cactusfarmer

I want to hook a vacuum guage to my GA16DE and check for a blown gasket among other things. Where is the best place to hook it up, which vacuum hose should I remove and hook it too. Ok, ok, I know, I should know this stuff, but I haven't had a chance to play with this thing yet. Any help would be greatly appreciated.

 

GA16DE200sx

Pull the hose off the fuel pressure regulator and hook it up there.

cactusfarmer

Do I put a tee between the fuel pressure regulator and the intake manifold collector and hook the guage to the tee, or just leave manifold part disconnected and hook the guage straight into the fuel pressure regulator?

Also, what kind of numbers should I be looking for on the vacuum guage?

wes

You want to tee it in for the most accurate reading. You can tee off ANY hose that comes directly off the IM.

Stock you should pull 18-20inhg

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cactusfarmer

Thanks, I'll give it a shot and see what I come up with.

 

cactusfarmer

I teed it between the IM and the fuel pressure regulator and it was only pulling 11 inhgs. I have a small leak on my throttle body gasket which might account partly for the low reading.

So I went ahead and did a compression test I got:

Cylinder 1 Dry 180 adding some oil 210
Cylinder 2 Dry 182 adding some oil 228
Cylinder 3 Dry 180 adding some oil 192
Cylinder 4 Dry 175 adding some oil 195

When I took out the plugs they were wet, it was hard to tell if they were wet from water and coolant or oil, but a little on the rusty looking side so I'm thinking water. But they didn't have that nice thick chocolate milk look you usually get when oil and water mix in your engine. Also when I stuck my fingers in the tailpipe they got wet after a few seconds. There doesn't appear to be any oil in the radiator or water in the oil otherwise.

Although it runs great, it eventually overheats, so I think all this adds up to a blown head gasket. I just replaced the head with a reworked head, so I probably screwed it up when I put it back on. So it looks like a redo on the head gaskets, oh boy.

wes

HMM COmpression #'s are aweful good and consistant for a blown hg. You can use pressurized air in the cylinders and look for bubbles in the coolant at the top of the filler neck. You have to do this individually as you will have to rotate the motor so the valves are closed to pressurize each cylinder, or you could just remove the cams. This is a GREAT way to look for a blown HG.

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cactusfarmer

Yeah, I was thinking about that. I probably should track down a hose and fitting and give that a shot before I go through the pain of pulling the head again. Would you pull all the plugs and then test it, or pull one plug at a time. It would seem to me if you pulled all the plugs and air came out one of the other plug holes, that would indicate a blown head gasket too.

wes

I would guess you won't be able to hear it leak out yoo much or perhaps it is not leaking all the way into the other cylinder...

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