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