Date: Tue, 29 Jul 2008 08:28:14 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: Different Kind Of Valve Adjustment Question? NOW What's next?
In-Reply-To: <20080729020754.57C452331F8@pop1.cfu.net>
Content-Type: text/plain; format=flowed
On the valve adjustment, it is normal and neccasary for the push rods to not
be under compression when the cyelinder is at top dead center on the
compression stroke. Proper adjustment is loosen the rocker, then take up the
slop and then tighten 1 to 2 turns, (not critical). The lifter will then
adjust and yes when you try again you wil be abloe to just turn the pushrod.
Remember the goal is that the valve has to fully close or else it will not
seal and will burn up. You can not just keep taking up the slack. After
screws are worn in, they really need to be repalced when adjusting or that
lousy angle will really beat up the valve stems.
As for your overheationg, with the thermostat removed low speed cooling will
be extremely poor. A lot of the coolant is simply running around the engine
in a circle. The small disc on the t-stat closes a bypass as the top disc
opens. The t-stat is not a simple open-shut set up. It is really a mixing
valve with the coolant constantly flowing to keep temparatures even
thrououht the engine.
What do you mean by warming up too quickly? Is it warming fast or
overheating? At idle is is normal for the engine to get warmer befroe the
radiator fan turns on. The thermostat begins to open at soem point above
87C. With the van not moving, the cooalnt from the radiator will warm up as
there is no air flow. Then the coolant temp in the engine wil raise, the
thermostat will open further. The radiator fan is controlled by a switch
sensiing the coolant in the radiator. Yes, by the time the coolant raises
and activates the switch, the coolant in the enigne should be hot enough to
fully open the thermostat and may be 10-15C higher than normal.
Dennis
>From: Max Wellhouse <dimwittedmoose@CFU.NET>
>Reply-To: Max Wellhouse <dimwittedmoose@CFU.NET>
>To: vanagon@GERRY.VANAGON.COM
>Subject: Re: Different Kind Of Valve Adjustment Question? NOW What's next?
>Date: Mon, 28 Jul 2008 21:07:06 -0500
>
>>Thanks to Jake and Scott and all that replied either publicly or
>>privately. Forthose of you just joining in, we're talking aout a
>>90GL 2.1 with a Haltech engine
>
>
>So far, the compression for cylinders 1, 2 and 4 is around 130 with
>1.5 turns and #3 is around 115. A day or two later while in WI., I
>pulled the rocker covers off and #3 had slipped to the point of the
>pushrods now spinning by thumb and index finger once more. I
>tightened them to 1.5 turns, but now I'm almost out of
>adjustment(rocker arm screw is pretty much flush with the jam nut)
>and I'm wondering if this could be both #3 lifters leaking
>simultaneously or whether both intake and exhaust valves are getting
>ready to fly or whether it's just worn adjuster screws. I have a
>feeling that the screws will be the cheaper fix, then lifters, then
>new heads or camshaft. At some point, a warm engine compression test
>with all plugs out and throttle body wide open has yielded higher
>compression readings than the 130.
>
>The motor's symptoms over vacation are as follows.
>1. With a new 87 degree thermostat in place and new radiator and a
>bled cooling system, the motor warms up way too quickly and has
>forced me to drive without the T stat for now. I do know of the
>consequences of doing that. I also replaced the Fan switch and have
>heard it run at low speed during idling and traffic. As I drive on
>the highway, as long as the water temp stays in the 100C range, the
>motor doesn't stumble very often, but if it gets below 90 C., then it
>will stumble more. Most stumbling occurs at about the time you would
>expect the accelerator pump to kick in if the engine were
>carburetted. It does stumble from a cold start, but not overly
>so. When stuck in traffic the motor still gets way too hot for my
>liking despite the Tstat being gone. Resuming to highway speeds
>cools things back down to normal.
>2. Engine power is not great and the motor will not idle under most
>circumstances. I have a VDO vacuum gauge hooked up to the dash and
>monitor it closely. Mopst of the highway driving at 60 or so with a
>moderate load of vacation gear would yield vacuum readings in the
>5-10 in. range. The times it does idle in the 1200rpm range the idle
>vacuum is in the 15in. range. I sprayed ether all over the normal
>leak-prone spots on the motor, and got no engine rpm rise, so I am
>assuming that a vacuum leak is not the problem. Low compression
>might be the reason for lack of vacuum. The trip up to Wisconsin, I
>had a mild tailwind and was getting over 19MPG, which is outstanding
>for this particular van. Even towing the 91 automatic shell back
>home, I got 15 despite all this other crap going on. The engine has
>never died or quit running for me, but my dash-mounted fuel pressure
>gauge has been reading about 5-6psi low at both idle and full
>power(24psi under high vacuum and maybe 30psi floored). I used a
>known good spare fuel pump and replaced both upstream and downstream
>fuel filters and no improvement. I wondered if the Fuel Pressure
>Regulator might be going bad, but it may not be getting enough vacuum
>to operate properly. I have a known good one I could swap.
>3. The thought has occurred to me that the O2 sensor might be toast,
>but the gas mileage isn't bad enough to have that problem is it? I
>don't know if I've replaced the O2 sensor since Boston Bob rebuilt
>the motor in 2001, so I guess it is possible that's one of the problems.
>
>4. The fuel injectors are the originals from 1990, but I didn't want
>to pull them out for testing while in the boonies in WI., for fear of
>ripping a seal that I couldn't replace. I should test them also for
>spray pattern and volume.
>
>5. I don't think the rebuilt Haltech unit is to blame either,
>although I've not tried to re-program it since it came back from AUS.
>
>Summary: The hot motor could be from a stealth air pocket, but the
>motor has been started and stopped enough now that I have no air at
>all in the expansion tank and the cap is a new blue one and the
>coolant level has stabilized in the overflow tank. The motor was
>running hot before the new radiator and fresh coolant, so the new
>parts didn't help there. I guess the low compression could be
>causing the hot motor issues too. I will test the O2 sensor although
>the Haltech sensor is a 3 wire and not the 4 wire like VW uses. The
>Haltech coolant temp and air temp sensors are only 3 months old, so I
>don't suspect them. The timing is right on as well.
>
>This maybe TMI, but better to offer too much.
>
>Thanks
>
>DM&FS
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