Blown Head Gasket

[ryansm1]

Hi,

I think my head gasket has recently blown. I have a 95 Grand Prix with a 3100 in it, 140k miles on the engine (it had 137k when I bought it last year at this time).

A few days, I noticed that the heater wasn't working and that the engine would get to 210F quickly (within driving a quarter of a mile or less). The engine never overheated, though it was running hot for being 50-60F outside.

I checked the coolant level, and it was low, so I added water to the radiator until it stopped taking more. The heater began to work, and the temperatures would hang at about 160-180F. There was no coolant in the reservoir, and almost none in the radiator before I added, so I filled the radiator, and filled the reservoir up to the "Cold" marking. The next day, I checked the coolant again, and plenty was in the radiator, but the reservoir was empty.

Since it seemed that I had a coolant leak, I checked the oil levels and coolant levels daily from then. The car has not run anywhere near 210F, and has been driving fine after replacing the fuel filter on Monday.

I checked the oil today after cleaning up a spill inside, and the oil was a brown-yellow color and had a coolant smell to it. The level was well beyond the crosshatch on the dipstick. The coolant in the radiator is also a brownish color, smells like oil, and has some gunk in it. No white smoke coming from the exhaust or signs of leaking under the car or inside the engine bay.

So I suppose that it is showing signs of a blown head gasket. I've been looking around, trying to gather information about the repair required, and it looks to be expensive to have it done in a shop, but not so bad to do it myself.

I am out for Christmas break now until January, and would have plenty of time to work on the car (especially since I can't drive it). From what I've gathered, it usually takes people a few days to do it the first time around. My father has done head work on V8s, but isn't so inclined to allow me to work on this one. I have a good bit of mechanical inclination, and a lot of free time, so the only thing I am really missing is the shop manual.

If it's not a bad idea to try it myself, which shop manual should I buy? I have heard that Helm's manuals are the most comprehensive, but they are pricey.

What tools would be required for the job (torque wrench, etc. I have access to most of the normal tools used for maintenance)? What about the price I would be looking at to do it myself?

My father hasn't completely ruled out the idea of allowing me to do it myself, but he wants to see what the mechanic down the road would be charging before allowing me to do anything.

I've tried to include all the necessary information I could think of. Any help provided is greatly appreciated.

[pepsi_coke]

Odd. No signs of smoke/smell ? First thing is to find "why" you believe she cracked. Replace the leaky hose and whatnot.

You need a "heads up" gasket set and head bolts, because the head bolts strecth and you can't reuse them. Head gasket set and Bolts run around $130 for the package.

Any idea which head it mite be? If not, do a compression check on the engine and find which head. Once head is off, take it to a machine shop and check for cracks and the usual, making sure it is not warped or nothing.

Also, once oil gets into coolant lines .. they become weak and prone to "crack" .. so you'll need to invesigate that.

Hope any of this info was useful, and Im sure if I said something wrong, someone here will correct it.

I used a $15 Hayes manual when I replaced the front head on an 89 Beretta .. but the actual GM service manuals are always a good thing to have handy. You can check www.ebay.com for those.

Good luck

[DEI37]

If you're not blowing any white smoke, I would tend to believe that a lowr intake manifold gasket is the trouble here. Do that first. Once you get down to it (which you'd have to do to do head gaskets anyways) look at it, and see if there are evidences of coolant/oil leakage in the right rear corner. That is the most trouble prone area.

[ryansm1]

Thanks for the replies.

Pepsi_coke:

There haven't been any odd smells coming from the engine compartment; the only thing out of place is the oil smell in the coolant and the coolant in the oil. I don't really know which head it might be (or if it may be what DEI37 suggested), as I haven't had the chance to do a test.

If can get all of the tools I need to work on it, but how difficult is the job? Is it more time-consuming or just difficult?

If the job isn't really difficult and is more time-consuming, I have plenty of time to work. I would just need to convince my dad that I wouldn't destroy the engine.

Thanks again.

[TheProfessor]

my brother had the same exact problem and it turned out to be the LIM

[treeZ24]

i am in the process of troubleshooting that exact same issue as you describe. what i've found after tearing down the heads (and above) off the engine was that on the right rear (close to #1cyl) was a large buildup of gunky oil beside the water jacket and sitting on the head behind where the pushrod moves.... indicates water seepage so i think that the LIM gasket was leaking

almost the exact same symptoms that you have with the exception that i always have heat.. but when i shut off the engine 10 seconds later i have no heat..i'm just throwing on new gaskets all the way up and hope they last long enough to get my hybrid engine completed

[ryansm1]

Well, my dad had been consulting a mechanic about it, and he wanted $1100 ($600 parts + $500 labor) to do the job, so my dad told me to just start looking for a new engine.

Since we most likely won't be using the current one, I suppose now I can tear it down and at least take a look at it. I think I am going to get a shop manual and just tear it down.

Thanks again for the help.

[geoffinbc]

I gurentee you just have a typical intake manifold leak. $100 or less in parts and it is fixed. It is rare that you loose a head gasket on these engine. Leaking intake gaskets however happen on 90% of the engines.

Dont pull the engine just replace the gasket and put new oil in it. If you wish run some seafoam through the crankcase if there is any sludge buildup.

[ryansm1]

I've started taking the engine apart. I don't think we'll be buying a new engine any time soon, so I have plenty of time to work with it.

The only reason this engine would be pulled out would be if a new one was dropped in. My father doesn't seem to want to have this one repaired, and thinks it would be cheaper to go with a new engine (instead of having the mechanic repair it; if I can repair it, that would be great).

I've been wanting to do the L67 swap (or even the 3400), so if he doesn't trust me to fix it, I am going to be pushing for one of those instead of another 3100.

If he does end up buying a new engine, I'm still going to try to fix this one. It has to be worth something.

[geoffinbc]

LOL L67 yea that will be cheep

The intake probabally wont even cost you $100. Just do it. Make sure you have a torque wrench. It is very improtant that you torque the manifold right.

[TheProfessor]

I've been wanting to do the L67 swap (or even the 3400), so if he doesn't trust me to fix it, I am going to be pushing for one of those instead of another 3100.

If he does end up buying a new engine, I'm still going to try to fix this one. It has to be worth something.

just fix the intake gasket
and dude do you realize how much stuff other that then engine you need to do an L67 swap not to mention all the drewbacks of one of those motors
the only good thing about them is the SC

[ryansm1]

LOL L67 yea that will be cheep

Yeah, I know it's not a cheap swap, but I wouldn't have to take all of the cost by myself.

Hopefully I'll have it broken down soon; I'll try to pick up the parts I need on Monday.

Thanks again for all your help. I appreciate it.

[DEI37]

I've been wanting to do the L67 swap (or even the 3400), so if he doesn't trust me to fix it, I am going to be pushing for one of those instead of another 3100.

If he does end up buying a new engine, I'm still going to try to fix this one. It has to be worth something.

just fix the intake gasket
and dude do you realize how much stuff other that then engine you need to do an L67 swap not to mention all the drewbacks of one of those motors
the only good thing about them is the SC

While I realize that this is a 60* board, there isn't any need for L67 hating like that. Stock for stock, the L67 has a shitload more power, gets better fuel mileage, and has MUCH better aftermarket support. I have one sitting in the garage, awaiting installation in to my '97 CS. It's a more reliable engine, for sure. I've been through more than my fair share of 3.1's.

[TheProfessor]

i wasnt hating on the L67 i was just trying to let our buddy know that you dont just get one and drop it in its not that easy
besides ofcoarse more power they have an M90 on top lol
and i dont think the aftermarket is as good for an L67 as its cracked up to be
and yes maybe they are more reliable than 3.1s but not the new gen 3 660s
maybe its just my opinion but iron wedge heads with shrouded valves, oddfire crank, harmonic balancer, and balance shafts arent on my list of thing to get when im looking for a performance motor, not to mention the plastic parts that warp
now dont get me wrong either they are good solid motors better than most

[DEI37]

OK...sorry if that came off a little harsh...didn't mean it that way, honest. As far as the aftermarket, I know of two places that have a broad selection of just about anything you can want. I agree with you that the heavy all-iron construction is ancient, but it is reliable. Balance shafts are also another HP sapper, and I do agree that it'd be nice if that was a 60* engine.