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3Ltr Surfs and cracking heads

Posted: Tue May 22, 2007 8:40 pm
by chrisc
Since I have one and it blew a head gasket (fortunately didn't crack the head) at the left rear I thought I might mention that the mechanic and I found there has been a design flaw with either the head or gasket or both. My recollection is hazy now since it happened a long time (at 100k) go but basically the gasket has a narrow spot whereas the head or block has a wide spot. If the gasket was a little thin then it will blow. Not if but when. We checked several different brands of gasket and found all but one (including a genuine Toyota gasket) had the same narrow bit (between a water passage and oil passage from memory). Plus they were all a little thinner at the same spot. The exception had a much thicker and wider bit. He also welded up the head to widen the land to correspond to the block.
This issue is a known problem in the US (the head cracking anyway) and in the early days Toyota used to fix it under warranty.
Stripping the engine, skimming the heads and block and reassembling with a new gasket won't necessarily fix the problem until you make proper repairs in the design flaw area - personal experience here.

I had photos of the area which clearly showed the design flaw but can't find them now.

Had no problems since except the heads had to come off again - thought it had blown again - but it was a poorly installed valve stem seal blowing massive clouds of smoke.

If I saw the gasket again I could point you to the right area.

I think that the gasket popping was probably helped by overheating at the left rear (and there are other fixes in the US which deals with this overheating issue by leaning up the water passage within the head). Mines an auto so fitting an external auto cooler, flushing the radiator, using water cooler and fitting a better exhaust could well help.

Posted: Wed May 23, 2007 1:12 pm
by IcedJohnno
From your Plural use of the word Heads I presume you are talking about the non turboed Petrol V6 3 litre motor rather than the 3 litre turboed Diesel 4cyl.
Is this correct?

Posted: Wed May 23, 2007 5:02 pm
by Petemcc
the head gaskets on the v6 4runners in nz where recalled afew years ago and fixed as far as i know. Mine definately had it done.

Pete

Posted: Wed May 23, 2007 5:03 pm
by TeLexs
Would any of you know the firing order on the 3l v6 Please Cheers Klem

Posted: Wed May 23, 2007 7:08 pm
by Mattman
According to the service manual, 1,2,3,4,5,6 and I am not taking the piss.

Right bank is cylinders 1,3,5 and left is 2,4,6

Matt.

Posted: Wed May 23, 2007 10:01 pm
by chrisc
Sorry should have stated petrol V6.
This happened a few years ago which may correspond to that mentioned above re a recall. However I bet the recall was only Toyota ? What about all the 3rd party stuff out there.
And since my vehicle is a 1990 how come it took Toyota at least 10-15 years to sort the gasket problem ?
The gasket was only a part of the problem in my opinion because gaskets work best when squashed between two bits of metal. If one of those bits is only a 1/4 the size it should have been then you can still have a potential failure site.