Strange Engine Sound- Knocking type sound, with video!!! Options

[tornik550]

I have slowly been rebuilding my 914 over the past few years. I have the engine running however it doesn't sound right to me. It seems to be making a knocking type noise that doesn't change with timing adjustments. I haven't heard the car run for awhile so I am not sure if it is a normal type 4 noise. I do not think that it is normal for a stock engine however my engine is not stock. This is the reason why it is tough for me to determine whether it is a normal sound (I have never heard it run for the new parts- or at least I don't remember hearing it).

My engine is now a 2.2l. It was a 1.7- then the previous owner upgraded it to a 2.0l. I put in a new crankshaft and now it is 2.2l (I forget exactly). I changed to chromoly pushrods (non-hydraulic lifters). The valve lash is set at 0 (I doubt it but I suppose its possible that something came loose and the lash could be off now).

The video was taken in about 30 degree (f) weather. The engine is cold. I have not ran it long enough for the engine to warm up (I only started it once today- I did let it warm last week to set the timing but I do not remember if the sound went away). I obviously do not have the muffler attached (just the heat exchangers).

Does this knocking type sound seem to be normal for chromoly pushrods or does it seem to be an issue? If a different issue, where should I look.

http://www.youtube.com/watch?v=F0GyMjs6SaI

[VaccaRabite]

What kind of valve adjusters are you using? Elephant feet?

If so, pull your valve covers and look a the inside to see if the adjusters are impacting the inside of the valve covers. I had that happen with mine.

Zach

[tornik550]

What kind of valve adjusters are you using? Elephant feet?

If so, pull your valve covers and look a the inside to see if the adjusters are impacting the inside of the valve covers. I had that happen with mine.

Zach

I am using elephant feet. Am I correct in assuming that if they were contacting, I would see impact marks on the covers? How did you resolve your problem? Unfortunately, my engine is a wide load due to jug spacers and I do not have much room for bigger covers.

[Dr Evil]

You can grind/file down the heads of the lifters and re slot them if they are too long. You will see impact marks on the covers on the inside.

[VaccaRabite]

Mike nailed it. Grind them down a little, and cut a new slot for the screw driver. Mine needed to come in ~1/10th of an inch. Less then that, really, but we ground them to have a little extra space.

You want to do this,if it is the problem. if not, you could either put a hole in the valve cover, or unseat it. Either one would cause a nasty leak.
Zach

[tornik550]

Vacca Rabite gets the award (IMG:style_emoticons/default/beer.gif) I just got under the car, took the valve covers off and there were clear marks that the valve adjusters were hitting the valve covers.

Thank you!!!!

[VaccaRabite]

(IMG:style_emoticons/default/smilie_pokal.gif)
I like the easy problems. They make me look good. And I need all the help there I can get. (IMG:style_emoticons/default/biggrin.gif)

Zach

[ME733]

(IMG:style_emoticons/default/smilie_pokal.gif)
I like the easy problems. They make me look good. And I need all the help there I can get. (IMG:style_emoticons/default/biggrin.gif)

Zach

................good job........way to go..........

[tornik550]

I thought that I would add the way that I fixed the valve adjuster issue. I tend to go with a more caveman approach to things. I took the valve covers off, got out my air hammer. With the air hammer, I bowed out the areas of the valve covers that were hitting the valve adjusters. I bowed the cover out enough for clearance but not too much so the bucket handle still works normally.