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Hows it going.

NOTE: QUESTIONS BELOW IN BOLD FOR THOSE LAZY PEOPLE

My dad got an old 91 mazda 929 with a DOHC v6. It started running like crap (no pickup, no power, engine shaking) the other day so i diagnosed spark plugs after finding out my dad hadn't changed them in ages.

So i take out the plugs on the drivers side bank and they turn out worn and there was also some residue on the leads. I change them and then move over to the passenger side bank.

I take off the intake pipe, get the leads out and they have a blown, wet, gooi looking substance on them. All three plugs on that side came out with this crap. I changed the plugs with new ones anyhow.

Then i start looking for other signs of this substance to confirm that it is oil and water mixed. i find some in the airbox where the blow by has brought it in. the coolant level was low a few days earlier and this was topped up, as was the oil.

The car runs much better with the new plugs.

SO NOW I'M PRETTY SURE MY DAD HAS A BLOW HEAD GASKET.

WHAT I WANT TO KNOW IS:

1: IS A REBUILD DEFINATELY INVOLVED?

2: CAN JUST THE GASKET BE CHANGED WITHOUT A FULL BUILD?

3: WHAT HAPPENS IF THE CAR IS STILL DRIVEN?

4: IS IT CHEAPER TO DO A TRANSPLANT THAN GET IT FIXED??

any help would be great

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Not really sure about the rest, but my other car was very low on coolant, just after I had changed it, and the car was running hot. It was so bad on the way home from work I had to leave my car on the side of the freeway, came back the next day to find the passenger window smashed. :)

Turned out to be the head gasket (not exactly sure what had happened), but all I did was change one hose that had a slight leak, and put a thing called Seal Up through the radiator system. It cost about $8, and stopped the leaking, and now it runs fine. This is more of a shortcut, as the problem is still there, but it is now just sealed.

Anyway, if the coolant has gone "missing", then that would be the problem. Idon't see a rebuild happening if there has been no other engine damage, and you could just change the gasket or go the sealer. As for the car still being driven, it all depends on how the car actually runs, but something does need to be fixed no matter what. Good luck.

thanks for that. i'll look into this seal up stuff. I'm just converned that the galleries are going to get covered in this oil/water crap, and everything will need to be cleaned. Maybe some sort of engine flush could do it.

will get the car looked at by a pro on monday.

Till then, any other feedback would be of a great help.

where did you get this seal up stuff??

I just got it from Repco, any sort of accessory shop like that would have it. Read the label & see what it says. It's 500ml I think, but it's a dull brown colour, it took me a while to find lol.

However, I'm pretty sure mine was just a crack, so just see what the proffessional says, it could be better to wait. If it needs to be driven on Sunday just drive like a grandma & take it easy!!!

there is another kind of seal up stuff. It's a solid that you break up and chuck into your radiator.. how it works.. im pretty sure that it sort of dissolves, runs through your engine and then solidifies somehow when it gets to the leak, which seals up the gaps..

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