Hello,
i need your help with my rebuilded engine. Specs
- eagle rods
- kb pistons 10.2:1
- comp cams roller cam, special grind
- johnson hy lift s roller hydraulic lifter
- isky double valve springs
- harland sharp roller rockers
- isky guideplates
- balanced crank
- smith brother pushrods oio restricted
- dmr roller cam parts to hold it steady

like in the video, the car sound like a diesel.
i already checked the pre load on the lifters and talked to johnson, it‘s ok.
i checked the oil, it‘s ok.
the pushrods looks good.
the car runs good, and all cylinders are there.
but the noise is too loud to be normal.
if anybody got an idea, i would be very grateful.
i never heard such an weird engine sound.
i want to check the timing chain, water pump etc..
after two weeks on searching for the sound, i needed a weekend of.

thanks

https://youtube.com/shorts/LCOBWxwKJso?feature=share

 

Your video is private it seems.

 

sorry, i changed the settings

 

Put a hose to your ear and try to isolate what area it's coming from.

 

How's the oil pressure?

The Sniper EFI is noisy, but not THAT noisy.

 

Ya hows the oil PSI?
Drain and inspect the oil. Cut the filter open. Did you properly run-in the cam?
To my ear, it sounds like metal to metal of the reciprocating parts. Or extreme valve train noise.
Pull the plugs and spin the engine on the starter.
What happens if you rotate the distributor advance & retard while running?

 

- the oil looks good, it doesn‘t sound like a baering damage
- i could not break in the cam, because of that noise. I am afraid to damage everything
- when i spin the engine without plugs, everything sounds fine
- oil pressure is high, about 30-40 psi idle. I got the hv pump
- when i retard the distr. the sound is the same
- maybe the timing chain?

 

It could be piston slap. Was the engine bored?
What is your piston to bore clearance?

 

- the engine is bored, clearance is about 0,9mm, 0.035“
- they bored it to the specs from kb für petrol drag race/hauling

 

Are you off by a decimal place?

 

- yes, sorry my bad its too long ago 0,0035“

 

Pull the valve covers and watch the rockers. Its likely valve train noise.
Did you shave the block and heads? If so did you recalculate the geometry? It sounds like the rockers may be too tight overloading the cam.

 

- the block and heads are decked
- the rocker pads are milled down for the guideplates about the thickness from ghe guideplates
- i took the preload from johnson, it‘s about 1/2-3/4 turn (0.8mm) it‘s not much, i tested it out, you can make about 2 full turns till end
- do you mean i should take less preload? I also tried more preload, same noise no difference
- i wachted the rocker but saw nothing suspicios

 

What are the specs on the camshaft ? What part number piston ? Are the valves stock size or have larger ones been installed ? The reason I ask these questions is I had a customer years ago with a Ford engine that sounded just like that. He had installed larger valves in the heads and all of the intake valves were barely hitting the edge of the valve cutouts in the pistons.

Do you know anybody with a bore scope to take a look in the spark plug holes ?

 

Statically back off all rockers and reset with a little play on each rocker each cylinder with both valves closed TDC.
With the engine running back off rockers till they clatter then down a 1/2 to 3/4 turn. You should see oiling from the push rods.
Too much pre-load will collapse lifters bend valves and push rods & wipe cam lobes and make that sound.

My bet is you didn't pre-bleed the lifters and tried to adjust them w/o internal oil, thus bottomed out?

 

- thank you, i will check that. A friend of mine got a bore scope

 

- the lifters doesn‘t came with oil in it and the instructions said don‘t fill them. I also turned the oil pump with a drill till oil comes out the lifters.

- i dont think that i bottomed them out because the car runs good and i measured every valve with the gauge, there is plenty of way for the hydraulic element in the lifter

 

Damn thing sounds like a 7.3 SD Ford or a Cummins. The noise rattles like diesel injectors. This means the sound is likely cam revolutions vs crank.

Check for spring bind. Pull some rockers and look for witness marks on the tip and rocker body. Was the cam lift, spring, and stem height included in the valve train equation?

Was it stroked?

Scope the cylinders looking for valve contact.

 

- it is not stroked. I checked for coil bind but there is plenty of room. Reall tricky

 

Timing chain wrong assembled?
Can someone tell me if i installed the timing chain retarded?

 

Wondering how this would cause the noise.

 

talked to cutlassefi,
i installed the timing chain wrong. This could cause the noise

 

I think you found your problem. That is not correct.

 

You should be lined up with the dot that my arrow points to. And I hate to say it but there is a good chance you now have some bent valves

 

i will check the pistons for impacts, if there is nothing to see i am lucky.
my luck its between the retard and 0 position, the car runs good. I think nothingb happened

 

I hope I am wrong but I think the noise is from the valves touching the pistons

 

It does sound like an engine that is way off on timing and dwell.
I asked about the stroke to make sure nothing is contacting the block oil pan etc. Rockers contacting valve covers etc.

 

- you are right. I will correct the chain and check for compression/leak down test.
it is really embarrassing 😁 i will tell you if everything is ok or not

 

Don't be embarrassed its how you learn. Hopefully, nothing is broken. Definitely check for piston to valve contact with a scope.
If you see light contact pull the push rods and roll on a flat surface to verify they are straight. Heavy contact means check for bent valves and deeper problems which means disassembly to check everything..

 

The problem is found
i corrected the chain timing and the noise is gone.
i also checked compression and it looks very good.
thank you for all the help

 

Thank you for following up. You win this round.