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Discussion Starter · #1 ·
well the ol' wasp started running like crapa llof a sudden. then a big puff of smoke then i hear a major exhaust leak. "crap!!" so i check the compression and i get 60 lbs in #1, 120 in #2 and #3, and 140 in #4. great that doesnt sound good. so i rip in ti the engine and i find a severly blown headgasket. now I've seen blown headgaskets befor, but not like this in an Opel. so what thw hell caused it and how the hell do i prevent it fron happening again?
 

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4ZUA787
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did u punch those two extra holes in ur headgasket to cool down the two and 3 exhaust ports??? that may have weekend the gasket and casued failuar or just a bad gasket. how old was the gasket?
 

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No doubt about that gasket causing the engine to run poorly. So the question is what caused the gasket to blow, or has it been in the engine long enough that it failed through attrition. It does appear to have been a while getting in that condition though. I would be checking for flatness of the head and block, especially in that area.
 

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Looks like either: (1) your head wasn't torqued evenly, (2) it warped from a extreme heat event or (3) the bolts started to loosen up. In the old days, I would change a valve cover gasket once a year, or sooner if needed, and check the torque on the head-bolts. I use to run a slightly radical 68 Mustang at the weekend night time street races and found it was a needed funtion.
Just my 2c's
 

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Flatness and proper torque

opelwasp said:
well the ol' wasp started running like crapa llof a sudden. then a big puff of smoke then i hear a major exhaust leak. "crap!!" so i check the compression and i get 60 lbs in #1, 120 in #2 and #3, and 140 in #4. great that doesnt sound good. so i rip in ti the engine and i find a severly blown headgasket. now I've seen blown headgaskets befor, but not like this in an Opel. so what thw hell caused it and how the hell do i prevent it fron happening again?
As has already been said, MOST likely cause is improperly torqued head bolt perhaps in combination of an extreme heat event somewhere in it's past life or perhaps even several times. Definitely need to make sure that both the block and head mating surfaces are absolutely flat after a suspected heat event and failed head gasket. When satisfied, punch the extra two coolant holes in the head gasket and prep with Permatex Copperspray.

Spray both sides one coat and let dry completely. Spray both sides another coat, let it set up and get tacky, place tacky gasket on block surface (don't forget coolant O-ring at right side timing cover) and immediately put head in place and torque in three steps (36, 54, 72). Increase torque wrench setting by a couple of lb/ft and make one more torque sequence circuit to be sure all are torqued evenly.

I didn't invent this method, but know that many knowledgeable racers use it. It works! :)
 

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Spray both sides one coat and let dry completely. Spray both sides another coat, let it set up and get tacky, place tacky gasket on block surface (don't forget coolant O-ring at right side timing cover) and immediately put head in place and torque in three steps (36, 54, 72). Increase torque wrench setting by a couple of lb/ft and make one more torque sequence circuit to be sure all are torqued evenly
Otto, thanks for that bit of info. Getting ready to put new head gasket on mine (along with every other gasket on God's green earth :rolleyes: ) and any preventative is appreciated.
 

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4ZUA787
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ive been told those two extra holes can lead to even more of a heat build up do to the water not circulating the way it was made to circulate and it will start pulsating in the back of the block and then not get back to the radiator to cool down, jus a tid bit of info i heard, also told by a long time mechanic that its not good to modify head gaskets.
 

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I've been adding those two holes to head gaskets for 14 years. Street cars and racing cars. It works...
 

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It Works!

Regarding the two extra water holes - "IT WORKS" - 'Nuff said Rally Bob ........

It appears that the steel sealing ring in the #1 cylinder of that gasket has been subjected to some vey hot gases. Perhaps the gasket was damaged or nicked there before ( or during ) assembly. There is also the possiblity that the head bolt on that corner has either bottomed out in the thread ( likely if the block has been decked ) or the thread itself has "gone soggy" and partially stripped out of the block. The edge of the gasket may have hung over the edge of the bore, even.

Was there any detionation "rattle" from the motor before the drop off in power?

Once combustion gasses find a weak spot - for any reason - they will carve their way through most materials.

Several things to check before you button up and use that block again ... the flatness of the head and block faces, the fit of the new gasket around the bores, the state of the threads in the block etc.. etc.
 

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Just out of curiosity is that a stock motor? Are there any modifications like bore sizing and such that could have played a role? Just for my own curiosity I'd like to know the make of the gasket too.
 

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I'm curious what the head looks like myself.....

It's rare for an Opel head gasket to have a 'blowtorch' type gasket blowout unless there's something inherently wrong....usually it's because an extreme lean condition or too much spark advance..
 

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Discussion Starter · #12 ·
ok, some answers. the engine has never overheated. there was no rattle before destruction. i always use copperspray, works great. block has not been decked. about 7 years ago i had it rebuilt by a local shop. pistons are 30 over head was rebuilt last summer with 2.0 valves and hardend seats. is has been rinning at 26 deg advance at idle Dennis at OGTS tested it in May. how it stayed running your gues is as good as mine. have an air/fuel meter on it and it always seemed to run rich as hell. had 150 mains, 175 air correctors F66 Emul. switched to 140 main, still rich. then 130 main 200 air correct and it showed a good mix at speed but super lean at idle. then 2 days after changing to the 130 mains POW! and here i am. here are pics.
 

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Old Opeler
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Not Pretty!

It looks as if the gasket has not been sealing around at least #1 cylinder - was there any blue smoke coming out the exhaust? #1 looks oily and super rich - it all looks fuel "wetted" . Was the carb subject to flooding or have a fuel inlet valve that does not seal?

The progressive leaning out of the mains may have the key to the head gasket damage in #1 cylinder. There has been a chronic fuel mixture problem by the look of it and the rings as well as valve guides need checking out to see if there are oil control problems too.
 

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Just a thought as I noticed the same things as Jim did. It also shows alot of corrosion in the area that normally has that little rubber piece for the head gasket. maybe you were getting a slight water injection on #1 until you leaned it out and got it hot enough to do that. Just an idea
 

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Which carb and what's size of "idle" jets?

opelwasp said:
ok, some answers. the engine has never overheated. there was no rattle before destruction. i always use copperspray, works great. block has not been decked. about 7 years ago i had it rebuilt by a local shop. pistons are 30 over head was rebuilt last summer with 2.0 valves and hardend seats. is has been rinning at 26 deg advance at idle Dennis at OGTS tested it in May. how it stayed running your gues is as good as mine. have an air/fuel meter on it and it always seemed to run rich as hell. had 150 mains, 175 air correctors F66 Emul. switched to 140 main, still rich. then 130 main 200 air correct and it showed a good mix at speed but super lean at idle. then 2 days after changing to the 130 mains POW! and here i am. here are pics.
You're not using an ICO solenoid in a 32/36, are you? :confused: In any case, your idle/transistion mixture is controlled by a separate "idle" jet. You appear to be OK as far as your "power" mixture is concerned, so I think you need to look at your idle/transition mixture. MTCW

ONE other thing, make certain that you don't have ANY depression whatsoever in the area of head gasket failure on the head and the block! :mad:
 

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nobody said:
Just a thought as I noticed the same things as Jim did. It also shows alot of corrosion in the area that normally has that little rubber piece for the head gasket. maybe you were getting a slight water injection on #1 until you leaned it out and got it hot enough to do that. Just an idea
I agree with nobody and Jim esp the part about "a slight water injection on #1" I had the same problem on a 4cyl Diesel Tractor 2 years ago. Blew 2 head gaskets before I had the head milled. JM2CW Jarrell
 

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Discussion Starter · #17 ·
i am using a 38 dgas. thes is no unusual wear or damage to the head or block surfaces. i may have had a loose head bolt there, but they all were torqued down real good when i pulled the head off. since i have the head off i am going to port it since it wasn't done when the 2.0 valves were put in.
 

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Unclamped?

The more I see of this the more certain I am that the front of the head has not been clamped to the block and the gasket has been leaking water/oil in and combustion gases out for some considerable time.

THe head bolts may have felt tight when you undid them but they had not clamped that gasket tightly enough to seal it.

Now - Why?

The first thought that occurs is that the block has been decked at some time and now the threads in the block are too shallow - the head bolts may appear to torque up correctly but have bottomed out in the holes.

Alternatively the front cover is now too high and the cylinder head tightened up on that before the gasket was clamped around cylinder #1 Check that the top of the front cover is level with the top of the block or even very slightly below it.

It also looks like the water transfer hole above the thermostat outlet is rusted and has not sealed or the rubber ring/short tube that goes in between the head and the block was not there - can't see it in the pictures. Was it there when you removed the head?

THere are several issues that need to be resolved before the head is freshed up and some mild porting done - be careful there too as the 2.0L valves are not so large that anything other than a bowl area clean-up needs to be done.
 

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GTJIM said:
The first thought that occurs is that the block has been decked at some time and now the threads in the block are too shallow - the head bolts may appear to torque up correctly but have bottomed out in the holes.

Alternatively the front cover is now too high and the cylinder head tightened up on that before the gasket was clamped around cylinder #1 Check that the top of the front cover is level with the top of the block or even very slightly below it.
A LOT of material would need to be removed form the head/block to cause the bolts to bottom out. This seems unlikely.

Ingestion of water and/or anti-freeze tends to have a cleaning effect on the inside of the combustion chamber/top of piston and valves that I am not seeing here. There should be noticably less carbon on cyl #1.

Based on the pic of the head gasket, it sure looks like a combustion problem to me. Extremely lean cylinder are notorious for eating away at head gaskets. The timing issue as RallyBob pointed out hadn't occured to me, but makes sense.

26 degrees advance at idle is a whole lot for a mild motor like yours. Are you sure of this?

-Travis
 

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26 degrees advance at idle is a whole lot for a mild motor like yours. Are you sure of this?

-Travis

yes i am sure, i had dennis at OGTS test it with a digital timing light at the shop in May. he was suprised too. we tried to retard the timing and would just die. also the block has never been decked. i performed the first rebuild on my car. boy did it need it. the original head was so bad the cam bearings had squiggly lines scored into them.
 
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