If it's changing with RPM's...it's going to be something
mechanical...probably in the valvetrain. What length pushrods are you using
and what cam/valvespring combo are you using?
- Bernd
-----Original Message-----
From: WiLieR[SS] [mailto:waffle787@gmail.com]
Sent: Friday, May 04, 2007 10:52 PM
To: dakota-truck@dakota-truck.net
Subject: Re: DML: RE: Timing 3.9 v-6
I have used an actual mechanics stethoscope and hear the noise throughout
the whole head and a little in the intake and exhaust manifolds and the
block. I can't get to the timing cover itself but don't hear the noise in
the front accesories (alt, ps pump, etc...) And have ruled out the evap
solenoid mounted to the rear of the left fuel rail. There is no CEL and no
stored codes. I forgot to mention that I have had a cold stall issue
lately. When cold it acts like a very cold natured beast and will throw
bogging fits if I don't go easy on her for a few miles. It has backfired
through the left exhaust manifold once during this as well. The timing
chain is an oe style cloyes replacement with about 70k on it and the
tensioner.
WiLieR
- Original message -
It'll jump around - again (and I forgot to put TPS in the mix in the
previous post)...throttle position, coolant temp, battery temp, O2
readings, MAP Baro reading, and Intake Air Temp all have a lot to do with
the timing (and fuel obviously). Have you tried listening to the tapping
noise with something like a broom handle up to your ear and across the
valve covers? Basically like a crude stethoscope. - Bernd
On 5/4/07, Bernd D. Ratsch <bernd@dodgetrucks.org> wrote:
>
> It'll jump around - again (and I forgot to put TPS in the mix in the
> previous post)...throttle position, coolant temp, battery temp, O2
> readings, MAP Baro reading, and Intake Air Temp all have a lot to do
> with the timing (and fuel obviously).
>
> Have you tried listening to the tapping noise with something like a
> broom handle up to your ear and across the valve covers? Basically
> like a crude stethoscope.
>
> - Bernd
>
> -----Original Message-----
> From: WiLieR[SS] [mailto:waffle787@gmail.com]
> Sent: Friday, May 04, 2007 9:33 PM
> To: dakota-truck@dakota-truck.net
> Subject: Re: DML: RE: Timing 3.9 v-6
>
>
> I have reinstalled the stock rockers and it still taps. I never did
> get a true reading of the timing with my light, but somthing tells me
> that the timing mark shouldn,t disappear under the water pump and only
> reappear when I open the tb up. Even then it doesn't come but about
> 4-6 degrees before tdc.
>
> WiLieR
>
>
> On 5/4/07, Bernd D. Ratsch <bernd@dodgetrucks.org> wrote:
> >
> > It will vary depending on a variety of sensor inputs (BARO, CTS,
> > BTS, IAT, O2), but normally it'll be somewhere in between 4-12.
> >
> > Are you sure it's not the roller rockers you're hearing?
> >
> > - Bernd
> >
> > -----Original Message-----
> > From: WiLieR[SS] [mailto:waffle787@gmail.com]
> > Sent: Friday, May 04, 2007 8:40 PM
> > To: dakota-truck@dakota-truck.net
> > Subject: DML: Timing 3.9 v-6
> >
> >
> > I know the timing can't be adjusted by rotating the distributor and
> > such, but what is the base timing of a 96 3.9 v-6 when at operating
> > temp and at idle? I am having so tapping issues andf have exhausted
> > all the upper end engine possibilities. New parts are as follows:
> > lifters, head gaskets, 1.7 harland roller rockers, valve springs,
> > pushrods, intake gaskets (including plenum pan), heads completely
> > checked over with some blending and polishing work done.
> >
> > The tapping is not a ping or knock as I have tried everything from
> > 87 octane to 93 octane with octane boost in it. I can hear the
> > noise in both cylinder heads and the exhaust manifolds with a
> > noticeable noise in the exhaust tone (no cat and flowmaster 40
> > series). It is a rhytmic tapping that cahnges with rpm. The
> > tapping goes away when the engine is under load but reappears
> > immediately when not under load (cruising, idling or deceleration).
> > It is loud enough to be heard as an echo off close buildings, bridge
> > sides, fences, etc... I have tried 10w-30 and 20w-50 oils with no
> > difference at all. Oil pressure is
> strong, even when the engine is warm.
> >
> > It is driving me nuts! It literally sounds like a garden gnome high
> > on caffiene and sugar pills in my engine with a ball pein hammer!
> >
> > Any ideas? Much more of this will cause me to start randomly
> > smashing those little gnomes when I see them.
> >
> > WiLieR
> >
> >
> >
> >
>
>
>
>
This archive was generated by hypermail 2b29 : Fri Jun 01 2007 - 09:06:10 EDT