My wife told me that she noticed a big puddle underneath the Blazer one day when she was out running errands. I checked, and the coolant reservoir was empty and the radiator was a tad low. I filled everything back up and started up the Blazer, no leaks. I drove to work the next day and it started leaking on me. Small puddle underneath the front passenger side of the Blazer from a fast drip.

I have checked the fluid, and it isn't oil. It is slick but not oily, and doesn't seem to smell.

I can smell an oily/antifreeze type smell when the engine is running. It's actually smelled for a long time, but I never thought anything of it.

I started the Blazer up today and tried really hard to locate the drip. I CANNOT figure out where the drip is coming from, but I did notice a few things:

There is a puddle on top of the plenum next to the valve cover. I can see little bubbles forming on the valve gasket when the engine is running. I don't see any leakage, but that doesn't mean it's not happening.



Exhaust leak? Smoke was coming out of the driver's side of the engine, seemed to be near the manifold. Smelled like antifreeze.



Bottom of oil pan, and much of front differential, covered with what seems like watery oil (but oil levels are fine).



The drip is coming off the starter bolt.



Drip appears to come from the area in focus, but I can't see it.



KNOWN ISSUES: The Blazer has a new engine with around 50k miles on it, but it has a fuel issue where I must prime the pump a couple of times before it will start. Occasionally it takes a while to get fuel. I've had this problem for years, and have never had the pump tested or put a pressure gauge on the fuel rail. I have to buy a gauge because none of the auto stores in the area have loaners anymore. There is also a film on the inside of the windshield that comes right back within a few days of cleaning it off.

I've been reading other posts and from what I've read, I may have a couple of issues. I may have a leaky heater core, and my fuel spider may be leaking into the plenum and getting my oil full of gasoline? That would explain the drip and the watery oil, as well as the exhaust smoke.

Please help.

 

Well, these vehicles are notorious for the lower intake manifold gaskets leaking. My guess is that is your culprit. Have they ever been replaced? I know the engine only has 50K. They can fail at any time. Its a common GM issue from about 1996-2003. The 5.7 in my truck just failed a couple weeks ago at 175K, Im replacing them in my blazer(140K) this weekend with my mechanic friend. Its leaking a little bit, but nothing major, but im gonna do it anyway while I have time. My brothers impala also has the problem and that's a totally different engine.

 

I have a '98 with 150K and noticed a similar leak as you have pictured. I pulled my lower intake manifold and the gasket literally broke into pieces. I am fortunate no coolant got into the oil. My guess is that is what you are looking at. I would say it is a intermediate job if you have wrenched around your truck before.

 

I am dreading having to do any engine work on this thing just because of all the crap you have to remove before you can start. My Jeep is soooo much easier.

I am taking the truck to a mechanic friend in the morning, I'll see if he can confirm what you guys are saying. Thanks for the advice.

 

Its not that hard of a job 2 do yourself. When you do replace the intake gaskets get the fel pro steel gasket kit. Its like $75 at advance or auto zone. Comes with redesigned intake gaskets, new valve cover gaskets, & grommets. Have done this to all 3 of our s10 series vehicles. All of ours was leaking into pass side head. Goodluck

 

Sooo the mechanic looked at the truck for about two minutes, declared that it was leaking Dex-Cool and found a leaky heater hose. You can see it in the first picture.

I feel like such an idiot. After I replace the hoses and flush the coolant system I am going to try to clean the oil off the engine. I have a feeling I know where the oil is coming from. I think the oil filter wasn't tightened properly and some oil sprayed out over the engine. The hoses going to the oil filter are coated with oil and sludge.

 

Be sure you use Dexcool when you fill your system back up.

 

Why are there four hoses connected to the oil filter? You'd think there would only be two. I think I need to replace them.

I am going to use Dexcool. I replaced the hoses this evening, then filled the system with plain water and checked for leaks. I didn't see any. Tomorrow I will finish flushing the system and then fill with Dexcool and distilled water.

 

Film on the windshield is a leaky heater core, needs a new one... big job. Coolant leak by the valve cover sure looks like lower intake gaskets.

4 hoses on the remote oil filter mount: two go to the oil filter adapter at the rear of the engine. The other two hoses go to and from the oil cooler in the radiator.