Tip & How-To about Mazda B-Series Truck

Tips for making your cars headgaskets last with those aluminum heads.

These days most small cars have aluminum heads and the number of blown head gaskets that I have seen has increased a lot.
Rule number one if you want your head gaskets to last is to not let these engines overheat. With the iron heads you could let the heat gauge run into the red with no real lasting or catastrophic damage - most of the time.
With these aluminum heads you cannot do that. Whether you run out of water due to a leak or your 10 dollar thermostat sticks shut, you have got to pull over and stop the engine. If you don't, that 10 dollar thermostat could cost you over 900 dollars.
To cool the engine as fast as possible just raise the hood with the engine off. DO NOT POUR WATER OVER THE ENGINE!!! That is very very bad and could easily junk your engine.

Ok lets say that for some reason you do blow a headgasket because the bolts were not originally tight enough or some other reason.
You have some options as to repairs. You can go used from a junkyard or new. Used will be lots cheaper but harder to find a good one. Always take the used head to a reputable machine shop to be checked. Almost all used heads are already warped to some degree. Less is better and one that hasn't been milled before is lots better. Your machine shop should know how to bend aluminum heads so that they are really close to being straight. If they dont then the cam bearings wont be straight for the came. Remember both sides need to be straight. top and bottom. In most cases it is possible to straighten it enough that the cam area will not need to be rebored oversize, and the bottom can just be touched up with the milling machine.
Next important bit is to not use Felpro gaskets. Use Corteco head gaskets on aluminum heads. Felpro works great on iron heads but most of the headgaskets I have seen blown were Felpro and very few were Corteco and of those few Cortecos blown, the engine was grossly abused where some Felpro ones had no history of abuse. Just trust me on this one.
Now here is a tip that your mechanic may not like at all. Some of these gas engines have the head bolts right at the edge of the head. Usually two at each end and we wonder why all the heads are warped? Lets think about this a bit. If the torque specifications for a head say 160 foot pounds and the distance between head bolts is roughly 4 inches what is happening at the ends of the heads where there is half as much surface area clamping the gasket? Yep you guessed it. There is nearly twice as much pounds per square inch squishing the gasket at the ends. With time and heat this will warp the head.
Now the part your mechanic may not like. I don't torque those 4 head bolts as much as I do the ones towards the center of the head. If it says to torque the bolts to 160 foot pounds then that's what they get except the 4 end ones will only get say about 145 or close to 10% less. Now I did not actually do all the math to compute the torque necessary to keep the pounds per square inch even for the end bolts but rather estimated. If you are or know an engineer that can compute that feel free to let me know the results.

-Consaka

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car overheating and mixing water with oil


You have blown the head gasket. Also, you may have warped the head if it's aluminum which will happen due to ignoring the issue of overheating...which eventually caused the "blown head gasket". So, it sounds like you have 2 issues to resolve. 1) Why was it tending to overheat? Stuck thermostat, water pump issue or??? 2) Repairing the cylinder head or replacing it if warped badly, if your lucky it's just a blown head gasket. Allowing a overheating vehicle to be in service without solving that the overheating can lead to MANY other expensive problems.

Feb 12, 2014 | 2006 Fiat Pininfarina

1 Answer

cylinder head torque specs for 2.o liter


Can't give you the numbers but don't forget that the exact sequence is critical too, especially on small engines and aluminum heads which can warp easily and spoil the new head gasket. Some engines require 3 successive rounds of increasing torque in the right order. I hope you had the head (at least; block should be done too) checked for flatness since with a failed headgasket, it may have had an opportunity to warp and therefore require resurfacing.
Good luck-

Dec 10, 2009 | 2006 Suzuki Forenza

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if my car has some white smoke coming out the tail pipe and smell of anti freeze, but no milky in the oil. does that mean head gasket. it is a 1999 chrsler seebring


If you have steady thick white smoke and it smells like anti freeze it is most likely the head gasket. The head gasket can fail in different areas. If it has white smoke it failed between a coolant passage and the combustion chamber. If the oil is milky it failed between the coolant passage and an oil passage. Just because the oil isn't milky doesn't necessarily mean that the head gasket it's blown.

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i have oil in my engine coolant reservoir as well as my radiator and im not sure what caused this. is this something that can be fixed?


A head gasket leak (blown head gasket) is highly likely. ($200)

Check your oil dipstick If it contains a milky fluid, that is water mixed with the oil. A sure sign of a blown head gasket.

Other symptoms of a blown head gasket include:
1. White smoke and excess water dripping out the tailpipe.
2. Overheatinmg engine
3. With radiator cap off, steam and water will erupt, sometimes violently.

Whichever tailpipe has the smoke is the side that the blown head gasket is located.

... sorry ...

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1 Answer

little flakes of aluminum in the cooling system


If you are seeing bubbles either your head gasket is blown or you have a crack in the head or block

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