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dumpdaccord
03-08-2008, 07:51 AM
i have a z6....where the factory header seperates theres two round gaskets, one has a gap in it about 1/4 inch....

i her the knoock coming from the bottom/front of the block(only knocks between 500-2500k rpm...then goes away....

no change in performance although i have no power after 4900k rpm...just makes noise....still gets 30mpg

:thinking:....knock or gasket....im gonna change the gasket but wonderin opinions...


also if its a knock will just new bearings fix the problem or should just grb another motor....

bRiAnMcIvIcS
03-08-2008, 08:42 AM
If its knocking get a new motor. Is it an accord? If so just swap in an h22.

green91
03-08-2008, 08:53 AM
its a z6 so its obviously not an accord. seems like a dumb question to me, go ahead and replace the gasket first, a severe leak can sound like a knock at times. if the engine is knocking you're much better off replacing at least the short block since it seems you aren't very literate as far as engine rebuilding

Thighs
03-08-2008, 09:30 AM
its a z6 so its obviously not an accord. seems like a dumb question to me, go ahead and replace the gasket first, a severe leak can sound like a knock at times. if the engine is knocking you're much better off replacing at least the short block since it seems you aren't very literate as far as engine rebuilding

ive never heard an exhaust leak that sounded like a knock before. usually they make 2 different noises.

but based on the OP, he knows his gasket has a huge hole. that would mean its most likely the gasket. replace the gasket and if it still makes noise, you need a motor.

dumpdaccord
03-08-2008, 09:54 AM
its a z6 so its obviously not an accord. seems like a dumb question to me, go ahead and replace the gasket first, a severe leak can sound like a knock at times. if the engine is knocking you're much better off replacing at least the short block since it seems you aren't very literate as far as engine rebuilding

correct, havent built an engine myself yet.....was just wonderin if a header/exhaust leak could sound like a knock....and the noise goes away above 25k rpm so that made me ify on what the prob is...

bRiAnMcIvIcS
03-08-2008, 09:58 AM
its a z6 so its obviously not an accord. seems like a dumb question to me, go ahead and replace the gasket first, a severe leak can sound like a knock at times. if the engine is knocking you're much better off replacing at least the short block since it seems you aren't very literate as far as engine rebuilding

Well his name is dumped accord, i wasnt really payin attention to what engine he had. Whoops! Good eye green 91. haha. If you replace the motor get a dohc.:goodjob:

Thighs
03-08-2008, 10:07 AM
could it be your lifters? change your oil and see if it goes away

dumpdaccord
03-08-2008, 10:18 AM
could it be your lifters? change your oil and see if it goes away

def coming from down low.....oil is 1600 miles old



Well his name is dumped accord, i wasnt really payin attention to what engine he had. Whoops! Good eye green 91. haha. If you replace the motor get a dohc.:goodjob:

accord sold.....thinkin about ls or gsr but i go back down south to pick up...:(


gonna go get the gasket today and put in tomorrow....

green91
03-08-2008, 06:56 PM
ive never heard an exhaust leak that sounded like a knock before. usually they make 2 different noises.

but based on the OP, he knows his gasket has a huge hole. that would mean its most likely the gasket. replace the gasket and if it still makes noise, you need a motor.

I have heard an extreme leak (basically open dp) that did sound like it had a knock but its the one time that i have heard it.

DaRussian
03-08-2008, 11:44 PM
i have a z6....where the factory header seperates theres two round gaskets, one has a gap in it about 1/4 inch....

i her the knoock coming from the bottom/front of the block(only knocks between 500-2500k rpm...then goes away....

no change in performance although i have no power after 4900k rpm...just makes noise....still gets 30mpg

:thinking:....knock or gasket....im gonna change the gasket but wonderin opinions...


also if its a knock will just new bearings fix the problem or should just grb another motor....



I had the same problem with a LS motor and the problem was my timing was off by like a tooth or two. it did the same thing, it had a knocking sound on low rpms and it did not have no power... i would be flooring it and i would be redlining it but it was really slow.

dumpdaccord
03-09-2008, 11:58 AM
I had the same problem with a LS motor and the problem was my timing was off by like a tooth or two. it did the same thing, it had a knocking sound on low rpms and it did not have no power... i would be flooring it and i would be redlining it but it was really slow.

this is interesting... have to look into this....

Thighs
03-09-2008, 12:11 PM
how many miles are on the motor? sometimes even on 500 mile oil they will click, and ive heard some nasty lifters before. also, did you replace the gasket yet?

Gutling
03-09-2008, 12:14 PM
how many miles are on the motor?

eghonda88
03-09-2008, 12:30 PM
I had the same problem with a LS motor and the problem was my timing was off by like a tooth or two. it did the same thing, it had a knocking sound on low rpms and it did not have no power... i would be flooring it and i would be redlining it but it was really slow.

yep even happend with my b16 that way fixed the timing and changed my oil with the lucas oil addictive its so thick its like honey and it freakin works great:goodjob::2cents:!

Good luck

dumpdaccord
03-09-2008, 03:00 PM
how many miles are on the motor?

260k mi...was told its 180kish...but im guessin its prolly 260k mi...

Gutling
03-09-2008, 03:19 PM
lol yea... pretty sure you need a engine.

dumpdaccord
03-09-2008, 03:20 PM
lol yea... pretty sure you need a engine.ive had over 10 hondas with 150k mi plus and still run strong....mileage doesnt say much.....

Gutling
03-09-2008, 05:00 PM
true, but knocking sure says a lot lol