thumping knocking oil light flicker

[91whiteshoplus]

My car: 91 sho with 198,000 miles, last timing belt was at 140k. Only engine mods is catless Y pipe.

I was on a long biz trip and i noticed a slight knocking from the engine. usually this happens with pinging from crappy/watery gas, so i ignored it, but it was still doing it when the engine got hot with premium gas. Then I got into a long traffic jam and the engine got really hot, and i noticed some flickering of the oil press light. I tried to minimize the driving, but Halfway home the knock becomes louder at higher rpms. As i pull into the driveway at home and idle, i can feel the engine thumping through the shifter ****. oil light flickering steadily now. havent touched it since.

My guess is the rod bearings are NG. whats that thumping, maybe the mains now gone too?. If anybody has any advice, ill take it. How big of a job to replace the rod bearings, i assume i can do it by just dropping the pan?

 

[Ishodu]

Rod bearings are not that hard to change, but gone as bad as you describe its going to need more than bearings. At this point I would bet your crank is damaged as well.

 

[SASHO91]

As marcel said, your motor is probably toast.

Might want to start looking for a new motor, or replacement crank and possibly rods.

when you said that the motor got hot. How hot? oil viscosity is directly related to tempurature. So, if your motor was on original worn RB's, and the cooling system wasnt up to par, this could lead to what happened, (a) spun RB's

 

[shoballsteel]

complete rebuild is in store and if you love car do and if not sell while still start!!!!!! i love all SHO so rebuild is in mind me thinks

 

[1993MTXSHO]

you really have to open it up and see how bad the bearings are, if your lucky al youll have to do is change the bearings. But definitly DONT drive it anymore.

 

[91whiteshoplus]

dead, i thot as much. gonna sell it for parts.

regards---

 

[thecrew2999]

you might be lucky and its not dead check first...
i had a tapping sound and it turned out my timing belt tentioned came off the nut let go haha..

what you wanna do it take the bearings off and use your finger nail to inspect the crank rods and caps make sure there is no scratches even if the bearing is spun you can get lucky and save it which is what i did because my one bearing was spun but didnt make a knock or have any scratches

 

[91whiteshoplus]

I took a look and yes one bearing is spun, the crank does need remachining but the rods and pistons actually look okay.

I am retiring it and I Put it up for sale as a parts car on ebay yesterday. This was not an easy decision. I bought this car 16 years ago new. It has been reliable and fun. But after 16 years, besides the motor problems, There are enough little things gone or going wrong that i just cant keep up with it. It is just wearing out. Bully to all of you who keep these cars going, thanks to those who contribute tips. Any old timers here from the original shotimes forum? Cant say how much help i got from those forums. Anyway, my old car has a bunch of good working stock and hi perf parts that i hope will find their way into shos.

best of luck and thanks!!