Head Gasket woes

Post by **PaulVW** » Mon Jun 16, 2008 6:09 pm

Hi There, long time no see, don't know if any peeps remember me?!

anyway, I am going to the national on Friday

but my car started running really rough yesterday, and it turns out the head gasket has blown.

now, this is the 4th time it has happened in just over a year, and last time I got a garage to do it, as I thought my tools were not acurate enough!

1000 miles later it has gone again! everything was done correctly, skimmed, re-ground, checked with a straight edge, re-torqued at 500 miles etc etc. The garage cant explain why it has gone again, they are going to have the head off and have a look tomrow, and if it all looks ok, put a new gasket on. and torque it down extra tight.

this is where I want your help, how tight should it go? last time it was done down to 45ps 60? 70? i don't want to do it any damage really, but I can see no alternative.

Post by **alex_holden** » Mon Jun 16, 2008 6:14 pm

Did you use the Payen head gasket? The cheaper one you can get isn't as good quality.

This topic tells the story of my head gasket trouble and how I eventually cured it.

Post by **polo2k** » Mon Jun 16, 2008 6:16 pm

Doesnt sound good! Maybe its worth looking for a different head, if that solves it then yippe!, if not then maybe substitute the block and do it by elimination.
I cant see any reason why it should be doing headgaskets that often presuming she is being treated correctly when running.

p.s. Are you based up north? just asking because i used to know a guy up there who used a similar username on the VW forums

Post by **PaulVW** » Mon Jun 16, 2008 6:28 pm

yes it was the more expensive gasket (I should have shares in the company at this rate?) did not get new nuts is the only diffrence.

If it fails this time, I am thinking along the lines of a different engine. I dont have a spare head or block!

ps. no I am from kent, VW is the initials of my surname, not the car!!

Post by **polo2k** » Mon Jun 16, 2008 6:34 pm

oh oops lol

If its the same garage each time then I would be tempted to try another. do you know if they are tightening the studs in the right order? is everything else in the right place and not hitting anything?
i.e. if the down pipe is hitting the chassis leg then over time It could have adverse affects.
also it could be worth flushing the cooli8ng system to within an inch of its life as localised hot spots could cause deformation of the head.

Post by **PaulVW** » Mon Jun 16, 2008 6:49 pm

I did it myself the first 2 times. I trust the garage complety, they are used by many members of the east kent branch.

flushing the cooling system might be an idea I guess.

Post by **mrbenn** » Mon Jun 16, 2008 6:55 pm

Definitely flush the cooling system thoroughly. Might be an idea to take the water pump off and check it looks ok.

Post by **polo2k** » Mon Jun 16, 2008 7:45 pm

also check that there is flow through the corrigated bypass hose becauser this sometimes gets clogged as its fittings rot

Post by **PaulVW** » Mon Jun 16, 2008 7:51 pm

polo2k wrote:also check that there is flow through the corrigated bypass hose becauser this sometimes gets clogged as its fittings rot

it was replaced last time the head was off!!

Post by **Kevin** » Mon Jun 16, 2008 8:01 pm

I know its unlikely but has the block been checked as well.

Post by **ims101** » Mon Jun 16, 2008 8:03 pm

polo2k wrote:oh oops lol

If its the same garage each time then I would be tempted to try another. do you know if they are tightening the studs in the right order? is everything else in the right place and not hitting anything?
i.e. if the down pipe is hitting the chassis leg then over time It could have adverse affects.
also it could be worth flushing the cooli8ng system to within an inch of its life as localised hot spots could cause deformation of the head.

Hi sorry to jump in on this one but my HG has gone (not been done for a long time tho) but reading your post what is the correct order to tighten the nuts? and what touque would you recomend??
Trying to get it done so I can get to the National at the weekend

Thanks

Post by **PaulVW** » Mon Jun 16, 2008 8:04 pm

yes, with a straight edge, and other high tech gadgets the garage had!

Post by **Kevin** » Mon Jun 16, 2008 9:09 pm

OK to tighten the nuts down if you are looking at the head with the thermostat housing to your left there are 5 nuts on the far side numbering from the housing 9-5-1-3-7 on the opposite side are 4 nuts again from the housing 8-4-2-6.
They should be loosened & tightened in numeric order, when replacing everything should be done finger tight then tighten them all a quarter of a turn with a spanner then use a torque wrench in stages until 40lbs for the cylinder head nuts & 25lbs for the rocker pedestals is reached.

Post by **bmcecosse** » Mon Jun 16, 2008 9:24 pm

But later versions of this engine with the SAME studs etc are torqued to 45 ft lbf, and if you fit the even later Mini head studs and use the later 'flanged nuts - then 50 ft lbf is the torque to use. However - I suggest there is indeed a problem with the block - especially if it always blows in the same area ? Meantime - clean it all v carefully - and fit thick washers under each head nut to spread the load - and go to 45 ft lbf in easy stages - but first make sure each head stud is firmly located in the block - and not just hanging on by two threads!!

Post by **PaulVW** » Mon Jun 16, 2008 9:32 pm

yes, it always goes between 3-4

Post by **alex_holden** » Mon Jun 16, 2008 9:36 pm

PaulVW wrote:yes, it always goes between 3-4

Perhaps the first time it went, the hot gasses eroded some of the surface of the block away in the thin area between cylinders?

Post by **ims101** » Mon Jun 16, 2008 11:03 pm

Kevin wrote:OK to tighten the nuts down if you are looking at the head with the thermostat housing to your left there are 5 nuts on the far side numbering from the housing 9-5-1-3-7 on the opposite side are 4 nuts again from the housing 8-4-2-6.
They should be loosened & tightened in numeric order, when replacing everything should be done finger tight then tighten them all a quarter of a turn with a spanner then use a torque wrench in stages until 40lbs for the cylinder head nuts & 25lbs for the rocker pedestals is reached.

Cheers for that Kevin.

I've just dug my workshop manual out from an old box in the garage and reading up as its been some years

Post by **MGFmad** » Mon Jun 16, 2008 11:15 pm

The words 'head gasket failure' make me cringe as I have an MGF as my daily drive which has a Rover K series engine and we all know how prone they are to HGF - is the A series engine similar in this respect?

When I think back a few years my 998 cc Mini blew its gasket between cylinders 3 and 4. At least it will be quicker to fix than a K series

Post by **PaulVW** » Tue Jun 17, 2008 12:19 pm

the garage have got back to me, they have examined the head and block in great detail, and the head has a hairline crack, and the block is "straight, but not perfect"

I have 2 options really, new head and block, or new engine.

they are going to put a new gasket on again (free of charge), and tighten it down to 60lbs, and hopefully it will get me to the national and back! (I have AA if not ;) )

Post by **ASL642** » Tue Jun 17, 2008 2:14 pm

Theres a really good autojumble at the National (Sat am) - you might be able to pick up a second hand head.