I tried pressure testing my radiator again today because the water was low. I don't see any leaks. How long should the system be able to maintain pressure? I'm loosing maybe 1psi in 10 minutes. Is that enough to be worried about? I do have an overheating problem. Could that mean i have a blown head gasket? Also, my oil looks a lot dirtier than i remember.
No one wants to be the bearer of bad news. Sounds like you've got a blown head gasket. If you have a compression tester (you can borrow them from an Auto Parts Store), I'd test each cylinder. Good luck.
by dirtier do you mean brownish? probably water. i'd try to drain the oil and slowly remove the plug. if it has water in it it will usually start to seep out first since the oil is thicker.
I've taken the radiator completely out now. I plan on taking it to the shop to be rodded it out. When I was working on it, I saw a leak in the back of the block. I'm guessing its one of the freeze plugs again. They were leaking before and I tightened it down. That could be the slow pressure leak. The oil was not brown but more grey than I remembered. I plan on changing it soon, so I'll look for water then.
Rick, how would I test each cylinder? I'm guessing it would screw into each sparkplug hole. Would the radiator need to be on for that?
To do the comp test. Do 1 cyl at a time (pull the coil wire to be able to crank it over and not start). get a remote starter button to jump the soleniod or have someone in the car turn it over. Crank it over a few times to get the highest pressure right it down put plug back in then go to the next cyl they should be close pressure to each other with in 10 psi. The throttle should be held open during the process to let the motor pull air in. If I missed somthing I` m sure sombody will add to this. Hope this helps and you dont need the RAD in cause it wont be running
Yes, you use a gizmo like this (again, your local parts store should have one for you to borrow): A remote starter switch is very handy to use when performing this test (you'll want to use it when you tighten your rockers also): Screw the thread into the spark plug hole. Put some oil on the o-ring first to help it seal. Crank the engine over - allowing the cylinder that you're testing to be "compressed" 3 times (you'll hear it). Record the pressure move onto the next. Compare the results of all the cylinders. Something else you could do (a quick preliminary test) is remove the plugs, while you're looking under the hood, have someone crank the engine. If any water spews out of the cylinder - you'll know you got head gasket problems. This indicates the gasket seal has blown into the water circulation system and is allowing water to get into the cylinder. If you're compression test indicates two adjacent cylinders with zero compression, that is an indicator that the gasket has blown a seal between two cylinders. With your oil being a gray, you're pretty much guaranteed it's a blown head gasket. Like grbmaverickmo said, if you find a cylinder that has an obviously lower pressure (usually more than 10psi) that's an indicator of where the gasket is blown. FWIW, the 10psi, in my experience, indicates ring blow-by in that cylinder - not necessarily a blown head gasket. Good luck.
