Head Gasket on overhead valve engine V6

[Leo]

1991 Pontiac Sunbird V6 Commonly blow headgaskets above 170,000km I hear. I am at 125,000km but I will require a head-gasket eventually. The engine is a V6 Overhead Valve. Are overhead valve engines easier to do a headgasket on due to the fact that the cam is not in head? Also the timing chain is hooked to the cam and is in-between the cylinder banks so do i not have to worry about timing?

Any thoughts would be appreciated greatly. I know this isn’t exactly a easy procedure but what do I need to remove likely? Alternator, power steering pump, intake manifold, exaust manifold, spark plug wires, and fuel injector rail?

Topic

[Ingvar]

http://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c1528003b988

yours is down towards the page bottom

[David]

First of all if you do a regularly service on your car and check water/oils on a weekly basis, that ‘Commonly blow headgaskets above 170,000km’ might not happen to your vehical but if it does a workshop manual of the Pontiac is the best thing you could invest in for your car.

Follow the manual and you will be fine, the hardest thing (and it really isnt that hard) is to make sure your have the crank at tdc and the cam/s at the right timing marks before you put everyhing back together.

[Leo]

for the autozone page what does “Note the position of the pushrods for assembly” Mean? Thanks for this post ukrkoz.

wokko7 I hope your right about not blowing a headgasket. I don’t neglect my vehicle as many do. What should I replace to prevent headgasket issues? Thermostat would be a good start i’m guessing. I own a Factory service manual and a Cylmers.

[David]

Head gasket issues are normally todo with over heating, and other factors but over heating is the main issue.
Keeping an eye on your temp gauge and good service history are really all you need to do.
I have a habit of replacing all fuilds on a six monthly basis and (touch wood) I dont have any dramas with my vehicals I own.

[Daniel Beaird]

[quote=”knookle89″ post=136267]for the autozone page what does “Note the position of the pushrods for assembly” Mean?[/quote]

It means the pushrods in this engine are different lengths. The intake pushrods are shorter than the exhaust.

Also, I have seen more of these engines ruined because the intake gaskets fail causing coolant to get in the oil ruining the bearings. I honestly have only seen one case of this engine having head gasket issues and I think even that was from overheating caused by the intake gaskets failing.

[Leo]

Intake gasket change is alot simpler i hear that Head Gasket. How do I know if the coolant is going into the oil? Besides complete destruction to bearings? My oil changes have been very normal yet far, no discolorations yet. My temperature gauge stays fairly low.
What tools for intake manifold? 1/2 torque wrench ok?

[Leo]

Do i need the Tech 1 Scan tool? It says to use it everytime you disconnect the battery 😆 I’ve literally done this 100x without issue. Its says you need it so the IACV can figure out its position. Really…..

[Daniel Beaird]

[quote=”knookle89″ post=136292]Intake gasket change is alot simpler i hear that Head Gasket. How do I know if the coolant is going into the oil? Besides complete destruction to bearings? My oil changes have been very normal yet far, no discolorations yet. My temperature gauge stays fairly low.
What tools for intake manifold? 1/2 torque wrench ok?[/quote]

First indication would be low coolant level. Also look at the oil fill cap and dipstick, check them for milky sludge that will indicate moisture in the oil. The dipstick should not have ANY of what will look like water droplets in the oil. If any of those are true I’d suspect intake gaskets leaking coolant into the oil.

Another quick check is to look where the intake meets the head on the front and rear of the engine. Look for trails of coolant, this will indicate that the gasket has failed enough not only to leak externally but internally as well.

GM has an updated gasket and bolts for these engines. The gasket is all aluminum with rubber seals instead of plastic or thin metal with rubber seals. The bolts have loctite on them but you can also just clean up the old ones with a wire wheel and apply loctite yourself.

You shouldn’t need any special tools to do the intake. 1/2 inch torque wrench is way overkill for this job. At the most you might want to have a 3/8 drive torque wrench for the rocker arm bolts.

Either way from what you are saying in your posts it sounds like your engine is ok and doesn’t suffer from either head gasket issues or the intake gasket problem.

[Leo]

Ok I hear you Beaird. I sounds like I shouldn’t mess with the intake manifold until there’s a issue or 170,000km. This engine doesn’t seem that hard to do a intake gasket on this engine in comparison to ericthecarguy Nissin 2.4L, wow!!!

[Author]

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