I bought a 1995 Camaro z28 5.7 LT1 the car was immaculate only problem was said to have was low oil pressure so my brother owns a mechanic shop that I rent office space from so it was no issue. We towed the vehicle and then came monday... I listened to the car I couldnt hear any knocking but I did not rev the motor

Monday on start up we reved the motor .. it was knocking engine was no good ok fine lets rebuild it with performance parts. Ordered almost $3000 in performance parts from Summit racing headers cam roller rockers lifters springs injectors you name it we were going to do it all. I was gonna have a 500 HP 95 Z28

We took the entire engine apart and the crank was demolished the rods were shot .. so at this point the motor wasnt rebuildable without spending another $1500 .. which I now wish I would have done. Instead I sent the parts back kept the headers and bought a used 97 LT1 from a pontiac firebird formula had some problems with it but got it started all 8 injectors had gone bad so we replaced the injectors and it fired right up. took us some time to figure that one out because in my brothers 30 years as a mechanic hes never seen all 8 injectors go like that we had them out of the rail and fired up the car to visually verify they were not throwing any fuel at all not a drop. Any ways on to the next fiasco we got the car running .. water and oil mixture super milky it was blown head gaskets .. we made the guy who sold us the motor replace the heads and everything needed brand new machine shopped cleaned up and hot tanked put them on did valve adjustments and the car fired up .. brand new parts we put into the car , brand new thermostat,radiator, spark plugs, all 8 injectors, redone aluminum heads, gaskets, fuel filter, water pump, optispark, oil trans fluid, oil filter pacemaker headers , spark plug shields and I think that is it.

Overheaded again in idle my brother is almost 100 % positive we have a cracked block somewhere I trust him but I want to see if anyone here has any experience with this motor and could offer another solution other wise I will be buying motor number 3 and trying it again Im already sunk too much time and money into this car and the only way to recover anything from it is to drive it out of this camaro. The car is beautiful body interior corvette wheels $2300 metal flake pearl type paint job its a bad *** camaro sounds like a beast with the headers but I need maby some input and or possibly a reliable source for a replacement LT1 I dont have all the money for another motor but I will have to get it together its been a month that I am with out a vehicle in texas you absolutley need a vehicle.

Any tips insights or useful info you guys can offer this car has drained me completley as soon as I found out the latest motor wasnt good I took about 8 beers to the face in less than 30 minutes .. its got me super twisted up. To top things off we did a tranny service and I think the transmission is no good either its sticking in 2nd gear.

Any help would be amazing I have wanted to smash this car but I absolutely love camaros and have always wanted one I just wish I would have reved this motor when I purchased it I would have heard the knocking.

 

How did he determine it has a cracked block? These thing are a pain to bleed the cooling systems on.

Anyway if you want a motor....
golen and victory racing engines both do short blocks for the lt1 i believe. you may want to contact them and ask them some questions. Never done business with either but its a start. Maybe do some research on them and see what you come up with.

LT1/LT4 Engines | Golen Engine

VictoryRacingEngines.com >> Where Quality Fuels Power!

 

[QUOTE=greenmachine96;676210]How did he determine it has a cracked block? These thing are a pain to bleed the cooling systems on.


He felt the compression in the cooling system coming from the radiator its in tune with the motor as if one of the water journals internally is cracked or dumping compression from the pistons into the cooling system. Im hoping maybe is could be something else but my brother is an amazing mechanic he can hear a car and tell you exactly whats wrong with it, other mechanics try arguing with him and his first inital assessment is almost 98 % always exactly the problem. Very Very intelligent and competent mechanic. I was just really hoping there are some true camaro gear heads on here who could enlighten us to something we may not know about the LT1.. hes an LS guy this has been the first and the last LT1 he ever wants to see...well technically gonna be the 3rd LT1 he encounters hahah

 

well dumping compression into the cooling system could definately be a cracked block. If your brother is an experienced mechanic and he thinks it has a cracked block then the only thing you can do is buy another motor. But if it were me i would still do a cylinder leakdown on it and maybe hook a radiator pressure tester on it to see if you are losing compression into the cooling system just to verify that is 100% the problem and not the extremely common air pocket that these things get in the cooling system. i went through an overheating issue with my car because i couldnt get the system to bleed correctly. Took me a couple of hours. But if your brother is a mechanic he can probably draw a vacuum on the system to help make sure there is no air in it.

 

Has he bled the system? As GreenMachine stated, these can be a bit of a pain to get all the air out of the system. If not done correctly, the engine runs hotter than need be and will cause an overheat situation, even at idle.

That aside, do you still have the block that came out the car originally? If so, why not just use that block and transfer all the internals from the one out of the Formula into it?

I also don't understand is, if you knew the original engine was knocking, why did you buy a bunch of performance parts unrelated to the problem (cam, rockers, headers, etc.) and not buy a new crank, rods, and bearings? This would have saved you more money in the long run and allowed you to have a running, new bottom end engine that you could upgrade later.

Keep with it though. There are knowledgeable people here ready to help every step of the way.

On a unrelated note, I feel sorry that your brother wants this to be the first and last LT1 he wants to see. These are good, reliable engines and can make power quite easily if one understands the benefits the LTx platform came with. Some benefits that neither the Gen I nor Gen III/IV engines had. I.E. Reverse flow cooling. Allows higher compression while staying pump gas friendly and cools the head more evenly, making hot spots less common.

 

the cost to rebuild a motor is as much as the cost of a crate motor. unless you have a machine shop. lt1 is a good motor. got to 200k miles on my first one and it was still goin strong when i got rid of it.

 

If you had coolant in the oil and the engine ran that way don't put any money in it. I have not heard of a Lt1 cracking a block but anything is possible. Where the heads tested for cracks?
The second motor didn't run and you bought without doing a coolant pressure test?

You made the comment the replacement motor had the same issue. Low oil pressure? never buy a used motor with issues. Your buying someone elses problems. Heck even if I am just buying a core to rebuild I want a motor with clean oil, pressure tested and no signs of recent overheating.

 

Yeah any time you buy an engine even crate engines or from a builder its always a good idea to do a cylinder leakdown on it before you do anything with it. Ive heard of crate engines and reman. engines with 20% leakage in every cylinder right out of the box. And in that case send it back. Any engine with more than 10% or so leakdown in any cylinder should be considered to possibly have an issue (even if it just needs valve adjustments).

 

Well I want to give a HUGE thank you to everyone on here who offered valuable input!!!

My brother had a stroke of genius. The lines off the water pump were ice cold on both sides with the car on and moving up in heat, so we pulled the water pump off and sure enough the tiny sleeve for the shaft that comes off the water pump was stripped so there was no water in the motor being pushed out of that pump replaced the sleeve with the other water pump we had here and the Z28 now hasnt come up not even to the first tick on the temp gauge.

She is ALIVE and the motor does not have a crack in the block .. just saved me like $2500

Now new smaller and much more manageable problems the transmission is a little sticky however its got a strong positive shift.

The speedometer does not read which I know that is picked up right there on the back of the transmission.

It does not want to go into park and needs a new shift cable.

The pan was siliconed by whatever dummy who had the car before and we found a few little pieces of dried silicone in the transmission pan so were hoping a trans shop can just clean that up and well be good however

Question: went to clear the codes on the engine and the scanner has no communication which could be the route of all all the problems. Is this camaro OBD I or OBD 2 ?? its a 1995 camaro z28 with a 1995 harness however its got a 97 pontiac firebird formula LT1 in it we kept the 95 computer and harness.

If we can solve the communication problems then perhaps that will clear up the transmission quirks because the computer controls the trans as well as speedometer sensors correct?

I was just told by our other tech in the shop that this car is OBD 1 but I havent even google searched it yet I wanted to thank all the guys on here who gave some very great advice that didnt solve the problem but inspired us to find the solution.. the compression in the cooling system was the water boiling .. felt just like compression from the block .. thank god it wasnt today is a GREAT day Id like to sort out this computer/ tranny deal and shell be buring through tires here in the next day or so. THANK YOU ALL!!!!

 

95 is obd1 with a obd2 plugin. brb.