it will not shut off fuel pump due to oil pressure. The ecm grounds the fuel pump relay and IF sees that the engine is not running or has stalled will turn it off. As long as it sees rpm the ecm will keep the relay grounded. Has been that way on these engines since they came out.
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it will not shut off fuel pump due to oil pressure. The ecm grounds the fuel pump relay and IF sees that the engine is not running or has stalled will turn it off. As long as it sees rpm the ecm will keep the relay grounded. Has been that way on these engines since they came out.
I know you've kinda moved on from this thought, but here is a shot of how far my axle was moved forward. I don't recall the exact measurement either, but I'm pretty sure it was moved a full inch. I don't have a stock front bumper, and my front lower core support is already trimmed, but no clearance issues with the axle itself or my 37s. Bumpstops still function as designed.
The 5.3 I swapped into my Cherokee was from a '99 model year truck. The GM sender was removed and replaced by the sender for the aftermarket gauges I used. The PCM did not care, the engine started and ran fine.
bloc
SILVER Star
L92 Crate Motor w/Low Oil Pressure - LS1TECH
That's the one I had bookmarked, and no, they aren't specific about exactly what shut down. I know I saw another somewhere that I can't find now.. And quite a few of the engine being put into "limp mode" if oil pressure drops enough that the VVT doesn't respond as it's supposed to. That's another problem entirely.. and doesn't need a low oil pressure signal to happen, technically.
This all came from digging into how important it is to move that relief valve over.
Either way.. my plan is to leave the GM sender and drill/tap below it for the toyota sender.
I'm seeing stuff about a wire mesh filter below the GM sender clogging up and reporting false low oil pressure. I'm not sure how much flow there would be here without AFM.. I'll have a look at mine to see if the filter is even there on an engine with VVT but no AFM.
Thanks for the info. IMO an inch would definitely give the needed room for the LS3 pan, (important edit: IF the transmission mount is left in the stock location) for those interested in going that route.
That's the one I had bookmarked, and no, they aren't specific about exactly what shut down. I know I saw another somewhere that I can't find now.. And quite a few of the engine being put into "limp mode" if oil pressure drops enough that the VVT doesn't respond as it's supposed to. That's another problem entirely.. and doesn't need a low oil pressure signal to happen, technically.
This all came from digging into how important it is to move that relief valve over.
Either way.. my plan is to leave the GM sender and drill/tap below it for the toyota sender.
I'm seeing stuff about a wire mesh filter below the GM sender clogging up and reporting false low oil pressure. I'm not sure how much flow there would be here without AFM.. I'll have a look at mine to see if the filter is even there on an engine with VVT but no AFM.
Thanks for the info. IMO an inch would definitely give the needed room for the LS3 pan, (important edit: IF the transmission mount is left in the stock location) for those interested in going that route.
if worried, turn off the code w/ hptuners. I assume the gen IV has VATS just like the gen 3 motors...so you'll need to address that as well....mine runs w/o oil P, but throws a code. I'm just going to go to hardware store and get a tee to run both, but I'm not using the toyota sender either....
bloc
SILVER Star
GenIV does have VATS. Getting the BCM communicating with the ECM without VATS may present a challenge, but I'll document that when I get to it.
Does yours have VVT?
It did occur to me that the ECM may need to know oil pressure for proper VVT operation. and maybe for AFM if the engine has it (mine doesn't)
Does yours have VVT?
It did occur to me that the ECM may need to know oil pressure for proper VVT operation. and maybe for AFM if the engine has it (mine doesn't)
bloc
SILVER Star
I don't have a drill press so the hole ended up slightly offset, but it should work fine. The terribly-done scratch mark in the first pic is the extent to which the GM sender screws in to the post. Also this VVT but No-AFM/DOD engine does NOT have the small mesh filter in the sending unit post that clogs up on AFM/DOD engines.
In the process of assembling the engine with all new gaskets, water pump, PS pump, cleaning things up to the extent that is convenient, etc.
Mounts are burned on to the frame and painted.. I'm waiting for the 12.5mm drill bit so I can drill/tap the oil pan for the aux pressure relief valve before switching my engine-side mount legs with the stands so I can paint them. And no, I'm probably not going to go through a whole lot of effort to clean out the engine bay, at least beyond what's convenient when doing my wiring work. Damn thing will just get filthy again on my first trip. Plus I'm considering swapping the PS inner fender due to a rust spot around one of the airbox mounting holes. It's just a LOT of work to do that job.
It looks like I'm going to need to move the rear brake line that runs along the inside of the frame rail.. if I go rearward with the drivers side exhaust like I want a catalytic converter will be very close. Trying to decide whether I should move it now while everything is out, or wait and see if I can fit in a small heat shield.
Bloc
Which cats are you going to run?
Which cats are you going to run?
bloc
SILVER Star
Haven't even started thinking about it.
I have read that there is a huge spread in quality of the coatings and therefore longevity of the important parts.. so whatever I get it probably won't be the cheapest available. But I have a lot of research to do there and don't even know exactly how I'm going to route the exhaust yet. I don't live in a CARB state so that makes things a bit easier for me.
At this point the plan of attack is get the engine assembled and dropped in, shifter mods/wiring harness/PS&Transmission lines, exhaust, AC lines. Roughly in that order.
bloc
SILVER Star
Fxxx. Fxxxity fxxxing fxxx fxxx s***.
Since we all agree how great these LS engines are, I'd just like to point out toyota engineers wouldn't have been stupid enough to use an 8mm BOLT to hold on a truck exhaust manifold.
Now I have to pull the head. Since I'm doing that, I might pull both to have them cleaned up. Since I'm doing that, I might just rebuild the whole damn thing.
Couple scotches in and pretty annoyed right now. Obviously.
Tech: HEAT the head before removing exhaust manifold bolts on an LS. Maybe even try tightening them a degree before loosening. Anything to avoid this situation.
Since we all agree how great these LS engines are, I'd just like to point out toyota engineers wouldn't have been stupid enough to use an 8mm BOLT to hold on a truck exhaust manifold.
Now I have to pull the head. Since I'm doing that, I might pull both to have them cleaned up. Since I'm doing that, I might just rebuild the whole damn thing.
Couple scotches in and pretty annoyed right now. Obviously.
Tech: HEAT the head before removing exhaust manifold bolts on an LS. Maybe even try tightening them a degree before loosening. Anything to avoid this situation.
Same thing happened to me on 3 bolts, i was able to weld a bolt to one and get it out. The other 2 really got me good and i just ended up tapping the hole up the next size.
tractorpole
SILVER Star
I always have bad experiences with the small ez outs.
I have had good luck with the Snap-On Screw extractors like these
I have removed hundreds of 10-32 screws with stripped out torx with these and never had one break.
I recently bought a set of Irwin screw extractors from amazon but have yet to try them. They look to be the same quality as Snap-On.
Amazon.com: Irwin 53226 10 Piece 1/8-Inch to 13/32-Inch Hex Head Multi-Spline Screw and Bolt Extractor Assortment in Plastic Case: Home Improvement
bloc
SILVER Star
Any ideas on getting the broken extractor out?
drill a hole in a piece of steel then plug weld it to the extractor?
tractorpole
SILVER Star
You can use a left hand drill bit and go slow and hope you can knock it free. the extractors are really hard and will kill the drill bit if you go too fast and get the bit too hot.
Or you can try and break it with a punch.but that usually only works when there is an open space for the ez out to fall into.
bloc
SILVER Star
What I should have done:
I'll try the plug weld idea, then see if I can get the drilled bolt out with welding too. If not, go to a larger size. Though I have read that the cooling jackets are large and you risk knocking a hole in one.
Thanks for the ideas @steven17 @zoojp @tractorpole .. Already ordered that Irwin extractor set for next time.
I'm considering using toyota or VW stud and nut hardware for the manifolds to avoid problems in the future. bolts in this application are idiotic.
I'll try the plug weld idea, then see if I can get the drilled bolt out with welding too. If not, go to a larger size. Though I have read that the cooling jackets are large and you risk knocking a hole in one.
Thanks for the ideas @steven17 @zoojp @tractorpole .. Already ordered that Irwin extractor set for next time.
I'm considering using toyota or VW stud and nut hardware for the manifolds to avoid problems in the future. bolts in this application are idiotic.
I second the welding idea. I have taken quite a few of those 8mm bolts out that way. sometimes it takes a couple tries to get the nut to "stick"
i would use a 7/16 or 1/2 nut to give yourself enough room to get to the broken piece.
PS ford uses the same crappy 8mm bolts too
Good luck
i would use a 7/16 or 1/2 nut to give yourself enough room to get to the broken piece.
PS ford uses the same crappy 8mm bolts too
Good luck
FWIW, the ARP hardware for the LS exhaust manifold is of a higher quality material, and most likely won't break as easily.... Future removal
with these bolts the heads generally rust off. I used stainless studs on mine and figured it would save the aluminum too from running the bolts in and out. I've fixed a bunch of leaky manifolds on fords too with this problem. sometimes you get lucky and can actually unthread the broken piece by hand once the manifold is off.
bloc
SILVER Star
The ARP stud setup is very expensive. Granted.. I'd gladly pay that amount right now to not be dealing with that broken bolt/extractor.. but it wasn't much of an option from the junk yard.
Toyota's O2 sensor nuts and studs are the correct size to work.. but they will rust too. I kinda like VW's exhaust manifold nuts.. they are coated in copper and even the ones on my old jetta with 270k miles at the time spun right off almost like they were new. Also they were designed to thread into an aluminum head, unlike toyota's O2 hardware. Cost would be less than ARP bolt set by a little..
Toyota's O2 sensor nuts and studs are the correct size to work.. but they will rust too. I kinda like VW's exhaust manifold nuts.. they are coated in copper and even the ones on my old jetta with 270k miles at the time spun right off almost like they were new. Also they were designed to thread into an aluminum head, unlike toyota's O2 hardware. Cost would be less than ARP bolt set by a little..
