LS1LT1 Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
Stock lt1 in my 96 z28. I have gone through front of engine trying to locate oil leak. Replaced all seals on opti along with front crank seal with a new hub. It is leaking behind opti from some where. My mechanic has done everything he can think of. The only thing left he says is maybe a crank baring. Don't know what else to try. Help please, I got $600 into tryn to get this thing to quit leakn. Tx
 

·
Global Moderator
Joined
·
12,966 Posts
Did you replace the water pump oil seal on front cover. And have you checked the other seals that were put on for installation damage which can cause a new seal to leak.
 

·
Premium Member
Joined
·
5,011 Posts
other than mis-installation that damages the seal (VERY common with the waterpump drive seal).....

it could just be a groove worn in the seal landing on your shafts from dirt, high mileage, or just poor materials. very common with rotating parts in areas that don't get cleaned often enough, and no lt1 owner rinses off their timing cover periodically due to opti fear.

wear on a rotating shaft may be less obvious than you'd expect, as sometimes natural play in the shaft causes a back and forth 'polishing' effect that makes a natural-looking valley instead of an obvious dent. measuing the mating surface with a slide comparing to other points on the shaft (and checking against the specification of the seal) will help identify that problem, and shimming under the seal to relocate it can solve such problems on the cheap without buying a new shaft.

also inspect your PCV system, if your crankcase is becoming pressurized, all bets are off, it'll just blow oil.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #6
Water pump seal has been replaced, my engine guy took everything apart a third time saying that he didn't bruise or damage any seals. The pcv system was gone through and everything seem to be ok, new pcv valve and new hoses and such. When we put opti bak on last time we cleaned up the rotor on it that makes the contact with the camshaft. Then when we pulled it apart the last time u could see wear on one side it was rubbing hard and the opposite side was barely touching. Would like to find someone who has worked on lt1 engines before. The only place I can find is the dealership and they r charging bout 90 an hour. And I went there first and they just wanted to replace front main seal.
I need to find a decent pic of pcv system to make sure that is all correct on my car. I do want to put in the lt4 hot cam with the 1.6 roller rockers anyway. I hope that will solve problem. I gots to get back to bed . Will be back on later in the evening.
Many thanks again
 

·
Global Moderator
Joined
·
12,966 Posts
shbox.com has pvc system diagram and much other good lt1 info. 4th gen section sticky threads has both 96 factory service manual & 4th gen parts books, all available for download.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #8
I would like to find a mechanic experienced working on lt1 s in the westcentral part of Wisconsin or eastern parts of Minnesota to work on my z28. Any help appreciated
 

·
Registered
Joined
·
10 Posts
Discussion Starter #9
thanks for the heads-up on shbox. checked out my pcv system and everything seems to be in order. threw dye in my oil and brought engine up to operating temp. 185* till fans came on. not a drop of oil. got in and reved it up acouple of times and got bak under z and could just see the oil starting to seap out between opti and block.im thinkn its the cam bearin. time to put in that lt4 hotcam? I think my problems would be solved. take it apart replace what needs to be replaces for the cam, throw in a new oil pump, open up the bottom end and check crank and replace main bearings maybe a port and polish. I got 3 grand to spend and I want most bang for my buck with engine. like to get round 350hp to the rear.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #10
I just picked up the LT 4 hot cam and a set of roller lifters for my z28Should I put in the 1-6 Roller rockers For maximum Performece from the cam?Was wondering about any other suggestions Of engine components I should check / replace / upgrade while I have the engine out
 

·
Registered
Joined
·
3 Posts
It’s the poorly designed water pump shaft seal. You have to research how to successfully replace it. There’s a special tool so it doesn’t flip backwards. Worst thing I’ve ever seen.
 

·
Global Moderator
Joined
·
12,966 Posts
Most people who do the seal replacement make their own install tool. Stuff like the lid off a sharpie marker have been used as a substitute install tool.

Few years back, I built the special tools needed to rebuild a 700r4/ 4l60/ 4l60E transmission. I used galvanized steel pipe, pieces from old gear pullers, & other stuff I had laying around. Saved about $1000 this way.

My point being; learn to improvise and work around expensive special tools.

And welcome to the forum. Did you happen to notice this thread is 4 years old? But don't worry, we all revived dead threads when we were new.
 

·
Registered
Joined
·
3 Posts
Thanks about the old post. I made my own from a marker cap and it flipped over anyway. After my second attempt it worked. Problem is that you can’t see if it flips so you have to pray. Like I said, really bad design
 

·
Global Moderator
Joined
·
12,966 Posts
Those bad designs, I believe, are done on purpose. It gets people into the dealer shop. If you think the wp seal is bad, wait for the fun you'll have with the optispark distributor.

Words of advice. Buy a $70 PC based oscilloscope. It is the only 100% way of checking opti low & high resolution signals. Also good for the pesky 50 hertz fuel enable signal that security system sends to pcm to enable fuel injector operation.

And when opti fails, buy only GM,Delco, Delphi, & Msd. The rest are garbage.
 

·
Registered
Joined
·
3 Posts
I have a 97 WS6 and it’s running great. I changed the opti spark about 40k ago with no problem, but I noticed you had to be very careful when you’re installing it because it will bolt on in the wrong index and you could break it or worse yet not break it and reassemble it out of time
 
1 - 15 of 15 Posts
Top