Hi All,

I'm new to this forum although I've had my 'vette for about a year, but I'm having problems and need help

My car is a '72 BB LS5 with 3-speed auto. It developed a strange noise and lack of drive at the weekend, which it has never done before. I'm not a mechanic, and I've had my local garage come out to take a look but they don't have any ideas either.

The car will drive for about 2 minutes, then develops a strange high pitched noise from the engine (seems to come from below the distributor) which rises with the revs. Once the noise starts, there is no more drive in any gear. Engine revs but car doesn't move.

If I switch off and restart, it will run - has drive and car moves - for another minute before the whole thing starts again.

The engine temperature also seems to rise pretty quickly, almost to the point of overheating (I shut off before that happened).

Transmission fluid level is normal (measured with engine running) but does look brown and might smell a little burnt (could just be old though?). I had an MSD conversion fitted a few weeks ago, and engine heads rebuilt (hard valve seals) a couple of months ago, if it makes any difference. Up until this weekend it was running fine with lots of power and no problems.

Anyone have any ideas, before I go for an overhaul of the torque convertor? Finding people over here (I'm in Belgium) who know about 'vettes, especially big blocks, is not easy!

Thanks

 

W.A.G. here, but sounds like transmission pump. The fluid wouldn't move, and would heat up, would transfer heat to the radiator, which would in turn heat up the engine.

 

Thanks for the reply, I appreciate it - especially as that's something that nobody has suggested so far...

How would it transmit heat to the radiator though?

 

Automatic transmission fluid moves through steel lines to a tank on the radiator for cooling.

Some cars have external transmission oil coolers, but I don't think any vettes do.

 

and heat transfers to the rad via the tranny cooler that is inside your rad.

 

It's time to drop pan on trans. Sounds like filter is restricted at the least.

Get a good quality filter and see how it does. Look for debris on pan that indicates wear. There will be a little for sure..kind of gray gunk, but if you see metal particles etc time to pull trans. It won't grow back regardless of miracle stuff that people tell you to pour in it.

JIM

 

I can safely bet that the front pump on the trans is going. Before you do any other serious damage to the trans, replace the pump. If the fluid is already turning brown, then you are close to burning more parts. Get it fixed right away.

 

Thanks for the ideas and advice guys. I didn't even know I had a transmission pump! :o

 

Pump is inside of the transmission this is driven by the torque converter. It is also a good idea to have the converter flushed when you pull the trans. This will have to be done at the trans shop.

ltlevil