Chasing that annoying 4V "Rattle"...again

[Wild Horses]

I've been doing a ton of searching and reading on this problem and it seems to be super common. I can find countless threads with "rattle between 2000-3000rpm" in the title. In my frustration I've read most of them and 90% have no fix and just deal w it. To clarify a little it sounds like a hollow very fast paint can rattle.

My 01 started the rattle after I rebuilt the engine with forged internals. The FIRST time I had the issue i could replicate the rattle revving outside the car and i could hear it briefly at startup. It would also be worse until the car warmed up and then it'd go away slightly. I ignored it until one 95* day this summer the drivers side secondary chain snapped in a third gear pull. Luckily (I have NO IDEA HOW) I didn't hurt any valves and/or Pistons. Believe me I checked and checked and ended up with a borescope down the intake runners and through the plug holes. It did wash out my cylinders on that side but I put tranny fluid in them and figure they'd be fine. I replaced my timing chains/tensioners/cam bolts and the curved tensioner guides with all Ford parts except the passenger side secondary which was a new MMR tensioner "flip" modification. Changed the oil and the noise was GONE. And I mean it was gone forever i thought. She ran her ass off once again.


Now it's back. Not nearly as bad and a little different. It started only after the Vortech install and very first start up with the base tune my tuner sent to get the car down to the dyno. It definitely did not rattle the day I pulled it onto the lift for install. I'm starting to think it's a pulley or the belt tensioner, but idk. I'd pull the belt and drive it but they're such a pain with the Vortech. I have the powercooler kit so the aluminum could be hitting the ac lines when the motor torques to the side. I just rebuilt the entire Vortech head unit because the front seal was leaking also. I AM however running that crappy dayco composite idler pulley that Vortechs part crosses over to. Oil pressure is up at 90psi at cold start, 30 at op temp idle, and 45-90 with throttle varyence so all is normal there.
This time the issue is only present in gear, under very light load, between 2k-3k, and at all driving temps. It's not as loud as the last ratttle but does have the same type of sound. If I lay on the gas a little more it's completely gone. Or if I start out anymore than 1/4 throttle I hear nothing until I shift gears I hear it as the motor winds down for a split second. The car is going on the dyno Friday morning no matter what. Hopefully it's just a timing issue within the tune. Lastly, I have a tube K member so I just pulled the oil pan off of the car to install the Vortech oil return line all rods were inspected.

Would anyone else agree this has to be something with the Vortech install? Can the tune alone cause a slight rattle?
Going to try and get a video posted up as well as some pics of the last repair and my Vortech install.
I WILL get to the bottom of this and post the exact cause and the FIX because there are so many unresolved rattles with these motors.

Anyone who has had this issue please post up your experience. Maybe we can start a thread with answers for those that are going crazy trying to track this down. Wow Sorry for the super long post, but I wanted to have as much detail as possible.

 

[lwarrior1016]

Could the tune be leaning out and causing a little bit of pinging at low throttle/low fuel situations? It could be something with the blower install but I think you would hear that more as you load the engine up.

Not to scare, but Im pretty sure the 4v's had issues with the valve guides being "loose" and causing some valve train noise.

If the car is running good, I would take it to the dyno on Friday and see what happens there. If the noise persists, then we can track it down further.

 

[chris91]

Ever replace the Lash Adjusters? Basically just like a lifter, when bad it sounds like that.

 

[96blak54]

Loose valve seats is a possibility. Also lasher issues like chris91 points out.

Your description mimics lasher issue. Cold rattle, warm it disappear, high rpm it fades away, comes back at low rpm. And your most likely running 5w-20 oil or less.

I can see a host of problems here. The biggest contributor is 32 lashers bleeding oil. Low rpm, the lashers bleed out and need pressured supply. At high rpm, the lashers still bleed the same but supply pressure is greater. Adding a supercharger oil supply further reduces the supply to thd heads.

The modular follower design is the beginning stages of veriable cam timing were the lashers acted different for the amount of supply applied. As rpm increased the supplied pressure cause lasher bleed down rates to changed into a more stiff/locked lasher. Low rpm isnt offering your heads the correct supply and adding the superchargers oil feed reduced the supply more.

At low rpm when the cam lobe swings around and applies pressure to both spring and lasher, one has to give. The lasher gives in first untill the hydraulic resistance over comes the spring rate and then the valve opens. When cam lobe ramps down, again the hydraulic and spring rate are at battle with each other untill the valve is shut. Now.....your oil supply pressure is supposed to push the lasher back, keeping this harmony together, but it dont. This is where rattle comes in.

 

[Wild Horses]

Loose valve seats is a possibility. Also lasher issues like chris91 points out.

Your description mimics lasher issue. Cold rattle, warm it disappear, high rpm it fades away, comes back at low rpm. And your most likely running 5w-20 oil or less.

I can see a host of problems here. The biggest contributor is 32 lashers bleeding oil. Low rpm, the lashers bleed out and need pressured supply. At high rpm, the lashers still bleed the same but supply pressure is greater. Adding a supercharger oil supply further reduces the supply to thd heads.

The modular follower design is the beginning stages of veriable cam timing were the lashers acted different for the amount of supply applied. As rpm increased the supplied pressure cause lasher bleed down rates to changed into a more stiff/locked lasher. Low rpm isnt offering your heads the correct supply and adding the superchargers oil feed reduced the supply more.

At low rpm when the cam lobe swings around and applies pressure to both spring and lasher, one has to give. The lasher gives in first untill the hydraulic resistance over comes the spring rate and then the valve opens. When cam lobe ramps down, again the hydraulic and spring rate are at battle with each other untill the valve is shut. Now.....your oil supply pressure is supposed to push the lasher back, keeping this harmony together, but it dont. This is where rattle comes in.

THIS has been another thought. I had to add almost a quart of oil to compensate for the blower supply and the extra bleed off into the blower trans could be just enough to bring that sound back. It DOES have a fast enough sound to be the 32 valves. When I built the motor I DID lap the hell out of the valve seats as well as port them flush with the aluminum and then a tiny bit more. Maybe when I did the lapping I wore the guides out? Idk. The car absolutely screams though. I mean.. as in a week before the blower install I was pulling car lengths on my buddies automatic 98 C5 with Texas Speed h/c/i. Maybe a set of supercar followers and new lash adjusters are the winters project. Hate pulling these valve covers.

If this is the case it should be alright for a little bit as long as they don't bleed any faster in heavier load or collapse during a hard pull. That would kinda suck...

But then again... wouldn't I hear bled out lashers at cold start up? You know the more I think about it the more I can picture one of the rollers making this sound. I wonder if I lapped the valves too deep leaving too much static pressure on the adjusters... It's so annoying. I've dumped so much money in this little 4.6 I coulda had a coyote swap by now.

 

[Wild Horses]

Could the tune be leaning out and causing a little bit of pinging at low throttle/low fuel situations? It could be something with the blower install but I think you would hear that more as you load the engine up.

Not to scare, but Im pretty sure the 4v's had issues with the valve guides being "loose" and causing some valve train noise.

If the car is running good, I would take it to the dyno on Friday and see what happens there. If the noise persists, then we can track it down further.

Id say its too high pitched to be any sort of pinging. It's happening with 10" of vacuum still in the intake as well. No boost at all. Im running decca 60s and areomotive 325lp so she's fueled pretty well. Valve guides don't really scare me... I'm more worried about piston slap or anything timing that I've already spent a butt load of money on. LOL I have a set of 04 9 threads that need rebuilt. Maybe I'll do those up instead.

Hell... maybe it's an ac line. I won't be able to pinpoint this until it's under load on the dyno. It's frustrating.

 

[Wild Horses]

Ever replace the Lash Adjusters? Basically just like a lifter, when bad it sounds like that.

I think doing this would be the most cost effective thing just to try out before I dig any deeper by pulling heads. When I did the rebuild they all seemed nice and clean and none were weak. The car had 60k miles at that point so I figured they'd be fine.

 

[96blak54]

The valves guides arent worn. Nor will they ever wear. If you say lapping the valve seats down .020" technically raises the valve stem up .020" moving the follower up more and engaging into the lasher more. Or in other words tightening up the valve train by sinking the valve deeper.....so I dont think thats it either.

The noise you hear really isnt any different than a solid lash setup, only yours will fade away. Although sloppy around low rpm, the high rpm oil pressure compensate the supply demand actuating the lasher hydraulic purpose.

Simple fix? Heavier oil, modify the head oiling orfice, shim the lashers some.

 

[Wild Horses]

Yea i get what you're saying. I was kind of thinking in terms of more load on the followers-cam-adjusters with the higher valve stem point creating the quicker wear or maybe even quicker bleed down of the adjusters. I've been running royal purple or Mobil one full synthetic 5/30 since I did the chains/tensioners the first time also...

I was able to replicate the sound for a second at cold idle earlier and it seemed to be coming from bank one. That's where the composite Vortech idler is. Still got my fingers crossed for that being the issue.

 

[96blak54]

Good luck man. Them 4v heads can be a pain.

 

[Wild Horses]

Good luck man. Them 4v heads can be a pain.

But boy are they worth the trouble! lol

 

[Wild Horses]

Good luck man. Them 4v heads can be a pain.

Sooo.... I drove the car 2 hours to the dyno early today... it made ALOT of power and then I ran out of fuel pump at 5500rpm, and yup...still rattling. Haha. I'm only at 11* total timing and 479@5500 then I lose the pump. This is with a 3.33 pulley. Idk... it's definitely strong and I've got quite a bit of room to keep going up to mid 500s he says. I'll be staying under 500 though. Even shifting at 5k this thing is insane. Lol

 

[96blak54]

Oh so you rattling is a lean condition?

 

[Wild Horses]

Oh so you rattling is a lean condition?

Oh nahh. The rattle is still the exact same. Only on light load or on the down rev between gears. The fuel pressure and duty cycle all the way up to 5500 is good and then the pressure drops like a rock and duty cycle pegs. Tuner says it's consistent with a tiny crack in the factory plastic flex line in the tank and I agree. I deleted the pprv because the 325 aeromotive has one built in. But I think when I did that the line probably split. I need to find a good way to replace that stuff.

 

[Wild Horses]

SO... I THINK I may have figured this out. Being the very first modular build I've done and doing all of the work myself, I overlooked one simple little thing...32 times. I put around 40 hours into porting my heads and a little more if I include rebuilding those things. Well I mentioned earlier in the post that I had lapped the valves... I did this with an electric drill on low speed as I have many times in the past. Well, being a mod motor where clearance specs are everything.... I FORGOT TO SET THE VALVES. Pushrod motors can compensate for this tiny raise in valve stem-to-rocker change and "setting the valves" is mostly only necessary when getting a full valve job and the seats are set deeper in.

My problem i think is I took too much valve seat out with the electric lapping and when the valve is all back together it then sits HIGHER. In turn pushing up on the follower and creating more preload on my lash adjusters AND camshafts. The lashers are working at the very bottom of their adjustment... bottoming out at times of low oil pressure. I noticed all of this with the valve covers off and seeing the light scoring around the cam lobes. That's where it became obvious that's the only thing that could do it.

The way to fix this is to go back and "set the valves", either by machining a tiny bit uff the bottom of every lash adjuster or by filing off a determined amount from the top of the valve stem.

This step completely slipped my mind and lapping valves should be standard practice if pulling heads due to the gobs of power/compression it restores. I think this info should be stickied with head rebuilding if it hasn't been already. I will post pictures of everything I'm talking about if anyone is interested.

 

[lwarrior1016]

Post up some pictures and what the specs should be. I think the grinding of the lash adjusters would be easier.

 

[Wild Horses]

Post up some pictures and what the specs should be. I think the grinding of the lash adjusters would be easier.

Will do... I haven't found exact specs for it yet but the process for measurement is with feeler gauges in the gap between the roller and cam lobe with lash adjuster completely compressed. Some people say cut down the valve stem because the lashers may blow out the bottom. But I can't see that happening when they have the oil and solid aluminum floor backing them. And we're only talking s couple thousandths MAYBE. If that.. I may have my machine shop deck each of them down the same amount so I know they're perfectly flat... I'm very surprised that more people don't have this issue.

 

[Wild Horses]

Post up some pictures and what the specs should be. I think the grinding of the lash adjusters would be easier.

Heres what she put down at the dyno tune a couple weeks ago btw. Have to go back after I fix the fuel pump line in the tank. Duty cycle kept pegging and pressure would drop at 6krpm. But this is just an SC Trim with a 3.33 pulley at around 7.5-8 psi and 11 degrees total timing!. Lol. Thinking about going up to the stock Vortech 3.60 pulley even to make it even more safe. The force is strong with this one. I was impressed with those numbers to say the least.

 

[Wild Horses]

Finally got my photobucket to work on my phone again. Here are the pics from the head rebuild and a lot of porting and recontouring. These things had my NA numbers in the upper half of THE 300s.

This is where most of the power is gained. All that extra aluminum at the valve seat transition came out first. You can also just see how pitted the exhaust side valve seats get. This is why heavier than usual lapping is necessary.

The very start. If these were mach1/03-04 heads that valve guide would almost be hanging into the port. That's their main difference. Luckily I had a set to look at that I was working on for a friend while I rebuilt my 01s.
Exhaust valve ports need ALOT of work. You can take a whole bunch out of those. But too much and they could drop from heat. I ground exhaust out to 70% total valve radius and the intake to 90% total.

I don't have many pics of the exhaust. I think by that time I had been grinding and reshaping for a full week and just wanted to get it done. But here's a pic of a roughed in exhaust port. They need most of the work. A lot is at the exit port but most is needed around the valve guide and in the seat transition.

I may post a new thread for all of the port work for anyone that wants to try it out themselves.

 

[Wild Horses]

Now... These are the wear marks around the cam lobes that started my thinking the valvetrain wasn't happy...

When I first pulled the motor last year... a full 60k miles on the cams and not a single bit of discoloration.

And here they are after the rebuild and weekend only driving for one summer.

Note how dark the bands around the lobes are. It's not every single one but damn close.

The secondary tensioner "flip" correction mod. You can also see the heat discoloration on the sides of the cam lobes in this pic.