Rattling sound while accelerating?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

chengny

Full Access Member
Joined
Feb 22, 2012
Posts
4,086
Reaction score
1,008
Location
NH
First Name
Jerry
Truck Year
1986
Truck Model
K3500
Engine Size
350/5.7
Any gauge is fine - there's no such thing as oil specific pressure gauge. You don't have to order it either.

Home Depot keeps this gauge on the shelf and in stock:

You must be registered for see images attach


Model # M1002-8B Internet # 203990005

100 psi Pressure Gauge with 1/8 in. Back Connection

It's like $6.

But rather than worrying about where to buy a gauge, can I suggest that you first find out where you can easily tap into the oil system. Find a port that is visible and also allows you to physically get a gauge into it.

I know I initially suggested that you locate the sender - and use that port to install a gauge, but that isn't the only option. And, you don't have to pull the sender if you find an easier place to stab the gauge.

Check out block, in the area above the oil filter. You should notice a series of holes in the casting. I can't provide much insight on 454's so you're on your own this but; I looked around and it seems like 2 of them are oil ports and can be used to install a gauge.

You must be registered for see images attach


The sizes of the holes is apparently a mystery - even to most of the folks who run these engines. But anyway, your best bet might be to see if you can even pull the plugs from either one - or both - of the two ports.

If you can access either port (or both) that will determine the NPT size of the gauge you buy.
 

hambo

Full Access Member
Joined
Dec 11, 2014
Posts
92
Reaction score
0
Location
illinois
First Name
Ian
Truck Year
1987
Truck Model
k20
Engine Size
454
Any gauge is fine - there's no such thing as oil specific pressure gauge. You don't have to order it either.

Home Depot keeps this gauge on the shelf and in stock:

You must be registered for see images attach


Model # M1002-8B Internet # 203990005

100 psi Pressure Gauge with 1/8 in. Back Connection

It's like $6.

But rather than worrying about where to buy a gauge, can I suggest that you first find out where you can easily tap into the oil system. Find a port that is visible and also allows you to physically get a gauge into it.

I know I initially suggested that you locate the sender - and use that port to install a gauge, but that isn't the only option. And, you don't have to pull the sender if you find an easier place to stab the gauge.

Check out block, in the area above the oil filter. You should notice a series of holes in the casting. I can't provide much insight on 454's so you're on your own this but; I looked around and it seems like 2 of them are oil ports and can be used to install a gauge.

You must be registered for see images attach


The sizes of the holes is apparently a mystery - even to most of the folks who run these engines. But anyway, your best bet might be to see if you can even pull the plugs from either one - or both - of the two ports.

If you can access either port (or both) that will determine the NPT size of the gauge you buy.

Okay so I think I found where I can tap into the oil system to test my pressure. I found a fitting thats shaped like an L with a wire coming out each end of the L shape. Its right above the front corner edge of the oil pan on the drivers side. this is a picture of it:


If my oil pressure is indeed very low, as in like below 10 psi, then could that be the cause of all these problems? the rattling and the suspected detonation? Even if the engine wasnt overheating?
 

Attachments

  • IMAG1881_1.jpg
    IMAG1881_1.jpg
    92.2 KB · Views: 69

chengny

Full Access Member
Joined
Feb 22, 2012
Posts
4,086
Reaction score
1,008
Location
NH
First Name
Jerry
Truck Year
1986
Truck Model
K3500
Engine Size
350/5.7
If my oil pressure is indeed very low, as in like below 10 psi, then could that be the cause of all these problems? the rattling and the suspected detonation? Even if the engine wasnt overheating?

If your oil pressure is under 10 psi and has already developed a knock, it may mean that you are looking at a rebuild. Don't even think about that right now - it'll just bum you out.

Get a gauge hooked up and see what your oil pressure is.
 

hambo

Full Access Member
Joined
Dec 11, 2014
Posts
92
Reaction score
0
Location
illinois
First Name
Ian
Truck Year
1987
Truck Model
k20
Engine Size
454
If my oil pressure is indeed very low, as in like below 10 psi, then could that be the cause of all these problems? the rattling and the suspected detonation? Even if the engine wasnt overheating?

If your oil pressure is under 10 psi and has already developed a knock, it may mean that you are looking at a rebuild. Don't even think about that right now - it'll just bum you out.

Get a gauge hooked up and see what your oil pressure is.

Okay. Thanks. Yeah I will saturday. Do you know by chance if oil will burst out of that hole? I assume a little may come out but im hoping I dont have to keep it plugged because I want to bring the part to Homedepot to make sure I get the right size fitting. And should I be okay to unplug the two wires that are going into the L shaped metal piece thats screwed into the block? Is the picture of the piece I posted the oil sender? Thanks again for all the help everybody.
 

GTME94

Full Access Member
Joined
Jan 20, 2013
Posts
441
Reaction score
31
Location
Metro Detroit/Holland, MI
First Name
Terry
Truck Year
86
Truck Model
C2500 C6P Camper Special
Engine Size
454/TH400/14bff 3.73
Yes that L shaped fitting is where to tap into for the oil pressure. Your picture shows the fitting and the two pressure senders. One of the senders is pointing straight out towards the frame, the other is pointing down. Some oil will drain out but not be pressurized (unless the engine is running:)). You won't have to undo the actual L shaped fitting. You will be undoing one of the pressure senders with the wires that is screwed into that brass fitting. Unplug the wires from the sender. There will be a place to put the wrench on the end of the fitting to unscrew it. Then take the sender with you to match the thread size.

I say to only undo one of the pressure senders because to remove the L shaped fitting you'd have to remove both pressure senders to get the fitting to unscrew from the block. If the senders are left in they hit the frame and power steering lines and won't allow the fitting to rotate.
 
Last edited:

hambo

Full Access Member
Joined
Dec 11, 2014
Posts
92
Reaction score
0
Location
illinois
First Name
Ian
Truck Year
1987
Truck Model
k20
Engine Size
454
Any gauge is fine - there's no such thing as oil specific pressure gauge. You don't have to order it either.

Home Depot keeps this gauge on the shelf and in stock:

You must be registered for see images attach


Model # M1002-8B Internet # 203990005

100 psi Pressure Gauge with 1/8 in. Back Connection

It's like $6.

But rather than worrying about where to buy a gauge, can I suggest that you first find out where you can easily tap into the oil system. Find a port that is visible and also allows you to physically get a gauge into it.

I know I initially suggested that you locate the sender - and use that port to install a gauge, but that isn't the only option. And, you don't have to pull the sender if you find an easier place to stab the gauge.

Check out block, in the area above the oil filter. You should notice a series of holes in the casting. I can't provide much insight on 454's so you're on your own this but; I looked around and it seems like 2 of them are oil ports and can be used to install a gauge.

You must be registered for see images attach


The sizes of the holes is apparently a mystery - even to most of the folks who run these engines. But anyway, your best bet might be to see if you can even pull the plugs from either one - or both - of the two ports.

If you can access either port (or both) that will determine the NPT size of the gauge you buy.

I am planning on getting the home depot gauge you posted. What kind of hose/tubing should i use between the connection at the gauge and the block? diameter? does material matter? and does the length of the hose matter or affect the pressure reading at all? Is any length good? just want to make sure im getting the most accurate reading possible. Thanks.
 

chengny

Full Access Member
Joined
Feb 22, 2012
Posts
4,086
Reaction score
1,008
Location
NH
First Name
Jerry
Truck Year
1986
Truck Model
K3500
Engine Size
350/5.7
I have no idea about what kind of space restrictions you are dealing with - so it's hard for me to offer specific information on the fittings you'll need.

But, from what I can see in the image you posted, this shouldn't be too hard. First do as Terry suggests and remove the sender. The sender is the bell shaped sensor and the switch is the other one (it's shape is hard to describe). Here is the difference:

You must be registered for see images attach


With the sender removed you will have a tee with the open port facing outward -towards the frame rail. If you are planning on using the gauge shown above you will also need a 90 and a closed nipple. This is because the gauge above is back connected. If you were to screw it directly into the tee, the face would be right up against the frame and vertical. This configuration would make the gauge unable to be viewed.

So do this: Pull the sender, screw a closed nipple into the tee and then thread a 90 onto the nipple (and have the open port of the 90 facing up). So then, when you install your back-connected gauge , it will be facing up. You will be able to check the oil pressure by just leaning over the fender and looking down. If you wanted, you could also buy a longer nipple (maybe 6" or so) and a coupling to raise the gauge up a bit for better visibility. The long nipple would screw into the 90, the coupling would go onto the top of the nipple and the gauge would thread into the coupling.

BTW - all these fittings will be 1/8" NPT and can be steel (there is no need to buy brass fittings). You might want to pick up a roll of teflon tape as well - you don't want to deal with leaks during the test.

As far as whether the gauge will provide an accurate indication of the actual oil pressure - because of the length of the connected piping:

Not an issue. Your gauge will be less than a foot from the pressure source. When (if?) engine oil pressure is established, the air in the lines will quickly compress and the gauge will react accordingly. This will take less than a couple of seconds.

Bear in mind that this check of the oil pressure should not take long at all. Once the engine is started, the oil pump should develop pressure within the galleries immediately. If after 10 seconds, there is no pressure indicated on the gauge...shut down. The motor cannot be run and will at least need a new oil pump - but probably a lot more.

If you do see oil pressure on the gauge , you can watch it to make sure it stays up as the oil gets warm.

Good luck man - I'm sure everyone watching this thread hopes that you show oil pressure - and that your engine isn't shot.
 
Last edited:

hambo

Full Access Member
Joined
Dec 11, 2014
Posts
92
Reaction score
0
Location
illinois
First Name
Ian
Truck Year
1987
Truck Model
k20
Engine Size
454
Bad news. I didn't get any reading on my gauge. I bought a 300psi air pressure gauge from HD, a 90 elbow, a 4inch extension, and a 1/8 to 1/4 converter threads. I tefloned everything, and screwed it into where the sending unit was and nothing. The gauge was facing down at an almost 90° angle. Could that have caused it? Did I do something wrong? When I took the sender out without the engine running the first time only a few small drizzles came out. But then my new gauge had some oil in it. Did I do something wrong?! I really don't want to have to rebuild this thing!
 

Skweegle89

Full Access Member
Joined
May 21, 2014
Posts
2,347
Reaction score
25
Location
Oklahoma
First Name
Zach
Truck Year
1985
Truck Model
K10
Engine Size
350
Not a good sign man. Especially with a cold engine.


Sent from my iPhone using Tapatalk
 

350runner

Full Access Member
Joined
Feb 9, 2013
Posts
2,858
Reaction score
224
Location
tx
First Name
Ceasar
Truck Year
82
Truck Model
c10
Engine Size
350
Well I would start by replacing the oil pump :)... It should be simple as the nylon bushing broke. This would be the first step of process of elimination. If this shores not provide better oil pressure well......:-(

Sent from the dust in front of you!
 

chengny

Full Access Member
Joined
Feb 22, 2012
Posts
4,086
Reaction score
1,008
Location
NH
First Name
Jerry
Truck Year
1986
Truck Model
K3500
Engine Size
350/5.7
At this point, forget about the gauge. Just pull the sender - and leave the port it screws into open. Start the engine and see if any oil flows from the tee at all.

Excluding the catastrophic cases like thrown rods, bent crankshafts, etc. There are basically two types of engine failure. They both are related to bearing damage but there is a big fundamental difference between the two.

One, the least harmful, is when the bearings are "wiped".

The other, which basically renders the block unusable without extensive machine work (i.e. line boring) is when the bearings are "spun".

If an engine is operated without a constant supply of cool oil to its bearings - for more than a short time - the oil film between the moving parts overheats and breaks down.

Without that film of oil to separate the rotating steel journals from the stationary surfaces of the bearings, metal-to-metal contact quickly begins to take place. Depending on how long this contact is allowed to continue, the babbited surfaces of the bearings will heat up and melt. Eventually the melted babbit will start to be wiped away by the motion of the rotating journals (hence the term "wiped bearing").

At this point the bearings are ruined but the engine can be salvaged. The bearings are designed to be replaceable without any machine work. Whether the crankshaft is reusable as is, needs to have the journals surfaced, or is just trash - is determined by the degree of damage that the journal surfaces suffered.



Now comes the worst part:

If the oil film is lost and metal-to-metal contact is established, damage to the bearing and journals begins immediately. If the engine is not stopped (or by some miracle, oil flow is re-established) the bearing and journal soon become so hot - due to friction - that they will actually be welded together.

When they are welded together, and if the crankshaft continues to rotate, the bearing shell breaks free from the machined grooves in the bearing cap/block and begins to rotate along with the journal. When this happens, the bearing inserts are literally spinning within the bearing caps/block bore (hence the term "spun bearing").

If the bearings inserts spin within the bearing cap/block bore for even a brief time, the back sides (of the bearing inserts) will grind against the block and alter the dimensions/seating surface of the bore.


Point of all this is that - if you haven't operated the engine without oil for too long - there is a chance that you may not have spun any bearings. If that is the case, the engine can be rebuilt without any machine work.
 
Last edited:

350runner

Full Access Member
Joined
Feb 9, 2013
Posts
2,858
Reaction score
224
Location
tx
First Name
Ceasar
Truck Year
82
Truck Model
c10
Engine Size
350
:)

Sent from the dust in front of you!
 

Skweegle89

Full Access Member
Joined
May 21, 2014
Posts
2,347
Reaction score
25
Location
Oklahoma
First Name
Zach
Truck Year
1985
Truck Model
K10
Engine Size
350
I'm curious as to what your main caps look like. Mine was running like yours when I pulled it and my caps were solid copper. The only reason it didn't leave me stranded is that it never really got hot. I just drove it a couple blocks at a time.


Sent from my iPhone using Tapatalk
 

hambo

Full Access Member
Joined
Dec 11, 2014
Posts
92
Reaction score
0
Location
illinois
First Name
Ian
Truck Year
1987
Truck Model
k20
Engine Size
454
At this point, forget about the gauge. Just pull the sender - and leave the port it screws into open. Start the engine and see if any oil flows from the tee at all.

Excluding the catastrophic cases like thrown rods, bent crankshafts, etc. There are basically two types of engine failure. They both are related to bearing damage but there is a big fundamental difference between the two.

One, the least harmful, is when the bearings are "wiped".

The other, which basically renders the block unusable without extensive machine work (i.e. line boring) is when the bearings are "spun".

If an engine is operated without a constant supply of cool oil to its bearings - for more than a short time - the oil film between the moving parts overheats and breaks down.

Without that film of oil to separate the rotating steel journals from the stationary surfaces of the bearings, metal-to-metal contact quickly begins to take place. Depending on how long this contact is allowed to continue, the babbited surfaces of the bearings will heat up and melt. Eventually the melted babbit will start to be wiped away by the motion of the rotating journals (hence the term "wiped bearing").

At this point the bearings are ruined but the engine can be salvaged. The bearings are designed to be replaceable without any machine work. Whether the crankshaft is reusable as is, needs to have the journals surfaced, or is just trash - is determined by the degree of damage that the journal surfaces suffered.



Now comes the worst part:

If the oil film is lost and metal-to-metal contact is established, damage to the bearing and journals begins immediately. If the engine is not stopped (or by some miracle, oil flow is re-established) the bearing and journal soon become so hot - due to friction - that they will actually be welded together.

When they are welded together, and if the crankshaft continues to rotate, the bearing shell breaks free from the machined grooves in the bearing cap/block and begins to rotate along with the journal. When this happens, the bearing inserts are literally spinning within the bearing caps/block bore (hence the term "spun bearing").

If the bearings inserts spin within the bearing cap/block bore for even a brief time, the back sides (of the bearing inserts) will grind against the block and alter the dimensions/seating surface of the bore.


Point of all this is that - if you haven't operated the engine without oil for too long - there is a chance that you may not have spun any bearings. If that is the case, the engine can be rebuilt without any machine work.
So now, what should I do? Im in highschool, and only have about $500 to my name after buying the truck. I have very limited mechanical knowledge. I am taking autos classes and have learned some, but I feel it isn't enough to rebuild an engine. Right now I feel like I should pull the pan, check the pickup screen, and if thats clear, then I'll replace the pump and run it and see if it improves. Would that be a good idea? I want to try that since I dont think I have the cash to rebuild the engine currently. Is this a good idea? Again, thank you everyone for all your help with this issue. This forum and all you guys have been a huge help, especially to someone like me with limited knowledge. Thank you.
 

chengny

Full Access Member
Joined
Feb 22, 2012
Posts
4,086
Reaction score
1,008
Location
NH
First Name
Jerry
Truck Year
1986
Truck Model
K3500
Engine Size
350/5.7
I would go like this:

Drain the engine's oil into a clean container - and note the presence (or lack of) shiny metal particulates.

If any metal is observed, determine whether it is ferrous (iron/steel based) or non-ferrous. Do this by dragging a magnet through the oil. Only ferrous particulates will stick to a magnet.

If the magnet comes out of the oil covered in small pieces of steel, the engine has suffered severe damage.

If the magnet comes up clean (or with just a minor amount of fine dust), that would indicate that the metal in the oil is non-ferrous. It can then be safely assumed that the metal flakes are just pieces of bearing material - that have been wiped away from the shells. In that case, there is a strong possibility that the block has not been damaged and the engine can be rebuilt.

To investigate further, you might want to pull the oil filter and cut it open. Dump the contents of the filter into a clean container and inspect. Also look at the "dirty side" of the filter pleats - look for any large pieces of metal.
 

Latest posts

Forum statistics

Threads
42,185
Posts
910,890
Members
33,678
Latest member
tnahaus
Top