Aftermarket LS Oil pan?

[monzaaddict]

I was googling ls1 flywheels and see people recommending sealant on flywheel/flex plate to crank bolts to prevent oil leaks.

[n8thenetninja]

Per ARP's instructions, I used loctite on the threads, and ARP lube under the head for the flywheel/flex-plate bolts. Seems like they ought to know what they're talking about.
https://tech.arp-bolts.com/instructions/244-2901.pdf

I replaced the cam sensor this weekend, and there noted that there was oil on both sides of the o-ring. I haven't had a chance to get underneath and clean the oil off everything, so it's hard to tell if that stopped the leak or not. Guess time and the dipstick will tell.

[n8thenetninja]

Was going to race the car this Friday, but apparently the local county is on a power trip, and the local judge agrees that the county has absolute authoritarian power. As such, the race is probably canceled because the track doesn't have 2 weeks to submit a plan to counter COVID-19. The current regulation was submitted at 5pm Monday, and the track has to submit a "plan" 2 weeks ahead of time if there will be more than 175 people there. Good thing the benevolent government is looking out for us, or we would probably do all sorts of things that might keep their candidate from being elected. Or maybe we would just mind our own business and have a little fun. God forbid.

[n8thenetninja]

Well, the good news is I got to race this weekend! The bad news is I had to drive 3 hours one way to a different track (because the guvmint still has our local one shut down), and..... It's still leaking.

So, apparently it's not the cam sensor. *dramatic sigh...*

Not sure where to go from here. Considering taking it apart, installing a stock pan, then running it on jack stands for a while to see if it leaks. No idea when I'd have time for an experiment like that. Or there's always dropping the transmission to check the rear cover. Even more fun.

[AZ-520]

powerbyace has such a strange way of operation, I decided to break out the welder.

[n8thenetninja]

During Friday night races the leak got way worse. By half track it was dumping so much oil on the passenger header that the cloud of smoke almost obscured the car in a video someone took. I'm surprised the track didn't black flag me. I couldn't ignore it anymore after that, so I took it apart again.

This is the rear passenger side of the pan when a straight edge is held against the front


Here's the front when the straight edge is held against the rear


About as straight as a dog's hind leg.

Here you can see a melted spot where the header tube didn't clear the pan enough


I'm guessing that the pan had stress points built into it by the welding heat during modification, and then the header tube heat cycled it over and over, and the warping just got worse and worse. Not cool ACE. (so to speak)

I dug my old steel Hamburger pan out of the scrap pile, the one I mentioned earlier in this thread that I bashed in with a hammer to make it clear, and had a seam pop along the rear eventually... I welded up the popped seam, then banged on it until it was as flat as I could make it. I installed it with a new Felpro gasket and a bead of RTV, and after about 45 minutes of idling, it seems to be sealed up. I'll have to see how it does driving it, but on jack stands at least, this abused and repaired steel pan seals better than the pan I paid ACE $600 for. The one that never sealed right, and was further aggravated by the headers I paid ACE $780 for.

Seems I've paid ACE a lot of money for a lot of grief. $1380 between those two parts that are supposedly made to work with each other. Can't say I would recommend their work.

[BadBowtie]

Thats wild, I was thinking maybe you could get the mounting face milled if you know someone but thats a lot of material to remove.

[monzaaddict]

I (along with anyone following this thread/saga) can certainly understand your level of frustration with this. I don't think that the header could get hot enough to melt aluminum that far from exhaust port (maybe on an indy race car). I think the metal is just mushed from rubbing against the steel header. Were you able even to get to that one bolt where the header was rubbing the pan installed? It looks like oil was running out the bolt hole. The only option to fix that I think would be to grind rib down on pan and clearance header tube( or maybe use a torch to heat tube and bend it). As far as the warpage, I can only say how the guy who welded my pan dealt with it. Even with the pan clamped to his welding table, the front was warped up (actually down but pan was upside down while welding). All he did was place a piece of (I'm going to guess) 1/8 shim stock between pan rail and welding table towards back of pan just behind where warping began and re clamped pan to table. He ran a torch across pan (side to side) (You could see metal expanding and pan rail moving into alignment) and used clamps to bend warped part back flat. He had to repeat process as he moved towards front of pan. There was one area between where he had just used clamps to pull pan rail into position that was not flat. He again shimmed the rail on the sides of the warpage , heated the pan and used clamps to pull rail back into alignment. He let everything cool before removing clamps. It was not some big process. I don't think it took him an hour to weld and straighten pan. I will let you and ace hash out who should fix warpage. I explained the process to ace, I don't know why his welder isn't doing it. It just doesn't look good. On a positive note The welds that I can see on the pan look much better than some of the earlier ones.

[monzaaddict]

xxx

[monzaaddict]

I found these gm specs for pan installation . This is just for anyone following not necessarily you (nate). The torque specs are pretty low 18 ft/lb and 106 in/lb (about 9 ft/lb) for long bolts at rear. That is not much torque. I would guess you would have to over torque bolts to pull pan flat.

Important:
◦ The alignment of the structural oil pan is critical. The rear bolt hole locations
of the oil pan provide mounting points for the transmission housing. To
ensure the rigidity of the powertrain and correct transmission alignment, it is
important that the rear of the block and the rear of the oil pan are flush, or
even. The rear of the oil pan must NEVER protrude beyond the engine block
and transmission housing plane.
◦ Do not use the oil pan gasket again.
◦ It is not necessary to rivet the NEW gasket to the oil pan.
1. Apply a 5 mm (0.2 in) bead of sealant GM P/N 12378521 (Canadian P/N 88901148), or
equivalent, 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs
of the front cover gasket that protrude into the oil pan surface. Refer to Adhesives, Fluids,
Lubricants, and Sealers.
2. Apply a 5 mm (0.2 in) bead of sealant GM P/N 12378521 (Canadian P/N 88901148), or
equivalent, 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs
of the rear cover gasket that protrude into the oil pan surface.
Important: Ensure the oil gallery passages in the oil pan and engine block properly align
with the oil pan gasket.
3. Pre-assemble the oil pan gasket to the pan.
3.1. Install the gasket onto the oil pan.
3.2. Install the oil pan bolts (439, 453) to the pan and through the gasket.
4. Install the oil pan (400), gasket and bolts to the engine block.
5. Tighten bolts finger tight. Do not overtighten.6. Place a straight edge across the rear of the engine block and the rear of the oil pan at the
transmission housing mounting surfaces.
Notice: Refer to Fastener Notice.
7. Align the oil pan until the rear of engine block and rear of oil pan are flush or even.
Tighten
Tighten the oil pan-to-block and oil pan-to-front cover bolts to 25 ◦ (18 lb ft).
Tighten the oil pan-to-rear cover bolts to 12 ◦ (106 lb in).
8. Measure the oil pan-to-engine block alignment (a).
8.1. Place a straight edge across the rear of the engine block and rear of oil pan at the
transmission housing mounting surfaces.
Important: The rear of the oil pan must NEVER protrude beyond the engine block and
transmission housing mounting surfaces.
8.2. Insert a feeler gauge between the straight edge and the oil pan transmission housing
mounting surface, and inspect to ensure there is no greater than a 0.1 mm (0.004 in)
gap (a) between the pan and straight edge.
8.3. If the oil pan alignment is not within specifications, remove the oil pan and repeat the
above procedure.

[monzaaddict]

do you have the ace oil pickup tube? did you clearance windage tray. check how far pickup tube hangs below pan rail and then measure clearance inside pan with gasket to see if it is preventing pan from being tightened down fully.

[monzaaddict]

is the new (old) pan still not leaking?

[n8thenetninja]

The old steel pan has a very small drip. Not surprising considering how beat up it is. Nowhere near as bad as the ACE pan. I have a new problem now however...

When the car is driven for a few minutes, oil pressure gradually goes down and down, and pressure degreases with RPM. It got down to 10PSI by the time I got back home. After the engine was cooled off, pressure went back up to 40 at idle. The hamburger pickup tube has holes for 2 bolts instead of one, but I couldn't get the second one started because it hit the front cover. I figured maybe I used the wrong o-ring, and needed to add that second bolt. So I took the pan off again, used a different o-ring, and managed to get a shorter bolt in the second hole. Put it all back together the same way and waited until the next day so the RTV could cure. Still has the exact same problem. I still think the pickup tube is sucking in bubbles. This would explain why pressure would gradually decrease as the oil gets aerated, and why pressure would go down with RPM. This tube has a very short length after the mounting flange that goes into the pump, and the o-ring sits quite a bit closer to the flange than the other pickup tube. My guess is that it's just not getting the o-ring past the bevel in the pump. Or maybe there's a pinhole or a crack in the tube that I can't see.

To answer your questions, yes, I have the ACE pickup tube. It's too short to fit in the hamburger pan unfortunately. I did clearance the windage tray for the tube. I haven't measured the tube, but there aren't any witness marks on it that would indicate that the pan is touching it. My transmission bell housing doesn't have the lower bolts that go to the pan, so that also isn't coming into the equation.

I've considered taking the ACE pan to a machine shop to see if they can fix it. I'm getting a little hesitant to spend any more money on it though. I haven't talked to ACE yet, but I don't think I'd trust him to do anything other than send me a refund, and I doubt he'll do that. The welds do look better on this one than the first one he sent me. I would wonder if he sent me back the same one otherwise, since it leaks in the same place.

I think the best long term solution is probably to get a tubular k-member with a rack and pinion from Overkill Racecars. That's supposed to give you at least another inch to play with. That would allow me to fit an unmodified pan in there. That's expensive though, and I won't be able to do it right away. There's a possibility the headers won't fit too, which would be another expensive problem to solve.

The smartest thing to do might be to park it until I can afford better parts. Guess I'll call a couple machine shops and see what they say.

[n8thenetninja]

I called a trusted local machine shop, and he said he didn't think he could do it with his mill, but referred me to another guy who has a nicer machine. He really seems to know his stuff, and thinks he can mill it true and clearance the spot where the header is hitting. Price quote seems very reasonable if it works. I'll have to make sure the pickup tube still clears everything once it's done, but since the tube sits on the opposite side where the warping isn't as bad, I think it'll be fine.

Fingers crossed!

[monzaaddict]

I would go to a welder and have pan heated and straightened as I described then if still needed I would consider having flange milled. The way it is you are going to have to mill the flange too much to get it flat. Clearancing the sump can be done by you with a grinder. Header probably has to be clearanced too.