Date: Mon, 9 Jan 2012 10:52:29 -0500
Reply-To: Gregg Carlen <gregg.carlen@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Gregg Carlen <gregg.carlen@GMAIL.COM>
Subject: Re: Smoke after head replacement
In-Reply-To: <BAY152-ds12D0771D41DAC8B4D5AE45A0980@phx.gbl>
Content-Type: text/plain; charset=ISO-8859-1
Yes, Dennis, I agree. Seems like a cylinder isn't firing. Going to re-check
obvious things as soon as I have a chance (plug wires, etc).
I don't have a leak-down tester, so will have to get one ASAP (what's the
advantage of a 2-guage vs single guage leak-down tester?). However, I
really suspect I've messed something up during installation of the
head because I think there is definately a coolant leak getting through to
the exhaust. I drained 1.5 gallons of coolant when I pulled the head and
I've returned a little more than 2 gallons now and it still wants more. I
also noticed if I put a piece of cardboard behind the exhaust and let the
mist collect into droplets, it's coolant.
The only things that come to mind that would cause a significant coolant
leak like this is one of the green o-rings came out of place during head
installation, or perhaps the head didn't seat correctly against the
cylinders. Or, one of the metal cylcinder gaskets (between the head and top
of the cylinders) slipped out of place during installation (and I crushed
it a wierd way during head installation).
If I had a valve that was open all the time or more than it is supposed to,
I wouldn't think that would have anything to do with allowing coolant
through the combusion chamber, right? Althought that might account for a
cylinder not firing/exhausting at the right time..
A few things I did that I second-guess in hind-sight:
Installed the green o-rings without any kind of lubricant
When I inspected the head after cleaning, I noticed the over-flow port
(where the small-diameter coolant hose goes between the overflow rail to
the adapter plate on the front end of the head) had one screw hole that was
very deep and had an opening in the bottom into what I think is the exhaust
chamber. I would if this leaked coolant or exhaust, I think it would be
allowing exhaust to escape to the outside of the engine since the bolt hole
is in the flange of the overflow adapter.
When I first put the head on by hand, I could only get it up to about 1" to
the engine case/gasket. From there, I tightened the head bolts in proper
sequence until tight. It seemed like the bottom of the head mated with the
engine case/gasket before the top of the head did (bottom of head made
contact with top of head still having about 1/4 gap). Perhaps I incorrectly
installed the head???
I just wanted to share these observations at this point. Next step is to
get a leak-down tester to learn more about what is truly occuring, but
until I verify I have all 4 cylinders firing, I don't want to drive or run
it more just yet.
Any guidance appreciated.
-Gregg
On Sun, Jan 8, 2012 at 9:07 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:
> For starters that engine is running really bad. Find which cylinder is not
> firing. You may have a push rod that is not seated properly in the lifter
> keeping a valve open. That will also keep some unburned fuel going into the
> exhaust.
>
> Shortly after a major engine repair a compression/leak down test should be
> performed again to confirm the success of the repairs. Check to make sure
> that coolant is not now getting into the cylinders. This will quickly
> damage the cylinders and pistons. Coolant in the oil will also damage the
> bearings.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Gregg Carlen
> Sent: Sunday, January 08, 2012 2:16 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Smoke after head replacement
>
> Hi folks,
>
> Similar to Todd Last's collapsed lifter that he shared a video about, I've
> got a similar situation on my 91 Westy. Oh yeah, I'm in Oakton, VA.
>
> I had the classic water gasket leaking coolant. I removed the passenger
> side
> head with engine in the van, cleaned it up, checked it for leaking using
> Scott's recommendation to check the valve guides using gas (I used parts
> cleaner instead of gas with no signs of leaking along the valve
> guides) and reinstalled. Did the fuel lines while I was on that side of the
> van as well. New gromets, gaskets, etc all the way around, nothing rubber
> reused. (I repalced the green o-rings on the cylinders, but no the black
> one's back inside the engine since I didn't remove the cylinder sleeves).
> So, all back together, she fires right up on the first try. Usual bleeding
> of the coolant, etc.
>
> Now, as I expected, there should be some smoke as oil/coolant that may have
> gottent to places it shouldn't have. There was. A lot of it. I thought at
> first it might be a collapsed lifter (one was squishy when I put the push
> rods back in). However, I don't have the knocking sound that Todd had in
> his
> video, just lots of smoke.
>
> I've run it about 10 minutes total and still no change. I'm wondering if
> I've managed to mess something up and actually have coolant getting into
> the
> combusion process.
>
> Any advice as to what to check first? Or, just need to run it more? I did
> NOT adjust the valves, just replaced the assemble as I had taken it off.
> Perhaps I need to go through the valve adjustment process? (Although I
> don't
> here anything abnormal from that area).
>
> A short video is here:
>
> https://picasaweb.google.com/lh/sredir?uname=113741720077010029753&target=AL
> BUM&id=5695338093044400273&authkey=Gv1sRgCIeJqISt-qiL5gE&feat=email
>
>
> Gregg
> Blueberry - 91 Westy (2.1L stock)
> Oakton, VA
>
>
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