Lpop or bad pickup tube?

Steve's red stroker · Sep 24, 2012

I just picked up a 02, I changed the oil right away, realized that it was overfilled a bit (1gal.) filled it to the full mark and it wouldn't start, had to add 3qts to get it to start. The resivior seems to drain down overnight, as it starts up right away runs for a couple seconds then dies, and takes a few seconds to start back up. Once its running it runs fine, unless you go over half throttle, icp peaks around 2300psi then falls to around 1200 at wot. I already have another pickup tube and gaskets and ordered a melling m208 lpop. Any ideas besides this? Don't really want to pull the motor, but think I need to, any help or ideas would be great!

TARM · Sep 25, 2012

Was this thing running when you got it or was this the first time you started it?

Did you keep the extra 3 quarts of oil in it the whole time after you added it?

It could be that while you drained the oil all the oil drained out of the HPOP and then your cranking slowing brought it up and the startup just happened to come at the same time with the adding extra oil. When you say the Res drained over night were you sure to check it before and it was actually full and then it was empty the next morning or did you just check it in the morning when it would not start and found it empty? The point being it may have been mostly empty when you shut it down. Point is a PU tube issue would not cause a HPOP res to drain but it could keep it from filling up or refilling.

Try putting oil in thru the port or the oil pressure sensor port on the top of the res and then check it in a few hours and see if the level has dropped more so the level is more than a inch below the top.

How did the oil look in the res or on the dip stick after running it. Was it foamy?

See if with the res filled and the oil at the proper filled level not over filled will it stay running. If its does not then again try it doing the oil PU tube test. (Over fill by 3 quarts and jack up the rear or having it sitting nose down hill or off a curb.) If it starts and runs I would think you have a PU tube issue.

If it does end up being the PU tube you have to pull the engine to replace it. I would think long and hard the plans you have for this truck and do ANY AND ALL you can while its out.

But before you do any work at all after the testing I would if you have not already run a compression test on all the cylinders. No reason to do any work at all on this engine if its got bad compression. Need to then decide if you would do better picking up used engine or doing a rebuild. If compression is fairly consistent for all cylinders and around 400 psi you know its worth putting some time into.

Things to consider:

if its up there in miles close to 200K I would pull the injectors if they are original send them off to be rebuilt or swap them for some stage Is. At the very least replace all the orings.

Replacing the LPOP check the front cover where the LPOP mates. If there is scoring at all swap out for a cover thats in good shape.

Its an 02 so its got PMR rods. If you plan to add any real power upgrades think about swapping rods to stock forged rods while its out.

Replace the oil dipstick connector as they tend to be a point of oil leaks as these age.

The pan itself. If its in bad condition (rust) replace it.

Valve springs they have shown to get quite weak after a 100K. COmp Camps 910 are cheap. Add in a set of shims to bring them into spec would be a good move.

Turbo up pipes. If they should any leaks etc replace while the engine is out is so much easier.

If you plan for head studs now is the time. Same goes for a fuel system. You can get to those lower back inspection ports real easy with it out.

Do a bit of reading on sealing the oil pan. Make sure not to get the bolt holes full of sealant as its been said the hydraulics from tightening down the bolt compressing the sealant can crack the block down there.

For me I would do that compression test first as you need the starter to do it easily. See if the engine is worth the work then go from there.

Steve's red stroker · Sep 25, 2012

Thanks for the great info I'm going to look into into more this weekend

JLDickmon · Sep 29, 2012

Great post, TARM

TARM · Sep 29, 2012

Just hate to see guys go to all the work of doing something and leave a bunch of things undone when they had that perfect opportunity to do them when everything was tore apart.

I had to pull some injectors mad was changing out my harmonic balancer. Since I had everything off for the VC and the fan and shroud for the balancer I looked at what upgrades I had stuff for waiting to go on.

I replaced the LPOP with a Melling cost $49. Since the front was open figures now was a good time to install a IH water pump with built in bypass filter and cut off. A member had purchased an IH pump but it did not work with his Dual alt kit so we just swapped as my pump was only about 500miles on it. $20 for shipped etc..

Had a Hypermax IC as part of a parts swap deal. Installed that. HAd a 6.0 trans cooler. Installed that. Upgraded the PS cooler to the old stock trans cooler for better cooling with big tires. Pick up a V10 cooler from a ambulance in a salvage yard for $15 mounted it in the bumper to act a fuel cooler spliced into the tank return hose.

Picked up some OTR truck radiator hose 3" Cut it to replace the soft silicon stock boots on the turbo system.

Since I had the grill off I figured now as a great time to install some driving lights in the header panel. Using Advanced Autos online discounts I pickup a set of Hella 700FF for $60.

This allowed me to get a ton of things done all having everything torn apart once.

Sure I will be digging back into things in the future without a doubt but I try to get the most out it everytime.

One of the biggest things is anytime things are apart take the opportunity to degrease, clean scrub etc.. Over the years the more I work the more I appreciate a clean work are and engine bay and parts. Its easier to find leaks and other issues. It makes you more detail oriented. It doesn't seem to be a big deal to half@ss or rig something on a dirty greasy engine but on a clean well kept one it seems wrong. Always look for ways to improve something while you are there. From changing out a crapping worm clamp for a tbolt or a basic hose and fitting for a PL SS hose with its JIC fittings. Add wire loom and wrap when you see exposed wires etc.. Wrap IC pipe, AC lines, Up pipes

I am just slowly starting to do these things on this 7.3 engine. It will likley take a year or so to get all done as I do it when I am in there.

TyCorr · Oct 6, 2012

My motor is a greaseball Tim! I'm chasing an oil leak however and narrowed it.down to the hpop. Got an srp1.1 on the way and a comp fuel system with bowl delete. I'd love to get the grease knocked down, eliminate leaks, and then keep it all clean. I was going to pull mine but I'll just rebuild another with billet rods and paint that up.

Oh and I need to decide what nozzles I want to run on my 275s.

TARM · Oct 7, 2012

200% unless you need for some reason to just be super tame with not even the smallest compromises. IMO 200% are the perfect do everything nozzle size. Turn it up to the max it can flow on a worked over set of hybrids and they can make stupid levels of power. Turn them down and they offer a great tow range. One or two tweaks at most if the tuner has experience with them and they will idle as good at as any single shot injector.

A very good match to that would be a turbo like the 4294 or one with a profile spec similar. I like garrett turbos if you are not going to need to be making wheel changes etc.

TyCorr · Oct 7, 2012

TARM said:
200% unless you need for some reason to just be super tame with not even the smallest compromises. IMO 200% are the perfect do everything nozzle size. Turn it up to the max it can flow on a worked over set of hybrids and they can make stupid levels of power. Turn them down and they offer a great tow range. One or two tweaks at most if the tuner has experience with them and they will idle as good at as any single shot injector.

A very good match to that would be a turbo like the 4294 or one with a profile spec similar. I like garrett turbos if you are not going to need to be making wheel changes etc.

I'm leaning towards them. I'm honestly only looking for 450-500 for now and it'll only see that occasionally. As for air, I'm shopping for a gt55 series to feed the 38r. The tried and true gt4718 and 38r combo would work but the former would work better especially if I decide to go to a 300 over edm nozzle.

TARM · Oct 7, 2012

Yes even at those power levels what I like about the 200% is its always possible to get whatever HP peak at a significantly lower TQ level than you would with the next smaller nozzles. Back when people were first getting 500 on 100% TQ levels were close to 1200 as RPMs peaks were so low. Now they are higher but with the 200% is that much better? 2600 HP peak vs 3200. Then based on the tune your tuner can bring the TQ up however you want. Example: a DD have it curve up gradually to the peak so you get the least amount of CP under the curve. Tow tune it jumps up early and flat lines. etc.....

TyCorr · Oct 7, 2012

TARM said:
Yes even at those power levels what I like about the 200% is its always possible to get whatever HP peak at a significantly lower TQ level than you would with the next smaller nozzles. Back when people were first getting 500 on 100% TQ levels were close to 1200 as RPMs peaks were so low. Now they are higher but with the 200% is that much better? 2600 HP peak vs 3200. Then based on the tune your tuner can bring the TQ up however you want. Example: a DD have it curve up gradually to the peak so you get the least amount of CP under the curve. Tow tune it jumps up early and flat lines. etc.....

I'm not sure about the difference between StgIIs and a hybrid but the 80% nozzles were better on them. The 100s idled crappier(lopey or missed) and the egts were hotter. I made about 20hp more on the 100s vs the 80's keeping smoke where I wanted it. That whole scene, the 175cc inj, feels like pushing something to the ragged edge. Need duals to keep em happy in oil. I'm hoping the hybrids are a whole new world for me, lol. I like the peak power potential but I'm hoping they do everything else better too.

I'll have Matt R tune it all. For sure! I've been dying to try him out.

TARM · Oct 7, 2012

You should be happy. Matt has done a good number of 200% these days and his over all tuning strategies IMO are better especially for DD or trucks used on the street. IMO a street truck that a person drives somewhat hard takes far more abuse than anything used on the drag strip. Just thinking of how many times while driving a person might nail the throttle thru the gears vs how often you go down the track doing basically the same thing. Then add in all the rest of the hours driving etc. So IMO a DD tunes are that much more critical to have dialed in properly.

For a given nozzle size the difference in HPOP oil needed for the same vol of fuel injected is roughly 30%, Hybrid vs A code (stage I/II).

With that said there is no question that you need a upgraded HPOP such as a SRP1.1 to get ideal performance from 200% but then you need the same for 80%-100% in a A code so.......