johnfin

I did the clutch about a year ago, replaced everything including the rear main seal, used the special tools and put it in right but I still am getting a leak onto the H-pipe. No its not the sender unit on up leaking down. Does anyone other then GM make a real decent rear main seal?

00pooterSS

iTrader: (40)

The cam sensor will cause a leak at the very back of the motor too. It's at the top behind the intake and the o ring is actually a few inches down so when it leaks it leaks into the bellhousing area and will look like a crank seal leak.

slogo

^^^ What this guy said^^^ That is the first thing I look for on these engines, when
its leaking in that area.
And don't think to just replace the oring, oil is usually coming out from where the
wire connects into sensor, meaning oil goes through the sensor. I think about cutting them
open on every one I do to see how but never do.

johnfin

Where exactly in the cam sensor located?
I put it up on ramps and took a look. Its all wet with motor oil, not dextron. Side and top of engine are dry. Slave is new and not leaking. Left o2 sensor is dripping with oil, probably from the harness. I think its migrating from the bell housing back to the H pipe, it was wet. I will put some uv dye in the oil and check it. Pretty sure its the rear main.

slogo

Behind the Intake Manifold, right in the center, next to it is the Oil Pressure Sending Unit.
Best way for me to check is with a mirror on a stick, and a flashlight.

johnfin

I have looked back thete with a scope. Dry. Now oil does not go up without help and the sensor is down in the block. Explain how oil would come shooting out of the sensor hole.

badassbu

iTrader: (2)

Maybe the rear cover is leaking.Did you have the rear cover off?

johnfin

No because you need an alignment tool.

slogo

Well if it is Dry back there then it is not either Cam or Pressure Sensor.
The last few Cam Sensors I have replaced have had Oil where Wire connects to sensor, inside the female part of Cam Sensor,
so I am guessing something internally started leaking with the sensor and oil started pushing it's way up the sensor and that is where it can get out, thats just my last few months of
personal experience, I have replaced lots of rear main seals and rear cover seals as well.
You don't have to have an alignment tool for the covers, put the crank seal in the cover,
make sure crank is clean, lube seal with oil, slide it on, before you put the final squeeze on the screws make sure cover is square with the bottom, been doing it that way for years
with no problems.

johnfin

If the can sensor leaks its behind the rear cover which seals the rear of the engine. You would have to have both leak. Iam using dye tonight to trace it.

johnfin

I used the uv dye. Not coming from slot in bell housing. Its dripping from the starter bolt up high on engine. No oil from heads up. Drips down the joint between engine and belhousing. Some of the cross main bolts look wet but this starter area is dripping bad. Any ideas?

big hammer

If it's a drilled crank with a freeze plug, it's possible the plug got damaged when the the pilot bearing was changed causing a leak.

johnfin

Nice thought, not sure if its plugged or not...probably screwed it up if it had one......BUT.....its not leaking from the hole in the bottom of the bell housing.

johnfin

Took starter out and flywheel is bone dry. So if it was the crank plug, rear main or cover, wouldnt it be wet in there? And if the rear cover leaked i would think it would go into the bellhousing and out the slot which its not. Unfortunatly i think i need to pull the transmission.

big hammer

If it's all dry and clean in there I would tend to think you have no issues in there.

Valve cover or PCV leak somewhere?

johnfin

I can only see the back of the flywheel and the teeth, not the clutch pressure plate. There are slots on the side of the bellhousing where if the rear cover plate leaks it could come out the side.

gagliano7

If you didn't put sealant on the flywheel bolts that could be your problem. They holes go all the way through. The flywheel bolt holes will leak oil if not sealed.

johnfin

I used the threadloc per the gm service manual but never the less, if that , the main seal or the pilot hole was leaking i would think it would sling it everwhere. Teeth were bone dry.

00pooterSS

iTrader: (40)

When the cam sensor o-ring leaks it LEAKS INTO THE BELLHOUSING not up and out. The o ring seals a few inches down from the valley cover height and there is an opening in the back of the block. It's possible it could leak through the connector but I've never seen it on a cam sensor, just the oil sending unit.

I have seen many cam sensor o rings go bad and put oil into the bellhousing.

It's a $25 repair that takes about half an hour. Try it and see what happens, it's easily worth the money and time.

00pooterSS

iTrader: (40)

See if this pic helps