Date: Sat, 14 Jan 2012 20:25:40 -0800
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Smoke after head replacement
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
a few comments..
the black o-rings at the bottom of the barrels can be replaced without
removing the barrels.
Put the piston at tdc ..
pull the barrel up 'enough' but not so far that the rings pop out.
The black o-ring will stretch nicely to fit over the barrel..
the groove is a very nice design ..the o-ring always just goes where it
belongs in my experience.
I could not say that worn or leaking intake valves are common on fuel
injected engines.
In waterboxers...
of the last say ..whatever ....30 of them I've had heads off..
I usually find slightly leaking exhaust valves in 2.1 wbxrs ..
I may have seen one really bad intake valve in all those engines..
and a couple leaking slightly, if that.
fwiw, to the list in general.
I can't say that worn guides can cause leakage..
in 1.6 turbo diesel engines pushing a vanagon ...
the exhaust valve guides go south in about 30K miles...
if you lift the valve up off the seat ..,
the valve has almost 1/8th inch side play ..
in other words, 'a mile' ........but the valves still seem to seal pretty
well actually.
excessive oil in the intake guides for whatever reason ..wear or missing
valve seal, if it's supposed to have one..
can show up as oil consumption. and smoke on a warm restart
...Early gas Rabbits where famous for that..
VW even started putting a 'check the engine oil' sticker on the fuel filler
door just due to that.
what fun,
Scott
www.turbovans.com
I'll try, mostly, to behave.
----- Original Message -----
From: "Dennis Haynes" <d23haynes57@HOTMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, January 14, 2012 2:51 PM
Subject: Re: Smoke after head replacement
> Let's be sure we are referring to the cylinders correctly as #1 and #3 are
> not on the same head. #1 and #2 are on the right side. #3 and #4 are on
> the
> left. #1 and #3 are front opposite.
>
> For the intake valve #3 leaking is most likely due to bad valve or worn
> guide. Machine shop work here. Leaking intakes are extremely common on
> fuel
> injected engines.
>
> For the coolant getting into the oil only path on the Waterboxer is
> through
> a loose or broken head stud under the rockers or the base of the
> cylinders.
> Did you use a torque wrench?
>
> To me you need to pull both heads, find out what was done wrong and also
> pull the cylinders to replace the O-rings underneath. You need to get that
> coolant oil mix out of the crankcase and creatively get some fresh oil in
> there. The coolant will quickly destroy the bearings.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Gregg Carlen
> Sent: Saturday, January 14, 2012 4:58 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Smoke after head replacement
>
> Okay, I got a leakdown tester and ran a leak down test.
>
> Even before I ran the test, I knew there were problems (beyond the smoke
> in
> the exhaust). Besides the rough running (as seen in the video clip
> earlier),
> the oil was peanut butter. So, coolant is getting in the oil. Note: the
> coolant in the reservoir was still translucent green, so I suspect that
> oil
> isn't getting into the coolant. But this is just a loose assumption.
>
> Leak down on cylinder #3 had a 70% leak. Air was leaking from the air
> intake. Couldn't feel or hear anything from the exhaust (although it could
> be week enough that I didn't hear/feel anything)
>
> Leakdown on cylinder #1 had a 90% leak. Air was coming out from the air
> intake and the coolant bottle was bubbling. Again, didn't observe anything
> from the exhaust.
>
> So, my initial assessment is I have two problems. One, regarding the air
> leak into the coolant, the head sealing ring (between the head and the top
> of the cylinder) on the #1 cylinder is not seated/sealing properly. Is
> this
> also the reason for coolant getting into the oil?
>
> Second, the air leak coming out of the intake manifold tells me I've got
> intake valves open when they should be closed.
>
> So, if my conclusions are right, I basically get to pull the head again,
> inspect the sealing ring and mating surfaces thoroughly, then reinstall
> and
> do a valve adjustment).
>
> Sound about right?
>
> As a wise old Sargeant used to tell me in the Army, you'll always have
> time
> to do the job right the second time if you rush through it the first time.
>
> Gregg
> 90 Westy (Blueberry)
>
>
> On Jan 9, 2012, at 6:16 PM, Dennis Haynes <d23haynes57@hotmail.com> wrote:
>
>> For a novice the single gauge Milton is the easiest to use. The
>> measurement is not that critical. The ultimate test is to secure the
>> engine from turning and then using full shop air charge the cylinder
>> and listen to where the air escapes. Do this with the coolant pressure
>> cap
> removed and tank topped off.
>> Any movement of the coolant level is an immediate problem.
>>
>> The metal gaskets at the top of the cylinders are where the real
>> sealing occurs. The green rings are just there to keep the liquid away
>> from that gasket junction. It won't hold back anything once that metal
> gasket fails.
>> When re-using the heads and cylinders one has to be real careful the
>> surfaces are clean. Any carbon will make the seal fail. I pull the
>> cylinders and use lapping compound and turn them into the heads to get
>> both surfaces polished up ready to seal. Proper torque of the head
>> studs is extremely critical here. The nuts really should be replaced
>> or at least chase the threads with a tap. The threads need a lubricant
>> and only the face gets the yellow sealant. If a stud twists and
>> springs back during final torque the threads were not prepped right or
>> the stud is defective. The outer rubber only holds the coolant in and
>> will have no effect on engine operation except the loss of coolant.
>>
>> Dennis
>>
>> -----Original Message-----
>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
>> Behalf Of Gregg Carlen
>> Sent: Monday, January 09, 2012 10:52 AM
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Re: Smoke after head replacement
>>
>> 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&ta
>>> r
>>> get=AL
>>> BUM&id=5695338093044400273&authkey=Gv1sRgCIeJqISt-qiL5gE&feat=email
>>>
>>>
>>> Gregg
>>> Blueberry - 91 Westy (2.1L stock)
>>> Oakton, VA
>>>
>>>
>>
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