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Does anyone have a recommendation on cold valve lash settings for a '48 288 (solid lifters)?

I know the recommendation is to adjust the lash on a warm engine, but I don't see myself finishing a valve adjustment in the amount of time it would take for the engine to significantly cool, and the idea of reassembling to rewarm seems a bit odd. Plus I would like to 'take all day' crawling around on cardboard without getting a lot of oil on the cardboard.

For the '48 288 there is the original lash recommendation and then a later Packard recommendation to help reduce 'valve clatter' . . . they reduced the lash about 0.002 on both valves (see Service Counselor 22-12). The 'new' recommendation is 0.006 for the intake, and 0.008 for the exhaust.

I searched the internet on this subject and there is plenty of advice for overhead valve engines with all of the possible combinations of block, head, and pushrod material choices, plus rocker arm ratio. As a result the delta valve lash between cold and hot varies quite a bit. The question I'm asking should be based only on the differential temperature between the block (coolant temperature) and the valve, plus the valve length. I did a quick calculation and convinced myself that we may be talking about 0.002 clearance reduction for the exhaust and less for the intake . . . perhaps just set the original clearance (pre- SC22-12) cold and 'call it a day'.

I would like to hear from those that have some 'first hand' experience in this area.

dp

When I make a preliminary adjustment on the engine stand I use .007 intake and .011 exhaust.

After the engine is in the car I redo the adjustment with the the engine fully warm and running. Although it is not my favorite entertainment, it really is not that hard after one removes the inner fender panel and the heat shield on the fuel pump. At idle speeds there is hardly any oil splash to speak of. These later engines only require two wrenches to adjust which is much easier.

The hot and running adjustment takes care of many variables (ex: hot spots, growth in dia of the valve head etc.) all at one time and gives a long lasting result.

Good Morning Dave and Ross...Our 1949 288 Deluxe, Miss Prudence, had her valve lash set warm, but not running at 0.007 and 0.010 which was recommended in the Packard manual and the old Motors manual that I have. This was done about four and one half years ago and she starts well, runs well, and does not make any noise...Ross and I have ours set pretty close to the same and so you should be happy with the result. Enjoy your day. Ernie

Thanks for the information Ross.

If I might be allowed a 'follow-up' question; after setting the cold values, did the lifters need any significant adjustment when the engine was warm, and do you adjust to the original values (8 & 10) or SC 22-12 values ( 6 & 8)?

dp

Oddly enough, some need more adjustment than others, which is why I am a fan of doing it hot and running. I do use 7 and 10 as recommended for the later engines. I usually go for a nice snug pull on the feeler gage for the intakes, and pretty loose on the exhausts.