt holes.
 
I don't have the exact length, but I do have the 5 mm thick washer. No crud. Placed the bolt manual, measured the length between block and bottom of top. Substracted the thickness of the head. Leaves 5 to 6 mm. With the washer in place, the bolt is just a bit to long. It doesn't bottom out, but the screawing thread stops to early.

I will put one or teo extra washers on top of the thick one.
 
Be sure to use the right type of washers. The ones used by Fiat are hardened so any additional ones should be as well.
 
Mxgrds said:
I
I will put one or teo extra washers on top of the thick one.
Click to expand...

That's a good solution, although as kmead says you have to be sure that the washers are hardened. There's a noticeable amount of crush in the head gasket, so you'll need several millimeters to spare

What is the history of these bolts? If they're new and too long out of the box then the washer is the right fix. If they're being used there is some possibility that they have stretched, in which case they have to be replaced - if you reuse them they'll stretch more and let the head gasket go again.
 
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