98 GT making loud ticking noise

[Flade]

Drove my wife’s 4.6L 98GT to work today. Halfway there it started making strong ticking/clattering noise. Definitely a mechanical sound, matches engine RPM. It is running a bit rough. I used a mechanics stethoscope and can’t localize the noise. Seems to be loud at the top but balanced equally side to side. If it was a pushrod engine I’d say the rockers were loose.

It’s got 211K miles on it. I replaced the cam tensioners a few years ago (maybe 20k miles). 2 months ago I swapped the heads with a pair of low mileage rebuilt PI heads and a PI manifold. Tensioners looked perfect so I didn’t replace them.

Pulled the codes and it shows a misfire on 1 & 8.. Up to now it’s been running great.

I’ve got a video of it, but can’t figure out how to post.

Is there anyway to narrow down the potential cause? Hoping I didn’t spin a bearing or anything else catastrophic, but I can’t think of what else it could be.

Thoughts?

 

[RAU03MACH]

you tube video would be the best way
record
in your gallery find video hit the share button
look for you tube select let it load
once finished
select share on that video to up load on files
attach files

 

[96blak54]

Chain tensioners, chain guides, or lash adjusters would be my guess. Lash adjusters can play havoc if failed or oil psi not correct at the lashers. Clogged oil galleries restricting oil volume to said components.

Do you hear this noise at idle and then fades away as rpm increase? Try to figure out what rpm the noise fades away at. The chain tensioners have 100% of oil pump supply and is orificed within the tensioner.

The lashers is orifice at the larger cam bearing cap. The lasher gallery might hit 15psi at high rpm and the supply is minimal compared to the rest of the engine.

 

[ttocs]

it could be a bad coil/plug wire, they will make a tick/arcing sound each time the cylinder fires. Sometimes if you look at it at night you will see the flash but otherwise you can easily diagnose it by grabbing the wires and seeing if they shock you or if anything changes.

 

[highplace11]

Post a video please ...

Mark

 

[Flade]

Chain tensioners, chain guides, or lash adjusters would be my guess. Lash adjusters can play havoc if failed or oil psi not correct at the lashers. Clogged oil galleries restricting oil volume to said components.

Do you hear this noise at idle and then fades away as rpm increase? Try to figure out what rpm the noise fades away at. The chain tensioners have 100% of oil pump supply and is orificed within the tensioner.

The lashers is orifice at the larger cam bearing cap. The lasher gallery might hit 15psi at high rpm and the supply is minimal compared to the rest of the engine.

It’s a light tick at idle then builds. It seems quiet at a higher ROM, but it could just be gettiing drowned out. What could use the lash adjusters to start acting up? Restriction in oil flow? How do I check and fix them if that is the problem.

 

[Flade]

you tube video would be the best way
record
in your gallery find video hit the share button
look for you tube select let it load
once finished
select share on that video to up load on files
attach files

thanks that helped.

Here is the video

 

[RAU03MACH]

if you can get the valve covers off
run it do not rev it
and video it its going to be a little messy put card board on the ground under engine
mostly top end

 

[ttocs]

that sounds bad.....

 

[Flade]

if you can get the valve covers off
run it do not rev it
and video it its going to be a little messy put card board on the ground under engine
mostly top end

I was thinking the same thing. It sounds like the lash adjusters are not pumping up. Just like old style lifters. Which makes me wonder if oil pressure is low. Is there a good spot to install an oil pressure gauge and see what the pressure is really doing?

 

[96blak54]

Most definitely gonna have to remove a valve cover for that one.

Remove cover, look for bigger cam cap, only remove that single cap.

This picture may look like yours, may not, but will be same idea.

1st pic red arrow is oil psi supply from the block and its 100%. The orange arrow hole, lasher feed, is feed by the oil psi supply, but is not 100%. It is orificed by a tiny notch located on the cam cap represented by the teal/black arrow 2nd picture

Notice cam cap 2nd picture. Green/white arrow is cavity for oil psi from block. Teal/black arrow is orifice notch. Black/white arrow is cavity of lasher supply hole.

Lets focus on the orifice notch of cam cap. That notch could be clogged. Ive seen sludge, rtv, bits of fabric, and plastic shreds blocking supply to the lasher feed hole.

Checking this will be a good start.

 

[Flade]

Most definitely gonna have to remove a valve cover for that one.

Remove cover, look for bigger cam cap, only remove that single cap.

This picture may look like yours, may not, but will be same idea.

1st pic red arrow is oil psi supply from the block and its 100%. The orange arrow hole, lasher feed, is feed by the oil psi supply, but is not 100%. It is orificed by a tiny notch located on the cam cap represented by the teal/black arrow 2nd picture

Notice cam cap 2nd picture. Green/white arrow is cavity for oil psi from block. Teal/black arrow is orifice notch. Black/white arrow is cavity of lasher supply hole.

Lets focus on the orifice notch of cam cap. That notch could be clogged. Ive seen sludge, rtv, bits of fabric, and plastic shreds blocking supply to the lasher feed hole.

Checking this will be a good start.

View attachment 38555

Thanks, that gives me a good place to start looking.

 

[RAU03MACH]

also visually inspect while engine is running to determine where noise is the most

 

[Flade]

Well good new and bad news….

Good news: I don’t think the engine is trashed.
Bad News: I think the PI heads are.

I got back under the hood with the stethoscope. After listening around I was able to determine that the noise was definitely coming from the driver’s side head. I figured this confirmed an oil feed problem to the lash adjusters. Following the great guidance from 96blak54, I pulled off the drivers valve cover. Everything looked normal. then I removed the cam retainers as he described to check for anything plugging up the oil ports. Oh Oh….the bolts were not properly torqued…damn some were only finger tight.

I pulled the retainer off and the ugliness reared its head. The cam journals and the journals on the retainer are both scored.

Time to kick myself at least twice for not checking that they were properly torqued.

When I bought the heads I was told that they had been rebuilt and installed on a motor, then after only a couple thousand miles the owner pulled them for aftermarket heads in search of more HP.
Other than a little oil on them they looked brand new so I have not reason to doubt what I was told. I got them cheap too. since they were removed from a running engine, I never even looked at the cam. They heads have been wrapped and sealed since I bought them.

What I now believe is that the owner had been running aftermarket cam, and when he pulled the heads he swapped the original OEM cams back in and just finder tightened them. Then stupidly I forgot to double checked they were properly torqued when I installed them.

I suspect that without them being torqued they began to work loose until the oils started squirting out between the retainer and he’d instead of pressurizing the lash adjusters…And then the noise began!

Hard to say if the cams were damaged before I got them, ran dry of oil or weren’t clean when dropped back into the heads. Probably no way to know. In any case, I need at least 1 new head and cam and more expensive Torque to yield bolts! I don’t seen any since of metal in the oil so hopefully the rest of the engine is OK. I’ll have to pull the 2nd cover and see if it is damaged too.

 

[SlograbDC]

Well, shit - glad it isn't anything *worse* at least - luckily, PI heads aren't prohibitively expensive

I would definitely do an oil change alongside that

 

[Flade]

Well, shit - glad it isn't anything *worse* at least - luckily, PI heads aren't prohibitively expensive

I would definitely do an oil change alongside that

The parts to do the change (gaskets, bolts, dipstick tube, etc.) cost as much as a set of used heads. It’s the PITA to do these swap in the car. But since I just put them in 2 months ago, I have plenty of practice. The dipstick tube was actually the hardest part of the swap…..what a terrible design….

 

[Slice]

I know you found the source of the ticking noise but I would like to share my experience with others. It was actually a V6 on my boat and it sounded like a lifter ticking. Pulled the upper parts off and it looked fine so finally pulled the whole engine out of the boat. The Pistons and cylinders looked good from above but when I pulled the oil pan and looked up from the crankshaft I could see one cylinder black and badly scored. When I pulled that particular piston out I could see it was burned. So sometimes I ticking noise can mean a collapsed piston.

 

[BHernandez]

Drove my wife’s 4.6L 98GT to work today. Halfway there it started making strong ticking/clattering noise. Definitely a mechanical sound, matches engine RPM. It is running a bit rough. I used a mechanics stethoscope and can’t localize the noise. Seems to be loud at the top but balanced equally side to side. If it was a pushrod engine I’d say the rockers were loose.

It’s got 211K miles on it. I replaced the cam tensioners a few years ago (maybe 20k miles). 2 months ago I swapped the heads with a pair of low mileage rebuilt PI heads and a PI manifold. Tensioners looked perfect so I didn’t replace them.

Pulled the codes and it shows a misfire on 1 & 8.. Up to now it’s been running great.

I’ve got a video of it, but can’t figure out how to post.

Is there anyway to narrow down the potential cause? Hoping I didn’t spin a bearing or anything else catastrophic, but I can’t think of what else it could be.

Thoughts?

Check the vacuum hose from the EGR to the EGR pressure sensor. Sometimes they wear out or burn against the head. It makes a bad ticking noise like an exhaust leak and make the tune run lean.