What is this knock...
 

Mysterious knock...prompted me to...
Replace all lifters (5 were gone), determine it was not vacuum pump...Noise seems to come from intake runner #2. Other than this, the car runs great! This noise came in and out over a period of two weeks. And now it's terrible. So, what could it be? Cranking the injector lines off on each cylinder makes no difference at all.

Guys, I've checked the timing; it's perfect...There is no excessive blowby...The engine has very strong compression....It just has a terrible knocking noise that is consistent at all rpms.

I will rev the engine in future video clips. So, if it isn't fuel related, it isn't the pump, it isn't the injectors, what could it be?

http://youtube.com/watch?v=JPFZIiT9bdk

I'm generally an optimist. I don't want to even think it's a bottom-end issue. The car does not burn any oil. It runs super. It definitely sounds like it's coming from up top, but the valve-train is super tight, now.

doesn't look there is much oil shooting out.

Thats what I was thinking too....shouldn't the cam lobes be like....bathed in oil?? :eek: Where is all the oil????

I started my gasser up without the valve cover on and oil was splashing everywhere

I think that sound is the sound of the rod hitting the crankshaft and spinning the bearing without any oil...

Exactly what I was thinking.....it does sound very much like a bad rod knock....

I agree on the lack of slinging oil. And hold that camera still for a second! :D

Oil Pump
 

Little or no Lubrication of Camshaft.
Knocking elsewhere.(Pray it's not a rod)

Weak oil pump...or clogged oil galleries.

I know it's not LOW on oil! (Please God?)

No, it's not low on oil (your prayers are answered). Although it sprays that oil out rapidly with the v-cover removed, I'm careful to always keep it above the min mark on the stick.

Thanks guys. I will follow up when I find out what it is. Here's another clip where I vary the engine revolutions. This digital camera does not provide the best video or sound quality, I guess. Comparing one 603 to another, I also think there should be more oil getting to the top.

http://youtube.com/watch?v=nbcWMyM4p-w

I agree with the comments related to very low oil to the top end. Something is amiss there.

The knocking speed is at camshaft speed.........about 5.5 knocks per second.......giving you some potential for a low cost repair.

However, I'd disconnect each injector line in sequence while it's running and pray that the knock doesn't disappear when one of the cylinders comes off line.

Brian, I have done this. It doesn't seem to change the value of the knocking, whatsoever. On any cylinder.

Just to prove it, I'll post a video tomorrow of cranking the fuel lines one-by-one.

Thanks again.:)

Good job. That test more than likely rules out the bottom end. No need for further confirmation if you've done it already.

You've got an issue with low oil and some possible damage to the valve train due to the lack of oil. It could be as simple as a completely collapsed lifter...........even if brand new.

Why would this rule out the bottom end?... All he did was check to see if the injector was knocking, not if the rod bearings are coppered? The only other thing i can think it would be is a collapsed lifter, wich would go with the low oil theory as well....

Without the combustion pressures, the noise should be significantly reduced, if not eliminated. The noise exists at 1/2 engine speed...........so, either it's valve train related or combustion related on the bottom end.

I've discounted the possibility of an injector knock..........it appears to be too harsh for that situation.

Wow....the 603 is one sweet sounding engine when its revved up! :eek: I never realized it sounded like that. Maybe I will have to consider one someday. :D :D

Ding, ding, ding...

An update to this thread...That horrible knock....

Turns out the oil galleries were plugged. There was inadequate lubrication to the top end. Blowing compressed air through gallery plug (at the rear of engine) seemed to solve the problem. Oil sprays everywhere, now.:D

You guys were right. She runs very well, now. Thanks.

That begs the question.............why??

And, how did you correct it............did you need to remove the head for that job??

Why? Good question. There appeared to be some sludgy goop dribbling out from the bores. It was like tar, really. I'm just happy my car runs well. The car originally had a K+N filter and a Slick50 sticker on top of the air-filter element cover. If that's a clue.

I simply used an air gun and blew through the oil cavity at the rear of the engine accessed via a 7mm (I think) allen bolt . Tight squeeze, but I got in there. The head, cam, and lifters stayed in place for this. I only had to remove the valve cover. I directed air through until I observed the bores dribble oil over the lifters. The engine is super, now! But I'm watching it. I drained the oil and now I'm running Marvel Mystery Oil 1.5 qts, and synthetic. We'll see.

The mix you now have in the crankcase will hopefully clean all the gunk out everywhere . Perhaps a past owner was just an oil additive believer.

I have heard that viscosity increasers can be found as a mass lump in the bottom of the oil pan on teardown occasionally for example. Does sound like there was something in that engine oil to build up enough to partially plug passages. A good warning to others perhaps.

Of course it could have been just sludge from something else like using non detergent oils long term. I suppose they might be still on the market. I well remember nu gold oils sold through a national chain in Canada for .25 cents a quart. That was awhile ago though. Your american equivelent might have been about 15 cents a quart.

We used tons of the stuff in our oil burning gas cars. . In fact it was thought that changing an old car from non detergent to detergent type oils might increase oil consumption signifigantly. Times have changed. Even worse is the possible senario that slick 50 actually does something in an engine. You could drop them a testimonial.:rolleyes: