Identify engine sound?

[Roald P.]

Re: Identify engine sound?

Roald:

The pitch and sound of the noise does not sound like a lifter or a rod bearing. It sounds more like an AC compressor (or smog equipment which you say is not there). Does the car have AC? If so, remove the belt and run the engine and see if the noise disappears. It's worth a try.

Paul

Yes it has AC but the belt was removed many years ago. I think the noise could be because left side of all of the counterweights on the crank is riding against the main caps? see the blank spots in the red rings on the picture below

[Roald P.]

Re: Identify engine sound?

before going through all the money and labor for a rebuild, find the source of the noise. If the engine runs good and only uses a modest amount of oil it may be fine.

Why do you think it needs to be rebuilt, slow down?

Will I not risk damaging the crank (and other components) more if I continue to run it with all the metal that has been in the oil?

[Timothy B.]

Re: Identify engine sound?

Roald, From your picture, the metal in your oil pan does not seem that bad. Has the motor ever been rebuilt?? How much thrust does the crankshaft have forward and back, .20 or .002, If it's .20 that's approx 3/16". If it's .002 then it is within spec not to exceed .006

[Roald P.]

Re: Identify engine sound?

Roald, From your picture, the metal in your oil pan does not seem that bad. Has the motor ever been rebuilt?? How much thrust does the crankshaft have forward and back, .20 or .002, If it's .20 that's approx 3/16". If it's .002 then it is within spec not to exceed .006

[David D.]

Re: Identify engine sound?

Roald, I would check the valve guides in the head. Sounds like a worn intake guide, valve stem, or both, IMO. Dave

[John M.]

Re: Identify engine sound?

I was always told that the fine gray goo is lead deposits from leaded gas. Every old motor I have taken apart has had this, I would not be concerned.

I would be concerned about .200" end play. Should be more like .002-.005" Also what's up with the shiny counterweights on the crank? They should be brown like everything else inside. Something was rubbing them (side of the rods?).

Drop the rear cap and let's take a look at the the thrust bearing. BTW, usually a thrust (excessive endplay) knock will go away when you depress the clutch.

Will I not risk damaging the crank (and other components) more if I continue to run it with all the metal that has been in the oil?

[Roald P.]

Re: Identify engine sound?

I was always told that the fine gray goo is lead deposits from leaded gas. Every old motor I have taken apart has had this, I would not be concerned.

I would be concerned about .200" end play. Should be more like .002-.005" Also what's up with the shiny counterweights on the crank? They should be brown like everything else inside. Something was rubbing them (side of the rods?).

Drop the rear cap and let's take a look at the the thrust bearing. BTW, usually a thrust (excessive endplay) knock will go away when you depress the clutch.

The counterweights are rubbing on the main caps. Its an auto car. I will drop the rear cap and then return. It would be nice if its just lead deposits

[Roald P.]

Re: Identify engine sound?

I was always told that the fine gray goo is lead deposits from leaded gas. Every old motor I have taken apart has had this, I would not be concerned.

I would be concerned about .200" end play. Should be more like .002-.005" Also what's up with the shiny counterweights on the crank? They should be brown like everything else inside. Something was rubbing them (side of the rods?).

Drop the rear cap and let's take a look at the the thrust bearing. BTW, usually a thrust (excessive endplay) knock will go away when you depress the clutch.

I got the rear cap off, the thrust bearing has worn a groove in the crank, I'll guess its between 0.03-0.04 inches deep. I also measured the crankshaft endplay a little more precisely, its 0.107 inches.

Is it possible to repair the crank?





Main cap

[Mike M.]

Re: Identify engine sound?

Good morning, Roald
The silver non-magnetic content in your goo is risidual bearing wear (Aluminum), some of this is typical, yours seems excessive confirmed by your bearing pics.
Even though your crank "appears" to be OK, it may not be and your bearings definitely are not. It is normal for them to develop wear and heat patterns, no offense, but, actually, they look quite nasty.
Having opened it up to this point, if it were my engine, Iwould complete the rebuild.
Better than picking up the pieces later.
HaND

[Richard T.]

Re: Identify engine sound?

Ron: Looking at your very good pictures I would agree with the other guys on your engine maybe needing a rebuild or overhaul. You would have to pull the engine out of the car to remove the crank. I would not go further on the cap removal because these parts have to go back the way your engine was made when new. The end lobe spots on the crank are machined. The noise would be extreme knocking if the crank was hitting the cap and get louder when the idle was raised. I would replace the cap and pull the head to check the bores for ware if you feel a ridge at the top of the bores it is time for a rebuild. If you decide not to this now; replace the end seals and reinstall the pan. Replace the oil, pull the plugs and do a compression check. If the check is with in speck pull your belts and start the motor to see if you hear the noise. If you hear the noise reinstall the belts and scope your heads and block to find out where the noise is coming from. This procedure will give you a good idea on what to do about your motor and the cost to repair it.

[John S.]

Re: Identify engine sound?

Roald,
At the risk of really opening up a can of worms on this thread, I am jumping in. First off, I did not see where you listed how many miles were on the car. Regardless, I agree with many of the other posts that you should rebuild your engine. Far to much bearing metal in the pan for my taste. You do not know where it has gotten to, especially if the oil filter became plugged. If it was the oil was eventually routed around the filter and will have gone every where. Here is where I am going to get in trouble. Pennzoil was mentioned in an earlier post. It is one of the most popular oils in the states. Probably lubricates very well also. But, to my understanding it is a perifin based oil And over time will build up a sludge in your motor that would make any Corvette enthusiast sick to his stomach. My dad was a mechanic for some 40 years and he told me when I started driving and working on car he would hang me by my b***s if he ever caught me using Pennzoil or Quaker State oil in any car. There it is guys. Especially interested in what Duke has to say about this as from his numerous posts he seems extremely knowledgeable about these things.
John

[Roald P.]

Re: Identify engine sound?

...they look quite nasty.
Having opened it up to this point, if it were my engine, Iwould complete the rebuild.
Better than picking up the pieces later.
HaND

I agree. The thrust bearing in the very highmilage '65 327 smallblock I pulled out of my other '68 vette didnt even look half this bad

...The noise would be extreme knocking if the crank was hitting the cap and get louder when the idle was raised. I would replace the cap and pull the head to check the bores for ware if you feel a ridge at the top of the bores it is time for a rebuild...

Replace the cap? Do you mean replace the main cap or?

Will I be able to reuse the original crank in my rebuild with the deep slot that been cut into it where the crank meets the thrust bearing?

Here is an enlargement of one of the earlier posted pictures of the crank. As you can se there has been removed a lot of metal

Roald,
At the risk of really opening up a can of worms on this thread, I am jumping in. First off, I did not see where you listed how many miles were on the car. Regardless, I agree with many of the other posts that you should rebuild your engine. Far to much bearing metal in the pan for my taste. You do not know where it has gotten to, especially if the oil filter became plugged. If it was the oil was eventually routed around the filter and will have gone every where. Here is where I am going to get in trouble. Pennzoil was mentioned in an earlier post. It is one of the most popular oils in the states. Probably lubricates very well also. But, to my understanding it is a perifin based oil And over time will build up a sludge in your motor that would make any Corvette enthusiast sick to his stomach. My dad was a mechanic for some 40 years and he told me when I started driving and working on car he would hang me by my b***s if he ever caught me using Pennzoil or Quaker State oil in any car. There it is guys. Especially interested in what Duke has to say about this as from his numerous posts he seems extremely knowledgeable about these things.
John

Unknown how many miles there are on the car, the odometer stopped at 65000 miles but its probably driven a lot more.

I dont know which oil there have been used in it but there was a good deal of sludge in it when I got it, probably didnt help that the car sat for 20 year with the same oil in it and the previos owner unfortunately started the car up on it (he did it before I came and looked at the car)

I think I am going to rebuild the engine, was already counting on it when I bought the car because of the 20 years it was parked.

I have another 68 roadster (I like 68's) so I am not going to be vetteless while rebuilding it

[Dick W.]

Re: Identify engine sound?

Many years ago, the parafin based (Q/S, Pennzoil, Esso, etc) oils got a bad rep for causing sludge. The asphaltic based oils did not do so. But with the advent of modern oils the difference has basically disappeared. The sludge in the engine was more likely caused by the engine not getting up to operating temp and driving short trips

[Jim L.]

Re: Identify engine sound?

Many years ago, the parafin based (Q/S, Pennzoil, Esso, etc) oils got a bad rep for causing sludge.

I've heard this same claim, too. My experience with Pennzoil differs greatly enough that I tend to not believe it: '86 S10 Blazer, Pennzoil 10W30 and nothing else for 209000 miles. Intake pulled at 186000 because of a leaking gasket. The interior of the motor was completely free of sludge.

Jim

[Dick W.]

Re: Identify engine sound?

Jim that was already into the moder era of oils. I saw major changes in oils from the early '60's on. The only thing that the oils of today have to resemble the oils, say from pre '65 is that it is a petroleum base, called motor oil, and is packaged in a quart package. I have watched the better oils come from a Mil Spec 2104-A thru Mil Spec 2104 E? to todays newest rating. I used to subscribe to a publication Lubrication. Reading it you could se the increased requirements that the engine manufacturers place on oil that would be approved for use in their vehicles. GM, Ford, Chrysler, Detroit, Cummins, Mack, John Deere, and others had their own tests that the oil had to pass. If I had the time I would copy a couple of these tests and post them on here.