Camshaft Thrust Plunger Grease

[Mark from Indy]

At the risk of that guy's dog getting on me for repairing my car - here goes.....

Investigating a knock in the front, looked at the timing gear and visually all seems well. Reading about the plunger and the notation in almost all the catalogs about - grease it or it makes a heck of a noise - I put some regular wheel bearing grease on it before assembly. The noise is right where the pin is so that was what I was hoping it might be and breathed a sigh of relief when the gear looked OK.
Motor ran quiet as a mouse for a hour or so and then it started that noise up gain. Where this is leading is, isn't this area in a kind of oil bath, such that greasing the pin becomes moot after a while if it is hot oiled and dissolves? Is there a secret grease to use that might be more "clingy" ?

A side note which I'm sure others have seen - looks like someone took a Persuader Bar to get the Giant nut on and off. Don't know about you, but my torque wrench doesn't read right when used as a sledge

Thanks
Mark

 

[Patrick L.]

OK, so I'm assuming you didn't replace the cam gear ? Did you measure it ? The clearance between the teeth should be about .004-.006". It you can fit a .010" feeler strip between them then they will argue with each other and make noise.
Oil should be feed to the gears and it should be noticeable.
How did the plunger, spring and end of cam look ? If the little cross/X was worn off the plunger then its defective. The spring can become compressed. New springs are available or a 'shim' can be installed behind it.
I don't you really think you need to use a torque wrench on the cam gear. TIGHT is good[which is about 100#]. From your post it sounds as if it was last changed with a hammer and chisel, kinda normal. But, new nuts are available today.

 

[James Rogers]

I hate to be the bearer of bad news but I don't think your problem is the plunger. I find most times when the plunger won't hold the cam back it is because of tightness somewhere else. Check the distributor first for dry ,tight bushings. If that is not the problem you may have an oil pump problem. The reason the cam moves forward and snaps back is when something won't turn like it should, the cam tries to climb the drive gear and moves forward till the stiffness is overcome which allows it to snap back against the block causing a knock.

 

[Tom Wesenberg]

A dry plunger will make a squeal, but a loose two piece timing gear will make a knock or rattle.
Any chance you have a loose 2 piece cam gear?

 

[H. L. Chauvin]

Hi Mark,

[QUOTE Motor ran quiet as a mouse for a hour or so and then it started that noise up gain. QUOTE]

1. The above quote appears to be a mystery of some sorts because metal contracts when cold & expands at operating temperature; hence, sometimes engine noises at start ups tend to lessen after the engine is warm, naturally depending upon where the noise originated.

2. Did you try to tighten the cam gear?

3. Even though this may not be the case, the symptoms in paragraph 1. above sounds like one tightned the cam nut a little, it ran fine for an hour, & the cam's thrust accompained by engine vibration loosened the cam nut a little, the cam gear started vibrating, & now the noise is emanating from the cam gear area as a result of a loose gear contact, accompanied by cam shaft thrust noises.

4. Unknown to many, with all due respect for the reasoning that we have as humans, this sounds like something that Buster-T could help us with his instinctive mind mainly because a few people like his master who has a smart dog, can learn from their dogs that rather than using one's human mind of reason when thinking, many problems can be resolved by thinking like a dog -- I personally never saw a dog make a poor judgement call -- sometimes, dog decisions are helpful -- Bill W. may want to add an instinctive canine remedy.

 

[Brentwood Bob]

Along the lines of the advice already given, The distributor can be installed too snugly, and will bind up giving a definite knock. Even a binding joint in the 2 piece shaft can contribute. Did you install any other parts before you noticed the knock for the first time. A basic rule that helped me trouble shoot in the past is to change one thing at a time. And then evaluate for any change. Otherwise we are using the shotgun approach versus the rifle. Bob

 

[Del in NE Ohio]

I fought the same problem.. turned out to be the two piece fiber/steel gear. Visually i couldn't see anything. But when I changed it, problem solved.