shiners780

That is indeed the header bolt you see.

How's this pic? The coolant appears to be coming from up under where the yellow arrow is pointing to, maybe just a little to the right of it. The coolant runs down right where the red arrow is. It's really hard to get a good pic with everything in the way there.

billthe3

Yeah, if that is where the leak is then it looks like it would have to coming from either the head or block. Any leaks from the waterpump would be going down from that, so it'd probably be hidden behind the rear belt cover.

Chris White

That pic has me a little stumped. From the angle that you took it it looks like the leak is above the head / block interface (headgasket). Really weird to get a leak above the head gasket area, especially near the exhaust ports.
Get an inspection mirror in there to see if you can see exactly where the leak is coming from.
Maybe its just an illusion thing – if it is not above the head / block line then it would be the head gasket – and a very odd place for that leak.
And yes – everybody needs the pressure tester!
BTW – does you engine still have the stock head gasket?

MPD47

Yes Chris it is still a stock headgasket. Was one of the questions I asked Jim on the phone the other day.

OriginalSterm

What causes the black flakes in the coolant though? Is it just deteriorated hoses junk?

shiners780

Yep, stock headgasket, 95k miles, last 3k or so on track.

It's really hard to see back there exactly where it's coming from. It appears to me that it's coming from the waterpump gasket right at the top of the waterpump. Then running down to the spot shown in the pic above where I drew the red line. I can shine a tiny flashlight back there and it appears damp right up at the top of the waterpump where it meets the engine. Of course, I'm only seeing it with one eye while bending in some freaky contortionist position trying to see it. I entertain the neighbors if nothing else.

In the first pic, it is damp where the white arrow is pointing, between the waterpump and engine. Coolant runs down and drips off where the red line is.

In the second pic, you can see the coolant drip circled in yellow, after it runs down where the yellow line is. It drips about once every 20 seconds at 14 psi.

The radiator is dripping about once every 3 seconds at 14 psi. Do I need to remove it and have it tested to find the leak?

shiners780

Pressure now at 13 psi. Radiator leak drips once every 5 seconds. Waterpump leak (if that's what it is) drips once every 2 minutes.

What to do, what to do...

My dilemna is that I have an event in under 3 weeks that I don't want to miss, then a big break in my track schedule.

Musche

As far as the radiator goes, maybe you will get lucky and either the drain plug or hose bib for the small hose that goes to the reservoir just need tightened/resealed. Be careful though, the end tanks are plastic and tend to crack if you over torque, especially with the hose bib. These are plastic as well. I keep a spare one in my tool box.

nitehawk951

A lot of great info on this thread, but I just can't stop laughing at ehall's avatar. I wish I was that creative.

shiners780

Thanks Musche. I checked the drain plug, the coolant temp sensor, and all 4 hoses going into the radiator, no sign of dampness around any of them.

It appears to be coming down the seam between the end tank and the main part of the radiator itself on the driver's side. That seam between the two is damp all the way up to where the fan shroud is. Maybe if I pull the fans I can see where it's coming from a little better.

Would either a leakdown test or compression test help to rule out the headgasket? Which test would be most conclusive? And lastly, do any of you Rochester guys have the testing equipment so I don't have to drag the car somewhere to have the testing done?

Thanks again for all the info guys.

Geneqco

I thought this might be helpful for diagnosing HG leak.

Exhaust gas test: A BHG will normally leak exhaust gasses into the cooling system. This makes the radiator water acidic, and this can be detected by a chemical test. In New Zealand the piece of equipment to do this is called a Tee-Kay tester. To use it you run the car with the radiator cap off, and suck the water vapour from the radiator through the tester. A BHG will show up as a colour change in the test liquid. This test is very sensitive to exhaust gasses, and will easily prove the existence of a BHG. However it is also prone to returning false negatives - showing no problems when in fact the motor has BHG’d.
Radiator pressurisation test: Under normal conditions your cooling system should pressurise to the release pressure of your radiator cap. This pressure should be maintained for as long as the car remains warm (ie running or soon after shutdown). Similarly if you artificially pressurise the system while the car is cool, it should hold that pressure for some hours. Using an air compressor you can raise the pressure of the cooling system to a bit above normal running pressure, and leave it to see whether the pressure drops. If it does drop significantly within about an hour, then it is likely that there is a BHG or a cooling system leak. If the pressure does drop, start the car after leaving it pressurised for some time - a BHG will allow coolant into the cylinders, and this should produce a large amount of steam out of the exhaust as soon as you start the engine.
Cylinder pressurisation test: This is the reverse of the radiator pressure test. It involves pressurising each cylinder through the spark plug hole, and looking to see whether the level of the radiator water rises. This is not a particularly accurate test, but will show up a badly blown head gasket. To do the test effectively each cylinder must be at Top Dead Centre to ensure the valves are closed - if they are not the compressed air will just pass out through the intake or exhaust.

shiners780

Thanks Geneqco. Anyone in Rochester have a compression tester I could use?

TRP951

Hey shiners if you need a headgasket I have a stock one sitting in my garage brand new. And some of the seals from the headgasket kit minus the cam cover seals. If you need it you can have mike pick it up

Keithr726

Geneqco you are the man! I'm having a problem where there is brown crap on the walls of my coolant tank but not in the liquid itself and every month or so my coolant level drops and inch.

What about using PH paper to check acidity in the coolant?

shiners780

Thanks Tim, let's hope I don't need to take you up on that offer.