LB7: What to look for in used long block?

fl0w3n

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Jan 8, 2015
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Sorry if this isn't the best place for my question.

I'm going to look at/pickup a lb7 long block that came out of an 01 with 180k miles. The PO says it has a bad head gasket and once it overheated he shut it down and it sat. Then I guess at some point there was an electrical fire, so now he's parting it out. The motor has been sitting outside but under a tarp. Valve cover has been removed then put back finger tight for easy inspection.

My question is, this will be my first time buying a motor outside of the truck. What are some red flags to look for to potentially save myself from wasting money on a paperweight? I'll be trading for it, but he was asking $750 and I got him down to $6 before we settled on a trade. It comes with turbo, up/down pipes and manifolds, no electronics and I don't think any front accessories.

I figure I'll do head gaskets and studs, sac45s, throw the ProFab catalog at intake/exhaust, fpr, etc and then pull out my 340k motor and put this one in.
 

ikeG

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Apr 19, 2011
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Since you are planning on doing head gaskets, you will be able to see piston top condition and cylinder wall condition when you do that job.(Unfortunately you will own it regardless at this point). The only other thing that you could do is pull the lower oil pan off to see if any bearing etc material is laying in the bottom. But before you buy it, maybe someone/thing could hold it and you can turn the engine over with a breaker bar. If it is seized, its probably a project you dont want to get into. Unless you need the parts.
 

fl0w3n

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Jan 8, 2015
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Since you are planning on doing head gaskets, you will be able to see piston top condition and cylinder wall condition when you do that job.(Unfortunately you will own it regardless at this point). The only other thing that you could do is pull the lower oil pan off to see if any bearing etc material is laying in the bottom. But before you buy it, maybe someone/thing could hold it and you can turn the engine over with a breaker bar. If it is seized, its probably a project you dont want to get into. Unless you need the parts.

Good point, I wasn't planning on taking the pan off but easy enough while it's out just to be sure. That's what I'm most worried about with the 340k motor, and why I'm hesitant to do work on the top end.

Good idea on the turning it over, should I be concerned if it turns over too easily? or only if it feels seized?

I figure worst case is I can make a good motor out of the one in my truck and this one, and sell the rest off and get my $600 back.
 

fl0w3n

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Jan 8, 2015
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Another question, with a goal of 4-425 HP, should I still be looking at doing ARP head studs? Is there any gain in reliability over OEM, or is it mainly just better clamping force at higher power/boost?
I'm being semi budget minded here, but I like doing things right. My HP goal is based off two things, the clutch and not wanting to go more exotic to hold more power and secondly the use of the truck. It's going to be a solid axle adventure mobile on 37" tires, kind of jack of all trades type tow rig so big power isn't needed. I'll probably only run one tune that's a good all around configuration.
 

torqued2dmax

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Mar 26, 2017
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What is wrong with your eng ? LB7s are not known for head gaskets like LLYs are , if a gasket is blown the head way be cracked or warped the block may be cracked , if your eng is rebuildable at least you know what you have ! There is a good chance the other block has coolant inside doing bad things ! Good luck !
 

fl0w3n

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What is wrong with your eng ? LB7s are not known for head gaskets like LLYs are , if a gasket is blown the head way be cracked or warped the block may be cracked , if your eng is rebuildable at least you know what you have ! There is a good chance the other block has coolant inside doing bad things ! Good luck !

The lb7 in my truck has 340k and lived a hard life on a ranch/farm yanking goosenecks before I got it. It needs injectors, and I want to delete egr, do ProFab ybridge, up/down pipes, and manifolds. I figured it would be easier to just pull the motor and do all the work at once. I'm going to send in an oil analysis to gauge bottom end health but I am worried about its life as I get up to 400k and above miles.

I figured if I needed to I could use the good heads off my current motor on the one with bad head gasket if I needed. If the block is bad then I guess I'd be back to square one.

Maybe I'm better off pulling my current motor and doing some investigation and rering/bearing it. But that's going to take much longer than having a second motor ready to plop in.
 

Dozerboy

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Jun 23, 2009
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I think your taking a big chance on this new engine. Unless you think you can get your money back it the thing is a paper weight.


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Awenta

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Sep 28, 2014
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Just get the transmission built and put a tune in your truck. When something happens worry about it then. I don’t think it’s any riskier than the engine you’re looking at. You don’t need to do anything to it to get 425hp.


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snowman22

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Jan 30, 2018
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Unless you can get your money back, I wouldn't be touching that motor with a ten foot pole. If any coolant got into a cylinder and sat, it's game over, or a start to a big nice build..

Just put a set of good injectors in your truck and get a mild tune. It will run great and should last a long time. My LB7 rolled 350k before I sold it, and it was abused for over 100k and still ran great.

I don't know much about the manuals and the clutch holding power, but I would change it if it's in the budget. Mainly because you are trying to turn such large tires.
 

fl0w3n

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I do plan on doing the clutch once it goes, and I was thinking the single disk southbend which is good for 425hp/800tq hence my relatively low power goal. I'd need to step up to a dual disk for more power than that.

So it seems like the consensus is leaning towards not risking it with the CL bad head gasket motor.

Sounds like no one seems to be batting an eye at just throwing some sac 45s into my 340k motor and a small tune and running it? I guess that's good, saves me time and money.

For what it's worth, I just got this truck so I don't know much of its history other than what I've already stated. All I've done is put a new FPR in to fix the lopey idle, which it did, but still shakes like a mofo likely from the injectors. I've hardly driven it since buying it.
 

fl0w3n

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Profab manifolds and uppipes are not needed for 400hp. Save that loot for the repairs

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Definitely not needed, I'm only doing that for the sound really, and since it's a Cali lb7 to get rid of the egr riser, and just sleep tight at night knowing :coolspot:


I'm aware the power level I'm talking about is a drop in the bucket, that's not my concern of how to make it. I just want to build a reliable adventure truck out of this thing.

From the feedback I'm getting I think I'm just going to leave my motor in the truck, throw injectors and whatever else I want at it, run it, and if I get some rod knock or blow by later I'll worry about it at that time. Certainly saves me a lot of time and money.
 
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torqued2dmax

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I live 5mi from I80 so when I go to fuel up I look to see if there any duramaxes there and I ask about how many miles they have , many of the Lb7s , LLYs and LBZs have over 500,000 , and today the guy said here look inside and see for yourself 665,000 , the valve covers have never taken off ! If you have good oil pressure and good compression just make sure the you install good quality injectors , like from Lincoln , make sure all High pressure lines are cleaned , lift pump with duel filters , mild trans safe tune , good to go !
 

fl0w3n

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Jan 8, 2015
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I live 5mi from I80 so when I go to fuel up I look to see if there any duramaxes there and I ask about how many miles they have , many of the Lb7s , LLYs and LBZs have over 500,000 , and today the guy said here look inside and see for yourself 665,000 , the valve covers have never taken off ! If you have good oil pressure and good compression just make sure the you install good quality injectors , like from Lincoln , make sure all High pressure lines are cleaned , lift pump with duel filters , mild trans safe tune , good to go !

That's good to hear! Maybe I'm just thinking into it way more than I should be.

I'm doing Lincolns SAC 45 injectors because of the different needle/seat design, hoping those are more reliable than Bosch remans in the long run, and because of the warranty. I'll do all new HP lines, probably redo low pressure lines from the tank forward eventually since I'll be going to a larger tank and need to drop it for the lift pump anyways.

Thanks everyone for chiming in
 

torqued2dmax

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Mar 26, 2017
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Brookville, PA
Good choices and dont forget to check out the injector return lines they are known to leak , I forgot to mention them before ! You dont want to go through all this then spin a bearing because of fuel in pan ! Good luck !
 

fl0w3n

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Jan 8, 2015
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Good choices and dont forget to check out the injector return lines they are known to leak , I forgot to mention them before ! You dont want to go through all this then spin a bearing because of fuel in pan ! Good luck !

Certainly not. When I bought the truck I checked oil for signs of fuel and didn't see any, so I'm hoping I'm good on the bearings.
 

2004LB7

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Dec 15, 2010
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I second what everyone else is saying. Sac 45 injectors, a mild tune and clutch if you want. Enjoy

I would be more worried about the rest of your truck with rust, wheel bearings, etc then the milage on the engine. Since you know the history and condition of your truck just and are happy with it, there is no reason for another engine and its expenses

With new injectors and maybe a CP3 you will be surprised how good it can run at that milage
 

fl0w3n

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Jan 8, 2015
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I second what everyone else is saying. Sac 45 injectors, a mild tune and clutch if you want. Enjoy

I would be more worried about the rest of your truck with rust, wheel bearings, etc then the milage on the engine. Since you know the history and condition of your truck just and are happy with it, there is no reason for another engine and its expenses

With new injectors and maybe a CP3 you will be surprised how good it can run at that milage

It certainly makes me feel more comfortable that this has been everyone's response. I'll look into testing the CP3, or just budget for replacement. Thanks for the heads up. The turbo is the other thing I was a little worried about with the mileage.

I plan to put a rebuilt Dana 60 in the front, rebuild the 14b in the rear, swap to a 205 transfer case and rebuild driveshafts. That'll take care of the drivetrain, along with the clutch.

The interior I already picked up a full set of front/rear seats, I'm still debating putting new rubber floor in or switch to carpet, with sound deadening under. Replace the steering wheel and add in my stereo, maybe a headliner eventually and the thing will be practically restored mechanically. Crank windows and manual locks, manual seats, nothing to go wrong there.
It's a California truck so there's no significant rust to speak of. Small chip on the hood, but I may swap to the 03+ grill and change the hood eventually.
Maybe add some new cab/body mounts to that list.

I got the truck for $5k, which isn't a steal but it's not bad either IMO. I figure I'm going to put another $10k into it over time, and for $15k I'll have exactly what I want and good for another 150k miles VS 10-15k for a lower mile truck and then having to add in everything I want still for another 7-8k at least
 

clrussell

pro-procrastinator
Sep 23, 2013
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Do not use the single disc. Pony up and buy the street 650 dual disc. The single won't hold a 100hp tune.. I know