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Low oil pressure reading, too much oil, seized at crank

10K views 7 replies 4 participants last post by  bsrome 
#1 ·
Long time lurker, first time poster. And I'm very, very sorry for the long post, but I want to be as detailed as possible.

Let me preface with sharing that I'm not a mechanic or car buff. But I'm a quick learner and am not intimidated by working on this issue (or related auto issues). I just don't dive in to anything until I've done extensive research :geek:

Know issues & backstory:
1: My engine has a knock in the mornings when it's cold. I'll crank my motor, and it would knock for either just a few seconds, or up to the first mile, even after letting it idle for a few minutes.

2: I also have a slight coolant leak. Nothing major, but I keep a few quarts of universal coolant with me just in case. I've had to add ~3 bottles of it to my reservoir over the past 6 months. I don't believe this to be related, but again, I want to be thorough.

3: It's worth noting that my tachometer has stopped reading over the past few months. And in cold weather, such as this week, the speedometer barely registers, if at all. I've been relying on a Android app to keep up with my speed. Related, I thought that the oil pressure gauge may also have gone awry...

4: Lastly, and perhaps most important, the mechanic that performed my last oil change said they had to flush my engine as the oil was very sludged up... as if it were well overdue, despite it being maybe 200 miles over.

Thursday: My oil pressure gauge was showing my oil pressure at ~20psi. On my way to work the other day, while idling at a red light, it dropped to ~8psi, which is when I got really worried. The light changed, and I slowly accelerated, eyeing the pressure as it crawled back up to ~20psi. I checked my oil when I got to work & I'm sitting at around 5.5qt. I put a quart in, meaning I'd be a little heavy. I understand this as not recommended, but as I assumed I was blowing a little oil off, or just burning it, a tad bit extra would not be an issue.

Friday: Same thing in the AM. ~20psi, mild knock which stopped a few seconds after starting. Drove to work (16mi), and caught the same red light 0.5mi from the office. Same thing happens- oil pressure gauge reads ~8psi, slowly accelerate through light, and get to the office.

Lunch time comes. It's about 32F outside, which is warmer than it was in the morning. I go to my truck, crank it, and it immediately died. I sat there for a second, thinking maybe the cold was the issue, and tried it again. It tried to start, and I felt the engine stutter/rock for half of a second as it died.

Auxiliary / power still works, though my clock as been reset. Assuming it was oil related (maybe from having too much?), and being just shy of due for an oil change, I decided to embark on that adventure for myself for the first time, as I couldn't very well take it to anywhere. When I removed the oil plug, initially, nothing came out. There was a blob of sludge on the tip of the plug. After a few seconds, it finally started draining. It seemed a little viscous, but that may be the cold (32F). Again, I'm not a mechanic, so I could be way off base here. I quickly ran in to a brick wall when I couldn't get the filter off, and then I ran out of daylight.

Today: I'm taking my wife to work in her car, then taking her car to my office to continue my oil change (after snagging a slip wrench to get the filter off). I'll finish my oil change (using 5:1 inexpensive oil to transmission fluid, with plans on another change ~250 miles in), and hope that my issue was somehow related to that. I'll also have her car there and can try jumping it off, though I still don't believe the issue to be in relation to anything electrical... but I'd rather know than assume.

Outside of these things, I don't know what else to do besides get it towed to a mechanic. Any suggestions/ideas?
 
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#2 ·
After more digging, the coolant leak and oil sludge may be related. Apparently, there is a known issue with this particular engines and these symptoms caused in relation to a Castech cylinder head. While I hope that isn't the issue, if it quacks like a duck...

I'm at work now, and going to go finish my oil change. I'll keep updating this post on the off-chance that it helps someone else down the line.

Oh, and here is some information on the Castech casting issues (identifying, symptoms, pictures, etc): http://ww2.justanswer.com/uploads/Blueg ... ss_5.3.pdf
 
#3 ·
Yep, I dont have any real personal knowledge about this but I remember recently reading another thread on a really similar issue as this. I think the outcome was coolant leaking into the oil and basically freezing when it got too cold....thus gelled oil. I also think there was a service bulletin on this as it was a known issue for some trucks.
A question to try to narrow this down are:
1. You said the truck had been leaking coolant for a while now. So, I would guess you are seeing a little on the driveway or other places you have parked the truck during this time. If not, then you might conclude that it is leaking internally into the motor (ie oil reservoir). So, were you seeing any pools of coolant under the truck? If not, then it sounds like a duck, is walking like a duck and must be a duck.

Oh, and the knock at start and oil pressure issues could mean there has been some damage done if indeed you have been running it with coolant mixed into the oil. I hope you get new oil and get it running but I would certainly get it checked out before running it much more. Did the knock seem to start around the time you noticed it using coolant? What about the oil pressure issues? Did those problems seem to go away right after the last oil change?
 
#4 ·
I assume the truck still doesn't start. :?: Does it turn over? Otherwise I'm at a loss as to what an oil change with tranny fluid will solve. If this engine will turn over enough, I'd suspect a compression test would be a good first order.
 
#5 ·
Update: Finished the oil change after digging out sludge from the oil pan plug hole.

It didn't want to crank, initially. It clicked a few times, but didn't seem to want to turn over (I believe I'm using the phrase correctly). I then noted that there seemed to be some electrical issue, as my dashboard lights were half-way blinking- rapidly dimming and going back to full brightness, and my door open ding sounded like it was faster than normal which I believe was it resetting over and over.

I jumped it with my wife's Focus, and after a few tries, it finally started! It was a little rough for a second, but the idle quickly calmed back down. I let it idle for 10 minutes, then cut it off for 6 or 7 before cranking it back up (without a jump; no engine fuss) and driving it around the parking lot. I'm wondering if I might have an electrical issue, too. Wahoo.

I noticed my coolant levels were again low. I do believe that I am somehow getting coolant inside of my engine, and that is the cause of the sludge. The popular answer would be the Castech cylinder casting as referenced above, which I'll further investigate later. But I may have an unrelated electrical issue. Either way, I got it to crank and that's progress.

I'm going to try to get it to a mechanic either tomorrow (with the help of a friend) or Monday (with the help of a coworker) and see if I can get some professional eyes on it. Again, I'll be sure to flood this thread with updates in hopes of it maybe being fruitful for someone else :)
 
#6 ·
I typed up a response to this at work but must not have submitted it. Oops. It's been a long day.

esox07 said:
1. You said the truck had been leaking coolant for a while now. So, I would guess you are seeing a little on the driveway or other places you have parked the truck during this time. If not, then you might conclude that it is leaking internally into the motor (ie oil reservoir). So, were you seeing any pools of coolant under the truck? If not, then it sounds like a duck, is walking like a duck and must be a duck.
I found no coolant on the ground, but I also park on a gravel portion of our yard, reserving the car port for my wife. That said, I've kept an eye open when backing out of other parking spots and haven't noticed anything.

esox07 said:
Oh, and the knock at start and oil pressure issues could mean there has been some damage done if indeed you have been running it with coolant mixed into the oil. I hope you get new oil and get it running but I would certainly get it checked out before running it much more. Did the knock seem to start around the time you noticed it using coolant? What about the oil pressure issues? Did those problems seem to go away right after the last oil change?
The knocking originated towards the end of summer, early fall. If memory serves me, I had an oil change shortly after, because I recall telling the mechanic that it was making a knocking sound and asked if he'd just take a general look at let me know if anything seemed off.

The first time I had over-heating issues was just a few months ago, and I don't believe I've had an oil change since then. I'm pretty sure I'm suffering from coolant leaking in to the cylinder(s). What fun I'm going to have ;)
 
#8 ·
I should have updated this forever ago. My apologies.

Short version: new crate engine. Wahoo /sarcasm

The rebuild was going to cost a few hundred short of a Jasper crate engine installation, so we opted for that route. I was reluctant to do it, because I could rebuild it (with the assistance of my mechanically-sound father) and replace the header myself, but I lacked a hoist and a slew of other tools.

At least the crate engine has a warranty :(
 
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