Chevy Impala SS Forum banner

1 - 20 of 21 Posts

·
Registered
Joined
·
29 Posts
Discussion Starter #1
Wassup 2 Gang, I’ve finally got a chance to find another used LT1 motor for decent price with complete wiring harness. For My 94” that hasn’t been the same since my last post of overheating. It’s starts and runs sounds weak starting up. This newer motor It was in a 1995 Chevy Caprice 5.7L believe to come from police auction. I knew the guy that had sold out to this yard he had about 20 B-bodies in storage.

Has 107K miles believe to have sat for a while was in the vehicle before been dropped off I have little time at shop before I actually install.What should I replace without getting to deep into a rebuild? I’m not to happy of the rust on outside block.

Was told passed Compression Test was done by yard.Everything seems stock. Coolant that leaked from hoses looked at bit old dirty a darkish green color seemed a little odd. Plan On Changing Oil Pan,Gasket.WaterPump,T-Stat.Spark Plugs,Wires,EGR, possibility Harmonic Balancer and Oil pressure switch.


192582

192583
192584
192585
192586
 

·
Registered
Joined
·
8,487 Posts
Now is the time to clean/paint the block before install. Junkyard motors can be a crap shoot but if there is some form of documentation (read did they write down compression test # or just say "its good") on the compression test. 107k mi is not much so it should be indecent shape.

The SEO green hoses suggest it came from a 9C1 car.

I would pull the WP and Opti and replace front seals for both. If it has original AC Delco Opti keep it but open it up to confirm no crap is inside it. Maybe a new C&R if it does have 107k on opti. Use loc-tite on rotor screws and skim coat of dialectic grease on cap large O ring

Might want to replace seals on cross over pipe while engine is out. May likely need PB on those banjo bolts to get them off. New plugs & wires. change oil and fire it up
 

·
Registered
Joined
·
1,596 Posts
In addition to everything you just mentioned, while the engine is still out of the car …
You may want to replace the coolant crossover tube in back of the heads. The one pictured looks rusty, and I don't know what the one in your car now looks like. If both look bad, you can use a B-car, F-car, or Y-car crossover, so buy whichever you like.

If you're concerned with surface rust, think about the inside of the engine. The knock sensors / freeze plugs will be easier to remove (or replace), which will let whatever old coolant is still in it to escape even more easily.

Can't remember the TSB number, but I could swear that those little bars on the exhaust manifolds were supposed to be cut off. Probably a good time to upgrade the gaskets and exhaust bolts too.

In the mood to block off the EGR - or just plain delete it (depending on emissions regs where you live)?

Even if you are forced to keep the AIRpump, you can still block it off internally. Otherwise you can sell it to some poor sap who's stuck needing one.
 

·
Registered
Joined
·
8,053 Posts
BALLSS: Might want to replace seals on cross over pipe while engine is out.
Marky-: You may want to replace the coolant crossover tube in back of the heads.

Richa Racha Fracka Dadburnit - beat me to it. First thing I spied, and no better time to attend to it. And all the ex. man. bolts too as mentioned. PS wiring looks "OK", but no DS pic. Get a metal cap on No. 7 wire, make certain the mtl. keeper is intact (including properly trained wire inside, PLUS all the proper looming on that side.


Dae1: "It’s starts and runs sounds weak starting up."

OP, it's funny as these cars age we're hearing morn-more about collateral damage from one thing affecting performance of other old parts. If'n ya ain't yanked that motor yet, maybe consider the difference a new starter and/or IC/ICM might have on that "weak starting" after the overheating episode. OTOH you probably don't want the answer Hahaha
 

·
Registered
Joined
·
11,047 Posts
Make sure you do any mods required for the 95 to 94 transplant.
 

·
Registered
Joined
·
29 Posts
Discussion Starter #7
So far she doesn’t look to bad pulled Oil Pan, valve covers and Oil filter adapter. Oil looks fine just darkish color no signs of Coolant or metallic flakes.

Plan on removing Waterpump and maybe distributor don’t like to use aftermarket distributor. So would like to reuse after replacing Main Seal.

What’s the order of gaskets for oil filter adapter. Did repair before on motor that’s currently in caprice and would leak still after repair.

192597

192598

192599
 

Attachments

·
Registered
Joined
·
386 Posts
Oil filter adapter-scrape out the black gasket in the center, use the round o-ring in the groove, the rectangular o-ring is too fat. Fel-Pro gaskets.

Ken
 

·
Registered
Joined
·
8,053 Posts
The oem 'gasket' is metallic based. It will either spall & pop right out, or take a hour to grind and chisel. Anticipate the latter. I think I heard current design is different composition = leaks less.

192609
 

·
Registered
Joined
·
8,053 Posts
Doubled post
 

·
Registered
Joined
·
29 Posts
Discussion Starter #11
Now is the time to clean/paint the block before install. Junkyard motors can be a crap shoot but if there is some form of documentation (read did they write down compression test # or just say "its good") on the compression test. 107k mi is not much so it should be indecent shape.

The SEO green hoses suggest it came from a 9C1 car.

I would pull the WP and Opti and replace front seals for both. If it has original AC Delco Opti keep it but open it up to confirm no crap is inside it. Maybe a new C&R if it does have 107k on opti. Use loc-tite on rotor screws and skim coat of dialectic grease on cap large O ring

Might want to replace seals on cross over pipe while engine is out. May likely need PB on those banjo bolts to get them off. New plugs & wires. change oil and fire it up
They never showed actual number of compression test. I just went off faith & words turned engine by hand before tearing down.

Has the yellow cap Opti distributor. Which is AC Delco correct? You suggested new cap and rotor should I use one from O’Reillys Spectra Premium brand?
 

·
Registered
1996 ImpalaSS WX3
Joined
·
371 Posts
Wassup 2 Gang, I’ve finally got a chance to find another used LT1 motor

Has 107K miles believe to have sat for a while was in the vehicle before been dropped off I have little time at shop before I actually install.What should I replace without getting to deep into a rebuild? I’m not to happy of the rust on outside the block.
Actually I remember my auto shop teacher in high school who did some racing, telling us he preferred to build engines from blocks that had been exposed to the weather and showed signs of age and rust on them.
The rust sand/bead blasts right off, and the time as it passes, exposes it to the different temps and conditions of being outdoors in the weather, which he claimed hardened and stiffened the block, making for a more durable racing engine.
I do know the older the steel is, the better the steel is.
The highest carbon steels were produced during the 1940’s and before due to the different processes and methods used at that time.
Enough history, as long as there’s no internal rust, you shouldn’t need a complete rebuild.
But don’t be afraid of the weathering.
 

·
Registered
1996 ImpalaSS WX3
Joined
·
371 Posts
The 94 - 95 differences pcm wise can be dealt with if they don’t already swap with no mods necessary, but since Marky is already here.
He can be a huge help when it comes to any of the tuning or difficulties you may encounter between the two engines performance wise.
He’s helped a lot of folks with exactly these types of situations.
 

·
Registered
1996 ImpalaSS WX3
Joined
·
371 Posts
You may want to replace the coolant crossover tube in back of the heads. Can't remember the TSB number, but I could swear that those little bars on the exhaust manifolds were supposed to be cut off. Probably a good time to upgrade the gaskets and exhaust bolts too.

In the mood to block off the EGR - or just plain delete it (depending on emissions regs where you live.
Marky... Quick question, you mentioned blocking off egr, what are the advantages and the disadvantages.
Actually, what does the Exhaust Gas Recirculation system do and how does blocking it off help the engine ?
You know I need to keep my CaliStupid smog equipment in place.
If it truly helps the engine run better with the proper pcm adjustments, I’d be up for considering it.
 

·
Registered
Joined
·
1,596 Posts
The EGR Valve's goals are to lower NOx and improve MpG.
Blocking off the EGR might cost 2 or 3 highway MpG, it's of almost no help under 40MpH, and of little help over 65MpH.

There are a myriad of potential drivability symptoms when the EGR fails - tough starting, stumbles, stalls, hesitations, rough idle, intermittent unpredictable and/or inconsistent power delivery, wasted fuel, and possibly knock during light acceleration or even cruising - and any or all of them could happen at any road speed.

I'd give up 2-3MpG to avoid those issues, as have many before me.
It can be merely disabled in the pcm without physically closing any EGR passages.
Some of those who prefer to avoid the chance that the EGR circuit will passively collect carbon to be reintroduced into random combustion events either delete it if they can, or block off the EGR circuit if it cannot be deleted.
 

·
Registered
1996 ImpalaSS WX3
Joined
·
371 Posts
The EGR Valve's goals are to lower NOx and improve MpG.
Blocking off the EGR might cost 2 or 3 highway MpG, it's of almost no help under 40MpH, and of little help over 65MpH.

There are a myriad of potential drivability symptoms when the EGR fails - tough starting, stumbles, stalls, hesitations, rough idle, intermittent unpredictable and/or inconsistent power delivery, wasted fuel, and possibly knock during light acceleration or even cruising - and any or all of them could happen at any road speed.

I'd give up 2-3MpG to avoid those issues, as have many before me.
It can be merely disabled in the pcm without physically closing any EGR passages.
Some of those who prefer to avoid the chance that the EGR circuit will passively collect carbon to be reintroduced into random combustion events either delete it if they can, or block off the EGR circuit if it cannot be deleted.
Hmmm...
I understand what the goal is of most emissions equipment, just not the exact physics of certain devices and how the devices are designed and implemented to do it.
An EGR recirculates exhaust gases into where, and then does what to the gases to increase the 2 - 3 mpg.
I’m myopic sometimes and my OCD demands I understand how things work, not just that they do.
I’ll do some more research on my own to better understand how and what it does, and why there’s an EGR mounting location on Edelbrock’s Performance Gap intake manifold, yet the manifold isn’t CARB certified as legal for use in CaliStupid.
All the emission control devices are accounted for on the manifold, with machining done to install them.
Thank you for the time and your response.
Your advice and explanations are always appreciated.
 

·
Premium Member
Joined
·
1,369 Posts
1st go get a compression gauge and check it out

Delete oil cooler lines get l94 adapter

change the seals in cover

delphi opti were 175 at summit

delete air pump

delete egr and egr solenoid

plugs wires

get a t-valve to purge air and a 1/4” plastic hose so you don’t ruin opti

check the opti vent hoses replace if I was cheap vacuum hoses

bypass the throttle body heater coolant

if engine out would maor Sure no snapped header bolts tap and dye As needed

get new motor mounts

go over all wires especially the ones to o2 and plugs for tranny for breaks

dont forget rear main grounds to head

and Check the water pump drive coupling Wear out a lot
 

·
Registered
Joined
·
1,596 Posts
Normally, exhaust just gets, well, exhausted out the exhaust.
Instead, a small portion of exhaust gets recirculated by the EGR Valve, back into the intake, to be re-compressed, re-combusted, and re-exhausted.

So as not to be redundant about the CARB, I'll point out that there are several mods that are very UNpopular with the ISSF and several other reputable IronBlock LT1 forums, and the Edelbrock version of our LT1 intake manifold is one of them, so CARB's neither here nor there.
 

·
Registered
Joined
·
8,487 Posts
Has the yellow cap Opti distributor. Which is AC Delco correct? You suggested new cap and rotor should I use one from O’Reillys Spectra Premium brand?
yes the yellowish cap is AC Delco. Just like any distributor look at the contacts for any wear and if so replace it with a new cap & rotor

I feel this is a better C&R than the other cheaper ones available and has brass terminals

 

·
Registered
Joined
·
8,487 Posts
Marky... Quick question, you mentioned blocking off egr, what are the advantages and the disadvantages.
Actually, what does the Exhaust Gas Recirculation system do and how does blocking it off help the engine ?
You know I need to keep my CaliStupid smog equipment in place.
If it truly helps the engine run better with the proper pcm adjustments, I’d be up for considering it.
A properly functioning EGR has no ill effects on the motor. In CA you can not remove it regarding Emission testing

Many switch to the Camaro "manual" transmission EGR when they install a more free flowing exhaust on a Impala.

Regarding the Edelbrock LT1 intake. It has zero performance gain but won't hurt anything....although there was a published thread that said it lost 1-3 HP on a dyno compared to a stock one.
 
1 - 20 of 21 Posts
Top