Damage from bad lash?

[dunc2027]

1974 super convertible, my first car from before 1995. Fun stuff. Bought it in March, ran it around quite a bit, but knew I had plenty to fix. Low on power since purchase, can't keep 50mph uphill even at 3000rpm. I've never messed with any of this stuff, but it came with a Clymer manual, so I started reading. Began a tune up last week and started with valve lash. As found, in thousandths:
#1 EX8 IN4.5
#2 EX0 IN19
#3 EX0 IN6
#4 EX0 IN3.5
That's right, I couldn't get my snallest feeler .002 in several of them. Yikes.

Should I expect damage to the camshaft or pushrods or whatnot for driving pretty hard for 500mi?

[FreeBug]

The biggest risk with no lash on exhaust is burning a valve. Like cutting off a slice of pie, and there will be massive leakage and noise. A leak-down test could help clear things up.

Having said that, even if it's all airtight, there's the fact that the exhaust valves might have recessed into the seats, or worse, started stretching. What is the mileage on the heads?

[oprn]

Aluminum pushrods or steel? Checked hot or cold?
_________________
We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)

[Dougy Dee]

No lash on exhaust could also mean valve is stretching or seats are pounding/dropping into heads.

[dunc2027]

I think it's the original hardware. Car only has 29k on the odometer. Lash was measured stone cold. I also did a cold compression check after.
#134 were real close to 120 and #2 was 140.

[Ohio Tom]

Just re-adjust and keep an eye on them.
Normal for them to move a bit. that's why we need to check them so often.

[dunc2027]

I'd be flad if it's no big deal. Thanks for the replies.

In general, is there ever a reason to pull the heads EXCEPT to investigate an observed problem? It's not something that should be done as a checkup or part of any preventative maintenance?

The rust on the studs scare me anyway.....

[stevebaz]

Adjust the lash fowling the proper procedure. then do a compression test. then wait a month and do it again checking as found and re adjusted. check compression before and after adjusting valves. keep a log for three months note how many miles between checks and adjustments. this should plot a course of what is going on inside. your engine as bought means nothing as you don't know the skill of previous mechanics doing the work, so don't jump to conclusions on what may or may not be wrong until you have logged some hours on it. if it was really bad you would know it. relax watch oil consumption valve lash settings and compression pressure and how the plugs look and write it down in a log until your happy knowing what is going on. Hot and cold oil pressure is a good one to note too but that means adding a gauge.

goot to check flywheel to case end play while you have the engine out.

[dunc2027]

Sorry for the late response, late nights at work this week. Thanks for the advice!

I ended up pulling the motor to do oil cooler seals, and it's kind of snowballing from there. I got a "rebuild" gasket set and new pushrod tubes, so I'll probably replace everything I can without taking the case halves apart. I have new head studs and nuts as well, so I'll pull the heads and inspect and document what I find. As long as I don't find anything catastrophically broken I'll probably put it all back together, give it a tune, and hope it runs a little better than before.

I'm learning what some of the bits and pieces do, and what's missing. The EGR filter broke off some time ago, and the exhaust tap is plugged, so if the EGR is operable it would make the motor significantly lean when it opens, right? Instead of pulling inert gas from the exhaust it would be pulling ambient air with oxygen aplenty. I will probably ditch the thing and cut some sheet metal to block off the EGR port on the intake manifold.

Speaking of the manifold, it has two riser tubes per side. The aftermarket muffler that came NIB with the car has provisions for only one. The previous owner either bought the wrong one or had plans to change out the manifold, I guess.

Why does it have two per side? I can't find any pictures of them online, and the VW shop guy has seen only a few in his years. I guess it was a California emissions thing? (It's a 1974, sold new in Cali. It came with the original service booklet with 40 years of notations. I guess I'll keep the factory muffler. It's a little bent, but doesn't hurt anything.

[FreeBug]

Twin manifold heat was a cold climate thing...

[oprn]

I have never seen dual heat risers in Canada. Nor have I seen an EGR system on a Beetle, only the type 4 Bus engines but there may have been a few in the last year or two of production. I think the OP is correct, the dual heat risers is a California emissions thing.
_________________
We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)

[vdubrookie]

What EGR Valve?