ovrebo1

I bought this 92 Corvette in 07 with about 114k on it. I sold it to my parents about a year later. I acquired it back late 2013 because they could no longer afford to pay mechanics to work on it. It sat at my house for about a year because I was to lazy to work on it. Late 2014 I finally fixed it.

When I got it back it died frequently for no reason and then would not start. So I thought Optispark of course. I R and R'd the Optispark, while I was in there I did the timing chain too since the car now has 156k. Updated the water pump to eliminate the throttle body water inlet and a host of other TLC items. All of that seemed to fix the random dying problem, but it now leaks a ton of oil. I took the Optispark off and R and R'd the two shaft seals for the distributor and water pump thinking that maybe I fowled them up. Car still leaks.

Gave it to a mechanic friend that vowed he would get to the bottom of things and get it fixed right. Got the car back from him, after he said he replaced the oil pan and valve cover seals, and drove it around and took his kids to school twice and it didn't leak. I got home after picking it up and there was oil all over the place like he had done nothing when I got home.

I took the Optispark off today and found oil in the distributor. The car had been breaking up at higher RPM's so I though maybe oil was getting into the optical sensor. I also though maybe the ebay Optispark I installed just wasn't sealing to the timing cover right, so I bought a Vatozone Optispark today.

Reassembled the car this afternoon and it runs great and pulls all the way up to red line, unlike it did before. BUT it still leaks oil..........

sluggballz

A big oil leak prone area is the intake. Specifically the china wall area. Have you checked there? It would leak down and behind the opti from there.
I replaced the intake gaskets on my 95 last week. I thought that was my oil leak culprit, but it turned out to be the opti seal.
Good luck. Keep us informed.

don hall

Your opti repair time must really show an improvement.

From a suggestion posted to help determine oil leaks,
place newspaper under the area you suspect the oil leak. Although oil will travel the path of least resistance, it may direct you to the source (?).

I should note the 'oil leak' post was titled: For Dummies..... that is why is I took interest.

ovrebo1

The oil is accumulating on the cross member under the balancer. When the balancer, Optispark and water pump are off. The oil trails look like they come from the Optispark drive seal. Not the China seal unfortunately (thank you for a new suggestion though).

Before I took it apart today, I watched it idle with an camera and it looked like it was seeping from behind the Optispark.

Keep the posts coming and I might remember additional trouble shooting details, plus I can post any pictures requested.

1800Wing

When you pulled the front cover to change the timing chain,,,did you replace the oil seals for the Opti drive and the Crank ?

later. tiny

don hall

Some reading, if interested:

https://www.corvetteforum.com/forums...1&p=1589644904

http://www.corvetteactioncenter.com/...-oil-leak.html

http://www.digitalcorvettes.com/foru...p/t-12124.html

ovrebo1

I sure did and I pulled the timing cover again and replaced them again, thinking maybe I did them wrong on round 2.

ovrebo1

I looked through the links. only thing it brought to mind, was I could dust the front of the motor in baby powder. That has helped me locate hard to find leaks in the past.

1800Wing

Well Nuts....cover warped maybe ? I can see where this would make ya crazy. Torque spec is 106 INCH pounds on my 96 .

later, tiny

ovrebo1

Covered it in baby powder. Went to the store and back and this is what is looks like.

1800Wing

In those last two pics....Is there a bolt missing ?...in the crevice between the cover and the front of the block, I can't make out a gasket. Not trying to be a wise-axle....

later, tiny

ColaBear

No that is an alignment pin. There is a total of 4 on the front of the LT1.

I wonder if Teflon thread goo might help for the bolt holding the Opti plate in that area that looks like a leak at the bolt?

The other leak looks like the main hub seal. Do you remember if there was a small grove around the hub shaft where it mates with the timing cover seal? If so, you can try a hub seal sleeve. It presses over the hub shaft and it much cheaper than buying a new hub.

TorchTarga94

There is your leak. When you removed the hub to replace the timing chain and then reinstalled it. There is a groove that gets worn on the hub from the seal, when you go to reinstall it you will never get it realigned perfectly. Sleeve the hub or buy a new hub, and replace the seal. FWIW I tried to sleeve my hub with no luck. I purchased a billet hub from nook and tranny and it solved most of my leak problems.


Just keep in mind its an LT1 and it will leak regardless. Too many seals and gaskets on this engine for it not to leak somewhere.

ovrebo1

I checked the hub for grooves when I did the timing set. I learned that lesson a few vehicles ago. This hub looked fine to me, but a new hub has def been in the back of my mind if nothing else.

Pulled it apart after a 200 mile weekend trip. Lost almost a quart of oil.

I know the RTV doesn't belong on the distributor, I just put it there in hopes to slow the leak. The oil still seems to be coming from the Optispark drive shaft. When I pulled the distributor off, the style Opti I bought this time has a removable shaft and it stayed in the cam when I removed the distributor. The seal didn't look like it was sealing very well around the drive shaft. When I turned the seal around, (so the spring was on the distributor side) it seamed to make a better seal.

ovrebo1

And if you look at the weekends worth of wear marks on the drive shaft, I think they should be closer to the distributor

ovrebo1

I had to update this since EVERY SINGLE OTHER THREAD I looked up where people had the same symptoms, people never updated the thread with the solutions.

I put UV die in the oil. Drove it to work and back. Tore into it. Via the light (I wanted to post pics, but the phone doesn't pic up the light) I saw that the water pump seal was leaking as well as the Optispark seal.

I attempted to install the pump seal and ripped it on my first attempt. I looked up the marker trick and why people have so much trouble with that seal. Obtained a new seal. I couldn't find a marker the right size, so I ended up putting the seal on the little drive spline connector, then putting it on the motor side and then tapped the seal off the connector and into the cover.

I turned the Optispark seal around so it looks wrong to me, but when I took it apart it didn't look like the spring portion of the seal was contacting enough of the Optispark drive shaft so I inserted the seal into the timing cover with the spring side towards the Optispark.

Idled in the garage last night for awhile, drove to dinner and back, drove to work and back toaday. So far cross member is clean and no smell of burning oil.

If no further replies considered it solved.

Silver96ce

If you ever need to reinstall the waterpump seal you can one of these -
http://www.ebay.com/itm/92-97-LT1-L99-Water-Pump-Drive-Seal-Install-Tool-/290684677748?hash=item43ae282e74&item=290684677748&vxp=mtr
I, unfortunately, had to pull the water pump three times in 2 years. The first time I saw the water pump seal was leaking and I used the sharpie trick but it was harder than I expected. The third time I decided to replace most of the engine seals so I bought the seal installer from Ebay since I got a new water pump seal in the timing cover kit. Went on very easy.

ovrebo1

Ya. Once I read up on how people mess them up it clicked. I replace fork seals on my dirt bikes and shaft seals on my truck shocks and there is a lip on them that rips the seal in a similar way.

Lloyd Smale

I silicone mine when I put it together too but I did it to keep oil out. If its your opti seal leaking and you sealed that up its just going to fill with oil and likely the oil will make it into your distributor.