Alfa Romeo Owners Club of Australia Forum

Technical => 116 Series (Alfetta Sedan/GT/GTV & Giulietta Sedan) => Topic started by: Mat Francis on December 19, 2008, 09:35:28 PM

Title: Head Gasket
Post by: Mat Francis on December 19, 2008, 09:35:28 PM
For the second time in 3 months the ever reliable alfetta ( :-\) has decided to chuck a head gasket. So, tomorrow, head will be off and down the road to be machined. We measured it all up last time and it seemed fine, however i think a combination of not being 100% perfect and last weekends hiding around the island may have put it over the edge.

The question here is, in anyone else's infinite wisdom, is there anything else special i should perhaps be considering doing to try and stop it happening again? (and don't say, "don't thrash the car," because we all know that isn't going to happen). Or just any other input or advice would be muchly appreciated.

If not, feel free to read, have a laugh at my misery and move on with your life  :D
Title: Re: Head Gasket
Post by: graemericardo on December 19, 2008, 10:05:12 PM
hi matt
i have just done the head gasket on my car gave it a belting at pi and it is fine
i suggest you take it to vinny sharp at pace engineering complete with cams he did a great job with mine
regards graeme ricardo
Title: Re: Head Gasket
Post by: Ray Pignataro on December 19, 2008, 10:13:49 PM
Have the head checked for hardness pressure checkedand use coppercoat on the head gasket
Title: Re: Head Gasket
Post by: Mat Francis on December 19, 2008, 10:17:36 PM
Thanks Graeme, but i'll have one more crack at it myself before i place the burden on someone else, firstly because it's so close to christmas, and also because i could use the practice.

Between dad's decades of motor-mechanicing/aircraft engineering/spannering/building red hot renualts, and my youthful ignorance, hopefully, maybe, with a lot of luck and one extra motor engineer who has forgotten more in his life than i'm ever likely to know, we might get one to last more than 6 months!!!
Title: Re: Head Gasket
Post by: Mat Francis on December 19, 2008, 10:18:22 PM
and also thanks Ray- we now have the beginning of a real man's shopping list.
Title: Re: Head Gasket
Post by: pep105 on December 20, 2008, 01:49:06 AM
Matt
Do you have another head you can try? Seems strange your getting such a short life span from the headgasket. I know you track your car but still in my experience anyway these engines are quite robust and can take a decent thrashing. Maybe theres something freaky with this particular head?  Has it been machined or shaved a few times ?
Title: Re: Head Gasket
Post by: Mat Francis on December 20, 2008, 09:55:41 AM
unfortunately i couldn't tell you much about the engine pep- i know it was in a paddock basher for a few years, (probably had the living crap beaten out of it), then we got 2 whole cars for $250. when the previous 2L engine went, we replaced the head gasket and dropped it straight in. it ran beautifully for about 3 years, until three months ago when the head gasket went. so we replaced that and did the valve guide seals at the time. i guess i don't really have any right to complain, it's sure earnt it's keep.

so in short, i have no idea if anything has been done to it, but i would think it would be a fair assumption to say it hasn't had much done to it.
Title: Re: Head Gasket
Post by: vin sharp on December 20, 2008, 06:44:45 PM
Mat,
Make sure you use an O/E head gasket; (Reinz) as these are far superior to any other.
They will hold 12:1 compression on full race engines, so you shouldn't have any problem.
Make sure the liners are all level and have.001"-.002" protrusion above the block.
DON'T use Coppercoat on it!!!
Use anti-sieze compound on the threads and nut/washer face. Tension in steps 20,40,60ft/lbs. COLD Re-tension after first 45 minutes running, then back off one hex and re-tension at every oil change, or every other event.
DON"T forget to bleed all the air out or the cooling system and re-check level!!!
Usually good for 3,4,5 years of club racing!!
Cheers,
Vin
Title: Re: Head Gasket
Post by: Jekyll and Hyde on December 20, 2008, 07:02:44 PM
QuoteThe question here is, in anyone else's infinite wisdom, is there anything else special i should perhaps be considering doing to try and stop it happening again? (and don't say, "don't thrash the car," because we all know that isn't going to happen). Or just any other input or advice would be muchly appreciated.

Only one thing I'd add - have a look at the liners when you have the head off to see if one is split.  Its not common, but mine did it heading to winton in march this year.  Well, actually, it was going from Benalla to winton in the morning that seemed to kill it, was fine on the way to Benalla the night before!  I'd also done a head gasket on mine about 3 months earlier.
Title: Re: Head Gasket
Post by: Ray Pignataro on December 20, 2008, 08:15:21 PM
Vin why not use coppercoat? Have these gaskets already have a sealing compound?
Title: Re: Head Gasket
Post by: Mat Francis on December 20, 2008, 10:19:31 PM
Vin- priceless information. if beer's your thing i owe you a couple next club night.

Luckily the gasket we got the other day is in fact a Reinz, so we should be right there.

Machined the head today, had a bit of corrosion, so we ended up taking of .015 in. I am informed by taking off .020 the compression ratio will increase to approx. 10.5 to 1? if this is indeed the case, i would guess i would be looking at a ratio somewhere in the order of 10.2 ish to one now? 98 octane fuel and cold plugs here we come!
Title: Re: Head Gasket
Post by: vin sharp on December 21, 2008, 09:44:14 PM
Ray,
Yes these Reinz h/gaskets already have a surface compound on them and should be assembled onto a clean, dry surface.
Split liners are caused by mixture detonation which in turn is cause by too much igition advance/too much compression/ lean mixture/ too hot spark plugs or any combination of the above! Constant blown headgaskets are also a symptom of these conditions; a split liner being a big wake-up call!
Title: Re: Head Gasket
Post by: graemericardo on December 21, 2008, 10:08:02 PM
mat
listen to vinny
he has vast experiance in these matters and does a great job
thanks vin
graeme ricardo
Title: Re: Head Gasket
Post by: Mat Francis on December 22, 2008, 05:51:06 PM
Thanks again Vin and Graeme- and despite buying the copper coat i assure you after Vin's advice it will not be used.

I suspect that the gasket went because i stupidly forgot to change the plugs at PI. The set i had in were one hotter than standard, which obviously is not good for lots of revs constantly. Some things have to be learnt the hard way i suppose.
Title: Re: Head Gasket
Post by: alfagtv152 on December 22, 2008, 07:11:19 PM
Hi Matt,
Vin Sharp is the man I would ask for any tech answers,take it as gospel,and he has been a big help to me. The only other thing I would check is the depth of the hole that the locating dowls go into in the head just to make sure the head will sit all the way down.
Cheers
Andrew