Changing the oil pressure switch

[swettysblazer]

Like the title says, I'm tackling this this weekend. The old K5 has a pretty serious oil leak and I'm pretty positive the sender is leaking. It seems like a pretty straight forward job, the only thing I am worried about is taking the distributor out to get to it. Is there anything that I need to worry about before I do this? Should I make sure the engine is at TDC on cylinder 1? Or just mark it with some paint and drop her back in?

 

[sweetk30]

no need to pop dist out .

and make sure you hold the brass angle adaptor for the switch . if you don't 90% time these snap off flush in the block then you will be unhappy .

 

[dyeager535]

You already have the parts?

There is a later switch/sender combination that you can use, which simplifies wiring and replacement, if you think this will be an issue again in 20 years.

 

[swettysblazer]

Nope, gonna buy them today. I work at a parts store so they're easy to come by

 

[jeff in co]

I did this on the K5 and also my 04' yukon 8.1L. If I recall correctly, the Yukon was pretty hard and tight, K5...not as bad. Just take your time. I did not remove my distributor either.

 

[swettysblazer]

Well, that wasn't it. Pulled it out, put the new one in, and still leaking. Looks like the motors coming out

 

[sweetk30]

full clean down with degreaser first .

then cheep mirror on a stick and check for leak point .

is it constant with engine running ?

or is it a ozzing / slow leak ?

were do you see the oil ?

 

[swettysblazer]

Constant with the engine running... Its really pouring out. The oil looks to be coming out from above the oil filter.

 

[sweetk30]

there is a sensor there sometimes . and if not a gally plug . check that to see if this is the problem .

possible double oring on the filter and not actualy from engine ?

 

[swettysblazer]

I'll check that. And no, I drove the truck for about a week and then all of a sudden it started.

 

[sweetk30]

as a mechanic for years I have seen 2x orings a few times . even had 1 that never leaked from last oil change to the 1 I did . someone else never checked for it stuck .

others pop as soon as you fire them up and leak .

even seen a wrong oil filter for a dodge on a ifs4x4 88-98 style gm last till 500 miles before oil change due before it poped off from wrong thread size. happen to wedge in frame is how I knew it was wrong filter.

 

[4xcrazy]

Right above the oil filter? up past the head or actually right above the oil filter.

Is this on the 91 you have in the sig line? and does it still have the oil cooler and adapter on it. Possibly the o-ring seal used on those. They get old and brittle.

 

[swettysblazer]

as a mechanic for years I have seen 2x orings a few times . even had 1 that never leaked from last oil change to the 1 I did . someone else never checked for it stuck .

others pop as soon as you fire them up and leak .

even seen a wrong oil filter for a dodge on a ifs4x4 88-98 style gm last till 500 miles before oil change due before it poped off from wrong thread size. happen to wedge in frame is how I knew it was wrong filter.

I'll check it tomorrow, but I checked it before I put it back on. Don't hurt to check again though.

Right above the oil filter? up past the head or actually right above the oil filter.

Is this on the 91 you have in the sig line? and does it still have the oil cooler and adapter on it. Possibly the o-ring seal used on those. They get old and brittle.

It isn't coming up on the head.... And it is the 91. I'll check to see, to be honest I'm not sure.

 

[4xcrazy]

What I meant was, is it dripping down and leaving oil on the head on it's way to the ground, like maybe a valve cover gasket or even those pesky intake end seals. I have had a few vehicles in the past where it'd leak from the rear of the intake where it mounts to the engine block,,, where those stupid little rubber gaskets are supposed to go but we all know better than to use them.

Sounds like it's time for a couple of cans of brake cleaner in the general area and run it for a day or shorter to see exactly where it's coming from.

 

[swettysblazer]

No, definitely not valve cover gaskets. Already checked that. I wish I could run it for a day- i am afraid to run it for five minutes, that's how bad the leak is.

 

[sweetk30]

few cans of brake parts cleaner to get all oil off.

then fire it up and look for the leak .

and if that scared keep fire killer handy

 

[4xcrazy]

If it's leaking that bad, I'd say it's actually being pumped out from a pressurized area, like a leaking plug or those gasket seals for the oil cooler setup.

 

[swettysblazer]

I agree. I got under there, but I still can't tell where it's coming from. I just can't see well enough up where it seems to be coming. Definitely not the rear main. I looked by the oil cooler, and I am suspecting that this is where it is coming from.

 

[diesel4me]

I'd look over the cooler hoses and the crimp fittings real good--when I took the hoses off my 6.2's oil cooler ,the crimp collars looked perfect on the side facing me--the other side facing the block was completely GONE!--just white corrosion where it once was!....I was very surprised it wasn't leaking,or had not let the hoses blow off the fittings...those aluminum fittings can develop a pinhole too,and let a nearly invisible stream of oil squirt somewhere far away,fooling you into thinking the leak is elsewhere..

I was also puzzled to find no oil was in either cooler hose,I even blew air thru them and it seemed nothing had flowed thru them in years--if ever!..I used a loop of 3/8" copper tubing to join the two cooler ports with the right fittings and it hasn't seemed to miss having the cooler one bit..I swear the oil pressure went up a bit too..

The oil cooler hoses are cheap crap on many GM's..many a good engine was blown up because one failed and the driver kept going till it was out of oil,which is about 30 seconds to a minute at highway speeds..