"New" Truck - first two leaks found

[sgr60]

Just a few days with my "new" '84 K20 and I've already got some questions.

Now that the truck is sitting in a nice clean garage (rather than the field I bought it out of) I've noticed two leaks so far - one oil and the other power steering fluid.

I took a photo from the top down of the area of each leak. Any thoughts on what the culprits might be?

Oil leak:



Power steering leak:



Thanks!

[mrolds88]

Not sure about exactly where its leaking on the steering, but on the engine, I'm looking at the rear intake seal and valve covers. I would suggest you either power wash or take it to the car wash and blast the leakage off and recheck afterwards.

[sgr60]

Originally Posted by mrolds88

Not sure about exactly where its leaking on the steering, but on the engine, I'm looking at the rear intake seal and valve covers. I would suggest you either power wash or take it to the car wash and blast the leakage off and recheck afterwards.

I definitely need to get it cleaned up - in addition to the oil, there is 30 years of grime caked onto all of the drivetrain components underneath.

Is it OK to "blast" the water in that area - so close to the distributor?

[mrolds88]

Yes, just be careful. If need be, cover the cap with a plastic bag.

[LilD]

Power steering could be like many others I read about researching the issue with mine. Input shaft seal.

[sgr60]

I've made some headway on identifying the oil leak. I've gotten the area cleaned up quite a bit, and also changed out the valve cover gaskets along with doing an oil change. It looks like I now have two leaks - it might be just one, but it looks like two.

First, you can see oil dripping here - the plug wires are new, so that oil on them has dripped onto them from somewhere. It looks like it might be coming from the plug with all the wires coming out of it. What is this? Two photos below:





Next, there is fluid dripping down around the transmission bell housing (I just changed that fluid today as well) - I can't tell if it's engine oil from somewhere, or it's a leak from the tranny. Thoughts? Photo below:



Thanks for the help.

[Just call me Sean]

You've got oil top to bottom. Most likely valve covers.

[sgr60]

I put in new valve cover gaskets and the smoking that I was previously getting from oil on the exhaust manifolds has stopped - so I was thinking that the leak there had stopped. It's possible that I'm wrong, but I was thinking the problem was elsewhere.

[mattybilt79]

That round plug should be the oil pressure sender. Looks like rear main is leaking if its coming out of bell housing. I would pull the dust cover off and see if the flywheel and clutch are wet. Could also have oil coming from intake to block seal at rear of motor and possibly the distributor holeand still possible valve cover leak if gasket slipped when you put them in or if valve covers are bent out of shape. The steering leak is more than likely the input seal just about every truck I've owned has leaked there.

[sgr60]

Originally Posted by mattybilt79

That round plug should be the oil pressure sender. Looks like rear main is leaking if its coming out of bell housing. I would pull the dust cover off and see if the flywheel and clutch are wet. Could also have oil coming from intake to block seal at rear of motor and possibly the distributor holeand still possible valve cover leak if gasket slipped when you put them in or if valve covers are bent out of shape. The steering leak is more than likely the input seal just about every truck I've owned has leaked there.

Curious - why does the oil pressure sender have so many wires. My oil pressure gauge only works intermittently as it is... Maybe I should replace that?

The dust cover was actually out when I went under to take the photos - I pushed it back in with a screwdriver - now sure how long it was loose for.

The oil leak is very slow, I may just live with it for the time being, I have a lot of other things I need to do before I can think about what would be involved with replacing the rear main seal.

As far as the steering leak, I'm going to replace the steering shaft and power steering gear next weekend, so that should solve that - that's a much bigger leak. Seems like a pretty straightforward job.

[mattybilt79]

I don't know why some have that 3 wire plug while others have 1. Seems like a lot of stuff changed in the mid 80s with electrical vacuum and other systems on Chevy's and gmcs.

[Just call me Sean]

That three wire oil pressure sensor is for the choke. Yes, it's for the choke. The one for the gauge is behind the distributor and has only one wire like all the rest.

[sgr60]

Originally Posted by Just call me Sean

That three wire oil pressure sensor is for the choke. Yes, it's for the choke. The one for the gauge is behind the distributor and has only one wire like all the rest.

Interesting - it just gets more complicated as I get deeper into it

Guess I'll have to keep digging and try to better understand the wiring diagrams...

[Just call me Sean]

It's pretty simple, I'm used to tracing fuel injected diagrams. Plus I went through all this on my '83. None of that was hooked up, some of it still isn't.

[donut]

The oil on the bell housing could also be coming from the rear of the intake manifold.

[motornut]

some times the valve covers need to be flattened out before reusing it.
(the edge/lip the gasket sits on)
make sure the oil sensor it self isn't cracked or loose leaking down the back.
do you have a working PCV valve?
covers sealed to tight will blow it (gasket)back out,with blowby

[mrolds88]

With the oil on the bellhousing and the plug wires, especially the way they are routed, I still believe you have a rear intake leak.

[sgr60]

I was planning on replacing the intake manifold down the road, so if that's the source of the leak then hopefully I'll be able to take care of it.

[Your41Plague12]

The round plug above the oil filter is for the oil pressure switch. Like previously mentioned, it's wired into the choke circuit. It won't let the electric choke close unless there is oil pressure, essentially just to let you leave the key on without the choke engaging. It my have to crank for an extra second until the choke sets on the first start of a cold morning, but it's a good idea in theory. Mine was disconnected when I got my truck, but I hooked it back up and it works great.