Bizarro Timing Condition, '75 Westy

Busstom

Finally got the '75 Westy (more posts to come on that, later).

The PO's PO put a 009 on it (yes, the new SVDA is on it's way). Timing scale so faded it's unreadable (that's on the way too).

Out of curiousity, hit it with a timing light last night, and WOW! It's idling at 36 BTDC! Shocked

So, back it down....cough cough sputter...dies at 12 BTDC.

Theory: is it possible that some knucklehead put the fan on 120* out of clock, and the pulley on 90* off in the opposite direction, resulting in a net offset of 30 degrees?

Or is the fan keyed to the crank in only one orientation?

Can't wait to get home and tweak s'more...this one's driving me nuts.

Also thinkin' about putting a straight coat hanger into #1 hole and really finding TDC, just to find the neighborhood. Something's wonky on this one.

SGKent · Posted: Wed Sep 16, 2015 1:30 pm Post subject:

double check the timing light to be sure the knob to advance is not turned.

Also double check the pickup is on wire to #1 coming from the plug. Right side facing forward, farthest forward.
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airschooled · Posted: Wed Sep 16, 2015 1:35 pm Post subject:

Be aware that some aftermarket timing scales around 4* off in the "too advanced now buy a new engine" direction. Compare it with a known good OG unit before trusting it.
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busdaddy · Posted: Wed Sep 16, 2015 3:06 pm Post subject:

Here's how to confirm the mark is correct: http://www.ratwell.com/technical/FindTimingMark.html , if it only idles super advanced you may have a big vacuum leak.
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Tcash · Posted: Wed Sep 16, 2015 5:18 pm Post subject:

Finding True TDC
Tcash

Busstom · Posted: Wed Sep 16, 2015 11:24 pm Post subject:

Thanks for all the suggestions guys. I really thought I'd be posting about my first Type IV victory tonight, but...

After removing the fan, turned out it was assembled correctly, and when I reinstalled it, lined up the rotor and plug wires, and fired it up, sure enough, the dang thing won't run with normal timing.

Actually, it idles best when timed off the scale, to the left. Basically, the pulley notch is at the lower left mounting screw for the timing scale, which is somewhere between 40 and 50 degrees BTDC, I guess. The more I move it towards normal, the worse it runs, and dies around 16 BTDC.

busdaddy, I think you might be onto something with the vacuum leak theory. So would it be negligent to start spurting some starting fluid at the largest suspect areas? Heck, it could be anywhere at this point. Other than a couple small hoses here or there, most of the tubes and piping are all original. I don't even know where to start (FWIW, I have been reading Atwell's pages for weeks now...can't remember right off hand his talk about finding vacuum leaks).

Tcash: cool tool, now that you pointed that out, seems I've seen that concept somewhere, years ago...totally forgot about that ingenious hack.

Wildthings · Samba Member Joined: March 13, 2005 Posts: 50352

At a minimum verify that you are actually at TDC. Align the rotor with the notch on the distributor and verify that this is also where the wire for the #1 spark plug is. Now remove the 3-4 valve cover and watch the valves on the #3 cylinder. At TDC they should both be barely open and when you rock the engine back and forth a bit one should be closing and the other opening. If this condition is not met you are not at TDC and maybe your pulley is not aligned correctly on the crankshaft.

Tcash · Posted: Thu Sep 17, 2015 9:22 am Post subject:

Are you sure your timing light is on #1 and if it is how do you know?
Good luck
Tcash

Busstom · Posted: Thu Sep 17, 2015 11:20 am Post subject:

I know, the basic things seem like the most obvious causes.

Simple stuff: #1 wire is on #1 plug, which is front-most on passenger side of vehicle. Physically, position the crank (and crank pulley mark) at scale TDC, and the rotor is pointing to #1 position in cap, which correlates with #1 plug wire. Try inductive pickup on #2, and strobe hits timing mark 180 opposite, as would be expected. In other words, all indications are that the engine was assembled properly, including the pulley/fan, and even the notch on the distributor body is at #1 (as trivial as that is).

I validated the pulley/fan orientation per Atwell pages, all is good there. Reinstalling, I took particular caution to ensure the hole in the hub boss aligned on the dowel pin on the crank snout for proper fan orientation. I "sort of" did the Wildthings concept to verify true physical TDC for #1 piston, except I didn't check the #3 valves as he suggested, I checked the free valves at #1, as if I was doing a valve adjustment. All last night after work. I didn't bother fabbing the spark plug tool for TDC, cuz I didn't realize that T-IV plugs were so damn buried in the tin. The problem with the way I checked #1 valves for TDC is that it could actually be way after TDC and still have valves with full clearance, since valves are closed through the power stroke. But my problem is BTDC.

Oh, and my timing light is an old school (like me Laughing

) Sun brand (made in USA) and doesn't have an "advance" knob of any sort.

After work, I will try Wildthings' method for physical verification of the crank position. Remember, I'm only off by 30-ish degrees, not 90 or 180...if it were off 90 or 180, then the potential cause(s) would be way more obvious.

Off work in 3 hours...more to come!

SGKent · Posted: Thu Sep 17, 2015 11:43 am Post subject:

my concerns would be:

1) you don't have the correct mark or pulley. Must verify with the piston at TDC

2) The mixture is so lean and the fuel molecules so far apart they need the extra time to burn. This would indicate old fuel or a vacuum leak as BusDaddy suggested.

3) if it really is that advanced, and you leave it so far advanced it will destroy the engine.

You might be able to use something like this to see TDC thru the spark plug hole http://www.harborfreight.com/digital-inspection-camera-61839.html

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Tcash · Posted: Thu Sep 17, 2015 12:26 pm Post subject:

Have to cover the basics. Sounds like you have the light on #1.
As BD said a big vacuum leak. As you retard it, you should hear it sucking like a vacuum cleaner.
A vacuum gauge or Smoke tester would show it.
http://www.thesamba.com/vw/forum/viewtopic.php?p=7568752#7568752

Just to confirm your mark.
Note where the key way is located in the fan, in the middle of the two bolt holes.
When the inner mark on the pulley is lined up with '0' the key way should be in the orientation as pictured.

Image may have been reduced in size. Click image to view fullscreen.

Good Luck
Tcash

1967250s · Samba Member Joined: May 02, 2007 Posts: 2137

Is it possible the keyway is missing the key for the hub?
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Tcash · Posted: Thu Sep 17, 2015 9:08 pm Post subject:

OUCH

Busstom · Posted: Thu Sep 17, 2015 11:29 pm Post subject:

Busstom · Posted: Thu Sep 17, 2015 11:35 pm Post subject:

1967250s · Samba Member Joined: May 02, 2007 Posts: 2137

Don't be hasty. Check your compression and the keyway before jumping off any cliffs.
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Wildthings · Samba Member Joined: March 13, 2005 Posts: 50352

SGKent · Posted: Fri Sep 18, 2015 6:14 am Post subject:

(1) You may not even have a valve problem if you are off on TDC because of issues like a broken fan key or because you are looking at the wrong mark.

(2) if in the end you do have a valve problem, and if the heads have to come off because of it, you can verify TDC then.

In the meantime verify this is what you are looking at. This is the timing mark on my 1977 2L. Yellow arrow points to the correct mark used for alignment with scale.

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Tcash · Posted: Fri Sep 18, 2015 10:49 am Post subject:

The pic was to diminstrate where the key way is located. When the fan belt inner mark is lined up with (0).
Good luck
Tcash

Before you go any further you need to:
Test for vacuum leaks
Adjust your valves
set the dwell
then time it.

Busstom · Posted: Wed Sep 30, 2015 12:23 pm Post subject:

Hey all,

I just wanted to plug in an update so you all didn't think I rolled up and died, or just gave up on this Bus.

To recap: '75 Westy, just purchased, only runs 40* BTDC, needs full examination, wildy out-of-spec valves.

So, juggling the new puppy and home remodel, I've finally gotten this far:
1) pulled #1 plug (yeah, pretty easy), and low-and-behold, you can see the piston top down below! Okay, TDC confirmed, pulley/fan all good, everything all good there, TDC is TDC on #1 as indicated. Closed issue.
2) Proceeding with valve adjustment...super wonky gappage, screws need to be so far in that there's no more thread left for the jam nut. So ordered lash caps from CE, as temporary gap-fillers where needed, until I can just get the thing running and do more in-depth diagnosis - I'll tear it down if need be.
3) In culling the forum and Ratwell for info, got curious, pulled a pushrod and measured it...what the heck??? Stuck a magnet and guess what???

Yep, hydraulic lifter setup, in my '75! DOES THIS MEAN IT'S A 2L ALSO?

The only thing to do is literally pull a lifter to confirm, but how else could it be running 261-ish millimeter pushrods, right?

So thinking back, the seller told me that his brother (the real PO) had this Bus sitting for 9 years. This looks to be shaping up as a classic case of multiple stuck lifters, no?? So onward with that process.

But I wanted to throw this in, as many of you probably already know: Dan at CE is one hell of a helpful guy...cuz not only am I a Bay noob, I'm a hydro-lifter noob on air-cooleds. I hadn't done business with Dan in five years, but his patient and helpful perspective has assured him repeat business down the road.

Out!


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