Date: Mon, 8 Jan 2001 21:58:19 -0800
Reply-To: Mark Dorm <mark_hb@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Mark Dorm <mark_hb@HOTMAIL.COM>
Subject: Re: "windage tray" and other I4 conversion comments
Content-Type: text/plain; format=flowed
Astrobiology? Does Agent Muldry now about this?
So how do we insure that our exhaust systems are mounted unpoorly?
>From: Frank Grunthaner <FrankGRUN@AOL.COM>
>Reply-To: FrankGRUN@AOL.COM
>To: vanagon@GERRY.VANAGON.COM
>Subject: Re: "windage tray" and other I4 conversion comments
>Date: Mon, 8 Jan 2001 02:32:51 EST
>
>This is the end of an extensive travel period and the onset of the
>submission
>deadline for a new round of NASA space science and Astrobiology research
>proposals, so I have been in a more-passive-than-usual lurking mode. A few
>quick comments about some I4 conversion questions:
>
>First, on the issue of the Windage tray, the unit you want is the VW stock
>item for many (not all) of the 2.0 l ABA engines. The part number is
>037-115-220 B and is available from VW dealers, and most VW performance
>aftermarket suppliers (Tectonics, etc.). The unit is quality with a capital
>D
>(Deutsch). The unit is a stamped tray and feels as if it is made of copper.
>A
>previous poster said the tray came with a rubber gasket. Not quite true.
>The
>integral rubber gasket is molded as part of the tray. In the bolt hole
>areas,
>metal sleeves are molded into the gasket to control gasket compression when
>torqueing the pan bolts. The tray/gasket is designed for repeated use,
>requires no goop for sealing and fits perfectly on all ABA and earlier e
>ngines ( all 1.8 l, 1.7 l and 1.6 l I-4 blocks ) both gas and diesel.
>Installation on the Vanagon I-4 gas or diesel engines requires removal of
>the
>oil pickup tube to put the gasket in place.
>
>The retail is $89 and I paid about $67 from Camelback. As I recall (it has
>been awhile), there was no advantage to buying from Tectonics and I like to
>support Camelback (as well as Bus Depot, Vanagain, etc). Check European Car
>as several vendors like German ... and Performance ... and Euro ...
>recently
>advertised the tray for as little as $55. Always insist on the part number.
>Many aftermarket and dealer parts operatives will insist the plastic oil
>pump pickup baffle is a windage tray. If you are quoted a price around $20
>to $30, this is what they are quoting you. Remember, this is the America
>doomed to continually repeat the Scopes Monkey trial!
>
>The windage tray strips the oil film from the crank and helps keep the oil
>pickup under oil during the most extreme conditions. It also has a direct
>effect on the extent to which the oil is aerated (foamed by the crank
>thrashing in the oil). The advantage of the windage tray is directly
>related
>to the oil viscosity and film strength. That is, if you are running
>molasses
>(SAE 50 or eq.) big effect, thin penetrating oil (SAE 0 W) then little
>effect.
>
>But what effect, you might ask? Well, the traditional value in HP at high
>rpm
>for racing engines is given as 3 to 5%. These numbers are for traditional
>engines where the static oil level is below the lowest point of the
>crankshaft. In the basic line of I-4 VW engines both transverse and
>longitudinal (remember, same offset angle) this is also the case. For the
>Vanagon mount angle with the diesel oil pan, the oil level (static and
>full)
>is at least 1.2 centimeters higher than in the rest of the I-4 family.
>There
>is a several mm overlap with the crank at the static position. (BTW, I have
>the full cross-sections of the I-4 mount in the Vanagon from the original
>German technical articles and will send them on to a web site when time
>permi
>ts). This means that in the hard-over mount condition, the effect is
>greater
>than the 3-5% standard effect. Now, my measurements:
>
>1. No horsepower difference measurements yet, but coming. By the
>notoriously
>unreliable seat-of-the-pants estimate, the engine spins up noticeably
>faster.
>
>2. No oil pressure light flash on hard braking or cornering. (Yep, had it
>before).
>
>3. Oil temperature at 5600 rpm under load, has dropped 12 degrees F.
>Probably
>due to lack of air in oil. This is for my standard 5W-40 synthetic oil.
>
>4. Amazing change in oil thrashing around in crankcase. As repeated in the
>next section, I put a borescope into the former dipstick hole and have a
>tape
>of the crank flying around and the agitation of the oil. I'll try to pull a
>few frames to show the key points, but its not the frothing shower it was.
>
>5. Finally, the gasket completely eliminated oil pan leaks.
>
>Second, on the issue of the oil dipstick port on all I-4 engines (other
>than
>the Vanagon diesel) which are mounted at the proper (engine cover
>conserving
>design). Caution!!! This is a most important issue although proper
>resolution
>is trivial. Remember that for Digifant II and CIS-E engines (I assume CIS
>is
>similar, but haven't really looked at this primitive system) the crankcase
>can only be ventilated via the PCV system. An air leak in the crankcase
>system will effect fuel economy significantly. If one uses the diesel oil
>pan
>and dipstick, this in-the-block dipstick port must be sealed. I cut the
>tube
>off about 10 cm. away from the block surface (Dremel tool). Then used HT
>PCV
>hose and clamp over the tube wall, and a long bolt (long enough to have
>non
>threaded portion - 8 or 10 mm bolt - same OD as dipstick tube) to close it
>off. I, on occasion, use this port to test modifications I have made
>(measuring crankcase pressure, adding video boroscope to examine engine
>while
>running, etc, etc). This clamped PVC hose approach has functioned
>perfectly.
>I have seen other conversions with pinched-off tubes, stuffed rags, bolt
>with
>permatex ... argh.
>
>One listee commented about complete removal and replacement with the oil
>dipstick tube used on the later diesels and turbo-diesels delivered other
>than in the USA. This will work if carefully done. In my correspondence
>with
>a German colleague, I was told that the bore in the block was different. So
>I
>did not investigate further. I saw one conversion where the owner cobbled
>up
>the dipstick system from the later waterboxers and crafted a Swagelock
>transfer between the WB parts and the I-4 dipstick tube. Bad. Had to
>calibrate actual oil level to get proper stick length. Dipstick often
>caught
>during insertion. ...
>
>Third, on the issue of rear battery location and engine heat. The comment
>that engine heat is not an issue is simply wrong. All diesels were
>delivered
>with engine area battery mounts. Indeed, as I have said previously, I run
>the
>primary and auxiliary battery in this area. For years since the original
>purchase in 1982, I had gone through batteries as fast as I went through
>starters. Maintenance free batteries. There is no problem if you
>religiously
>check battery water level with every other fill-up, but my Westfalia is
>always loaded or I'm in a hurry, etc. The engine compartment temperatures
>are
>so hot that the water level falls quickly. Sulfonation of the exposed
>plates
>occurs, and capacity falls. Generally no problem in the summer. Onset of
>late
>fall and early winter, temperatures drop and no battery capacity. OK if you
>have lifetime battery warranty, but the time and inconvenience add up. Wife
>thinks Vanagon has failed again.
>
>My solution: I built a thermal shield around the battery to minimize
>thermal
>transfer. The barrier seals to the engine cover and vents to the wheel
>well.
>The air flow from the side scoop ventilates the battery compartment. No
>loss
>of battery capacity since install several years ago.
>
>Fourth and last comment on statements about miserable engine mounts for the
>factor diesel mount cage (50 degree offset) vs. the Kennedy/Fast Forward 15
>degree mount. Balderdash say I. The vibration spectrum of the diesel makes
>that of its gas counterpart pale in comparison. From low frequency to high
>the amplitude and power spectrum of the diesel far exceeds the gas. Of
>course, the gas engine can spin to rates which would lead to piston/con rod
>extrusion through block events on the diesel (lots of short term
>vibration).
>The mount technology used by VW of passive vibration isolation through a
>rubber adsorber/isolator bonded to metal has about the same acoustic
>impedance for all I-4 VW engines. The compliance is different on the VR6
>and
>TDi engines given the torque impulse characteristics. As far as I know,
>no-one has adopted the proven vibration isolation technology pioneered by
>Porsche (liquid filled rubber mounts) or Citroen (coupled liquid logic
>rubber
>mounts). Therefore the reported I-4 vibration problems are not a function
>of
>mount angle and are not solved more effectively by an aftermarket solution
>as compared to the factory one. Afterall, the block mount points are the
>same, the engine cradle is rigid and there is no evidence to suggest that
>the
>possible difference in frame mount location is tuned to different
>resonances.
>Note, the factory mount is through one rubber set to the cradle, then the
>cradle mounts to the frame through two sets of rubber isolators. The front
>transmission mount is common to any system. Many of the aftermarket mounts
>I
>have seen are hard mounted to the frame and coupled to the engine through a
>single compliant mount. Vibration resonances are (in my experience) due to
>poorly mounted exhaust systems.
>
>Sorry for the length, hope this helps someone.
>
>Frank Grunthaner
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