Coolant Leak...not the LIM gasket 4 a change

[DRCZ24]

Ok, I have a 94 Grand Am with a 3100. When I got it, it did have the notorious leaking LIM (lower intake manifold) gasket. So I took it apart and fixed that. The problem is, I bought it from a couple that were just looking 2 dump the car, so I don't know much about it. I just know when I got it home, it had the leaking LIM gasket and I took it apart and fixed that. Now that I have it back together, I have a pesky drip coming from the front of the engine somewhere. There is so much crap on the front of my engine, I can't see well to track it down. I can sorta see the LIM and it doesn't appear that it's leaking anywhere, so I'm pretty sure I've ruled that out. The leak is a pesky drip that isn't that bad and probably leaks about 100 drips a day. What else could it be, tomorrow I'm going to probably take the waterpump pulley off to rule out a leaking water pump....what else is up front on the engine that could possibly leak at all times. Looking for any ideas u guys might have.
Thanks,

Dan

[95Grand-Am]

It could be the waterpump or maybe the timing cover.

[DRCZ24]

Timing Cover....

If I could track it down to the timing cover, what are my options for fixing that? I assume I'd have to strip everything off the front of the engine and replace it???

[onefastV6]

I have my car torn down at the moment, for about a month I could smell coolant after I pulled the car into the garage, but under the oil cap there was no foam and no drips. Then I was driving and during a hard accel, the low coolant light flashed for a split second and turned off. After inspecting under the oil cap again I noticed a small dot of white crud.... so I assumed it was the early signs of a LIM leak which isn't all that big of a problem.

After tearing it down and getting ready to re-assemble I noticed seepage around the freeze plug on the rear head..... so I will be taking the head off this weekend and taking it into the machine shop for a new freeze plug. The strange thing is that is really hasn't been all that cold this year and my coolant is a 50/50 blend of dexcool and distilled water.

[IsaacHayes]

What side of the engine, by front I'm assuming by the pulleys? Water pump could be one, or if its really old then the timing cover. It's a job but can be done. Takes your time on it as it's tight in there to get out all the bolts and clean it all up. While you're in there put on a new chain and guide (I did and it made the motor QUIET). That is if it's the cover leaking. Mine was but only if you looked you could tell on the side near the firewall.

It's not the quick disconnect line that goes into the lower intake manifold leaking is it?

[DRCZ24]

In reply to IsaacHayes

It was either you or Tractorman that had some pictures up of their leaking timing cover. I dug though the old threads and my coolant is in the exact same places as that picture. So it's on the front of the engine, but on the opposite side of the waterpump. I have paper towels stuffed everywhere to see if I can pin down the source. If I determine it's not the water pump, I'm just gonna dump 3 of the GM tablets in the radiator and see what happens. At this point, I really don't want to tear it down. The car is probably nearing the end of it's life, just a couple years of service left on it. So, we'll see. Thanks for the help, I'll post an update.

[IsaacHayes]

How many miles? My engine just won't die. Unfortunately... LOL It would give me an excuse to swap a bigger engine... The leak on mine had eroded some of the timing cover away actually.

[DRCZ24]

To IsaacHayes again

I really have no idea.....I would estimate around 100,000. I was told the engine was replaced a couple years ago with an engine that had 68K @ the time...and the odo reads 161K now. I know the 60 deg v6 is a good motor despite it's problems. I have a 1988 cavalier Z24 w/the 2.8L and it has about 230K. I unfortunately had to do a head gasket on it last year...not because they went bad, but because a head bolt broke???? Go figure. All I know is when I went to remove that particular head bolt, it was barely hangin on by a thread. I had to carefully extract it from the block because it of course broke off almost flush w/the block. I got lucky and got it out somehow......I'm editing this now...I just got back in from being in the garage...I think I have a freeze plug leaking in behind my alternator bracket. Just a little bit of it was peaking out at me and I saw that the freeze plug had coolant sitting inside it. In your experience, do you think those GM stop leak tablets would stop a weeping freeze plug?
Thanks

[torq455]

no. any leak needs to be fixed right. stop leak is only a short-term fix attempt. high rpm and hot temps add pressure and may end up blowing the soft clog out. as far as the leak, i know a guy that had a similar problem. seems the 2.8/3.1's are not uncommon to have the head crack at the bolt by the alt. is that where your bolt broke?

[55trucker]

If there is a rental shop nearby that rents automotive tools try renting a coolant system pressure tester (if you can't afford to have a shop do it ). With this tool you should be able to see where the leak is (if it is only external) and how fast the pressure is bleeding off.

[DRCZ24]

To Torq455

The broken bolt on my 2.8L was on the rear head in the center of the block. That 2.8L is completely unrelated to my original post. My leak is on the 3100. I can see coolant puddled up in the freeze plug just behind the alternator bracket. I asked a service manager at a dealer tell me that the gm tablets could seal the leak up for the rest of that cars life. It's literally no more than 30-100 drips a day....not that I'm counting, I'm just guessing based off the tiny puddle on my garage floor. We'll find out this weekend.

[IsaacHayes]

Mine wasnt even a puddle on the floor I just saw the leak looking around the engine. It was enough to erode the thing though. The stop leak will probably work but I didn't want to chance it leaking INTO the timing cover and mixing with oil so I fixed it and replaced the worn and noisy chain and guide at the same time. It was a PITA but do-able. car sounds like new now.

[onefastV6]

I am pulling the head and taking it in to the local machine shop, to have it pressure tested and new freeze plugs installed. I was told $35 to pressure check and if all is good, then $3 a piece for the freeze plugs and they would check to see if the head needed resurfaced at no additional charge.

The pic below shows where my freeze plug is leaking


I do not trust stop leak tabs in any engine. A band aid fix is only going to cause more problems down the road and it will always be at a very bad time.
Do it once and do it right!

[talon2swords]

I have a 97 lumina 3100. I've already replaced the LIM with a metal Felpro about 20K back. I'm losing about a reservoir's worth of coolant every 3-4 weeks now.

I don't know where it is going. Oil looks fine. Like in another post, I was on a 2 hour long road trip 3-4 months ago and when I stopped at the gas station there was violent air bubbling into the bottle, but since then nothing.

I could replace the head gasket, but I don't know if that is it. I sometimes smell coolant in the mornings when I drive the car. Haven't checked the heater core. Got to do something soon or just park it and tear it apart later.

I am pulling the head and taking it in to the local machine shop, to have it pressure tested and new freeze plugs installed. I was told $35 to pressure check and if all is good, then $3 a piece for the freeze plugs and they would check to see if the head needed resurfaced at no additional charge.

The pic below shows where my freeze plug is leaking


I do not trust stop leak tabs in any engine. A band aid fix is only going to cause more problems down the road and it will always be at a very bad time.
Do it once and do it right!

[IsaacHayes]

if you smell coolant in the cab, the heatercore is leaking.