Does the oil pan need to come off the engine as well to change the timing chain in an '88 305 TPI or can you change the timing chain by only removing the timing chain cover? Thanks

 

Weeeell... The oil pan bears against the bottom half of the timing cover... So at the least, if it's still stock, you'll have to loosen the pan. With a 1pc rear main seal pan, and a 1pc rubber oil pan gasket (86-up) you can maybe loosen the pan, pull the timing cover, do your work, and then just reassemble. In the old days, of multipiece paper gaskets with rubber ends, it was pretty common to just dope the front of the gaskets with RTV before tightening the pan and cover, since the gaskets would be reused. Wasn't the "right" way to do things, but 2pc rear main engines leaked oil everywhere anyway.


Long live the rubber gaskets and improved 1pc mail seal!

 

As Drew stated it can be done but there are risks involved. Again “back in the day” in dirt track or wherever we would attempt this and use tin snips trimming the top edge of the front seal channel ever so slightly. Just enough to allow things to “slide” back into place. Right stuff RTV is your friend here, as well as minimal crankcase pressure. Fingers crossed never hurt no one either! Nowadays with some hindsight installing reusable one piece oil pan gaskets or a two piece timing cover is the preferred way to go.

 

I didn't need to touch the pan on my LB9. I was able to remove the timing cover and then snip the edges. It was easy. IIRC, I used high temp copper gasket stuff and have had no leaks in almost two years. I was very careful to clean, apply, and let cure that portion of the job before I ran the engine. IIRC I gave it 24 hours.