I have finally gotten around to trying to solve for a front bank oil leak at the O ring cam seal on my 1988 3.2. While I have the cam cover off, I am checking the valve clearances. The car has about 78,000km. Valves were checked and adjusted before I purchased the car at about 30,000km. The upper valves, the intakes are all at about .19mm, while the lower exhaust valves are all consistent at .28mm. I would also have expected some variation between the various valves, but they are consistent. I am reading clearances for the 3.2 should be .35 to .40mm on the exhaust, and .20 to .25mm in the intakes. Would the valve wear noted be about right for 50,000km of wear, assuming the car was set within spec at its 30,000km service in the first instance? So mine are a bit tight, and I am surprised the intakes are more off spec than the exhausts which I thought would wear faster. I am tempted to leave things be, as I am not grossly off spec. How much off spec would one normally consider is too off spec before doing the fuller reshimming of what in my case would be all valves? How tight before I am asking for trouble? I know the correct answer will be to get back into spec, but is there some real world practice that on this that anyone can share?
Don't follow you here -- your intakes are barely off (.19 mm vs a spec of .20 mm minimum). The exhausts could use a reset, but after 48,000 km, I'd just say "that's normal-ish" and is why there's a spec to check/reset them after about that mileage interval (IME exhaust valves tend to get tighter with use while the intakes stay more stable, but can get larger if a lot of carbon build-up occurs). Just as a side note, those specs are for the valve clearances at the start of the next mileage interval -- they are not the ranges that the valve clearances absolutely must remain in at all time during the next mileage interval (i.e., some change over the mileage interval is expected by the Designers).
Valve clearances never change that consistently. 2 valve and 4 valve engines had different specifications and many conflate them. I suspect yours were set incorrectly.
The actual clearances were mostly the same Very helpful, thank you. My message was confused, I originally wrote it thinking the .35 to .4mm was the spec for both intake and exhaust, all old threads focus on the exhaust valves clearances. I then altered the note with the correct spec for the both intake and exhauist, so sorry for the confusion. So yes the exhausts appeared to be wearing more than the intakes as one might expect. I can't be sure what the exhausts were originally set at, it is possible they were set incorrectly to the old 2 valve spec when the original dealer 30km service was done many years ago.
Very possible, but it's even more messed up than that . The 308QV OMs and 328 OMs show an exhaust spec at .35 - .40 mm, but the 308QV/328 WSM has the exhaust spec as .30 - .35 mm in the text on page B32, but .35-.40 mm in the figure on page B32. Easy to see how a Mechanic might read the text (first) and then not notice that the figure value is different.
The car 30,000km major was done in Switzerland. I understand the tighter exhaust valve spec was for the Euro models, and the larger spec for the cars with cats. Perhaps the mechanic used Euro spec on a cat equipped Swiss market car.
I think that distinction (for with cats vs without cats) is only on the 2-valve V8s. On all of the 4-valve V8s (even the catless euros) they used the larger exhaust clearance spec-- but still very possible a "euro" mechanic just misapplied the euro exhaust specs from a 2V era.
