jrappl

Well, I'm waiting on parts...
I ordered a set of injectors and received them today from FIC.
I've ordered and am waiting on a water pump, hoses and belt.
I decided to go with the Petris Opti with the vent kit but I can't order it until tomorrow as they are at a show and not taking orders until they get back.

My plan is to install the injectors first (tomorrow maybe) as it should be a quick job, retest and when it fails replace the opti, water pump, hoses and belt as they all appear to be original and at 22 years old I think they did their job and are ready for retirement!

BTW: I don't think the injectors are my stalling issue but it does idle a little lumpy and I have one out of spec so I'll address it now. After much reading and viewing videos of the injectors actually working on a bench setup I went with the Bosch Design III.

Winnin'

Mine had the exact same symptoms. It would run perfect when cold and immediatly run like crap when it got to about 190-200*. It was the opti.

jrappl

Did you replace it with a rebuilt AC Delco, a Delphi or did you go with something else? How long ago?

lt4obsesses

When you order the new opti, be sure that it includes a new opti harness. This is th ewiring that sends the signal from the opti to the ecm where it is sent to the icm and the injectors.

If you smelled coolant, try and find out exactly where it's coming from. It very well could be from the weep hole in the bottom of the water pump. Another common leak place is from the hose going to the throttle body, hidden and can slow leak for some time undetected. This will leak right onto the opti harness connection.

jrappl

Status update. It's been weeks since I've had time to work on this...

I installed new Bosch Design III injectors today. I did not think they would solve the stalling problem but with one out of spec and them being original and 22+ years old I thought it was time.

The new injectors are flow matched from FIC. It was an easy install - about 40 minutes total including pulling the front tires to get easier access and spending some time cleaning the rails and manifold well.

Car started right up and ran great. Took it around my private road a few times and then let it idle. It got to 228 degrees and the cooling fan came on. In the past a minute or 2 after this the engine would sputter and die. Not today. The cooling fan ran for a little and dropped the temp to 215 and the fan went off. I let it cycle doing this 4 times. Still running great. I took it out on the road. Ran better than ever. Even the rumble I used to get when the torque converter locked up at 41 mph was gone. I drove around the neighbor for 15 minutes, decided it was fixed and headed home - and it died... Waiting for it to cool so I can drive it home.

I just ordered the Petris Opti-spark and the cooling fan kit today. I already have a new Gates water pump on hand. Looks like I'll start ripping it down tomorrow.

A couple questions.

Should I replace the water pump and opti seals. I see the water pump one needs special attention to get it in right without flipping the seal edge. Is the opti seal difficult too?

I have an oil leak from the valve covers. Does the alternator have to come off to change the driver side gasket? Does the EGR tube have to come off to change the passenger side?

I'm going to change the plugs and wires while I'm there. Any tips on how to get #5, #7 and #8 plugs out - they look pretty tight.

Winnin'

Sorry for the late reply man, everything you are describing sounds just like mine when the opti went. I replaced it with an AC Delco unit. Shortly after, I had the entire motor rebuilt. The opti did fix the problem though, and it ran great. Now, I have new everything. Good luck and keep us posted.

these threads help alot of people out.

Silver96ce

I'm currently working on my '96 LT1 for the third time in three years. First time I replaced the water pump and inspected the opti which looked good. I had just bought the car and over the years I have lost trust in the baloney a lot of sellers tell me. Last year I had to pull the opti as it went bad. I changed the water pump seal with the timing cover on the engine. But I could not get the opti seal out so I left it before I damaged it. This year, the opti again! It was an MSD and they rebuilt it for free since I paid to have it rebuilt last year. Hopefully it holds up this time.

But I also decided to do more work. Intake gaskets, timing cover gasket, water pump seal, opti seal, crank seal, oil pan gasket and oil filter adapter gaskets. Mild cam, valve guide seals, and springs. Let me tell you I had a heck of a time getting the opti seal off the timing cover even with it off the car. Ended up carefully using a brass drift to slowly knock it out from behind. So if it was me I would change the water pump seal and leave the opti seal if it is not leaking.

As for the driver valve cover, I removed the alternator to get it off. It only took a few minutes and it was pretty easy. I also removed the EGR tube from the top of the exhaust manifold to make it easier.

Numbers 5 and 7 plugs haven't given me much trouble but number 8 well that is a different story. Getting it out was hard but getting back in is a real bear. Last time I used a short piece of tubing (I think fuel line) to help get it back in. This time I am going to see if I can get it from underneath since I have the passenger cat off (to drop the oil pan). Good luck.

jrappl

I think I will leave the old opti and water pump seal unless leaking badly. I've read a thread or two on replacing the water pump shaft seal using a socket or a marker body instead of the GM tool. Is the lip really paper and not rubber? I ordered the Felpro timing cover gasket kit but don't have it yet.

I'm planning on doing the plugs, wires, cooling fan kit, opti, water pump and thermostat all at the same time. Hopefully that will finish it and make it reliable. Changed or check just about everything else - with the possible exception of an ECM with a thermo problem...

Just to make it easier I'm going to pull the wheels and inner fender covers and I have a lift so I can work above or below as needed.

I'll take pictures and post as I work on it.

Silver96ce

Last time I used the marker trick but this time I am using this -

http://www.ebay.com/itm/92-97-LT1-L99-Water-Pump-Drive-Seal-Install-Tool/290684677748?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D24353%26meid%3Db08db003ac994e11b160abf84bf29747%26pid%3D100011%26prg%3D10335%26rk%3D1%26rkt%3D10%26sd%3D330860004305
Hopefully it will make it easier. As for the composition of the two seal gaskets, yes it has two - one black and one yellow, I don't know. The outer yellow one seems almost like teflon but I would think it is thin rubber and the inner black seems to be a regular rubber gasket.

LannyL81

The FelPro timing cover seal set includes the three shaft seals and the cover to block seal. Just take the timing cover off and tap the old seals out from the back side using a drift punch or similar.

All the seals just tap in from the front; just put a block of wood on the inside of the cover before doing so, this way you will not crack the aluminum cover.

I have used the HiLiter body tool several times and it works just fine. The trick is to keep the water pump drive seal lip forward when re-installing the timing cover onto the water pump drive shaft.
I always use a small amount of RTV on the timing cover to block gasket; holds gasket in place and to me just seals better.

However have to be ready for cover re-installation: apply RTV to the block, put gasket in place, apply RTV onto cover and have HiLiter body in place....and then put cover onto block while ensuring the water pump drive seal lip does not fold inward....gets a bit involved!....but not too bad.

I still think the problem is the ECM and not the Opti....but just my opinion.

Good luck to you.

jrappl

Ok, I'm a little confused on the water pump shaft seal. If the seal lip needs to keep facing forward wouldn't it just push on then? When pushing the seal (or timing cover) on the shaft wouldn't the shaft push the lip forward and keep it that way? I must be missing something, maybe I'll see when I get to it.

And yes, I'm not at all sure it is the opti. It's current ECM is a junk yard replacement. My guess is that the previous owner had this issue and tried the ECM swap, it didn't fix it so he gave up and auctioned it off. Of course he told me quote: "Runs great, drive it anywhere". I trailered it home and it failed on my second drive. I can take it for short drives (10 minutes or less) but it fails every time when it gets fully warmed up. Since it still has the problem with the second ECM I'll swap the opti. Would be nice if I had a spare ECM to test with - it's a 10 minute swap at the most...

I have had the ECM off and apart. It looks ok, I didn't see any bad solders or burnt components. There is a protective coating on the board that is starting to degrade. All the connections look good.

Whoever swapped the ECM did break one of the hold down clips for the PROM but it's still in all the way and tight. The ECM does seem to get hot. You can put your hand on the metal ECM cover without getting burnt but it's hot.

Someone also posted a video of an opti being worked by hand. It works fine when cool but it's dead when hot (heated in oven to 250+ degrees). Maybe mine is the same way.

Silver96ce

The water pump driveshaft seal really has two seals - an inner and outer seal. The outer seal is easily torn on the splines and the tool is used to keep it stretched and not torn. You'll understand when you see it.

Lanny - to take the timing cover off he has to drop the oil pan. Otherwise he could damage the pan gasket. And if he drops the oil pan, he'll be better off with a new pan gasket. More work. And per the FSM, I took off the exhaust, passenger cat, starter, oil level sensor and oil filter adapter to drop pan. In doing that I snapped two exhaust flange bolts (one on drivers side and one on passenger side). More work than I think he wants to take on at this time.

jrappl

Ok, now I understand the seal issue - thanks, this forum is a great help.

I don't plan on pulling the timing cover because of the oil pan but you never know. I may change my mind once I see the condition and leaks. From what I can see with everything still in place the front of the engine is a little grungy...

LannyL81

Silver96ce: I by no means was giving a step by step instructions on how to take the timeing cover off. Yes the oil pan has to come off, so does the starter and inspection cover, oil filter, oil filter adapter, oil level sensor.
I did not have to remove anything else on the '95 and '96 that I have done; your year must be different...IDK.

jrappl: dropping the oil pan is not difficult, at least it was not on my '95 or '96, as long as you can put the front of the car on jackstands and have a nice concrete garage floor to lay on. Would not want to do this on gravel or the ground.

The only hint needed is that the crankshaft must be rotated so that the crank counterweights are up to enable the oil pan to be pulled towards the rear a few inches before it drops down.

The one piece FelPro oil pan gasket is the ONLY way to go.

jrappl

Started on the opti today. So far not too bad, just over an hour and I have the water pump out. Done for the day as I am not in a hurry because my parts aren't here yet. Suppose to get them tomorrow...

I have a few pics: before I started, after the hoses and electrical connectors have been removed, nasty looking front of the engine, the failed water pump bearing... It's so loose it must have been leaking but I never needed to add any coolant - of course because of the reliability issue I've only put a couple hundred miles on it.

You will notice I did not pull the TB. It looked like I could get the water pump out without and that is true but I'm going to pull it tomorrow to get better access to clean the front of the engine.

jrappl

I have new hoses, belt, water pump, opti and plugs and wires.

I didn't order a new coolant temp sensor so I guess I'm off to the parts store tomorrow. I don't really want to use the old one.

jrappl

I removed the TB for easier access for cleaning and the alternator because I will be doing the valve cover gaskets before I'm finished.

The crank pulley was not too bad, used a 1/2" breaker bar with a 5/8" impact socket for the bolts. A big hammer on the breaker bar provided the "impact" needed. Then I used a short piece (14-16") of 4/4 oak and the big hammer again to tap it out from under the car. I was able to get to most of the bottom half and got it started coming off, touched the key to move the crank a little and finished it with one more tap. Ok, slightly more than a taps, but I didn't have to go nuts on it either.

Pulling the wires off the opti was harder than getting the pulley off. Anyway, 3 more bolts and the opti was out. It is a mess on the outside. The pictures show it after I had knocked the heavy stuff off. I don't have the reverse torx driver needed to remove the cap, looking for a screw I can use. I would like to see what it looks like.

Guess I will do the water pump seal, the opti seal looks good.

Silver96ce

You've made some good progress. You can get a cheap set of deep e-torx sockets at Harbor Freight in Raleigh local to you. Here is a link -

http://www.harborfreight.com/6-piece...set-68017.html

At $8.99 it's a steal. I bought the Gearwrench set but I would have bought this sets since the small e-torx use so little torque to install or remove.

From the looks of your photos you have a leak at the front (and probably the back also) of your intake manifold. This is common. The front and back walls of the block are called the "China Walls" and use sealant that often leaks after a time. Do a search and you will see more than a few threads dealing with it. Most recommend using "The Right Stuff" quick setting sealant along with new gaskets for the intake ports. I am in the process right now (along with other work). I am going to use the "dimpling" method to help seal it. Dimpling involves using a hammer and pointed punch to make a number of small dimples on the front and back wall and on the mating surface of the intake. It is believed that the dimples will help hold the sealant in place.

Before you install the opti, put a drop of blue Loctite on the rotor screws to help keep them from loosening and falling out. It is somewhat a common problem.

Before you put the crank pulley back put a liberal amount of anti-seize on the back where it meets the crank pulley and on the nose of the hub it slips over. If and when you have to take it back off again, it will make much easier. I had a bear of a time getting mine off the first time and it was a breeze the second time a year later with the anti-seize on it.

jrappl

Thanks for the link on the e-sockets. I'll call and run over today. I haven't been there in a while so I'm sure I can waste an hour or so shopping...

As for the intake leak, I was concerned that the mess was coming from higher up than the water pump seal. The left side (driver's) of the engine is wet with oil also. That's why I was going to change the valve cover gaskets. The back of the engine is not too bad.

With as bad as the front and side of the engine look, it doesn't really leak much oil. I've only noticed a drop or 2 under it in 8 months or so.

I've looked into the intake gasket on the LT1 and I think I will wait. I really want to get this opti done to see if it fixes the problem. There does not seem to be much overlap in what I have already done. The TB would have to come off again but it's a clip and cable and 4 bolts. And I just changed the injectors and would really like to run them a little before pulling them out again.

I am looking for opinions. What are the pros and cons of bypassing the TB coolant hoses. I've seen several people say they just put a short section of hose in under the TB.

Silver96ce

As to bypassing the TB coolant hoses, all pros, no cons. The factory routed coolant through the TB to avoid frosting problems in extremely cold weather. Your chance of having the TB freeze up is between slim and none with none way in the lead. With it bypassed, removal and installation become very easy. It was one of the first things I did. And I have driven the car on more than a few cold winter days without any problem.

And you're right, there is no reason to rush on the intake gaskets at this time. It took me two years to get around to it.