Date: Sat, 9 Oct 2004 23:50:23 -0400
Reply-To: ROBERT DONALDS <donalds1@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: ROBERT DONALDS <donalds1@VERIZON.NET>
Subject: Re: '86 Westy Oil light flickers briefly...other basic ?'s
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I distortion of the big end of the con rod greater in the 2.1 engine than
the 1.9 but not as you might think. The big end of the rod gets smaller in
line with the main beam or opposite the parting line. It also has an
increase in cap shift at the parting line compared to the 1.9 rod. I think
the bolt is the reason the 2.1 rods distorts as I have described is because
the bolt is a flexible joint. The stretch to yield bolt is stretched when
the 1/4 turn past 22 pounds torque is done. and offers a higher value of
clamping pressure in this state of yield. The 1.8 Golf, Jetta engines use a
stretch to yield bolt to hold the head to the block this is where this type
of hardware shines. The head has the same pressure on the head gasket cold
or hot the thermal expantion does not effect the pressure.
SO the part is distorting and the bolt is stretching but the bolt does not
get loose over time the part distorts over time
This is known as the hoaky poaky effect here at the engine exchange
for more than you ever want to know about stretch to yield hardware
http://www.babcox.com/editorial/ar/ar20134.htm
going faster miles an hour with the radio on
I remain
Bob Donalds
Botson Engine
all rights reserved
----- Original Message -----
From: "Jim Felder" <felder@KNOLOGY.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, October 09, 2004 10:23 PM
Subject: Re: '86 Westy Oil light flickers briefly...other basic ?'s
>I agree the he da man. I bookmark a lot of his stuff for the occasion
> in the future when I will have to rebuild my engine, certainly he is a
> greater authority than I am. I'm not suggesting otherwise. I haven't
> gone to look up his opinions on this issue specifically so I don't know
> specifically about what you're quoting, but my machinist's training
> tells me that ovalizing is ovalizing through distortion, and bolt
> stretching--if it is indeed happening--is a whole other thing. Either
> the part is deforming or the bolts are stretching. If the part is
> ovalized or distorted out of shape, then different bolts won't help. It
> needs to be thrown away. If the part isn't oval but the bolts are
> stretched, then it isn't "ovalized," it's simply loose.
>
>
> Jim
>
> On Oct 9, 2004, at 8:45 PM, John Rodgers wrote:
>
>> I defer to the expertise of Bob Donalds of Boston Engines on this one.
>> He has written much on the subject of WBX 2.1L cases, bearings, rods,
>> rod bolts, and cranks, all based on hands on experience of rebuilding
>> many, many WBX engines. So far as I am concerned "He da man!"
>>
>> Regards,
>>
>> John R
>>
>> Jim Felder wrote:
>>
>>> My take on this is purely anecdotal, but I think that people who have
>>> ovalized big-ends have been driving too fast for too long.
>>>
>>> Porsche 911s have stretch bolts on the big-ends, too, but they don't
>>> "keep stretching." I got a lot more than 150K on a 911 and have a lot
>>> more than that on my 2.1 now, and the oil pressure is good. I never
>>> revved the 911 over 7.2K and don't ever rev the vanagon over 4K, the
>>> intended redline for both. Anyway, if the bolts were to stretch you'd
>>> have a double-radius circle with gaps where the separation was
>>> occurring (where the cap fits) and it would be very easy to spot this
>>> when the engine came apart. You would actually be able to put a feeler
>>> gauge in the gap in between the cap and the rod body. Plus, I think
>>> you'd definitely hear the racket and the oil pressure would drop to
>>> zero in a big hurry as soon as a crack opened up.
>>>
>>> If the big-ends are becoming oval, I bet it's from either
>>> under-designing the rod or putting more centrifugal force on it than
>>> it
>>> was designed to have (running it over 70 mph, say). I doubt that the
>>> bolts are stretching, though. If an inside micrometer or plastigage is
>>> used to determine that a big-end is out of round, it's going to be out
>>> of round whether the bolts have stretched or not, and will be out of
>>> round no matter what kind of bolts are put back into it. It would be
>>> the rods in this case, and not the bolts, that need replacing.
>>>
>>> Jim
>>>
>>>
>>> On Oct 9, 2004, at 2:15 PM, John Rodgers wrote:
>>>
>>>> Larry,
>>>>
>>>> One more nightmare to know about........!
>>>>
>>>> The stock 2.1L engines use a "Stretch to spec" bolt for the rod
>>>> endcaps
>>>> that clamp the rod to the crankshaft. During the life of the engine
>>>> these bolts continue to stretch and somewhere in the neighborhood of
>>>> 130-150 thousand miles, the rod bolts will have stretched enough to
>>>> allow the rod ends to become oval. When that happens, oil pressure is
>>>> lost, and without lubrication galling of the rod bearing on the crank
>>>> throw occurs, and then the rod locks to the crank, breaking the bolts
>>>> and the rod, and throwing it throuugh the engine block.
>>>> Congratulations,
>>>> your engine has been reduced to a pile of metal ruble in a few
>>>> moments.
>>>>
>>>> The more knowledgeable mechanics fix this problem when the engines
>>>> are
>>>> rebuilt, by installing 1.9L rod bolts, which are no-stretch types.
>>>>
>>>> For more on this and other engine things, go to
>>>> http:\\www.bostonengines.com. Bob Donalds there has a wealth of stuff
>>>> about the subject.
>>>>
>>>> Regards,
>>>>
>>>> Johjn Rodgers
>>>> 88 GL Driver
>>>> ]
>>>> Larry Occhipinti, DVM wrote:
>>>>
>>>>> Dear Vanagon Listmates,
>>>>>
>>>>> I'm new to this list, and a first time Westy owner ('86) and glad to
>>>>> be
>>>>> onboard....from the few posts I've gotten today this should be a
>>>>> great
>>>>> learning experience.
>>>>>
>>>>> I'm not a mechanic by any means, so I am hoping someone on this list
>>>>> can
>>>>> recommend a good westy mechanic in the Newport, Oregon area who can
>>>>> tend to
>>>>> my '86 Westfalia...
>>>>>
>>>>> I just aquired my first Westy on Sunday....luckily for me it has
>>>>> been
>>>>> gone
>>>>> through very extensively during the last 12 months and 10,000 miles-
>>>>> completely
>>>>> rebuilt engine/replaced heads, new exhaust system, brakes, cooling
>>>>> system,
>>>>> clutch, etc...it is a good runner for sure, but occasionally the oil
>>>>> warning
>>>>> light flickers on briefly.
>>>>>
>>>>> It was a quart low on oil when I got home with her, and I topped her
>>>>> off
>>>>> before heading out yesterday morning, and while it is not doing it
>>>>> as
>>>>> often
>>>>> now, it still occasionally flickers, especially when rpms are
>>>>> low...I
>>>>> figure no big deal since it runs so great, but thought I'd ask if
>>>>> this is
>>>>> something that should be addressed.
>>>>>
>>>>> Another basic question is should I follow the factory rec for oil
>>>>> changes
>>>>> every 7,500 miles, or do my usual every 3,000 mile change?
>>>>>
>>>>> Is it vital to only use the factory german oil filters, or are the
>>>>> ones
>>>>> installed at the neighborhood oil change places adequate?
>>>>>
>>>>> I'm using Castro 20/50 wt oil....hope that is the best for these.
>>>>>
>>>>> It is not leaking a drop that I can see on the driveway.
>>>>>
>>>>> Do have the blue coolant....should I add it full strength for top
>>>>> offs , or
>>>>> dilute 50 : 50 with distilled water?
>>>>>
>>>>> Sorry for all the questions on my first post....thanks again, and if
>>>>> there
>>>>> is a good westy mechanic in my area please let me know where he is!!
>>>>>
>>>>> Looking forward to gaining good basic pointers from you all and
>>>>> sincere
>>>>> gratitude for your sharing of pertinent vanagon info...
>>>>>
>>>>>
>>>>> Larry Occhipinti
>>>>>
>>>>> Newport, Oregon
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>
>
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