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fullysick_86hatch
03-20-2007, 05:04 AM
firstly let me say hello,i have an 86 3g hatch a20a engine i bought with a blown head gasket i have changed it but three weeks on it has blown again after i changed the water pump, i torqued the head down at 10 20 30nm sequence the deck and head seems straight and replaced the thermostat,im in process of changing the head gasket a second time
at idle the temperature seems to climb and the fan only stays on for 30 sec
there seems to be no leaks in cooling system and i have bled the air also
one thing that i done was top up the radiator and resevoir with coolant
could it be too much coolant in the system
what else can i do to avoid replacing gasket a 3 time
thanks

2oodoor
03-20-2007, 06:05 AM
from the information you provide I would look in to:
ignition timing check
radiatior restriction
thermostat possibly installe backwards or defective part
colapsed hose, look for hose sucking inwards to itself
head could be damaged from previous overheating
Make sure heater is on when you bleed air from system,

MessyHonda
03-20-2007, 08:35 AM
also try to get a honda or felpro gasket

2ndGenGuy
03-20-2007, 10:44 AM
Did you have the head checked at a shop? If it's even slightly warped, that would be why it's blown again. You might even have a cracked head. These things usually happen when you experience a blown head gasket.

You can check with a straightedge, but that's not precise enough IMO. I'd have a pro check it out. I had mine decked and pressure tested for $60. It's worth it to have the assurance. Plus the surface comes back perfectly clean for an excellent mating surface for the head gasket.

If the cooling system is good, and it's still overheating, there is something wrong with the head. ALSO you may not want to reuse your old head bolts. When you have an aluminum head, and iron block the bolts are designed to stretch to prevent head gasket failure. This is because of the different heating and cooling rates of aluminum vs iron. If you use stretched bolts you may have the right tension on them, but they're not truly even across the head.

88Accord-DX
03-20-2007, 07:35 PM
When you remove the head, make sure it is cooled down, never remove a head when it is hot. One mistake people do when changing a head gasket, is not loosening the bolts in the proper order. (from the outside in, crisscross, back & forth) Opposite from torqueing senquence. The head needs to be checked for warping & pressure tested as good insurance on a head gasket job. The bolt holes need to be cleaned out real good, no oil or coolant can be in them. It is wise to use new head bolts, even though their not TTY bolts. (torque to yeild)
Get a metal head gasket & use copper gasket spray on both sides. The bolts need a light coat of oil on them before installation. The torqueing senquence is essential in proper sealing on a head gasket.

fullysick_86hatch
03-22-2007, 04:49 AM
ok thanks guys i'll let you know how i get on with the head after i take to a machinist

fullysick_86hatch
03-23-2007, 08:43 PM
just took the head of the block there was no gasket failure it still looked ok
however one thing i noticed was when i took the bolt out the one next to the oil control valve was full of oil and water mixture,
so i guess that the head may be cracked somewhere near there.
ill try and find one at a wrecking yard
are A20A2 and A20A4 parts interchangeable eg cylinder head?.

Ichiban
03-23-2007, 08:53 PM
Make sure you verify that the head is bad, and it is not a cracked block.

cygnus x-1
03-24-2007, 07:12 AM
just took the head of the block there was no gasket failure it still looked ok
however one thing i noticed was when i took the bolt out the one next to the oil control valve was full of oil and water mixture,
so i guess that the head may be cracked somewhere near there.
ill try and find one at a wrecking yard
are A20A2 and A20A4 parts interchangeable eg cylinder head?.

All A20 engines use the same head. I would take the head to a shop and have them check it for cracks before you go get another one. But from the symptons you described it doesn't sound like the head gasket is bad. What led you to believe the head gasket is bad? Was it losing coolant somewhere but not leaking onto the ground?

C|

MessyHonda
03-24-2007, 07:38 AM
All A20 engines use the same head. I would take the head to a shop and have them check it for cracks before you go get another one. But from the symptons you described it doesn't sound like the head gasket is bad. What led you to believe the head gasket is bad? Was it losing coolant somewhere but not leaking onto the ground?
C|


yeah only the cams are different from fuel injected and carbed cars

AccordEpicenter
03-24-2007, 07:41 AM
make sure the head is not warped either

fullysick_86hatch
03-25-2007, 03:52 AM
cygnus,coolant was in the engine oil,when i took off the head the gasket was still good no breach of water into the oil gallery's through the gasket from what i could see,i now have a cylinder head from a reconditioned engine i am going to install its off a a20a4 injected i have to install the cam and gear because it looks like the distributor mount looks different to mine
also have another prob i took the timing belt wheel off without putting it at TDC and i think the cam pin that locks the timing belt wheel dropped in behind the timing cover and onto the crankshaft wheel.

cygnus x-1
03-25-2007, 06:23 AM
Ahh, I see. The distributor is different between carb and FI engines but you don't have to switch the cams. You just need to swap the one end cap that the distributor mounts to. Just make sure you put some RTV betwen the cap and head to keep it from leaking oil. The distributor area is a common spot for leaks. And whatever you do only use a cam with the rockers it came with. Or buy new rocker arms. Also keep the rockers in their original locations.

C|

fullysick_86hatch
03-31-2007, 03:25 AM
well its all done,i had a problem with starting the car i had the engine set at the exhaust stroke instead of compression stroke TDC took me a while to figure that one out.
temperature gauge still sits on half is that normal?
or should i pull thermostat out
what can i do to make the fan stay on longer?

MessyHonda
03-31-2007, 07:21 AM
you should replace your thermostat with a Honda OEM one...it was like 12 bucks over here and it solved my overheating problems.

fullysick_86hatch
04-01-2007, 02:59 AM
who messed around with the title
i didn't write that

A18A
04-01-2007, 03:06 AM
who messed around with the title
i didn't write that
its a april fools joke, all "gas" words have been censored to "sexsexsex"