CK5
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2000 Buick Sleeper build - 2nd engine trashed!

Tore into the engine and the whole top end looks perfect. Pulled a couple of rod caps and the crank looks good. Bearings just look old.

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The oil pump is trashed, though:

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There were lots of bits of metal in the oil filter, but hardly anything like that in the pan, so the pump may have been the whole problem. I just don't see what would set this off. I've done several oil changes on this and never noticed anything before. The oil pickup screen is intact and not plugged, so where does a foreign object come from?
 
Here's the next victim:

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The returnless fuel system and electronic throttle will be discarded. This blower (Gen V) is more efficient than the pre-2004 models (Gen III), but I probably won't get the new adapter plate, pulley and do the additional mods to run it. My older blower is already modified to match the cadillac throttle and the outlet modified similar to this one, so it wouldn't be as much of an upgrade anyway. I'll probably just sell it as some people think they're bees knees.
 
You put an Eaton M90 on a 4.0L? You'll have to fill us in on the intake manifold, injectors, tuning, etc.


Everything is progressing with the new motor build, except for 1 missing part! To use the LS6 springs, a modified retainer is required and I can only get them from ZZP (or get a stock LS6 retainer and take it a machinist). Well one spring slipped off the compressor tool and launched the retainer to the dark recesses of nowhere. If I can't find it I'll have to finish up with one stock spring and drop the engine in with the front valve cover free and get a replacement on Tuesday.
 
This front cover and oil pump from the "new" motor look good, so they'll stay (looks like I have 4 to choose from!). I just left the water pump in it.

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Here's my obligatory timing picture. This is so I don't go back to wondering if I had it right or not. Blue Fel-Pro gasket going on the front cover.

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So the engine went in the car with one rocker arm missing and nothing installed that blocks removal of the front valve cover. Since headers can only be installed after the engine is in and I left the A/C, power steering and intercooler all unopened hanging in the engine bay, there's a lot of stuff to work on even without the missing retainer.

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The process of swapping the valvetrain between engines, the intercooler gaskets, etc. made me realize how much more work this is than swapping a stock motor. That whole project could have been done in a day, I think.
 
The new motor is actually an L67 (Gen II S/C) with an L32 (Gen III S/C) intake manifold and supercharger on it. It looks like it was done recently as all the gaskets up top looked new. The valve cover gaskets are blue, which I've never seen before: just GM orange (which leak) and ZZP black (which harden and then leak). The weird thing about this engine is how dry it was. There was dust all around the front main seal, mud on the front of the block and rust forming on the rear head. After pulling the last motor, I'm convinced 90% of the oil leak was from the rear valve cover. Since these blue gaskets were in very good shape and very soft feeling, I cleaned them thoroughly and put them in.
 
Fel-Pro are usually blue. They claim to make the "improved " gasket set for the 3.8/3.1 motors.
 
I ended up driving 30 miles to ZZP for a set of modified valve spring retainers since they won't sell me just one. I'd hoped that part would show up as I put more stuff back together and cleaned up parts. Maybe it still will. I suspect that a stock LS6 retainer could work just be grinding down the bottom. I had believed that the inside diameter was modified to accept 3800 locks since the original set I bought had that feature wrong on 1 out of 12 parts. Looks like the locks are the same. The LS6 retainer is used because it gives a little more spring height than the 3800 retainer, but apparently it hits the valve guide seal (without the machining).

I'm still not done with this. S/C is mounted, fuel lines and vacuum lines on, all accessories mounted. Need starter motor, oil filter, belts, fluids and a few odds and ends.

Then I can get back to getting the K5 ready for dune fest.
 
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But my engine is trashed now. I guess I was running some kind of glitter oil :doah:. The "Change Engine" light came on yesterday (the one that looks like a genie lamp). I tested the oil pressure switch and it triggers around 5psi :eek1:. Tested the pressure to vary from 10-20psi in the garage. So it's chicken and egg whether low pressure killed the bearings or damaged bearings lowered the pressure. It could be the 6500RPM WOT shift I did last week destroying a Duramax who thought he was hot.

This design is stupid:
  1. No oil pressure gauge, even though that's the life or death of your engine
  2. The oil pressure warning triggers way too low (it's too late)
  3. The logic on the switch is backwards, such that unplugging it, cutting the wire or a failed switch keeps the lamp off.
Was never low on oil, never ran hot, never made any noise. All I have to do is put in fresh oil, unplug the pressure switch and post on Craigslist! :ignore:

Sort of want to just move onto some super simple MPG machine, but I know I would miss the torque. Makes sense to fix it either way since you can't get much for a non-runner.

This post reminded me of an issue I ran into recently. A few months ago I guided my brother through a lower-end rebuild on a stock 3800 for his 2004 Buick. He did all the work himself and seems slightly hooked on mechanical things now. Maybe I should have done that 15 years ago. :haha:

Neither of us could make any sense of the backwards bell housing bolt. Total headache to get to, even in his relatively spacious engine compartment. :doah:

The oil pan caved in on a pothole, and he didn't see oil leaking, so he continued to drive until loss-of-power set in. Scored the crankshaft and its bearings, and the oil light never came on. :angry1:

Last week the light flashed on and he freaked out, pulled off the road, and immediately checked the oil level. I guess he's learned his lesson. :wink1:

Any ideas what would cause a scare like that? No abnormalities were noted under the hood, and the light was only on for a few seconds. But both of us were uncomfortable with the "replace engine" light coming on at all.
 
Whatever happened to the Pontiac at the beginning?
That was a '97 GTP that I bought with 34,000 miles on it and sold with like 212,000. Great car. Brought all of my kids home in when they were born. It just had enough Michigan winters on it that I was ready to move on. I had replaced the rocker panels and repaired the rear strut towers and also did some bodywork over the years but you always lose the battle eventually.

That one was just bolt-ons. A cold air intake, a 3" downpipe, 2.5" cat-back, slightly larger throttle body, off-the-shelf tune and 3.4" pulley. Probably shouldn't have run that pulley without headers, but it went like 150k like that and still ran well. It was also lowered and had the cop car sway bars.

This post reminded me of an issue I ran into recently. A few months ago I guided my brother through a lower-end rebuild on a stock 3800 for his 2004 Buick. He did all the work himself and seems slightly hooked on mechanical things now. Maybe I should have done that 15 years ago. :haha:

Neither of us could make any sense of the backwards bell housing bolt. Total headache to get to, even in his relatively spacious engine compartment. :doah:

The oil pan caved in on a pothole, and he didn't see oil leaking, so he continued to drive until loss-of-power set in. Scored the crankshaft and its bearings, and the oil light never came on. :angry1:

Last week the light flashed on and he freaked out, pulled off the road, and immediately checked the oil level. I guess he's learned his lesson. :wink1:

Any ideas what would cause a scare like that? No abnormalities were noted under the hood, and the light was only on for a few seconds. But both of us were uncomfortable with the "replace engine" light coming on at all.
That bolt is affectionately called the "B***h Bolt" on W-body forums. I remember getting it out with like 4 extensions and 2 U-joints or something but you only have to do it once. They never seem to get reinstalled :grin:, which is fine as long as you keep the tranny-to-motor brace at the far end, but I've seen those deleted before as well :what:. You rebuilt the bottom end and it lived for a while? The oil light will fail to come on if a) the sensor is unplugged, b) a wire is broken or c) the sensor is bad. If it was driven to the point of power loss the bearings must have been damaged and it seems like only a matter of time until the clearances open up enough for oil pressure to drop.

What shop was this?
I just searched my email and it looks like it was a Craigslist ad, but I don't see anything like that on there now.
 
Started the car up tonight to see 60psi of oil pressure and a nice idle. Only ran it a few minutes and didn't search for any problems because I would rather find them another day...
 
That bolt is affectionately called the "B***h Bolt" on W-body forums. I remember getting it out with like 4 extensions and 2 U-joints or something but you only have to do it once. They never seem to get reinstalled :grin:, which is fine as long as you keep the tranny-to-motor brace at the far end, but I've seen those deleted before as well :what:. You rebuilt the bottom end and it lived for a while? The oil light will fail to come on if a) the sensor is unplugged, b) a wire is broken or c) the sensor is bad. If it was driven to the point of power loss the bearings must have been damaged and it seems like only a matter of time until the clearances open up enough for oil pressure to drop.

I think he wound up reinstalling that bolt, but I know he strongly considered chucking it. I helped for the removal phase, and we did what you suggested, stacking extensions until the ratchet was over in the opposite wheel well.

He removed every internal moving part and checked all the bearing surfaces. Ended up replacing bearings and the crankshaft, the oscillating parts all looked fine. Then the engine was thoroughly flushed of all the glitter, and he put it all back together. This was at Christmas time, he now has 1/2 a year's worth of driving around the country on it (maybe 15,000 miles?). Not enough to qualify as longevity yet.

If the bearings are all new, why would they be opening up clearances? :dunno:
 
I was saying that the old bearings would open up. I guess you're saying it was rebuilt soon after the low oil incident and the oil pressure light came on with the rebuilt motor. Only reason I can think of is something plugged the oil pickup or it has a FRAM (assuming the motor is fine).

15k is still way over what people say you get from replacing bearings on a 3800 bottom end. Even machine shops that resurface and resize everything are reported to have fairly low longevity.
 
I was saying that the old bearings would open up. I guess you're saying it was rebuilt soon after the low oil incident and the oil pressure light came on with the rebuilt motor. Only reason I can think of is something plugged the oil pickup or it has a FRAM (assuming the motor is fine).

15k is still way over what people say you get from replacing bearings on a 3800 bottom end. Even machine shops that resurface and resize everything are reported to have fairly low longevity.

Yes, the car was pushed into the shop immediately after the low oil incident. The light incident was recently, and the large amount of work required to replace the lower end bearings is why he was freaking out. He doesn't wanna do that again.

As for the longevity...yikes. I'm pretty sure nobody told him that, or he probably would have chickened out on the whole thing. I guess we'll just keep watching to see how well it ages. :dunno:
 
Well I drove the car around tonight. Other than finally getting enough coolant in it, it was freakishly uneventful. No signs of oil leaks, coolant leaks or vacuum leaks - what's going on?

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I did see a code pop up for something with TPS, but the signal from TPS seems fine. I'm sure if it's a real problem it will present itself more over the days and weeks to come (as I actually drive it!).
 
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