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View Full Version : I think I found my tick-ticky - burned valve??



Robin-535im
12-05-2006, 02:40 PM
Checked on them valves again last night. Tick was getting loud enough that I didn't want to drive it, and strangely I could feel the tick in the exhaust...

Bone cold and I set them all to 0.012 inches. Bump starter is soooooo cool. For all you die-hards who haven't built a momentary-on switch to connect pins 11 and 14, you're really missing out. I used speaker wire and a lightswitch wrapped in electrical tape... king of the garage rats, yes.

Anywho - exhaust valve #2 needed the eccentric rotated WAY down, much farther than the others. I checked and re-checked, but that's what it needed to get the clearance to 12, it was way out when I opened her up.

Rocker arm foot pad looks a little smaller than the others, but I didn't have calipers to measure it. Can't think of why this one should be so far out of whack.

Would a burned valve do this? I suppose I could pull the whole assy and measure each part to see what is off... but that is a lot of work. Runs fine and no outstanding tick, just a lot of little ticks that have similar intensities.

Nice to have her back on the road. I've been driving the old pickup for the past 2 weeks. Fun in an old-school redneck sort of way, but no where near the fun of the e34.

Blitzkrieg Bob
12-05-2006, 02:49 PM
sounds like the ecentric was not tightened the last time it was adjusted and rolled out of spec.

A burned valve would not go away after adjusting the valves, it would stay with a miss, back firing, rough running etc.

632 Regal
12-05-2006, 04:51 PM
burned valves close up the clearance.

632 Regal
12-05-2006, 04:52 PM
burned valves close up the clearance. Either Bob is right or you have a LOT of wear going on. was the excentric loose when you adjusted it?

Robin-535im
12-05-2006, 07:25 PM
burned valves close up the clearance. Either Bob is right or you have a LOT of wear going on. was the excentric loose when you adjusted it?
It was snug, but the gap was big. The eccentrics have a little hole in them to help turn them for adjustment, usually the hole is about at 11 o clock when viewed from the front of the car, this one had to go rotate all the way back to 9 o clock or so to get the gap right.

I sure don't recall it having to turn that far in before, though when I opened it up it was already turned down quite a bit. I sure would have thought I'd have remembered having to turn it all that way before as it's abnormal. Then again I'm the only one who has touched the car in the past 2 years so if it was snug and in that position, I'm the one who did it. Hmmmm...

DaveVoorhis
12-05-2006, 07:52 PM
Maybe measure the camshaft lobe (not the adjuster -- the camshaft itself) with calipers and compare it to some others, in case it's worn.

ricola
12-05-2006, 08:07 PM
I agree it sounds like a flat cam lobe. I had that happen on an beater E28 once. I drove the car 50,000 like that.

Robin-535im
12-08-2006, 04:46 PM
I agree it sounds like a flat cam lobe. I had that happen on an beater E28 once. I drove the car 50,000 like that.

The cam lobe doesn't usually wear on the heel side though... but it is a regrind so maybe it was ground too much on the heel.

Pretty sure the oil sprayer is working, as there is always oil in the nooks and crannies at both ends, and I haven't really noticed excess wear.