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I started my car up today and it almost sounded like it was knocking but it real quiet.. the oil pressure started out at 40 leveled at 20 for a while...then when i pressed on my gas it dropped... and when i left off it went back up.when my engine got warm it sounded like my #1 pistion was banging still quiet tho.....im so confused on what the problem is
Is it a nunga nunga sound ? cause if it is get ready to pull your motor, from what you describe, it sounds like the motors run a big end bearing.
Did you check the oil level ?Quote:
Originally posted by YoungMalibu
I started my car up today and it almost sounded like it was knocking but it real quiet.. the oil pressure started out at 40 leveled at 20 for a while...then when i pressed on my gas it dropped... and when i left off it went back up.when my engine got warm it sounded like my #1 pistion was banging still quiet tho.....im so confused on what the problem is
I check my oil its good, so if its a bearing, do i need to get my whole engine rebuilt or can i just get it replaced..
IF it IS in fact a spun rod or main bearing, the crank will have to be at the very least polished, but most likely reground. If a main spun enough to damage a main journal, you may have to align-bore the block.Quote:
Originally posted by YoungMalibu
I check my oil its good, so if its a bearing, do i need to get my whole engine rebuilt or can i just get it replaced..
Are there metal filings in the oil?
Well, the thud sound it right.. i cut open my oil filter and it is a shiny metalic look with a couple lil pieces of metal.. So what price range am i looking at to get this fixed.. or am i looking at a total rebuild
When I was interning at Dodge dealership we had a few cars and vans comming in doing the EXACT same thing. Start it up, does alright a little knocking, drive down out of the dealership and then it knocks more but not real loud at all and then the oil pressure drops when you apply the throttle more. We took a look at the engines took the heads and all off and oil build up in a few that looked like a few barely ever had an appropriate oil change and we had to just go put in a WHOLE new engine and then the others needed bearings and all or rebuilt. Take the engine apart and see what's wrong with it.
You won't need a whole new engine or nothing of course we only did that because one was a Altel van with the tires all in wire from worn so much and not taken care of so the company brought one over. And I know I am not the one here that gives the info or nothing and I get crap about how I should not say nothing but unless someone dissagrees with me here then I know that could be a possible problem.
I just experienced the same thing with my 327 drag motor. Sounded fine, ran great, but had a slight rattle sound above 2,000 rpm and the oil pressure began to fluctuate.
Turned out I had a main bearing cap break in two and apparently the crank vibrated so violently that the other main caps are egg-shaped and will not hold a bearing shell(nearly 1/8" play between shell and cap!). Hope yours isn't like mine!
Bowedup
anytime you lose oil pressure when you step on the gas and it goes back up your oil pump is catching air low oil level will cause this or pick up tube not installed properly as for the nock its hard to say running low on oil can cause bearing failure or lifter noise
withdrawn
Well in our case it wasn't our oil pump, it needed a new engine...;)Quote:
Originally posted by big489
anytime you lose oil pressure when you step on the gas and it goes back up your oil pump is catching air low oil level will cause this or pick up tube not installed properly as for the nock its hard to say running low on oil can cause bearing failure or lifter noise
Quote:
Originally posted by FMXhellraiser
Well in our case it wasn't our oil pump, it needed a new engine...;)
did the oil pressure go up and down or did it go down when you step on gas and go up when you let off two diffrent symtoms two different problems.;)
if its full of oil and every thing is ok then when you step on the gas the pres. goes down and when you let off of it it goes back up thats a sign of a worn main bearing. :eek:Quote:
Originally posted by big489
did the oil pressure go up and down or did it go down when you step on gas and go up when you let off two diffrent symtoms two different problems.;)
been building engines for 25 years never seen worn mains do that :DQuote:
Originally posted by lt1s10
if its full of oil and every thing is ok then when you step on the gas the pres. goes down and when you let off of it it goes back up thats a sign of a worn main bearing. :eek:
Sounds like mains to me. The knock might be a lifter, unless it's coming from under the engine. You can replace your main bearings alone, but that is not a good idea. I replaced rod bearings and a couple weeks later the mains starting knocking. I would take it and get an opinion from a mechanic or two. Machine shop here is about $600 to do a long block, if you do the rest yourself.(ex. pull it,strip it, put all back together)
When you find out remember to come back to CHR and let us know what you found.
never mind
Quote:
Originally posted by big489
$600 will get you overhaul not a rebuild and if you don't know what your doing you maybe doing it more than once there is a reason you lost a bearing engines can run several hundred thousand miles on the original bearings why did yours go bad.
What does this have to do with his ride?
Are you here to sell something? Like an overhaul?
trying to save him money you try to misslead him and cost him more money i have a machine shop close to him and i'll help him all he wants for free but if he needs someone to do the work the price is what it should cost he can get the work done where ever he likes the are alot a people who would scam him if he doesn't know whats going on. if you want to help give him advice that is sound and not hogwash.Quote:
Originally posted by jramshu
What does this have to do with his ride?
Are you here to sell something? Like an overhaul?
Get over yourself dude. Everyone is entitled to his/her opinion here. I ain't on here telling him you are full of "hogwash" now am I? Why in the hell would I be trying to mislead him? What do I have to gain from it? Not a thing is what.
The car I was referring to I bought from a relative. When you started it the idle was at about 2500rpms. So eventually that was the demise of the engine I assume. Probably not good to rev that high when first started. I was broke, just got married, and on my way from Texas to Cleveland. Got to Tenn and had a rod knocking, had no money so all I could afford was the rod bearings. Had I the money I would have done mains also, I am positive they were as bad as the rods. Nothing was done wrong, nothing done twice. Car ran the same a few years later, and I sold it as is. Rattling mains and all.
Quote:
Originally posted by big489
been building engines for 25 years never seen worn mains do that :D
THAT JUST TELLS ME YOU ANT SEEN EVERYTHING THEN. old 235 and 261 chev. was good for that. when you step on the gas it causes the crank to move to one side and that causes more of a leak by the bearings. i wont telling him to do anything, just where he is loosing his oil pressure. :confused:
i'm not the one knocking what others say but a V8 oils differnt fon a six the fist thing to get oil pressure on a chevy is the oil gage. if we where refering to an old six my comments would have been different in 25 years i've seen alot people will but a new oil pump in and leave the screen loose sucks air oil drops. for his oil pressure to do what he is saying it does he would have more than a soft knock. I have seen bearing totally gone hand the engine still have normal oil pressure you sa can't happen bearin gaulds and fill oil hole in crank no pressure loss. I know what i'm talking about and i offered my help but i'm the new guy here and you geriatric members only want to slam me I don't care i'll go somewhere else.
I'm not old and I would not have even posted anymore, till you started on me. If you can give yours I can give mine. That don't mean run off, just back off. CHR could use the input of a machinist.That's all I have to say.
you not offering help,you are stating facts and i got news for you, all it is is an opinion and they are like ass holes every body got one. yrs dont mean nutten to me, im almost double yours.Quote:
Originally posted by big489
i'm not the one knocking what others say but a V8 oils differnt fon a six the fist thing to get oil pressure on a chevy is the oil gage. if we where refering to an old six my comments would have been different in 25 years i've seen alot people will but a new oil pump in and leave the screen loose sucks air oil drops. for his oil pressure to do what he is saying it does he would have more than a soft knock. I have seen bearing totally gone hand the engine still have normal oil pressure you sa can't happen bearin gaulds and fill oil hole in crank no pressure loss. I know what i'm talking about and i offered my help but i'm the new guy here and you geriatric members only want to slam me I don't care i'll go somewhere else.
sorry but you started on me first and i mean senior memberQuote:
Originally posted by jramshu
I'm not old and I would not have even posted anymore, till you started on me. If you can give yours I can give mine. That don't mean run off, just back off. CHR could use the input of a machinist.That's all I have to say.
i'll be happy to back off but you need to watch your comments also
Originally posted by big489Quote:
Originally posted by big489
i'm not the one knocking what others say but a V8 oils differnt fon a six the fist thing to get oil pressure on a chevy is the oil gage. if we where refering to an old six my comments would have been different in 25 years i've seen alot people will but a new oil pump in and leave the screen loose sucks air oil drops. for his oil pressure to do what he is saying it does he would have more than a soft knock. I have seen bearing totally gone hand the engine still have normal oil pressure you sa can't happen bearin gaulds and fill oil hole in crank no pressure loss. I know what i'm talking about and i offered my help but i'm the new guy here and you geriatric members only want to slam me I don't care i'll go somewhere else.
been building engines for 25 years never seen worn mains do that
thats not telling me i dont know what im talking about?:confused:
maybe you should try reading what is being posted hammering on me doesn't help this guy all you are doing is chaseing off members GOODBYEQuote:
Originally posted by lt1s10
you not offering help,you are stating facts and i got news for you, all it is is an opinion and they are like ass holes every body got one. yrs dont mean nutten to me, im almost double yours.
Quote:
Originally posted by jramshu
Sounds like mains to me. The knock might be a lifter, unless it's coming from under the engine. You can replace your main bearings alone, but that is not a good idea. I replaced rod bearings and a couple weeks later the mains starting knocking. I would take it and get an opinion from a mechanic or two. Machine shop here is about $600 to do a long block, if you do the rest yourself.(ex. pull it,strip it, put all back together)
When you find out remember to come back to CHR and let us know what you found.
Now big489 what part of my post was about you. Except the price difference from the machine shop. You might do more than what this one here did. Then again it is another state. Things up there are a little higher than down here.
When you make over 100 posts you get the senoir status.
Maaaaaaaybe, just maybe, he hasnt seen the scenario. Anything is possible. But as for the 6 and 8 oiling different, No. Especially when you consider most V6s are built based on prior V8 blocks. Unless there is a massive difference between a oil pump for a 6 pulling oil from the crankcase and moving towards the top of the motor and an 8 doing the same thing, Im missing something. As for the motor in question, did anyone suggest doing a running compression test? Seems to me that would tell if it was a rod bearing doing the warping and causing a drop in pressure;)
i gave him my opimion and it would have over with if you had'nt turned you noise up at my answer. i dont see how you can put this off on me. you sounded like i did about 6 mo ago. it didnt work then and it ant gomma work now.:(Quote:
Originally posted by big489
maybe you should try reading what is being posted hammering on me doesn't help this guy all you are doing is chaseing off members GOODBYE
This is not helping the guy.
. thats the first time ive heard anybody say check the comp. to see if the rods bearings are worn. whats that got to do with oil pres.? the thrust bearing get worn and lets the crankshaft move all over the place, you will loose a lot more oil pressure by the main bearings than the rods if every thing else is the same. when you mash on the gas the crank will move one way or the other and loose a lot of pres. by the main bearings.:HMMM:Quote:
Originally posted by drg84
Maaaaaaaybe, just maybe, he hasnt seen the scenario. Anything is possible. But as for the 6 and 8 oiling different, No. Especially when you consider most V6s are built based on prior V8 blocks. Unless there is a massive difference between a oil pump for a 6 pulling oil from the crankcase and moving towards the top of the motor and an 8 doing the same thing, Im missing something. As for the motor in question, did anyone suggest doing a running compression test? Seems to me that would tell if it was a rod bearing doing the warping and causing a drop in pressure;)
he was talking inline six sp was iQuote:
Originally posted by drg84
Maaaaaaaybe, just maybe, he hasnt seen the scenario. Anything is possible. But as for the 6 and 8 oiling different, No. Especially when you consider most V6s are built based on prior V8 blocks. Unless there is a massive difference between a oil pump for a 6 pulling oil from the crankcase and moving towards the top of the motor and an 8 doing the same thing, Im missing something. As for the motor in question, did anyone suggest doing a running compression test? Seems to me that would tell if it was a rod bearing doing the warping and causing a drop in pressure;)
no kiddingQuote:
Originally posted by jramshu
This is not helping the guy.
whatever try helping the guy instead then read the other threads add your opinion and move onQuote:
Originally posted by lt1s10
i gave him my opimion and it would have over with if you had'nt turned you noise up at my answer. i dont see how you can put this off on me. you sounded like i did about 6 mo ago. it didnt work then and it ant gomma work now.:(
sorry if i offended anyone just trying to help the guy with the problem
I think csf03716 gets the cookie on this one... good pressure at idle with low pressure at higher rpm's is a symptom of oil cavitation from a resriction in the inlet side of the pump. Combine that with a probable minor leak in the pickup tube... problem solved.Quote:
Originally posted by csf03716
hows this sound....its known hes got a knock...probly from lack of lube on initial start up......as for the pressure fluctuation...heres my take....his oil screen is so chocked off with sh*t, that it will just barely suck enough at idle to give a reading.....but once he revs up, it won't allow enough oil into the vanes/gears, and its cavitating/starving for fluid and wont register a reading until the suction equalizes with how much the dirty screen will allow into the pump itself!....so the supply can't keep up with the demand .....plan and simple deductive reasoning.......any feed back?...charlie......oh Tech! where are youuuuu?
Now go take the thing apart so we can all find out what happened!!!!:whacked:
I'll go with that, but I like my beer just like my coffee... dark, bitter, and chewy. I guess I'll bring my own...Quote:
Originally posted by csf03716
thanx "grinder"...can i trade the "cookie" for a cold 30 pack of Coorslite?...
what i been saying the whole time up until people started knocking me
it don't make any dif. L6, v8 if the thrust bearing is worn bad enough to allow to much end play in the shaft, when the motor is revved. up the crank shaft moves one way or the other taking up all the slack in the shaft and causing a max. amount of oil pressure drop past the main bearing and when the motor peaks out the shaft will center itself and the pressure will go back up. it may be worse in the L6 motors but it wil do that on all motors. if its idling at 10 lb. and you snap the accelerator the pressure will go down to say 4 lb. before it starts back up to say 25 lbs. you see a motor doing that and you can be sure its main bearings wear. :cool:Quote:
Originally posted by big489
he was talking inline six sp was i
this is sound adviceQuote:
Originally posted by DennyW
Start your car up. Note pressure. Let it run until warm. Note your pressure. Now, sitting still, raise the idle up to a fast idle, while watching pressure, and noteing any sounds you hear. If you hear a knocking sound then, that would be a rod knock, most likely. Hows the oil pressure? Then, let it idle, put it in gear. Note oil pressure. Now, while holding brake, put a load on the motor, like torqueing it up (power braking), and note the oil pressure. If you hear a thumpping sound, and pressure drops, it's the mains. Last, it you cruise on the highway, while watching oil pressure. If it starts to drop as you gain speed, you most likely have a pickup tube that is clogged. If it comes, and goes on the oil pressure, it's probably sucking air. :)