Rattling and imbalance on the engine

[Niko7]

Hey Guys,

First off all, i read several Threads and Q&A´s before.

Just wondering.
My 99 GTS Viper (60.000km) with big cam, as soon as it warms up, it has a rattle sound. Sounds like worn lifter or rocker arms, definitely Valvetrain. Therefore i did put 10w60 and additive for lifters, which fixed the problem temporarely. Now it´s back, so i guess rocker arms are bad/worn.
Which one to buy? What do you guys recommend

When engine is cold, i have no rattle at all! But changes after 2 miles or so.

You know, it starts at around 1300rpm noticeable, at around 3200-3500 it is really bad and loud rattling, exactly like a Industrial Sew Machine and over 3700 you can not hear it any more (probably due to the exhaust is overwhelming it or it changes pitch / gets enough torque to not ticker any more )

But, additionally i have now noticed an imbalance with vibration and i can feel the engine shaking not to soft on the shift stick over 4500rpm. Feels not great to be honest. Feels like i should not give it more then 4500rpm....But power is there like it shoud.
Any suggestions what could cause the Vibration? You can feel it in the Whole car but in the stick it´s very present. Bend Pushrod? Broken Balancer? Broken Gearbox Shaft? Flywheel broken? What issues are comon?

Engine/Gearbox mounts seems like to be Original, but i think that Vibration/Imbalance is way to much for engine mounts or to say it´s normal.

Best,
Niko

 

[TEALLIFE]

Are you sure it's not an exhaust leak or cracked header? Probably not that if its a rattle (unless its just loose). A very bad engine mount you'll visibly see if you rev it with the hood open.

oil and additives definitely arent the way to fix it....running too thick an oil can cause other problems.

using a stethoscope or similar homemade device, try and track it down to the head/location to be sure. also check the temps on each cylinder to make sure theyre all firing evenly.

 

[GTS Dean]

First thing to do RIGHT NOW is to confirm that your crank damper bolt is not loose. It isn't easy to get a wrench on, but imperative that you do! Are you having any steering issues too?

You'll need a 1.25" or 32mm deep socket and a breakover bar. Or a short one with the right extension.

 

[Goggles Pizano]

Why haven't you pull the valve covers it you think rockers or lifters?

Do what Dean's said or you will be asking Mike for a new crank.

 

[Dan Cragin]

Lots of questions. I have lots of experience with all this over the past 30 years building Viper engines, feel free to call me if needed.

Dan 310-597-6295

 

[99RT10GTS]

You need to start by pulling the covers, but by now your engine is probably toast. I sell new short blocks when you're ready

 

[Niko7]

First thing to do RIGHT NOW is to confirm that your crank damper bolt is not loose. It isn't easy to get a wrench on, but imperative that you do! Are you having any steering issues too?

You'll need a 1.25" or 32mm deep socket and a breakover bar. Or a short one with the right extension.

How to exactly find the Screw? Do i have to pull the Crank pulley?

Steering issues? Not that i know.

Thanks

 

[GTS Dean]

You can access the crank damper bolt without removing g the pulley, but it's awkward. (6) 1/2" hex bolts and the pulley is off.

 

[Niko7]

Good News:
I can access the Balancer/Crank Nut Screw with ease while the Pulley is on. Has a Cut out.
But nothing wrong there. Everything seems to be tight and in place. Only thing i noticed, the balancer is quite rusty.

Also checked the axial and horizontal play on all belt movings and stuff. Looks fine. Friend of mine has a Garage Shop. He will Pull the Pan to check lower Engine.

I found one Spark Plug that looks like it leakes Exhaust Gases....Hope i can get it out the Head without pulling. Looks horrible though...