Any idea what is making this noise on my 1998 v8?

[Xylene]

My daughter was driving the car on the freeway when she noticed she couldn't get it past 60mph. When we got it home I noticed it making this sound. Any suggestions?

Microsoft OneDrive

1drv.ms

 

[EB4X]

No video link on your post...

 

[Xylene]

My daughter was driving the car on the freeway when she noticed she couldn't get it past 60mph. When we got it home I noticed it making this sound. Any suggestions?

​

No video link on your post...

Apparently I can't post video. I edited the post with a link to them

 

[C420sailor]

That knocking coupled with oil pressure out of limits near idle doesn’t bode well. I’d get an external pressure gauge on it, myself.

Mileage?

 

[Xylene]

No video link on your post...

I also can't seem to post a link

Microsoft OneDrive

1drv.ms

That knocking coupled with oil pressure out of limits near idle doesn’t bode well. I’d get an external pressure gauge on it, myself.

Mileage?

The engine was recently rebuilt, but the new radiator failed and pulled transmission fluid through the coolant system and vice versa. I was planning on pressure testing it this weekend. There are no engine lights on, oil levels are good.

 

[Xylene]

I also can't seem to post a link

Microsoft OneDrive

1drv.ms

The engine was recently rebuilt, but the new radiator failed and pulled transmission fluid through the coolant system and vice versa. I was planning on pressure testing it this weekend. There are no engine lights on, oil levels are good.

The radiator was fixed and I had to rebuild the transmission.

 

[Mbrooks420]

Don’t run, and especially rev a motor with no oil pressure. So much for those new bearings.

 

[toypaseo]

Kinda sounds like when a company work truck I drove ran low on oil. A co-worker said it's the bearings. That truck is now going up for auction sometime.

 

[CDW6212R]

My daughter was driving the car on the freeway when she noticed she couldn't get it past 60mph. When we got it home I noticed it making this sound. Any suggestions?

Microsoft OneDrive

1drv.ms

I don't see any mention of low oil pressure. Assuming the oil pressure light has not come on, check the balancer.

How old is the balancer, and if new what brand is it? The OEM or cheaper balancers can come apart at the rubber seam between the inner and outer ring. If the balancer slips, it can cause serious vibrations and roughness etc. Get under it and look closely at the balancer, see how the seam looks, and if the pulley is in line with the others(in/out).

EDIT, that's a shame, to see the oil pressure gauge drop to zero. That's a big problem, being rebuilt I wonder what caused that.

 

[Mbrooks420]

The oil pressure gauge clearly drops to zero several times during the video.

 

[CDW6212R]

Okay, I only watched the two video's that matched the link picture, of the engine bay. If the pressure is that low, the engine is hurt and with that noise, it'll have to come out again. It's a shame to hear that, it's a huge deal to R&R and engine, and to rebuild one. I don't want to do it in a hurry or due to a failure, but the engine building part I look forward to.

I'm going to need a rebuilt 302 in the next year or two, maybe one for my Mountaineer also. I've seen a recent stroker kit that is not much over $500 above a 302 built with a $500 Wiseco piston. I wouldn't build one as stock, or with low level pistons(that run $300+ alone anyway). So an extra $500ish is cheap money to gain 40 CI, besides the required custom computer tune also.

So if you build one, consider making it a 347 and have it properly tuned.

 

[EB4X]

On this part >> "but the new radiator failed and pulled transmission fluid through the coolant system and vice versa."
I've heard of this happening more than once now that basically ALL radiators are produced overseas / cheapo's ..........subpar materials / processes...

 

[Xylene]

On this part >> "but the new radiator failed and pulled transmission fluid through the coolant system and vice versa."
I've heard of this happening more than once now that basically ALL radiators are produced overseas / cheapo's ..........subpar materials / processes...

There is a single o-ring that keeps this from happening, and it seems that if the radiator isn't assembled well this can fail when the transmission line is connected and tightened on the radiator.

 

[Mbrooks420]

When installing a new radiator I’d bypass the radiator cooling loop for the transmission fluid, unless I lived somewhere extremely hot or cold.

 

[Xylene]

When installing a new radiator I’d bypass the radiator cooling loop for the transmission fluid, unless I lived somewhere extremely hot or cold.

I had the transmission rebuilt and the shop that did it suggested an external cooler. I might still go that route. I have had the car for 23 years with out a single problem and then an single piston ring went out (which caused the engine rebuild) Then a little while later the original radiator cracked and was replaced with a new one that didn't even last 500 miles. It has been nothing but problems since.

 

[Mbrooks420]

There still are plenty of quality radiators made, they just aren’t cheap, unfortunately.

 

[1998Exp]

There still are plenty of quality radiators made, they just aren’t cheap, unfortunately.

I can certainly understand the transmission damage from coolant, but how did the transmission fluid mixed in the coolant damaged the engine bearings? Can anyone can explain that?

 

[Mbrooks420]

I can certainly understand the transmission damage from coolant, but how did the transmission fluid mixed in the coolant damaged the engine bearings? Can anyone can explain that?

It wouldn’t, I was thinking it got into the engines oil.

 

[Xylene]

It wouldn’t, I was thinking it got into the engines oil.

Does anyone know what transmission fluid going through the coolant system might do to the gaskets?
As far as the oil pressure gauge, I am not sure it is functioning correctly. When checking the oil levels they are all normal and the oil is clean. Would the gauge indicate some other problem that manually checking the oil wouldn't show?

 

[CDW6212R]

The ATF in the cooling system is minor and it won't harm any gaskets. You should have flushed the cooling system when the radiator was replaced, to remove the residual ATF, but it's not a terrible thing.

The oil pressure gauge is an ON/OFF device. It reads zero when the oil pressure is below a dangerous level such as 5-10psi. So the pressure sensor in the side of the engine is only producing a signal to the gauge when the pressure is adequate, above 10psi etc. If your oil gauge reading is right, the pressure is dropping dangerously low, often.

It would help to confrim the pressure is low, with a separate gauge and sensor, or by replacing the OEM sensor, and maybe the gauge if that is also suspect. But be prepared to need to pull the engine back out, the pump or the pickup may be not right, or some other internal issues(too large bearing clearances etc).