Intermitentent Vavle Tick

[jswatson0917]

My '79 CJ7 with a AMC 304 and three speed has an engine tick that sounds to me like a valve ticking. It happens when I first start the Jeep after it has been sitting for long periods(Overnight) but it goes away after the engine warms up. Today when I jumped on the freeway it starting ticking pretty loud. I was close to home so I kept driving. After I jumped off the high way I wanted to get the jeep home and my house is at the bottom of the hill from the freeway I put the Jeep in Nutral and coasted down the hill after a half a minute with the engine idling the ticking had stopped. I drove around for ten more minutes the ticking started up again I sped up a little and put it in nutural again after a half a minute or so it stopped again. All of this happens on the left side of the engine. Could it be possilble that my oil pump it going bad or the left side line may be clogged? or am I going to need a valve job? Thaks for any assistance you may have.

 

[CJ]

Sounds to me like you have a lifter beginning to fail. Especially since it ticks after sitting for a while, it lost the pump up it had when shut down.

 

[xj287]

Moth likely your loosing a lifter, but given the year it's also quite possible the oil pick up on the pump may be plugged with sludge, so it may be worth while to drop the pan and make sure everything is clean down there while your at it.

Also VERY IMPORTANT! remember your engine is NOT COMPATIBLE with the new GF-4 motor oils on the market today make sure you are using a CF rated (or the newer CJ4 ) motor oil. I have a pile of lifters and cams behind my shop that were runined from using the wrong oil.

 

[rushpowersystems]

Only when cold? Check your exhaust manifold, many times leaks sound like a lifter tick.

 

[IOPort51]

If you put a vacuum guage on the intake mnifold I think it will tell you if you have a failing lifter.

There is also the possibility of piston slap.It is getting more and more common. I understand it has something to do with using unleadded fuel.
It goes away when youwarm up

 

[jswatson0917]

Thanks for the info I will look in to the sludge build up and the failing lifter.

 

[Old Dog]

Also VERY IMPORTANT! remember your engine is NOT COMPATIBLE with the new GF-4 motor oils on the market today make sure you are using a CF rated (or the newer CJ4 ) motor oil. I have a pile of lifters and cams behind my shop that were runined from using the wrong oil.

I use Shell Rotella in mine

 

[xj287]

Rottella T 10w30 is the only oil I use at my shop, great stuff! And it's actualy recomened by Melling, clevite, and sealed power for use in all flat tappet and L-head engines.

 

[jswatson0917]

I was always taught that Shell Motor oil was the worst to use due to the sluge build up that it creates :dunno:

 

[xj287]

that is true with SAE30 non deturgent....but a multi-viscosity oil like 10w30 has a strong detugent package to deal with the sludge built up that you'd get with any oil (even synthetics). The reason that shell rottela is prefured over others, is because of it's higher zink and phophate leval which our older flat tappet engines NEED. But, Mobil Delvac 1300, and Dela 500 are very well thought of also.

 

[jswatson0917]

Got it thanks