Loud knocking noise valve cover?

[AWDDSMCRAZY]

Ok first off Ill let you know what we had done first. First of all we just got done doing a ring change. We took off head and everything that needs to be done in order to the the change. Honed the cylinders and reinstalled. When we started it back up it seemed to run fine. We heard this wierd noise when we would touch the throttle and let off.

We did the break in and proceeded to change the oil after 20 miles and this is where the problem came up. The car started and ran fine, and drove away. Unfortunately he had to drive to x-mas 200 miles away. The car broke down. It started making this loud noise from the valve cover area.

Checked the timing belt and its still dead on. We covered up all the oil and water passages when we scraped head gasket and honed.

What should we look for? We are freeeeekin out.

 

[prplhz96]

it can be anything, from collapsed lifters, to bad bearings(main, rod, b.s, engine noise travels, so the noise you think is coming from the vc can be from the bottom end). Best bet would be to pull the vc, and give everything a once over. Also was oil pressure affected at all after the breakdown?

 

[sonicnofadz]

Put the car on ramps or jacks, and have someone get under the car while its running (potentially dangerous but be a man) and listen to the noise from under the oilpan. If the noise is coming from the block it should be louder underneath the car. My guess is that you just have some bad lifters.

 

[SinaiTSi]

Did you check the timing belt just up top, or did you also check at the crank sprocket. I all of a sudden had a horribly loud knocking noise come from my car a few months ago. The timing matched up perfectly, but, i realized that at the crank sprocket is where it must have jumped a tooth. I'd say a loud ticking would be the lifters, if it's a loud knocking coming from the valve cover, most likely it's the valves smacking the pistons. I really hope it's not for your sake. Also, do a compression test, this will tell you if you have any bent valves. Hope that helps.

 

[Old Mitsu Tech]

I have seen rockers come off the lifters and valves and get hung in around the cam. It's a horrible noise and usually with some pretty bad damage to the surrounding areas. Pull your valve cover and visualy inspect all 16 valves exhaust and intake. At least if I'm wrong, you are ok there.

Good Luck

 

[v2ner]

are you runnin a FMIC?

 

[SinaiTSi]

are you runnin a FMIC?

Just curious, what does that have to do with knocking under the valve cover?

 

[v2ner]

usually when you're runnin a FMIC, you will leave the breather hose unplugged or plugged into a catchcan instead of having it plugged into the intake. this, causing the oil to not go into the intake tract which leads to my reason. lifter tick. i've noticed this on a considerable amount of DSMs i've worked. come in w/ lifters ticking like crazy and once the FMIC is on....after about a week of driving, the ticking goes away. just my experience.

 

[AWDDSMCRAZY]

Sorry it took so long to get back. I guess we shouldnt have used the same rod bearings although we put them back in the same way. They died say the least and took the crank with it. It looks as if somehow the new head gasket blew during break in and water got down in the oil. I guess the water ended up making the bearing go bad.

 

[Old Mitsu Tech]

When you do your rebuild, make sure that the head is completely inspected for cracks and warpage. Take it to a reputable shop to have tested.

Good Luck

 

[sonicnofadz]

This is why its good to use a machine shop!