My Supra is sick, please help me!
 

hey guys my 89 supra started getting sick today. Its been leaking oil from what I belief is called the rear seal for a while now. But today, I was using it and all of the sudden when I reach 2500 RPM's in any gear, my engine starts doing this wierd type of knocking noise. I checked my oil and its clean. Ive been told that it might be my lifters, but if anyone can help me please do. I also noticed that my oil gauge stays low.

:(

sounds like rebuild time..... one of the bearings has gotten starved of oil...

so either rebuild or buy another engine

I know you know more than my friends, some where saying that it might be the lifters that had gotten loose, but the knock is too deep, and another one said that he was pretty sure that it was a ?crank? (he said that they were the things that push the pistons) that got loose. But its wierd because when I turn it on it sounds like it was fine but its until i accelerate that it does this noise. Thanks, do you know of any websites that sell these engines or phone numbers? By the way Im going with the 7M-GTE, Turbo power baby!, What would I need to upgrade?

Well there really are no lifters on your overhead cam engine. The cam rides directly on a shim that sits in a bucket that pushes directly on the valve. The tolerances are tight so that is why there is none of the clicking noise on a normal solid tappet design. That is not where your problem is though unfortunately.

Down deep are the connecting rods and they are usually the first casualty when something gets starved of oil. If your engine is a few quarts low and you hit the brakes hard or go into a turn hard, the oil sloshes away from the oil pump pick up and starves the system of oil. The coating on the bearings quickly heats up and melts away the lead base part of the bearing and rubs on the crank and it gets worse from there. Normally there is only a few thousandths clearance between the bearing surface and the crank so at start ups in the mornings there is probably a very slight but non detectable rattle, but the oil film that is there and the oil that quickly builds up takes up that space and the oil cushions that clearance.

If the surfaces get worn away, normally or due to a lack of lubrcation, then the clearance gets too large for the oil to cushion and the bearing surface hits on the crank, especially on the compression stroke and that is when you get that deep rattling sound form the bottom end. As you can guess, the bearing needs to be replaced and usually the crank needs to be reground. While you are there you start checking other parts and find that you may need pistons and main bearings, head milling and block resurfacing and then at least you need to replace the valve stem seals.

The rear seal does dry out and starts leaking. They are cheap and relatively easy to replace, but not everyone has the facilities to do that, so keep pouring in the oil and hope, but eventually........well you know, low oil, then the death rattle, or worse. I just got an 87 Supra that had the same problem it looks like. The owner, who had the junkyard pick it up said he thought it was the timing. Beautiful car but it wasn't the timing as much as it was the large hole on the passenger side of the block! That is what happens if you let it rattle too much. Also it looks like it caught fire in that area too!

Good luck, but get it rebuilt by someone that knows at least a little about foreign cars.

Russ