Why do fords blow head gaskets?

[ILLaViTaR]

I know ford E series blow head gaskets like anything but what is the general reason for this?

Like if it was a radiator block that could happen to any car.

So why do E series blow head gaskets like crazy?

[Nikked]

from my knowlage, its because the block is Iron, and the head is Alloy. They expand at different rates and over time file away the gasket.

[Tanksenda]

ILLAVITAR
My EL blew a head gasket on a trip. I was sitting on 100 with even throttle when a great puff of smoke blew out of the exhaust and the engine started to missfire. To cut a long story short, when I got home I discovered a head stud had broken and on removal of the head, the gasket had blown right across the broken head stud hole and leaked water down the side of the engine block. I had the head machined and cracked tested by a local engine reco mob who also supplied me with new after market head studs. Apparentely, genuine head studs are crap and have a habit of breaking without any reason. That was three years ago and Ive had no trouble since.

Nikk O' lass
Just about every car on the road has Alloy heads and Iron blocks, but nothing blows head gaskets like an E series Falcon.

[Christiaan]

1. Keep the engine cool, and don't warm up to very hot, then cool down fast..

2. Keep your radiator serviced, and make sure your cooling system is in check..

3. Don't run the car lean, and don't let it ping

[glenneaux]

I thought one of the main contributors was the head studs stretching and snapping releasing pressure on the head?

I know when my head came off there was at least 1 broken bolt.

[aussiblue]

Another contributing factor was that very early on in the series life Ford decided it needed to change the head gasket so it blocked off two passages in the front of the head/bock to make the cooling system work more effectively. While this worked, it also means that the coolant is prone to work under the layers of non multilayer steel gaskets at these points eroding the gasket away near the blocked off passages. So use the AU multilayer steel gasket to avoid this.

Also once an aluminium head is overheated it also softens so that it develops head flutter with the torqued up head bolts working into the head at each end over time so that the ends of the Head can bounce or flutter on the block. That is why it is also important to do a hardness test before replacing the gasket; ACL make and sell a cheap go-no go hardness indicator you can use for this test. Head bolts with larger diameter tops also help a little but can't compensate for a softened head.

Lastly like many modern cars the top of the radiator is lower than the head so it very easy to get an air lock in the system if is not filled correctly and carefully or if there is a small leak elsewhere. Ford in there factory manual also says that these engine rely in part on thermosyphoning to keep the coolant moving (i.e. hot coolant rising cold coolant sinking) not a good idea in an engine that may already have a marginal cooling system.

Most EA and EB's also had a lot of casting sand left in the block which works its way into the bottom of the radiator blocking it and causing overheating and a blown head gasket (I got half a bucket of sand out of the NB block when I stripped it down for a rebuild and i had already had another 1/2 a bucket in various replaced radiators).

Lastly the on EAs. EBs and Eds the old fan clutches have habit of dying and the replacement fan clutch stockist transporters don't always store the new ones the right way up (and if it self service customers examine them and put them back on the shelf the wrong way up) so the ax doesn't partially drain out before you buy your replacement. A good reason to switch to EF thermo fans.

[Christiaan]

Originally Posted by aussiblue

Another contributing factor was that very early on in the series life Ford decided it needed to change the head gasket so it blocked off two passages in the front of the head/bock to make the cooling system work more effectively. While this worked, it also means that the coolant is prone to work under the layers of non multilayer steel gaskets at these points eroding the gasket away near the blocked off passages. So use the AU multilayer steel gasket to avoid this.

Also once an aluminium head is overheated it also softens so that it develops head flutter with the torqued up head bolts working into the head at each end over time so that the ends of the Head can bounce or flutter on the block. That is why it is also important to do a hardness test before replacing the gasket; ACL make and sell a cheap go-no go hardness indicator you can use for this test. Head bolts with larger diameter tops also help a little but can't compensate for a softened head.

Lastly like many modern cars the top of the radiator is lower than the head so it very easy to get an air lock in the system if is not filled correctly and carefully or if there is a small leak elsewhere. Ford in there factory manual also says that these engine rely in part on thermosyphoning to keep the coolant moving (i.e. hot coolant rising cold coolant sinking) not a good idea in an engine that may already have a marginal cooling system.

Most EA and EB's also had a lot of casting sand left in the block which works its way into the bottom of the radiator blocking it and causing overheating and a blown head gasket (I got half a bucket of sand out of the NB block when I stripped it down for a rebuild and i had already had another 1/2 a bucket in various replaced radiators).

Lastly the on EAs. EBs and Eds the old fan clutches have habit of dying and the replacement fan clutch stockist transporters don't always store the new ones the right way up (and if it self service customers examine them and put them back on the shelf the wrong way up) so the ax doesn't partially drain out before you buy your replacement. A good reason to switch to EF thermo fans.

Great write up, thanks for that! :

[aussiblue]

... so the ax doesn't partially drain out before you buy your replacement. A good reason to switch to EF thermo..."

Oops "ax" was meant to be "wax".

[revcore]

Are there any mods involved with fitting a AU head gasket to a ED motor or is it a straight fit?

[aussiblue]

Straight fit.

[aussiblue]

E series are also fussy about thermostats and in my experience work best with a dual acting thermostat (also called a skirted, bypass and reverse poppet valve thermostat) complete with a air bleed hole and jiggle pin. This is what they came with from the factory.

See these links for some discussion on the pros and cons of skirted thermostats:

http://www.are.com.au/feat/techt/thermostat.htm
http://www.expeditionlandrover.info/Thermostats.htm
http://www.vtr.org/maintain/stag-cooling.shtml

Others claim to get better results with single acting thermostat and drilling bleed holes in those that have the half circle or v cut notch in the rim of the T stat valve plate (hole a closed normal T stat up to the light and you will see it) . I think a factory bleed hole with the jiggle pin fitted is better and dual acting ones work well provided they also have the bleed hole and jiggle pin. At the end of the day I think we can agree, whatever our view on the best thermostat, that E series engines are fussy about thermostats and having the air bled when filling with coolant (including bleeding air through the T stat).

I agree with the comment in the first link

Non-Bypass Thermostat In A Bypass Application -
In this situation there is no secondary valve that will block off the
bypass port when the engine warms up (Figure 4). This will cause
hot coolant to continue to circulate through the engine without
going to the radiator. The engine will run hotter than required and
may cause a failure of other components in the cooling system.

[Jason[98.EL]]

could be a desighn fault by ford

[sexr6tasy]

Dont forget jesus also hates e-series so that contributes to some head gaskets blowing

[floppy]

Are there any mods involved with fitting a AU head gasket to a EA motor or is it a straight fit?

[Grechie]

Originally Posted by floppy

Are there any mods involved with fitting a AU head gasket to a EA motor or is it a straight fit?

straight fit.

[Gunns]

Could be the fact that ever block from ea to au that I have worked with has never been square. I have seen up to 80 thou out front to rear left to right. The gasket will never seal evenly and it is only a matter of time before it gives in.

[3.9from hell]

Originally Posted by Gunns

Could be the fact that ever block from ea to au that I have worked with has never been square. I have seen up to 80 thou out front to rear left to right. The gasket will never seal evenly and it is only a matter of time before it gives in.

coincidence! lol

[joker4]

aussiblue pritty much said most of it, also make sure that the air flow is also getting to the radiator, eg, crap build up between the radiator and condensor
and keep a eye on that temp gauge