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JoeHall
05-28-2018, 06:14 PM
Since getting the 63GT back on the road a month ago, had began to notice a lope at idle. Today, feeling the lope, I made a note to self: check the maintenance log to see when the valves were last adjusted. Later looking at the log, sure enough, it has been about 15,300 miles. That is a lot further than I usually get out of the 63GT, since it still has OEM valve seats. It usually goes around 12,000 or so between adjustments. The 62GT, with hardened exhaust seats, usually goes around 16,000. I should check the maintenance log more often, but the idle lope always serves as a reminder anyway.

So, I definitely need to get round-2-it with the 63GT's valves. Probably this weekend.

62champ
05-28-2018, 07:33 PM
Joe - are you a cold adjuster or a operating temp adjuster?

JoeHall
05-28-2018, 07:47 PM
Joe - are you a cold adjuster or a operating temp adjuster?

Too much hassle when hot, so I make it easy, and adjust them either cold or warm. I set #1 on TDC, then adjust half of them; rotate the crank 360 to #1 TDC again, then adjust the other half of them. I also set them real loose. Looking at the maintenance log, I set them at .029" last time. They will click lightly, but then quiet down in a few thousand miles.

I expect the exhausts to be hammered down to around .010" when I adjust them this weekend. But the intakes probably will all still above .025".

christophe
05-29-2018, 02:35 AM
Joe, have you already installed the red Bosch ignition coil on your 56J? I was wondering about the results.

swvalcon
05-29-2018, 08:43 AM
Joe i would guess if you only need to adjust the exhausts they are pulling into the head. I've seen exhaust valves on small block chevs without hard seats pull in so far to where they are below the head around them.

JoeHall
05-29-2018, 10:02 AM
Joe i would guess if you only need to adjust the exhausts they are pulling into the head. I've seen exhaust valves on small block chevs without hard seats pull in so far to where they are below the head around them.

True, but with the Stude's relatively mild springs and cam, everything will wear at about the same rate. By the time the valves have receded too far in the heads, it will be time for a rebuild anyway. My experience is, about every 100,000 miles they need going through. I always install hardened exhaust seats, but only if disassembling the motor anyway. I'd never remove the heads just to install hardened seats. To me, adjusting valves is a PITA, but necessary with old Studes. So I try to keep it as painless as possible, with hardened seats, and running adjusting them a little loose. If I had to adjust them every 5000 miles, per the Shop Manual, I'd probably just get away from Studes. LOL

lumpy
05-31-2018, 09:35 PM
In my opinion ,the sound of a mechanical cam is something to behold , and adjusting valves is kind of an old school zen experience ......Bring it in the shop , adjust the valves, check the timing, read the plugs, check the carb for full throttle....And hit the street Sat night for a little clandestine FUN ! :rolleyes: But alas that was the old days.

JoeHall
06-01-2018, 10:55 AM
Well I am off work today, so need to get out into the garage and get those valves adjusted. On both of our GTs, the valve covers are buried beneath lots of stuff, not usually found on GTs: mainly hoses, wires, bracketry and components from AC, aux heater, HFI, cruise control, etc.. On the passenger side especially, it is a chore just getting the valve cover off.

If rebuilding another 259/289, I'd seriously consider the above, hydraulic lifter setup, mentioned by Jack V.

JoeHall
06-01-2018, 04:33 PM
Start to finish, today's valve adjustment took 4 1/2 to 5 hours. I did a few other things while at it, but mostly the time was spent on the valve adjustment job. As mentioned above, its been over 15,000 miles since the last adjustment, so I fully expected the exhausts to be around .010". That is what my maintenance log says they were down to, at the last prior adjustment, after only about 12,000 miles. As noted, intake & exhausts were all set to .029" cold, over 15,000 miles ago.

Today, the clearances (cold) were as follows: INTAKES were all between .025" and .028", so I left them alone. EXHAUSTS were between .022" and .027", except #7, which was .012". All exhausts were reset to .029" cold.

Not sure why the exhausts did not close up as much this time, but can only guess the seats are, indeed, the hardened type. I bought the car six years ago with a cloverleaf motor already installed, with an estimated 5000 miles on it. Back then, I pulled the heads to look everything over and install new gaskets. But I did not check, and really do not know whether hardened seats were installed. However, today's clearances strongly indicate they are hardened.

The smooth idle has returned, so I guess the operation was a success.

63looks59
06-03-2018, 08:46 PM
a Fast method is to use a remote starter--- hit it very briefly, and work that feeler gauge back and forth for the 1.5 seconds that the engine rotates----do the adjust and move on....so its a " cold method with engine briefly moving " This way oil never pumps all over the place....you end up with a good job

63looks59
06-03-2018, 08:47 PM
The top end " chews" on the feeler a little bit, but doesn't hurt ot