Melted Piston.

Dan Sarandrea (Phila) said:
Regarding the TTY bolts that are presently available (the FIAT OEM 17MM TTY bolts that came on late 10-bolt and all 14-bolt head engines are NLA), with a stock FI head in order to get enough reach into the block while using hardened washers, the contact pads for each head bolt had to be milled down, IIRC about 4mm.

http://xwebforums.com/forum/index.php?threads/25857/
Click to expand...

Hi Dan

The TTY bolts from C.Obert are longer than stock (longer than the standard bolts from MWB anyway) by at least 1/4". I was concerned that they would bottom out, but that is clearly not the case given my measurements. Using the hardened washers that came with my motor, the TTY bolts matched the stock (long and short) bolt length.
 
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Ulix said:
Wait a minute.
Are you putting the engine back together with a squish height of 0.6 mm?
As Clint said: "do you feel lucky?"
Click to expand...

I did the math calculations AFTER I put it all back together :( . I assumed the popup is correct (couldn't recall the actual measurement from the Mahles), based on the CH of 34.15mm. The pop up has to be closer to the designed .025". I wish I had checked this more carefully, however I don't see how that could be a .010" deviation with the same CH.

The Wiseco's have a chamfer at the top of the piston, that did not clear the deck * TDC - I'll have to call Wiseco & see if they can give me that dimension, just for clarification. ( I didn't factor the volume of the chamfer into the volume equation either, so that will actually lower the compression slightly also).

X19_0284.png


I need to re calculate the numbers based on the .025" pop up.
 
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All Good (whew!).

Pop up is approx .026"

wrapped some soldering wire with a little blob of putty (with vaseline)

uncrushed was 1.56mm

X19_0115f.jpg


inserted in bore * 30º BTDC & rolled over TDC

X19_0115h.jpg


1.06mm
X19_0115e.jpg


checked against my calipers

X19_0115a.jpg



Now I need to recompute the CR :)
 
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Looking forward to seeing your calculations

I'm starting to worry that my static CR may be too high even though I'm trying to compensate for altitude.
 
Using Steve's Formula - bolded values are my revised numbers.

Volume at BDC is (swept volume - pop up volume)+ flycut and ring land clearance volume + gasket volume + chamber volume.

Volume at TDC is (volume in gasket - pop up volume) + flycut and ring land clearance volume + chamber volume.

Volume of BDC over Volume at TDC is expressed as a ratio to one (xx:1)

Your bore is 87.00
Your Pistons are 86.15 above the top ring land and the top ring groove is 8mm down from the crown.
Your Valve Flycut measured volume is 2.1cc
Your Piston sits at 0.65mm plus deck
Your Combustion Chamber measured volume is 36cc
Your head gasket is going to be 1.5mm compressed and has an inside fire ring diameter of 87.2mm (assuming a Felpro 21195-PT2)

So lets do some math...

Swept Volume of the cylinder.
Pi x R squared x Stroke
3.14285 x (43.5 x 43.5) x 67.4
3.14285 x 1892.25 x 67.4
400.831cc

Volume of the piston 'pop up'
3.14285 x (43.075 x 43.075) x 0.65
3.14285 x 1855.4556 x 0.65
3.790cc

Volume of the head gasket.
3.14285 x (43.6 x 43.6) x 1.50
3.14285 x 1900.96 x 1.50
8.961cc

Volume of the ring land clearance.
[3.14285 x (43.5 x 43.5) x 8] - [3.14285 x (43.075 x 43.075) x 8]
[3.14285 x 1892.25 x 8] - [3.14285 x 1855.4556 x8]
47.576cc - 46.651cc
.925cc

and then put these numbers into the equation,

Volume at BDC = (400.831 - 3.790) + 2.1 + 0.925 + 8.961 + 36 = 445.027

Volume at TDC = (8.961 - 3.790) + 2.1 + 0.925 + 36
= 43.271

Static Compression: V at BDC / V at TDC (445.027 / 43.271) =

10.285:1

note: there is a chamfer at the top of the piston that is not accounted for - actual compression will actually be less. Not sure how much less. Need to see if I can get the specs on that from Wiseco, I never measured the depth of the chamfer and the diameter of the crown inside the chamfer...
 
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Got it running last night. Cranked it for a while with the plugs out / EMS disconnected to get some oil pressure build up first.

Welded the boss on the oil pan for the CPS, to make sure the air gap cannot alter.

X19_LH24_00001zb.jpg






 
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Setting up left & right tailpipes - had to add 'dogleg' to clear the wells in the back 1/4's

X19_0198.jpg


X19_0154.jpg


X19_0154a.jpg


muffler now clears crossmember & rear valance with plenty of space - previously I had irritating rubs from the muffler/rear valance & left tailpipe / well . Added rigid liner flex section to reduce any stress on the header.

X19_0154c.jpg


Exhaust work finished
X19_0207.jpg
 
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Thought I was going to loose the X last night. Car died on me (wideband gauge indicated full rich condition) on two separate occasions a block from my house (I realized afterward it was brought on by heavy acceleration). First time, by the time I had made an adaptor to check the fuel pressure pre & post regulator, the condition cleared itself & engine started & ran fine (of course).The second time I disconnected the fuel / ign systems, removed the plugs & cranked the motor to clear the cylinders & saw fuel spray out #2 cylinder - which started a nice little fire in the bay :shock:. I ran about like a chicken with it's head cut off looking for my fire extinguisher & then used the garden hose to put it out. I then found the extinguisher right near the garage door where I had placed it earlier :eyepop:.

Fortunately it looked much worse than the reality - it melted the injector harness & a couple of vacuum lines. Beyond that, just a large amount of soot. I cut out the injector loom & replaced it.

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#2 injector was sticking open & dumping fuel. For whatever reason, the injector only stuck when I accelerated hard, up until yesterday I had still only been driving with under 5K rpm & 3/4 throttle for break in of the new rings. I had bought a set of six injectors (0280155832, 24lb) for the LH2.4 conversion, so I had two spares.

After fixing the wiring, replacing the injector & cleaning it all up I took it for a hard romp up over the neighborhood mountain roads going to redline to make sure there was no issues. Hopefully the bore didn't suffer any damage from fuel washing, I don't think it ran rich long enough to do that. No sign of oil smoke or fuel contamination of the engine oil.
 
Could I please have an order of extreme excitement please?

Man that was close and could have gone way wrong. I have gotten distinctly paranoid about fuel fires with my Fiats, the carb ones have a nasty habit of having the fuel inlet pull out if the carb body.

Jeff had his 924 partly burn up as well last weekend. Lots of expensive damage on that one due to most anything not steel or aluminum burning up

Glad you saved it and the damage was minor.
 
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Ouch. Is Jeff's car salvageable?

When the flames shot up, the bay looked much like a BBQ grille gone awry - honestly, my first thought was push it into the road & walk away - I didn't think I was going to have time to subdue it. Fortunately for me it was more of a fine mist in the air rather than large volume of fuel.
 
Made it 282 miles on this head gasket.

Massive clouds of coolant smoke on the way home from work today. Made it off the parkway into a local street. Coolant dripping out the taipipes.

Got it towed home. I'll pull the head tomorrow. Pretty sure I'm gonna see deformed fire rings again. Have not had any discernable knock since dropping the compression closer to 10.2 vs. the 10.7 I had previously.

Need to locate a felpro HG. Vic's recommended I go that route vs. using another standard gasket. They are out of stock. Anyone know of a source for the Felpro version?
 
head gasket

Navalineasport has the non integrated stainless steel ring type head gasket which is what I used on my 11:1 engine with no problems thus far with over 3,000 miles on the engine. I did initially suffer detonation due to other issues which distorted the stainless steel rings and I had to do a complete gasket replacement. It is a costly bugger initially but the rings can be re used and the composite gasket can be bought for around 40.00. They come in several thickness and bore diameters. Not cheap as you can imagine.
 
Sorry for your trouble Hussein...

MWB lists several but not the maker... from 15 bucks to over 100.

http://www.midwest-bayless.com/csea...playMode=Grid&Condition=-1&Search=head gasket

I did look at Vicks and see about 4 kinds there... was not able to find any at Allison's and O'berts as well. You could give them a call.

The Fel-pro site responds with this:

http://www.felpro-only.com/performance-head-gaskets/

And when I enter engine specifics it gives me this...

http://www.fme-cat.com/Engine.aspx?...asoline; Naturally Aspirated; 138BS&action=bk

I can only find "MLS" designations and no part numbers and lastly, no "HG" designation.

Unless you abbreviated Head Gasket as HG when you typed... (duh?)

If so, then it would appear to be an "MLS" designation and I wish you luck. I'm pooped!
 
Thanks for the input, guys.

fiatfactory said:
Not sure if Felpro make a 14 bolt version?

Fiat make a non retorque Astadur version.

SteveC
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Hi Steve

I actually messaged you via eBay - your felpro listing says contact you for the 14 bolt version...

Do you have stock of the Fiat non retorque version? Trying to figure out an expedient source for a better/different version than what I've been using.

Obert lists a range of gaskets with original PN's, don't know until I can talk to him if his are OEM TTY appropriate. He was not available yesterday, so I'll call later today to figure that out. I bought the TTY bolts from him last time, and will need a new set anyway.

Others have indicated that the aftermarket replacements shouldn't matter in terms of TTY or not, however I would like to rule that out by using a gasket that is known to be acceptable for use with TTY, since this is now HG #3 failure since building the motor. If it fails again after this, I'm unsure what I will do. I'll have to cross that bridge if or when that happens. Hopefully it won't.

Going to take the opportunity to modify the heater return port to extend the branch with steel, to remove the heater hose proximity to the header runner. My current hose is very crispy & the outer layer has cracked. I noticed it yesterday lunchtime when doing a cursory lookover of the bay. I put a couple tie wraps on it to hold it until I got home, it's only about 12-14miles. When the coolant cloud appeared, my first thought was that the hose had ruptured.
 
lookforjoe said:
Others have indicated that the aftermarket replacements shouldn't matter in terms of TTY or not, however I would like to rule that out by using a gasket that is known to be acceptable for use with TTY, since this is now HG #3 failure since building the motor...
Click to expand...

I think that says it all... 3 failures.

There certainly is a difference in head gaskets... polymer composite construction gaskets (i.e. what Fiat and Goetze call ASTADUR) are designed to be used with TTY style bolts... regular composite gaskets are not designed to be one torque only with TTY bolts, the head gasket will compress and settle with heat cycles and the bolts will then effectively lose clamping force, leading to failures.

If you want to go with TTY bolts and the TTY method then you need to use a polymer composite gasket... otherwise use the TTY bolts but go thru the regular torquing and retorquing method with a regular composite gasket.

I'm all out of Astadur H/gaskets for 14 bolt... but I'll see if I can find a few more and let you know.

SteveC
 
lookforjoe said:
Need to locate a felpro HG. Vic's recommended I go that route vs. using another standard gasket. They are out of stock. Anyone know of a source for the Felpro version?
Click to expand...


I've had good results with victor reinz gaskets. I think you mentioned that you have used them in your Volvo? I have a spare 14 bolt one here if you want it. Just need to pay shipping from Germany.

Cheers,
Dom.




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