Date: Thu, 24 Oct 2013 14:02:40 -0700
Reply-To: Scott Daniel <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel <scottdaniel@TURBOVANS.COM>
Organization: Cosmic Reminders
Subject: Re: off with her heads
In-Reply-To: <CAFnDXk2zvYqv7=-uHFGNDHEozNxT_K+206T7cOZh6sBDe-LXJg@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I have always been very speeling challenged !
On 10/24/2013 1:43 PM, Jim Felder wrote:
> No, "barring." Baring might get him arrested, especially if he were driving
> around doing it in a Vanagon.
>
> Jim
>
>
> On Thu, Oct 24, 2013 at 3:31 PM, Scott Daniel <scottdaniel@turbovans.com>wrote:
>
>> HI Angus ..
>> on the 'bar thing'..yeah, Angus turned me onto what you meant.
>> The word you wanted was 'baring' .
>>
>> On the rings ..I find that compression rings go in fairly easily ..
>> it's the oil rings that are a tight squeeze sometimes.
>>
>> One way to gauge piston ring and barrel wear is to remove an old ring
>> from that piston,
>> put it in the barrel and measure the end gap of the ring, then compare
>> that to spec.
>>
>> You'll likely find pretty 'good' wear.
>>
>> I forget how many miles on your engine ..
>> and it's always .."Do I just fix what's really broken or worn badly ? ..
>> or do I go further ?
>> And ....once you do 'this' ..then might as well do 'that' too ..
>> and it just keeps growing that way.
>>
>> Need to draw the line somewhere ..
>> it's tempting to do new rings and rod bearings ...
>> but then you might as well do X too ...........etc. etc. etc.
>>
>> yes, the right forward cylinder is # 1 .
>> VW has used that numbering pattern in their oppossed fours since about
>> 1950, if not before that even.
>>
>> here's a neat trick ..
>> when you are adjusting your valves, turn the engine backwards to get to
>> each cylinder on compression in turn ...
>> that it's 1, 2, 3 , 4 . Confirm which cylinder you are on by dist
>> rotor position .
>>
>> If anyone is interested in rebuildable 1.9 core waterboxer engines ....I
>> have about 6 and don't want much for an assembled short block.
>> You can make a 1.9 DH code engine into 2.1 by putting a 2.1 crankshaft
>> in it.
>>
>> Scott
>>
>>
>>
>>
>>
>> On 10/24/2013 8:08 AM, Tom Carchrae wrote:
>>
>>> @Scott:
>>>
>>> Thanks for confirming about the valves. I'm not entirely sure which ring
>>> it is, I'll go and have a closer look today. Btw, I didn't adjust
>>> anything
>>> with a bar - bar was meant as a synonym for 'except'. I am pretty sure it
>>> is cylinder #1 (it is the closest to the passenger seat).
>>>
>>>
>>> @Dennis;
>>>
>>>
>>> On Wed, Oct 23, 2013 at 10:50 PM, Dennis Haynes <d23haynes57@hotmail.com>
>>> **wrote:
>>>
>>> Please take this as training.
>>> I do take it that way - mistakes are the best teacher, so they say?....
>>> but
>>> still enjoying learning and working on it.
>>>
>>> I also very much appreciative of all the time and insight you, and others,
>>> on the list are so generous with.
>>>
>>>
>>>
>>> At the point that compression test was taken
>>>> that engine should have been taken out of service and further evaluated.
>>>> All
>>>> the cylinders are down and the one with 60 psi indicates a failure. If
>>>> you
>>>> had an emissions test program it should have failed. The catalyst is most
>>>> likely shot. More concerning is while that cylinder was down the
>>>> remaining
>>>> three had to work harder to compensate.
>>>>
>>> That is the strange part - it passed the emissions test fine, not even
>>> close to failing. The mechanic who did the compression test also thought
>>> it would be a problem. So, I don't understand how that works, except
>>> perhaps that Vancouver's AirCare is a farce - one that they are ceasing to
>>> operate next year.
>>>
>>>
>>>
>>> This often translate to increased
>>>> wear on the rod bearings. The oil contamination from unburned fuel
>>>> doesn't
>>>> help things. Before taking the engine a part a leak down test would help
>>>> to
>>>> diagnose if you had a valve or a ring problem.
>>>>
>>>> This is was my most expensive lesson. I took it to a mechanic, and
>>> asked
>>> him to do a leak down test, and to look at the compression problem. He
>>> reported back that he had got the compression back up by adding racing
>>> lash
>>> caps. I recall asking him about the leak down, and got back 'fine', and
>>> 'it holds pressure', and so on. It is clear from what you're saying that
>>> I
>>> should replace the valve adjusting screws, not just pad them with lash
>>> caps.
>>>
>>> Shortly after that, he changed the expansion cap, and I started to get a
>>> really expensive series of coolant explosions. Then I drove the van
>>> across
>>> western canada, with a few incidents, although after I changed the
>>> pressure
>>> cap to another one I didn't have any more explosions - just coolant backup
>>> behind the plate, and it was fine for an entire leg of the journey home.
>>> Each experience made me want to fix it myself more - the last incident
>>> was
>>> taken care of while we stopped for lunch (the first involved a tow truck,
>>> waiting around for a day, and a crappy patch on a hose).
>>>
>>> Anyway, all that is now water under the... no, coolant under the van? har
>>> har. sorry, sorry... groan-worthy.
>>>
>>>
>>>
>>> Now that the heads are off there are some easy checks you can make. Put
>>>> the
>>>> spark plugs in and set the heads with the combustion chambers facing up.
>>>> Fill the chambers with some light liquid like WD-40 or even carb cleaner.
>>>> You will find leaking valves real fast.
>>>>
>>> Thanks. I'll give that a shot before I dig further into the valves. I
>>> saw
>>> a video of someone doing that, but it was on a different type of engine.
>>>
>>>
>>>
>>> The exhausts should not be ground.
>>>> If the seat are cut or the valves ground the stems should be shortened
>>>> and
>>>> the springs shimmed to compensate. This is to maintain spring pressure
>>>> and
>>>> rocker geometry. Adjusting screws should always be replaced. If the valve
>>>> guides are worn it is likely time for new heads. These are a heat the
>>>> head
>>>> to 400 and cool the guides in liquid nitrogen fit. Otherwise they tend to
>>>> go
>>>> in off center and the seats will need a lot of cutting to compensate.
>>>>
>>> ...and I though the spring tool was going to be fiddly.
>>>
>>> They are newish AMC heads, no pitting (aside from some crowbar scratches).
>>> I think they were done 5-10 years ago according to the receipts log, but
>>> I'm not sure both sides were done at the same time. I've read the bit
>>> about the AMC valves being terrible. I'll do some more reading up on how
>>> to check those (aside from WD-40 test)
>>>
>>>
>>> Back
>>>
>>>> when VW rebuilt these heads they almost always ended up drilled out and
>>>> fitted with oversized guides. A lot of labor. Make sure the intakes get
>>>> the
>>>> oil seals. ETKA does not show them but they should be there. I have a
>>>> bunch
>>>> in stock. They will keep oil from getting sucked down the intake guides.
>>>>
>>>> and that would help prevent the valves and cylinder getting filthier?
>>>
>>>
>>> You need to remove that carbon ridge at the top of the cylinder. The new
>>> top
>>>
>>>> ring can get broken hitting it. If honing the cylinders remove as little
>>>> material as possible. A few more thousandths and you will have an engine
>>>> with piston slap noises. With the cylinders out at least measure the rods
>>>> for play and bearing wear. The rods and bearings can be replaced without
>>>> splitting the case, (this sucks but do-able).
>>>>
>>>> I've been reluctant to pull any more cylinders out until I try getting
>>> one
>>> back on.
>>>
>>>
>>> Good luck,
>>>
>>>> Dennis
>>>>
>>> Thanks Dennis - very much appreciated.
>>>
>>> Tom
>>>
>>>
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