Fiat 850 Sedan Journey
- Thread starter Perl
- Start date
Perl
Modify Everything
Thanks FiatRn that helped a lot. I got everything that I thought would fix this head gasket issue but after a new Cometic MLS gasket, new Elring head bolts, Head alignment pins, a new Snap-On torque wrench and torqueing the head to 38 ft lbs I filled the radiator with fluid and the coolant is dripping out of the seam between the head and block in multiple places. It leaks out of the back above the fly wheel and it leaks out of the side under the headers. I didn’t even start the engine. This engine is cursed. I checked the torque on the bolts and all were fine. I’m not sure what to do next. I guess it’s pull it apart and go back to the machine shop to deck the block.
fiatfactory
Steve Cecchele
MLS gasket was never going to seal on the stock block surface finish, it's simply too rough... a rougher Ra is preferable when using a composite gasket as it holds the gasket in place and the composite material will deform/compress and fill in the uneven surfaces finish.
MLS gasket requires a very fine Ra (surface finish measurement) on BOTH the head and the block faces, or it just won't seal.
SteveC
MLS gasket requires a very fine Ra (surface finish measurement) on BOTH the head and the block faces, or it just won't seal.
SteveC
Dr.Jeff
True Classic
Extremely frustrating after all of your work! This is beginning to sound like a SOHC engine with it's inherent HG failures. 
Check the length of the new dowels with the depth of the holes/recesses they go into (on both the head and the block), to make sure they aren't holding the held from seating all the way down. Also check the lengths of the new bolts with the depths of their holes to make sure they aren't bottoming out before allowing proper tension.
As we discussed previously, the finish on the sealing surfaces (head and block) will need to meet the requirements of whatever type of gasket is being used. However I would not expect that to be the cause of this particular leak - while filling a cold engine with coolant without even starting it. This sounds more like a fundamental issue with the general mating of the two surfaces; either one (or both) is not true, or the dowels/bolts are interfering, or something similar.
Check the length of the new dowels with the depth of the holes/recesses they go into (on both the head and the block), to make sure they aren't holding the held from seating all the way down. Also check the lengths of the new bolts with the depths of their holes to make sure they aren't bottoming out before allowing proper tension.
As we discussed previously, the finish on the sealing surfaces (head and block) will need to meet the requirements of whatever type of gasket is being used. However I would not expect that to be the cause of this particular leak - while filling a cold engine with coolant without even starting it. This sounds more like a fundamental issue with the general mating of the two surfaces; either one (or both) is not true, or the dowels/bolts are interfering, or something similar.
Perl
Modify Everything
Thanks SteveC and Dr Jeff for the input. I was told that about the block surface with MLS gaskets but gave it a try anyway. I didn’t think the failure would be that significant. I decided to once again take the top end apart, clean things up and use a new stock head gasket. Again this is not the fault of the head gaskets it is my fault. I have learned a lot doing this so it is frustrating to fail but firsthand experience and knowledge is a good thing. I like to add at least one picture with my posts but nothing would look different than my previous posts.
I made the change, changed the oil and radiator fluid and started the engine. It starts right up which I really like and I ran it for about 5 minutes to get some heat in it. I drained the oil and it wasn’t tan and milky but it was not see thru. I put in new oil and ran it for about 10 to 15 minutes completely up to temperature that stayed at 180 at 2000 RPM then drained the oil. The oil didn’t look much different than the first batch. Not tan and milky but not clear. Not sure what the means. When I take the dip stick out while the engine is running there is a lot of smoke that come out of the dip stick hole but none comes out of the valve cover filler tube. I really don’t know where I am with this engine. Next I think I will change the oil again, top everything off, put everything together and drive it for a little bit. I really want to try the taller transmission gears and the GPS speedometer.
I made the change, changed the oil and radiator fluid and started the engine. It starts right up which I really like and I ran it for about 5 minutes to get some heat in it. I drained the oil and it wasn’t tan and milky but it was not see thru. I put in new oil and ran it for about 10 to 15 minutes completely up to temperature that stayed at 180 at 2000 RPM then drained the oil. The oil didn’t look much different than the first batch. Not tan and milky but not clear. Not sure what the means. When I take the dip stick out while the engine is running there is a lot of smoke that come out of the dip stick hole but none comes out of the valve cover filler tube. I really don’t know where I am with this engine. Next I think I will change the oil again, top everything off, put everything together and drive it for a little bit. I really want to try the taller transmission gears and the GPS speedometer.
Dr.Jeff
True Classic
If everything was rebuilt then it likely needs some break-in to seat the rings, etc. That may be what you are seeing at the dipstick.
Along @kmead's idea about head-gasket leaks showing in the coolant, there are inexpensive test kits to detect gasses in the coolant.
Hopefully things have been resolved.
Along @kmead's idea about head-gasket leaks showing in the coolant, there are inexpensive test kits to detect gasses in the coolant.
Hopefully things have been resolved.
Perl
Modify Everything
Thanks all for your continuing support of this project. All ideas are welcome. It’s funny thru all of this I have drained the coolant multiple times and have never seen evidence of oil in the coolant system also I have never since evidence of coolant in the cylinders. The engine runs strong and blows no smoke at all. Is it possible the block is cracked so the coolant runs into the crankcase but nowhere else. I just don’t know. I am going to run the car on the road for a little bit and see what happens. Dr. Jeff I ran the engine initially at 2000 RPM with zinc additive for almost 20 minutes to break the engine in which is when I found the first issue with the head gasket. I don't know if that broke the rings in. This oil change I will add zinc back in and see how it goes.
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fiatrn
Jonathan is the FiatRN
To est the integrity of your cooling system, you could pressurize the coolant system and see if the level changes over an hour or so of sitting pressurized. Or just watch the coolant level carefully as you drive - if you are losing coolant and can't find an external leak...
Perl
Modify Everything
Well good news for once. I filled it with oil and zinc additive and started it and it started right up like usual and then let it come up to temperature and all seems good. There is very little smoke out of the dip stick hole and it sat and idled at 900 RPM at 200 degrees. When I revved it up a little the temperature would go down. When the car is hot and idling the oil pressure is between 10 and 20 lbs and it shoots up to about 50 lbs when revved up. I didn’t say in the last post but the alternator was not charging and I found I had a wire in the wrong place. So the charging is working great too so all looks good. Now to get it out of the back yard to road test it.