OK, Here it is: 1988 T/A. TPI 305. automatic, 130k miles. Just bought the car recently, and pretty sure the motor has never been apart before cause it's a one owner car ('til now). I've been hearing a sound that i thought was maybe coming from the ps pump or the alternator; like a roller bearing, or ball bearing making noise intermittently, or a few bb's being swirled around the bottom of an empty plastic water bottle. It's hard to describe, sort of a metal gently scraping on sheet metal sound mostly at idle after the engine is warmed up, and it kind of comes and goes. I removed the serpintine belt and started the engine, and i still here this noise with the engine running and nothing except the crank pulley turning...It sounds like the timing chain is stretched/stretching and rubbing against the cover. Anyone ever heard of this happening before, or found this to be true in their case?
Thanks,
John C.

 

Both my 305's do this, I'd like to know what it is.

 

My 350 did that for about a month, about 500 miles. A year after (about 2000 miles) a new chain and gear set was put in, so I don't think the chain stretched. I actually think it was the cam walking out (had a flat tappet cam) and then hitting the cover. Then one day it stopped, must have self clearanced itself. I'll be taking my motor down this winter and I'm still interested to see what happened.

 

So, you guys are still driving the cars making this noise and have had no problems other than hearing this sound? BTW, Does the '88 305 tpi have a roller cam, or a flat tappet?

 

88 has a roller cam

 

I braved it out just driving it around. I knew I was putting a TPI 383 in it's place soon enough without using anything but the headers from my 350 so I didn't care.

Realistically on a Saturday with a handful of free hours with just purchasing a timing chain cover gasket, water pump gasket, and possibly oil pan gasket, you'd have plenty of time to take off your cover and see what's going on. Maybe your roller cam retainer got lose? The timing chain isn't the hardest part to get to on the motor. Don't forget to borrow a harmonic balancer installer/remover from your parts store.

 

Yeah, I don't need this car for a daily driver, (bought it for 15 yr old son's first car, but he can't drive alone till he's 16 in a few months) and I have to take half of the intake off anyway in order to replace the injectors, so I've thought about going ahead and pulling everything except the heads and just replacing the cam/lifters and timing set with new ones. Maybe with a little better profile than the stock cam. Car has 129K miles on it, but doesn't burn any oil as far as I can tell (no smoke) so I don't really want to do an entire re-build if I don't need to. I'd rather keep this one up for a while, and then If the boy acts responsibly with the car, maybe put a different/bigger motor in it later on. Is it necessary to replace roller lifters when a new cam is installed, or can the old roller lifters be re-used without damaging the new cam? Not too familiar with roller cam. Ive only had experience with engines that have flat tappet cams in the past...

 

You can reuse roller lifters to your heart's content.

 

Cool, that's what I thought. Just wanted to be sure.