Vavle spring replacment question #2

[Dan Pepper]

In preparation for changing the valve spings on my '66 L36, I pumped 80lbs of air into #1 cyl. to get the valves to seal. I could clearly hear air leaking out of the valves - sounded like exhuast valve leakage since I cracked the seal on both so I could hear the difference between the air coming out of the in take and air escaping via the exhuast maifold.

Just for comparison, I applied 80 lbs. pressure to all the other cyls on the left bank (1,3,5,&7) and heard pretty much the same sound. Should I hear any air escaping during this procedure? And if no, could this mean burnt valves on all 4 cyls? (haven't tried this on even cyls yet).

Prior to this, as part of diagnosing the broken valve spring problem, I did a compression test that yielded 70-80lbs pressure for all of those cyls. I didn't do a leakdown test though.

Note that after a few raps on the valve spring removal tool on #1 exhaust valve and #3 exhaust valve, I was able to crack the valve retainers loose without loosing pressure, so I'm confident I could replace all of the springs using the regular procedure.

Is it ime for a valve job? Or is some air pressure leakage during this procedure normal?

[Clem Z.]

Re: Vavle spring replacment question #2

you will hear air going past the rings into the oil pan and if you have a leak past the exhaust valve it means there is carbon under the valve seat. with the air still in the cly hit the top of the exhaust valve with a dead blow hammer and the valve will smack against the seat and seal. the other problem with the lifter is if you can not find the push rod seat it can cause problems because it can be anywhere and you must find it. you can put it back in the lifter and install new snap rings and i would do this to all the lifters. you will have to at least pull the intake if not the oil pan to find the lifter seat. any good auto parts can supply the new snap rings. dan you are not the first one this has happened to BUT you must find that push rod seat. i am now off to carlise so good luck.

[Werner R.]

Re: Vavle spring replacment question #2

clem
what is a push rod seat and how did you know from dan's post that he lost it. i have re-read the post several times and i don't see anything about a pushrod seat.
werner

[Werner R.]

Re: Vavle spring replacment question #2

clem
i jsut read the post where dan said he dropped it. is the push rod seat the same as a tappet??
werner

[Werner R.]

Re: Vavle spring replacment question #2

me again
do you think that the problem with the seat clip is related to his broken spring, either as cause or effect??

[John H.]

Re: Vavle spring replacment question #2

Werner -

Nope, the pushrod seat is an internal part of the lifter, retained by a spring clip. "Tappet" and "lifter" are different words for the same part - the pushrod seat is an internal component of either.

[roy braatz]

Re: Vavle spring replacment question #2

I would replace the broken spring, put every thing back, then at 3000 rpm ,spray water down the carb just keeping the engine runing which will clean out all the carbon build up around the valves and pistons tops, then check compression again.I do this once a year to keep carbon from building up around the valves.IT WORKS.

[Brian Monticello]

Re: Vavle spring replacment question #2

How much water and at what rate do you deliver it?
Thanks
Brian

[roy braatz]

Re: Vavle spring replacment question #2

Engine runing at around 3000 rpm I spray water down the carb for about one minute at a rate were the engine is stumbling to run . (Get the engine first up to runing Temp.)Do you remenber years ago they offered water injection for all cars, an after market to increase HP and to eliminate ping, it also kept carbon build up off the pistons.It worked great when using low actane gas.(no ping)