Tapping sound in motor

[Bratcher4079]

I have an 89 Valiant VIP that I just aquired. When I bought the boat it ran great. After sitting two weeks when I sarted the boat there was an immediate tapping/clicking sound coming from on top of the intake manifold. This sound wasnt present when I purchased the boat. Could this be a stuck lifter or something in the rocker arm? What is the best way to diagnose this type of issue. I used a stethescope to try to better locate the sound and all I could narrow it down to was the top of the manifold area. The sound is definately coming from inside the motor. Any ideas?

 

[bruceb58]

Re: Tapping sound in motor

I may get blasted for this and I am normally totally against the use of "snake oils" but I have freed up sticky lifters by putting a qt of ATF in the crankcase. Once it has quieted down, I change the oil.

 

[bubbajckson]

Re: Tapping sound in motor

As an ASE Master tech for many years I can only say that I never heard of ATF used this way as it is of much lower viscosity than motor oil. STP and the like are VI increasing additives used to quiet valve-train noises. But if it works, who am I to knock it. That being said... what motor are you dealing with here and I would feel safer offering advise.

 

[jbetzelb]

Re: Tapping sound in motor

ATF has a lot of cleaning agent in it. Old schoolers used it (and it does work) to clean build up out of engines.

 

[HT32BSX115]

Re: Tapping sound in motor

ATF has a lot of cleaning agent in it. Old schoolers used it (and it does work) to clean build up out of engines.

ATF does NOT have "cleaning agent" in it (any more than any other hydraulic fluid)
It is a hydraulic fluid. It's also a light oil You could get the same "cleaning" (solvent) effect using diesel fuel, kerosene or even gasoline.

BUT doing this you also run the risk of breaking loose particles in the engine.

If they break loose prior to being picked up by the oil pump, they'll (YOU HOPE) be stopped by the oil pick-up screen or filter.

If they break loose AFTER the filter (I.E. in an oil passage going to a bearing), then you run the risk of spinning a bearing.

Cross your fingers!


Rick

 

[Scott Danforth]

Re: Tapping sound in motor

pull the valve covers and take a look. if the inside of the valve cover area is full of gunk, then running seafoam, ATF or diesel in the engine will loosten all the crap up and either plug up your pump screen thus starving the engine of oil, or plug up a bearing lube point which will then starve a bearing leading to a trashed bearing.

if the inside of the valve cover area looks clean, then try any of your favorite engine treatments to loosten up a ticking lifter.

 

[bruceb58]

Re: Tapping sound in motor

ATF does NOT have "cleaning agent" in it (any more than any other hydraulic fluid

I believe ATF contains dispersants which act similar to a detergent.

Again, I am not a believer in "snake oils". YMMV

 

[HT32BSX115]

Re: Tapping sound in motor

I believe ATF contains dispersants which act similar to a detergent.

Yup. Actually any "detergent" could probably be accurately called a dispersant. (but any solvent can be called the same thing too depending on where it's used) most oils (motor, hydraulic, gear, etc) are also "spec'd" with an ASTM standard for "detergency". Whether one "detergent" for one is "better" in another application is probably up for "grabs".

Detergents in motor oils are specifically designed to keep combustion products in suspension (like soot in diesels) where detergents in gear or hydraulic oils are aimed at other than combustion products. (which is sort of why you wouldn't want to use ATF or gear oil in your crankcase!!) BUT there are cases where ATF is used in gear boxes (ZF manual transmissions for one)

Any of them might work. (for what the OP wanted to do) But I wouldn't do it.

Again, I am not a believer in "snake oils". YMMV

Yeah! neither am I!!

 

[Bratcher4079]

Re: Tapping sound in motor

THe motor is a GM 4.3l V6.

 

[HT32BSX115]

Re: Tapping sound in motor

THe motor is a GM 4.3l V6.

Just pull the valvecover on the noisy side and look.......... turn the engine with a wrench until each cyl is on TDC and you'll find culprit.

 

[Silvertip]

Re: Tapping sound in motor

There are a couple of products that have proven effective for many decades and are still available. Back in the late 40's and early 50's when hydraulic valve lifters first appeared, many cars didn't have oil filters and oils did not have the detergents required to keep things clean and unvarnished. It didn't take long to determine the filter was necessary as those lifters would begin to clatter. Marvel Mystery Oil and Rislone were introduced and since I'm old enough to have seen this stuff work and used it myself there is nothing wrong with exchanging one quart of oil with a quart of either of these products. I prefer Rislone. Rislone is a 5 weight oil with extremely high detergency content. I've used it in engines after a rebuild were the engine had been fried to a crisp and left the brown varnish on the inside of aluminum valve/cam covers. Even lacquer thinner wouldn't touch it. In 500 miles Rislone makes those covers (and very likely in other places you can't see) look like new. However, with todays oils there should not be a need for any of these additives. Sticky valves are a sign of moisture/water intrusion or simply lack of maintenance. There is a chance a rocker arm stud or nut has worked loose or that a rocker arm or pivot ball has worn. But then that doesn't happen sitting at the dock or on a trailer.

 

[Bratcher4079]

Re: Tapping sound in motor

I have another issue that I just noticed. I have a grayish colored liquis comning out of the fuel pump block off plate on the engine block. It begins to seep out after about thirty minutes when running on muffs. I looked in the valve cover with the oil fill opening and found moisture on the rocker arms that I could see. I also saw the same fluid on the lifter that I could see with a flash light. The area of the oil filler was spotless and so was the oil cap. Does this sound like a head gasket. The oil on the dipstick looks like there isn't any moisture on it.

 

[bubbajckson]

Re: Tapping sound in motor

Dipstick may show overfilled if water or coolant is leaking into the crankcase. Drain the oil and check for water/coolant content before running it again! Condensation can cause this to a very limited degree but it should be VERY limited and definately not visible on internal parts. It sounds likely that you have a bigger issue than just a leak in the pump block-off plate. This is probably why you have lifter noise as well! Could be intake or head gasket leak, next step will be compression tests on cylinders, maybe intake leak if you had no water out the mufflers and engine ran good. Like the man said....cross your fingers.

 

[projo198]

Re: Tapping sound in motor

Amsoil makes a cleaner you run in your existing oil right before an oil change that is supposed to do a good job of cleaning your motor out.

I have also gotten in teh habit of adding a little Marvel's Mystery Oil to my gas, even in my touchy Nissan 300ZX. It can be used as an oil additive too.