View Full Version : strange loud ticking noise under plenum
shaynezrl
09-29-2010, 12:08 PM
I have a strange loud ticking noise from under plenum. Also i noticed when i drove the car this morning that the oil pressure gauge was erratic and eventually went to 0. When apply throttle it goes back up to normal reading. Could it be the oil pressure gauge that causing this and need to be replace?
xlr8nflorida
09-29-2010, 12:17 PM
I have a strange loud ticking noise from under plenum. Also i noticed when i drove the car this morning that the oil pressure gauge was erratic and eventually went to 0. When apply throttle it goes back up to normal reading. Could it be the oil pressure gauge that causing this and need to be replace?
The oil pressure sensors are known to go bad and are cheap.
Check your oil level.
The ticking would make me nervous, what kind of ticking?
TFENT
09-29-2010, 12:22 PM
The ticking could be a plug wire. I know that when I was messing with my Z a few weeks ago we were pulling the plug wires to find a dead cylinder and it was definitely a loud click when it would fire. Just a guess...
shaynezrl
09-29-2010, 01:07 PM
The noise sounds like its coming from the lifters and travel up to plenum. Oil level is fine. The noise gets louder when apply throttle.
rhipsher
09-29-2010, 01:25 PM
Bad lifter.
There are two oil pressure sensors on the LT5. The big one on the top of the oil filter adapter is the sender for the gauge. The other is for a warning light on the panel.
The top sensor has a male 1/8"NPT thread where it screws into the oil filter adapter housing. I suggest that you buy a 4" long 1/8" pipe nipple & the fittings to attach a pressure gauge (suggest 0~100 psi or there-abouts) Install the gauge & see the pressure before installing a new sender. The whole test apparatus can be had for about $25.00.
The ticking sound made by a lifter can be one of the first indicators of low oil pressure. You need to know from a real gauge. Afterwards, you will know if your sender is bad, whether a new one is needed and how accurate your dash panel gauge is reading.
If oil pressure is above 15 pis at idle and the ticking is still present, set emerg brake, put in 2nd gear, no throttle and slowly release the clutch untill engine rpm pulls down. Get back to us if the noise quits when a load is on the engine.
Ccmano
09-29-2010, 02:36 PM
Have you recently changed the oil and filter?
H
shaynezrl
09-29-2010, 10:02 PM
I did change the oil and filter recently. The motor ran fine after the oil change. I will spend sometime on Friday. Jerry is probably right and i will follow his suggestions. I will get back to you guys on this.
Shayne
PhillipsLT5
09-29-2010, 10:29 PM
antioch, IL?
you could go see Marc H
tccrab
09-29-2010, 10:44 PM
antioch, IL?
you could go see Marc H
Nope.
He's in Antioch CA.
It would be a 3 day drive to see Marc H.
How many miles on her?
Has she made this sound before?
What filter and what oil did you use?
Normally the mighty LT5 is nearly bullet proof so I wouldn't be too worried... but you never know...
TomC
'Crabs
Ccmano
09-29-2010, 11:13 PM
At the risk of asking the obvious, is the oil level correct? No offense, but some times it's the obvious things we overlook when looking for the complex.
H
shaynezrl
09-29-2010, 11:23 PM
At the risk of asking the obvious, is the oil level correct? No offense, but some times it's the obvious things we overlook when looking for the complex.
H
NO offense taken..I did check the oil three times. The level check out full at the max. the only thing i did differently was during the oil change i did drained the oil cooler also. I have to check that out too if i tighten all the lines.
LGAFF
09-29-2010, 11:31 PM
Injectors can tick also......they can tick they can tock, they can go like the hand on a door, knock knock.
Sorry read Mr. Brown can Moo too many times, its an impulse.
shaynezrl
09-30-2010, 10:15 PM
Test confirm today using Mac tool oil pressure testing kit. I have no oil pressure. The gauge read at 0 in three times out of five testing sessions. I guess new oil pump is in order.:cry:
Shayne
Ccmano
09-30-2010, 10:30 PM
A failed oil pump would be highly unusual. I don't have an oil flow schematic in front of me but in believe the oil filter is before the sensor in the flow from the pump. I would change the filter and give it another thry.
H
shaynezrl
09-30-2010, 10:48 PM
A failed oil pump would be highly unusual. I don't have an oil flow schematic in front of me but in believe the oil filter is before the sensor in the flow from the pump. I would change the filter and give it another thry.
H
I thought it is unusual for the pump to fail like this too. One day the motor run top notch the next day nothing. The ticking noise is from the lifters due to no oil go up to lube them. I will give it another test tm. I am trying to fine the Helm manual when i am done posting this thread.
Shayne,
The only thing out of the ordinary during your oil/filter change was draining the oil cooler. A shot in the dark here...... but at any time did you ever put rag or paper towel in the oil cooler, lines or oil filter adapter to help control the mess that goes along with draining the oil cooler?
It just doesn't seem likely to me that your oil pump suddenly failed, nor does the filter seem likely. There are bypasses for both the oil cooler & oil filter to maintain oil flow if either is plugged. However, if there was some foreign material blocking flow to the oil filter and the oil filter bypass, then you would see 0 oil psi at the oil filter housing sender.
Until this gets tracked down, avoid running the engine, because ALL oil goes through the oil filter adapter housing FIRST, so nothing is getting oil, lifters, cams, crank, rods, etc.
If you think there is is a possibility that something may have gotten in there during the oil cooler draining, let me know & I can send you a spare oil filter adapter housing to try. it's not a big job to switch them out.
Right now, that's all I can think of.
shaynezrl
10-01-2010, 02:43 AM
HI Jerry,
When i disconnects the oil coolers i did not cover it with rags. I simply put a rag and paper towels under the fittings so oil can collects on the towels (it wasn't much oil) when the motor is cold. I removed the oil cooler and drained the old oil out from the bottom using an L wrench. I reverse the procedure and everything went back together as it should... then fill the motor with oil. So i don't think anything would of gotten in the motor. My brain's been storming like crazy thinking what could have happen? :dontknow:
shaynezrl
10-01-2010, 10:59 AM
DO NOT run the engine! If you drained the oil cooler without replacing that oil.....you have a lot of air in the system. After your original start up, did you add more oil?
After the first start up i added 4 more quarts of oil.
DO NOT run the engine! If you drained the oil cooler without replacing that oil.....you have a lot of air in the system. After your original start up, did you add more oil?
Not really. Oil from the pump also feeds directly to the oil cooler, as well as to the oil filter. There is an oil cooler thermostat in the oil filter housing adapter that prevents oil from passing through the oil cooler until it reaches a specific temp which is above normal driving temp. It operates much like the coolant thermostat except with a sliding sleeve valve.
Any air trapped in the oil cooler would "bleed" into the filter loop as the valve gradually opens & then on through the system as the valve cracks open. it is not a snap close-open-close valve. In all probability, air in the oil cooler loop probably bleeds around the sliding sleeve valve without it ever actually opening, allowing all air in the system to be processed out.
At this point, I'm not sure what's going on. If the oil filter was plugged for some odd reason, the oil filter bypass should/would open. For no pressure, the bypas would also have to be bad. Changing oil filters is certainly an easy & inexpensive test and logical next step.
Do you have a low oil pressure indicator light illuminated in the dash panel? If it is working (big question) it would illuminate. If low pressure and no light, it could be the sensor plug, sensor or the bulb in the panel not working.
The low oil pressure sensor is directly in the oil pump discharge circuit and would be the best indicator of oil pressure before all the cooler & oil filter valves. If the low oil pressure sensor weren't so hard to get to..... pulling it out & testing pressure there would definitely verify pump output.
shaynezrl
10-01-2010, 01:42 PM
Not really. Oil from the pump also feeds directly to the oil cooler, as well as to the oil filter. There is an oil cooler thermostat in the oil filter housing adapter that prevents oil from passing through the oil cooler until it reaches a specific temp which is above normal driving temp. It operates much like the coolant thermostat except with a sliding sleeve valve.
Any air trapped in the oil cooler would "bleed" into the filter loop as the valve gradually opens & then on through the system as the valve cracks open. it is not a snap close-open-close valve. In all probability, air in the oil cooler loop probably bleeds around the sliding sleeve valve without it ever actually opening, allowing all air in the system to be processed out.
At this point, I'm not sure what's going on. If the oil filter was plugged for some odd reason, the oil filter bypass should/would open. For no pressure, the bypas would also have to be bad. Changing oil filters is certainly an easy & inexpensive test and logical next step.
Do you have a low oil pressure indicator light illuminated in the dash panel? If it is working (big question) it would illuminate. If low pressure and no light, it could be the sensor plug, sensor or the bulb in the panel not working.
The low oil pressure sensor is directly in the oil pump discharge circuit and would be the best indicator of oil pressure before all the cooler & oil filter valves. If the low oil pressure sensor weren't so hard to get to..... pulling it out & testing pressure there would definitely verify pump output.
Jerry, Thank you for the explanations some more things i learn about this motor. I retest the pressure this morning again same result. I don't have the low oil pressure warning on the dash panel. I will try to change the filter later and see it is the problem.
Shayne
shaynezrl
10-04-2010, 11:19 PM
Since you changed oil recently and since that oil change involved removal of the oil from the oil cooler (normally not done in an oil change), this is probably related to something other than oil pump.
Having said that.....I would at this point since you have run the engine on no oil pressure to the point of hearing lifters banging think about pressurizing the oil galley with fresh oil before I take another step in the diagnosis (without starting/running the engine).
I would remove the oil filter and pump oil into the engine to make sure every component (lifters, camshaft, cams, rods, main bearings) have a new fresh supply of oil (engine not running).
I'm in the process of checking things over. I will remove the oil pan this weekend and see if everything is in tack. Looking to see if anything might of came loose. The reason why i decide to drain the cooler was that i notice the old oil was really dark and wanted to have a clean fresh oil in the entire motor.
Is there a way to pump oil in the motor? How you do prime our motor with pump being in front?
thank you
Shaye
vandornjim
10-05-2010, 07:25 AM
Jerry, Thank you for the explanations some more things i learn about this motor. I retest the pressure this morning again same result. I don't have the low oil pressure warning on the dash panel. I will try to change the filter later and see it is the problem.
Shayne
Guys. This is yet another example of how an owner gets himslef into BIG trouble trying to do things he has no business doing.
Running an engine until it makes noise to test the oil pressure? NOT.
It gets louder when I rev it up
Oh boy. Anybody got an LT5 engine out there?
I added another 4 quarts to it after I ran it
The oil cooler holds 1 maybe 1 1/2 qts. Why drain it in the first place?
Good luck.
vandornjim
10-05-2010, 08:27 AM
The above statement is edited just a tad ;)
You talking about this Jim :sign10:
http://i287.photobucket.com/albums/ll142/dynomite007/90%20Corvette/90cutout.jpg
"Hey Jim, I thought I heard a squeaking noise somewhere on the driver's side....":-D
http://i287.photobucket.com/albums/ll142/dynomite007/90%20Corvette/90cutout.jpg
That's the way we have to change the battery.
rhipsher
10-05-2010, 10:13 AM
Shayne if I were you I'd first talk to somebody who makes a living working on LT5's before you go any further. Call Corey Henderson http://hendersonperformance.com/ Or Mark Haibak. Otherwise your just pissing in the wind.
xlr8nflorida
10-05-2010, 11:29 AM
The oil cooler holds 1 maybe 1 1/2 qts. Why drain it in the first place?
I was under the impression that the oil cooler held 3 quarts if you let the lt-5 drain overnight, I get 9 quarts out.
Are you saying the other 1.5 quarts is hanging out in the block?
Is the capacity of the oil cooler only 1.5 quarts?
In a followup to that question, how often does that oil cooler cycle it's contents and get fresh oil. I believe it takes certain parameters.
shaynezrl
10-05-2010, 12:49 PM
Guys. This is yet another example of how an owner gets himslef into BIG trouble trying to do things he has no business doing.
Running an engine until it makes noise to test the oil pressure? NOT.
Oh boy. Anybody got an LT5 engine out there?
The oil cooler holds 1 maybe 1 1/2 qts. Why drain it in the first place?
Good luck.Jim, You are right I am no expert on these motor. I was just performing regular maintenance. Replacing new aluminum radiator, cleaning all the craps out of the radiator housing and removing the cooler to clean. Then finally changing the oil. I put everything back together and everything went back as it should. The car ran cooler and all the power was there nothing to worry about. I drove the car about a week.I parked the car for a couple of days then the following morning i went to start it, that is when i noticed the ticking and the oil pressure gauge was moving left to right then eventually went to zero then i gave it some gas thought it would go away or the chain rattle on the start. When i realize that it could be oil pressure issue i quickly turned it off. At this point i am sure the motor is fine no damage as of yet. I will get it check out as soon as i can. I wanna say thank you for everyone's input. I appreciate all your help.
Shayne
rhipsher
10-05-2010, 01:24 PM
Shayne! There are many guys on this site that have lots of knowledge and are very helpfull. But even they can only help you to a point. If all else fails give the experts a call.
vandornjim
10-05-2010, 02:44 PM
Shayne if I were you I'd first talk to somebody who makes a living working on LT5's before you go any further. Call Corey Henderson http://hendersonperformance.com/ Or Mark Haibak. Otherwise your just pissing in the wind.
Yeah, whatver you do you don't want to give 'ol Van Dorn a shout. He's no expert, he's just been around since day one. :)
From AB26
Oil from the pump also feeds directly to the oil cooler, as well as to the oil filter. There is an oil cooler thermostat in the oil filter housing adapter that prevents oil from passing through the oil cooler until it reaches a specific temp which is above normal driving temp. It operates much like the coolant thermostat except with a sliding sleeve valve.
OK Shayne, listen up. Please don't run your engine ever again until you find the problem OK? I hate to see a guy get all messed up as a result of too many experts. :wave:
LT5 Oiling System 101
There is a sensor in the oil pan on some model years (MY) that detects low oil level. This has nothing to do with oil pressure. There is a sensor under the front of the right hand cam cover which is fairly well hidden. This is the ECM's oil pressure sensor. It tells the ECM whether you have pressure above the minimum requirments. If not, the "CHECK GUAGES" lite will appear. There is also a duplicate sensor located on top of the oil filter housing. This is for your guage. This is also known to leak, and get filled with oil into the electrical cavity causing it to malfunction.
Asise from all the talk about the filter housing and what it contains, that is not your problem unless you had it off and got something into it. Now.
The LT5 oil pump is a monster of a pump. It doesn't just "go bad". It has a huge rotor inside of it that will mix concrete if need be. :jawdrop:
So let's get down to the problem, shall we?
Down on the very front right side of the engine is a small plate held on by just 2 small (8mm) screws. It also has a gasket on it. This is known as your OPRV or Oil Pressure Regulating Valve. What this does is help control the oil pressure to the engine. When the oil is cold and the engine is first started, it develops enough oil pressure to not only blow the filter over your house, but it can also damage the cooler and other components as well. So, this valve actually moves and allows oil to flow directly BACK INTO THE PAN on startups. There is spring tension that moves the valve depending on the pressure. As the engine oil heats, it thins down and more oil is then allowed to go through the engine.
YOu also have to remember that the LT5 has to be able to idle, then go to 7200 rpms in a heartbeat. So, when you're out there hotrodding that engine at 7,000, the PRV may also direct excess oil into the pan.
Just for giggles, if you wanted to increase your oil pressure for whatever reason, you could do so by changing the spring tension of the PRV.
Now. What I suspect has happened is your PRV has gotten some junk in it or allowed to run without oil lubrication and it has become stuck in it's galley. YOU DO NOT HAVE OIL PRESSURE. So, the valve needs to be removed and checked to see if it travels smoothly. If it does not, there is a procedure to remove the valve and inspect it. First there is a snap ring to be removed. Then there is a special tool that only the "experts" have :icon_scra that we call a "dog d^ck". It has a larger head on it that goes into the center of the valve and then allows you to pull the whole valve out easily.
If it comes out hard or binds, then it is a good indication it has malfunctioned.
Anyway, that's all I know. But who am I? :p
rhipsher
10-05-2010, 02:58 PM
Yeah, whatver you do you don't want to give 'ol Van Dorn a shout. He's no expert, he's just been around since day one. :)Oh yeah and Jim Van Dorn to.:mrgreen:
vandornjim
10-05-2010, 03:13 PM
Oh yeah and Jim Van Dorn to.:mrgreen:
Ahhh shucks....:redface:
shaynezrl
10-05-2010, 10:00 PM
Mr. Jim Van Dorn, you have my respect. I did not know there was so many components involve with this engine design. Thank you for taking the time to share this. You hit it on nail when you said my gauge show (CHECK GAUGES). Thats was it showed that morning. The motor haven't start since then. I will not do so until i fine out the reason why? You given me another answer to the problem. You don't know how relief i am.
thank you
Shayne
vandornjim
10-06-2010, 07:08 AM
Mr. Jim Van Dorn, you have my respect. I did not know there was so many components involve with this engine design. Thank you for taking the time to share this. You hit it on nail when you said my gauge show (CHECK GAUGES). Thats was it showed that morning. The motor haven't start since then. I will not do so until i fine out the reason why? You given me another answer to the problem. You don't know how relief i am.
thank you
Shayne
Last time someone called me "Mr" it cost me a lot of money....:)
Picture of said "dog d^ck" :icon_scra
vandornjim
10-07-2010, 10:59 AM
Picture of said "dog d^ck" :icon_scra
I sent pics of "said Dog D^ck" to FU2 to post here.
http://i172.photobucket.com/albums/w37/furbo_2007/DSC06341.jpg
http://i172.photobucket.com/albums/w37/furbo_2007/DSC06339.jpg
vandornjim
10-09-2010, 10:38 AM
The above edited just a tad ;)
Where in the picture do the two 8mm screws fit? Is the plate that covers the oil pressure regulating valve which you remove circular?
Do you have a picture of the Oil Pressure Regulating Valve removed?
Any new information?
The cover and scfrews are not in the picture. They are attached to the engine block covering the PRV. After they are removed, there is a snap ring that holds the prv in. Aftrer removal of the snap ring, the tool is inserted into the small hole of the prv. Using the thumb screw and the plate, your can tighten the tool and removev hte prv if it is snug. SOmetimes they come out very easy.
"Said Dog D^ck".
shaynezrl
10-09-2010, 11:22 AM
Sorry guys i haven't got anytime to start working on the car. I have been busy with family. I should have sometime by next week. I can't wait to see what i fine.
Thank you Jim and FU for that pic of Dog D*ck very interesting tool. Hopefully i can fine something similar to get work on the OPRV.
Shayne
Chris_32212
10-15-2010, 09:38 PM
very interesting information about the that valve. I have an LT5 that is ticking for a min or two after WOT at very High RPM's and the knock/tick then goes away. maybe caused by something like this. I have a seperate thread posted here for people that would like a little more information about what the motor is doing and how my car is set up.
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