FE light tap & rattling noise

[priobe]

Why not try a set of Remflex gaskets. If you truly do have an exhaust leak and both surfaces are pretty much flat, Remflex will seal it.
But since the headers are off make sure surfaces are flat if not mill them down on a large belt sander length of the header

[DanEC]

Other than carefully setting the lifter preload to .035 to .040 roughly (cold) I haven't really dug into the motor. Trusting Keith and his guys to have put it all together right. The heads are 61 castings and he worked them over top to bottom so I'm sure the exhaust side was checked and lightly milled as necessry.

I can't really do much to the sealing surfaces at this point. I have full length undercar exhaust and removal starts with the tail pipes and it's a ***** to get the whole thing removed - just reinstalled it. The headers pipes are all individual - no common flange. I checked them out before installing and they looked great - flat. Motor is in the car - clearance is tight - not planning to remove anytime soon. Probably just install the Fel Pro 1442 gaskets and drive it for awhile and see what happens.

I would have tried the Remflex but it's virtually impossible to order gaskets for the early LR heads on line because the gasket producers don't differentiate between the high port and the low port heads. I pretty much have to order by picture, judging the distance between the upper bolt hole and the top of the port opening. As a result I have a new, un-used set of SCE low port copper gaskets if anyone is interested.

[DanEC]

I played around with it some more today and after a short drive I decided it is a little better after all. After it gets good and warmed up the ticking is pretty much gone although it still has a bit of that strange light rattle when coasting down - kind of like what Kevins2 posted. I did see a slight sign of a collector leak on one pipe when I first started it up - in a strong light I could make out a light wisp of smoke rising from it for a minute or two (probably from the sealer cooking off). it ticked a bit after first starting too so maybe it's this joint and right now it's sealing off when it gets hot.

I tried the tissue paper on the end of a piece of wire but didn't have much luck with it as touching any part of the car made it shake with the engine lope and also I had to contend with the alternator fan and the cooling fans cycling on. It looks to me like the exposed part of the exhaust gasket around cylinder 1 is getting carbon discolored already so I just don't think these copper gaskets can seal up right. Hopefully the Fel Pro ones will be here in a couple of days.

[DanEC]

Installed the Fel Pro gaskets today and thought I figured things out at first. I found that the last time I put the no. 1 header pipe on, it slipped in on top of the header bolt washer rather than under it. So the washer was trapped between the head and the header preventing a good gasket seal. Everything is black under there so until I hit it with a light it wasn't evident. Self-induced error and explains the large carbon tracks on the lower side of the gasket on that cylinder. Took care of most of the noticeable tick but it still have a lot of what seems to be valve train rattle. May be time to check with the builder and see what they think.