Date: Fri, 5 May 2017 11:16:01 -0700
Reply-To: Stuart MacMillan <stuartmacm@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stuart MacMillan <stuartmacm@GMAIL.COM>
Subject: Re: 2.1 wbx Compression Test
In-Reply-To: <CAB2RwfjZfFUd-GumVamKg2YjeT+6KLz9Fe3+pWTK_Uqi_v_S6A@mail.gmail.com>
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If I were you I'd just keep driving and put your energy into the conversion. Better way to spend your time. There is no easy/cheap fix for your engine, so best to focus on the next engine. You don't care about blowing it up anyway!
Stuart
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Neil N
Sent: Friday, May 05, 2017 9:11 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 2.1 wbx Compression Test
Thanks Dennis.
The Gowesty vacuum type throttle switch was disconnected because the wires were slightly in the way of the AFM-filter housing. In hindsight, a hasty thing to do. The ignition coil lead was disconnected from coil, throttle body valve held open during test.
It's occurred to me that the lifters may be at play here. The engine sat for some time unused. I ran it before the compression test, heard zero lifter noise so I assumed the lifters were fully pumped up. If I recall, it took several cycles of the starter motor to bring each cylinder up to its' maximum pressure.
Looking at my notes, when purchased, this is what the mechanics test showed for engine compression:
130 120
140 140
I had wondered about doing a leak down test. An air compressor purchase may be in my future!
Neil.
On 5/5/17, Dennis Haynes <d23haynes57@hotmail.com> wrote:
> A compression test is not complete without also doing a leak down test.
> Also, when doing a compression test you want to disable the fuel pump
> and ignition coil or at least center the center coil wire to ground.
> Throttle should be held open. What did you expect to accomplish by
> disconnecting the throttle switch?
>
> As an extension of a leak down test when you get a cylinder with a low
> reading you can bypass the gauge set and put full available air
> pressure in the cylinder. Be sure the crankshaft is secured for this.
> For the ultimate extension of this test you can remove the rocker arms
> so you can test the piston-rings at both the top and bottom of the
> cylinder. During these tests remove the pressure cap and have the
> coolant topped off all the way to the brim. Major internal leaks will
> quickly be obvious with the coolant pushing up or bubbling. Very small
> leaks or leaks that open under heat or pressure may still hide.
>
> I discovered this anomaly on Fun Bus around 200K. I have also seen it
> on other engines. Since Fun Bus does not have any coolant issues and
> the leak down test is good I am still driving it and it is now over
> 313K
>
> Dennis
>
>
--
Neil n
Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
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