Date: Fri, 1 Jan 1999 07:13:30 EST
Reply-To: KENWILFY@AOL.COM
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: KENWILFY@AOL.COM
Subject: Re: warm up time? (longish)
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I have been wanting to address this subject for a while now. I try to always
allow some warm-up time for my van at least when I start it for the first time
each day.
Usually I go out and crank her up about 15 mins before I leave in the morning.
This does several things:
1. Allows oil to circulate in the engine without a load on the motor. The
worst thing you can do to your motor is go out, crank it up, and then start
revving it. Why? Depending on how long it has been sitting, there are some
parts that the oil has drained off of and others where is it thin. One of the
functions of oil is not only a lubricant but also a cushion to keep moving
parts away from each other. So when you rev the motor when it is cold you are
essentially pushing the crank pins down into bearings. This could cause
scoring or galling which, once it starts, makes little places in the bearing
surface where oil isn't distributed properly and therefore wear is accelerated
(translation: you are sitting by the side of the road cursing with a hole in
the case and then more profanity when the repair bills come in.) Allow the
oil temp to come up a bit before you really step on the gas.
2. Allows the engine to get up to operating temperature so that you have the
maximum clamping force on the head gaskets. Remember when I told you folks
that this time of year was head gasket blowing season? Well I hate to be
right about this but as several of you have painfully found out, it is. Why?
Expansion and contraction. The motor is colder now and therefore the initial
clamping force of the heads is lower now than it is in summer (another factor
is the "memory" of the rubber that is not used to the larger expansion
movements of cool weather). So when you crank up the cold motor you are
putting combustion chamber pressure (which is trying to push the heads off)
and coolant system pressure against a "looser" than normal head. If you go to
higher rpms during this time before the engine comes up to temps then you are
putting alot of pressure on the gaskets when they are the weakest (therefore
in some cases they give).
3. Allows the heaters to start working! Hey I am pretty unscientific when it
comes to this part. I hate to have to drive my van for 10 minutes before the
heat actually starts working. I try to turn the heater knob off so that the
motor can warm up faster, but it still takes a while.
Solutions:
1. Block heater. I would love to have one of these. You could plug in at
night into a timer that was set to turn the heater on 30 mins before you go
and it should be warm enough (at least here in NJ) so that you are getting
some heat right on startup. The oil flows better and everybody is happier.
Karl Bloss had a part number for one of these and I have meant to stock them
this winter but just haven't took the time to look into it. Just don't forget
to unplug when you drive away or people will be flashing thier lights and
honking at you and it won't be just 'cause your driving a Vanagon.
2. Remote starter. This is a good idea for those of us who are lazy and
don't want to go out in the cold to crank the van up in the morning. You can
only use these with autotranny Vanagons so it kinda limits them (I know that
you could use it on a stick one but I really don't like that idea). I have
seen these setups for $50 and have thought about getting one for my Carat.
3. Manual starter. You plan ahead so that you can start the van a little
while before you are ready to leave.
Sorry this one was long, and I am sure I missed some things. Just wanted
folks to be aware of what they are doing to thier motors.
Ken Wilford
Van-Again
John 3:16
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