Head Gasket Symptoms Question

wbhgrace · Post by **wbhgrace** » Sat Jul 04, 2009 1:28 am

81 Rabbit 1.6 na with 11 mm head bolts -

30kmi flawless miles on re-ring and bearing job (with a new head gasket) - started running rough and billowing white smoke at a stoplight. Didn't overheat, just happened all of a sudden, and I shut it off within a few seconds. It overpressurized the cooling system and spewed coolant out of the reservoir tank cap. After it was towed home, I started it and drove 20 feet into my driveway (more white smoke).

I pulled the head off - the bolts all seemed tight and needed roughly the same amount of torque to loosen.

There's coolant lots of places: 1 quart came out of the crankcase before any oil started flowing out, there was a cup or so in the air cleaner casting and more in the intake runners. There were a couple tablespoons in cylinder #4 and a little bit in one of the head bolt holes on the rear side of the engine.

The block and head are both still nice and flat. The head gasket doesn't have any obvious breaches in it, but i can maybe see one area in the corner near cylinder 4 where it looks a little different from the other areas.

My question is, is all this symptomatic of a head gasket failure, or should I be worried that the block might be cracked? I've heard that 11 mm 1.6 blocks are prone to cracking, but I don't know where to look or how to tell.

Any advice?

libbybapa · Post by **libbybapa** » Sat Jul 04, 2009 2:12 am

Did you drain the coolant out of the engine prior to removing the head?

wbhgrace · Post by **wbhgrace** » Sat Jul 04, 2009 2:20 am

Yes - but I only drained it at the bottom hose by the thermostat. And I removed the 3 hoses attached to the head.

I believe some coolant did drain out of the head when I was pulling it off. The car is parked nose-up on a fairly steeply inclined driveway. Are you thinking maybe some coolant left in the head could be the source of the coolant in cylinder 4 and in the head bolt hole? That could be.

Quantum-man · Post by **Quantum-man** » Sat Jul 04, 2009 7:13 am

If you have a compression tester, reassemble and test. Thast way you can find the spot/cylinder.

libbybapa · Post by **libbybapa** » Sat Jul 04, 2009 9:18 am

If you don't pull the thermostat prior to removing the head, then when the head is removed, coolant can get lots of places when the head is removed. Really mucks up diagnosis.

Andrew

wbhgrace · Post by **wbhgrace** » Sat Jul 04, 2009 11:01 am

Oops.

There was coolant in the air cleaner casting and intake runners too. It was there before I took the head off. Any ideas how that happens?

libbybapa · Post by **libbybapa** » Sat Jul 04, 2009 11:52 am

I can't think of an easy way for coolant to get into the intake runners other than a crack between the intake and coolant channel. Even with the head gasket blown, it would be difficult for the coolant to get past the valves and into the intake manifold. I'd definitely get the head pressure tested.

81rabbitdiesel · Post by **81rabbitdiesel** » Thu Jul 09, 2009 6:07 pm

I would definitely get the head pressure checked as Andrew said. I just replaced my headgasket for the 2nd time. The first time I naively thought that the head/block looked good and used a straight edge/feeler gauge and both checked out ok. Reassembled and got a pressurized cooling system immediately. Removed head again and had it pressure checked and it was ok.

After further inspection at the machine shop there was a spot slightly lower on the head surface between a coolant passage and precumbustion chamber.. My previously "reconditioned head" it was determined had been resurfaced with a belt sander..gugh.. The guy at the machine shop said he fixed it and I was skeptical but I just got her put back together today and she's doing fine knock on wood