Re: Surging 4kcsq

["Doyt W. Echelberger" <Doyt@NWOhio.com>]

Thanks for the reply and encouragement, John.   I haven't been reading the
'Stabilitant' thread because (duh) I thought it was about fuel additives
for winter lay-overs, to keep the fuel from varnishing. I see now that it
is designed to improve healthy electrical contacts. I'll try to get some.

Will certainly take off and re-ground the copper mesh strips you refer to.
Makes sense to me.Also checking plug wires, injector seals, and ISV function.

In observing the idling engine, I note that the (new this week) molded
rubber hose between the mid-point of the IM and the ISV runs totally
collapsed along about 2 inches of its length just past where it does a 90*
bend at the mid-point of the IM. When I speed up the RPMs this collapse
opens up. The old hose was soft and cracked in several places and I put on
a new one, but I can see where that collapsed section might be fluttering
open and shut and escalating the changes between the components that tie
into the EM, creating an oscillating pressure event.

Lots of components tie into it.

One of the vacuum connections from it runs over to the air filter box on
the atmospheric side of the mixture control unit. Another goes off to the
activated charcoal tank. And another goes to the switch for the diff lock,
and another branches to a 'Y' at the ISV. The mixture control function and
the ISV are critically associated with how the engine runs, and so (to me)
are suspects in the surging problem.

Looks like a nasty place for a collapsed, pulsing vacuum hose. I am tempted
to insert a two inch length of heavier-wall hose in the lumen, to stiffen
it up. And of course work on the electrical grounds. My Bentley shows LOTS
of ground points.Any more ideas are very welcome.

I'll give you some more background: This is the replacement engine for the
car that got caught in a flood a few months ago and hydrolocked while
running.The basic block and intake manifold came out of a VW Quantum,
salvaged at 67k miles. I had the rear main seal and cam seal replaced,
along with the water pump, idler pulley and timing belt. All the engine
grounds were reattached at the engine swap.

The flood destroyed the catalytic converter, so I am running without one.
And I suspect some bizarre damage to the air intake channels, since they
sucked in about 3 quarts of high velocity water which came slamming into
and through the air filter on its way to all 5 cylinders. With that kind of
submersion, I also suspect water damage to all the little valves and seals
of the entire vacuum system branching off the IM. So that is where I am
focusing, using the Bentley diagrams of the US model pollution control system.

It seems a reasonable possibility that the surging problem has its origin
in the system that sustained most of the stress of the event that destroyed
the original engine. End of background babbling. Keep talking to me,
people. It has helped greatly already.


Doyt
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

At 11:41 AM 6/13/98 EDT, you wrote:
>Doyt, You don`t often see leaking c/s valves, so it`s kind of a reach.
>I`d look, really look at the system grounds. There are grounds all over
>the place, and the ECU needs to have a really good ground to the engine,
>Ck also the ground from eng to coil bracket bolt. I`ve seen lots of
>problems at the ground point on the inlet manifold from the ECU.
>Recently on the digest there has been some discussion of "Stabilant".
>Get some, and some high quality contact cleaner, and go for it. I`d also
>take a good look at the temp sensor and it`s wiring. I wish you good
>luck, but diligence and attention to detail are going to fix this. I,
>personally, hate problems like these, but they do happen, and they CAN
>be solved. John.
>
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