overheating

[Bonnefied_GM]

Okay, so for some reason, my car has decided to start overheating. Thought it seems the issue MAY have been creeping up on me, I had issues just the other day when we had our first summer-like day (nearly 100 degrees). I noticed while I was driving that the temperature was getting past the 200 mark and the last day or two it maxed out between the 200 mark and the next line (whatever temp that one represents). Not to mention that when I get out of my car and check the situation, it's leaking/dumping coolant all over the ground. I checked the reservoir and the level still reads well above the full cold/full hot marks (always does, regardless of temperature). I noticed what looked like a dry streak of coolant just under the radiator cap and a little puddle of coolant along one of the ribs right underneath of the cap. I looked at the motor and didn't see and coolant leaking from the LIM area or UIM area, or even the coolant elbow (all were perfectly dry). However, the crank sensor is SOAKED, including the wiring. Any ideas? I'm hoping it's not a serious issue. Hell, today was a lot cooler at only 70 degrees and I drove lightly and it still did the same thing. Would a new radiator cap and 180 degree t-stat be a good start to seeing if the issue resolves? The only thing I've changed was the cam sensor the other night (over the weekend), and a new EGR valve/gasket a week or two ago.

EDIT: this may be why my car bogs too, since the crank sensor is soaked completely

[bill buttermore]

Overheating may be caused by low coolant in the engine. Check the coolant level in the radiator in the morning when the engine is cold before you start it up. Should be full to the top. The recovery tank will not function properly when there is a significant leak in the system, and so, is not always the best way to check coolant level. Lots of places on that end of the engine could be causing a leak - water pump, radiator hose, coolant elbow and more. There is a photo somewhere....I'll go look...

[Bonnefied_GM]

Well, I DO remember that I checked under the radiator cap before starting the car to leave work this afternoon. I couldn't really see any coolant in there, or it was pretty low to the point of just being out of the light (I was away from the sun anyway).

EDIT: in fact, I think it's had a very small leak for quite some time. It's possible that as it got lower, it just got hotter and eventually got low enough that the coolant heated up enough to boil out.

[bill buttermore]

Well, no coolant in the engine will cause it to overheat! Hope you didn't damage anything. Never put coolant into a hot engine - can crack cast parts, pretty much all the important stuff in there. Here are some places where leaks commonly occur on the L-36:

[Bonnefied_GM]

Well, all I could see for sure was that the crank sensor area was soaked and not really anything else.

[bill buttermore]

After you re-fill the radiator and engine with coolant when the engine is cold, get a mechanic's mirror and a flashlight. Drop the mirror down to reveal the parts shown in the photo above. Shine a light on the mirror. The light will reflect onto the dark engine, illuminating it and allowing you to make a better inspection.

The coolant is running down to the bottom of the engine from somewhere above and dripping off of the CPS. Water pump is one likely candidate. Wiggle the water pump pulley to see if it is loose. May have to remove the belt tension to do this. If pulley wiggles, the pump needs to be replaced.

[Bonnefied_GM]

Well, I'll refill with coolant before heading to work tomorrow and keep a jug on hand if I should need it. At least if nothing else, I can KEEP it from overheating until I figure out and fix the issue. I'll have to check that stuff tomorrow though.

[Bing]

If you do need a water pump I have the series III still up for grabs, 20$ plus shipping to your address. All you would need to do is buy the metal gasket for it. Just PM me if this is your problem and are interested. Here's some pics:

[Bonnefied_GM]

I was considering a Series l since I heard in some previous threads that they are a better casting or design.

[wjcollier07]

They are. It uses a cast impeller instead of the series 2's stamped impeller. You'll need to get a Series 1 pulley to go with it though. That'll require a junkyard run, or someone here selling you one who might have one (I have a few, but I've no idea where they might be)

Better yet..I have a new Delco Series I pump and pulley together. I know where those are. PM me if you want to buy them off me.

[Bonnefied_GM]

Well, I checked the coolant this morning before work and it was, of course, low. I topped it off and drove to work without it overheating once. Did the same after work after checking and topping off and no overheating, so I know it was due to low coolant from a leak. I have it in the shop now to have the crank sensor replaced (I really didn't want to bother with removing the crank pulley, so I'll let good ol' Bob do it). Figured since I just started having the leaking issue, I'd have him look at it and go from there. My thought was that it'd be stupid to have him put a new crank sensor in only to have the coolant keep leaking onto it and ruin a new one. He'll probably call tomorrow and let me know what's up. Either way, I'll make sure she's done up right!

[Bonnefied_GM]

Bob called and confirmed my initial suspicion that the water pump was the source of the leak. Since it's at his shop right now, I'm letting him do the work. So, a new water pump and new crank sensor (sensor supplied by me) and then I should be able to pick it up. Hopefully tomorrow.