TheSamba.com :: View topic - Experiences with a bad fuel pump and timing an 009

Mon Apr 15, 2013 8:12 am

And how many degres BTDC was it showing @3500?

Mon Apr 15, 2013 8:29 am

mmmm - 30-32, give or take a degree; kind of tricky to hold the car steady at 3500 RPM using the timing light's display and toggle it back and forth btn RPM and the timing setting, while turning the distributor.

Mon Apr 15, 2013 9:12 am

vamram wrote: mmmm - 30-32, give or take a degree; kind of tricky to hold the car steady at 3500 RPM using the timing light's display and toggle it back and forth btn RPM and the timing setting, while turning the distributor.

Why keep the rpm steady? Just rev it up until the timing light quits advancing and see what the timing reads. If this occurs at 3200rpm then fine, or it if happens at 3800rpms then fine. The exact rpm doesn't matter, I can't ever remember checking the exact rpm when doing this it just isn't required.

Mon Apr 15, 2013 9:16 am

Wildthings wrote: vamram wrote: mmmm - 30-32, give or take a degree; kind of tricky to hold the car steady at 3500 RPM using the timing light's display and toggle it back and forth btn RPM and the timing setting, while turning the distributor.

Why keep the rpm steady? Just rev it up until the timing light quits advancing and see what the timing reads. If this occurs at 3200rpm then fine, or it if happens at 3800rpms then fine. The exact rpm doesn't matter, I can't ever remember checking the exact rpm when doing this it just isn't required.
X2, I watch the mark as I rev and stop increasing a little after the mark stops just to make sure that's all it's going to do.

Mon Apr 15, 2013 9:49 am

So if I set the timing light to say 30 at 3500 RPM but the car wants to keep advancing to say 35, then that's what I should set the timing to? 35?

Couldn't that be indicative of something wrong if the timing can go so high - say bad distributor or something else?

Apologies if my question is off the wall, i'm a social worker by profession, backyard mechanic cuz I luv my VDubs.

Mon Apr 15, 2013 10:13 am

vamram wrote: So if I set the timing light to say 30 at 3500 RPM but the car wants to keep advancing to say 35, then that's what I should set the timing to? 35?

Couldn't that be indicative of something wrong if the timing can go so high - say bad distributor or something else?

Apologies if my question is off the wall, i'm a social worker by profession, backyard mechanic cuz I luv my VDubs.

No you set your timing at 28-30° BTDC with the hoses off at full mechanical advance. The exact rpm doesn't matter. If the timing keeps advancing past 3500 rpm, to say 3800 rpm then set your timing at 3800 rpm. Best to just forget the tach and just rev it until the timing doesn't advance anymore.

Mon Apr 15, 2013 10:39 am

vamram wrote: So if I set the timing light to say 30 at 3500 RPM but the car wants to keep advancing to say 35, then that's what I should set the timing to? 35?

Couldn't that be indicative of something wrong if the timing can go so high - say bad distributor or something else?

Apologies if my question is off the wall, i'm a social worker by profession, backyard mechanic cuz I luv my VDubs.

If the timing wants to advance beyond your max point, you bring it back to where you want it to be *after* it has told you where it wants to go.

If you only check it at your check point, you may not find out that it wants to go further. Go find where it may want to go, then bring it back so that it never ever goes past 28* @ specified rpm.

Think of it as a wayward child. If you only catch the kid at the front door at 3:00AM, you'll never know that he was going to a heroin rave . . . next door at Mrs. Smith's house??
Colin

Mon Apr 15, 2013 10:48 am

Colin - Heroin rave? Yikes. Sounds like i'll be catching him at the door at 30-32 degrees since he's an SVDA rather than bothering to wait for him to get next door (to 35? 38? etc). Whereas the others suggest the heroin rave might not be so bad....now i'm really confused. :?

Mon Apr 15, 2013 12:08 pm

Set your timing light to 28 and watch the mark on the pulley as you rev, keep increasing the RPM until the mark stops advancing, increase the RPM some more just to confirm it doesn't want to advance any more, the timing mark should be at the case split when it stops advancing. If it's short let go of the throttle and twist the distributor a little bit CCW when viewed from the top and try it again (watch out for the fan belt), if it goes past twist CW, keep doing fine adjustments until it stops at the mark and make sure the dial on the back of the timing light didn't get bumped, then tighten the distributor nut (not so much that it bends the clamp please) and try it one last time to confirm. Then hook the hose back up.

Mon Apr 15, 2013 1:35 pm

So this is on a '72 super beetle and not a bus? :D That's OK since there are more bus people that know how to time it right than there are bug people.

vamram wrote: it took me a while to find TDC,
Since it's evidently a bug motor you can go a tad more advanced on the timing. But just stick to 30 degrees BTDC Max. to be safe. Now for the big question- this timing mark, what is it and where is it? Evidently a notch on the pulley if it's a stock steel pulley. But which notch and why do you think it's actually at the one and only TDC?

Mon Apr 15, 2013 1:59 pm

Yeah, I know it's bus forum, I got caught up in it because the original issue mirrored what I was experiencing on the bug. Didn't mean to hijack it...just sort of evolved...and y'all are very welcoming!

Anyway - it's a stock steel pulley w/a single notch. I found TDC by using the pencil trick in the #1 cylinder and matching where it was to the notch on the pulley and the #1 location on the distributor.

Mon Apr 15, 2013 2:14 pm

vamram wrote: I found TDC by using the pencil trick in the #1 cylinder

So then you might be at least within 6 or 8 degrees of the REAL TDC. Don't count on in being any more accurate that that. Unless your pulley has the evasive dimple that very few had (I've never seen one) you need to get a little (lot) more sophisticated in how you determine it.

Mon Apr 15, 2013 3:43 pm

Desertbusman wrote: vamram wrote: I found TDC by using the pencil trick in the #1 cylinder

So then you might be at least within 6 or 8 degrees of the REAL TDC. Don't count on in being any more accurate that that. Unless your pulley has the evasive dimple that very few had (I've never seen one) you need to get a little (lot) more sophisticated in how you determine it.
Agreed, got any friends you can borrow a degree pulley from?, put that on at TDC and carefully slide it off, then install yours and make a mark if what's on there now doesn't line up (a mark at 32 using the same procedure wouldn't hurt either :wink: ).

Mon Apr 15, 2013 4:56 pm

I've got a degree pulley for the car, just haven't put it on yet. I've used one of the degree pulley paper templates too on my '64. Maybe i'll try that here first?

Mon Apr 15, 2013 5:03 pm

It usually takes 10 minutes to pop your pulley off and slip that degree wheel on temporarily, nothing better than positive engagement with the crank key to tell you exactly where the marks should be.

Mon Apr 15, 2013 5:57 pm

Temporarily? Why not just leave the degree pulley on? :?:

Mon Apr 15, 2013 6:09 pm

vamram wrote: Temporarily? Why not just leave the degree pulley on? :?:

If it's a sunday afternoon and no local parts houses are open, so you borrow one from a friend but (s)he demands it back that night! 8)

Mon Apr 15, 2013 10:25 pm

vamram wrote: I've got a degree pulley for the car, just haven't put it on yet. I've used one of the degree pulley paper templates too on my '64. Maybe i'll try that here first?

If you have one why havn't you put it on yet? Just go ahead and do it if you really want to time your engine. :wink:

Next- Forget about the paper template. All it will do is get you fhe 30* from some unknown assumed zero degrees location. The end point obviously is no more accurate than the starting point.

BTW, if no degree pulley then there is a $10 piston stop tool for the spark plug hole that you can use to accurately find the exact TDC. Providing the special proceedure is closely followed.

If you do have a degree pulley to put on it then double check the bolt length. Some aluminum pulleys require a longer crankshaft bolt.

Tue Apr 16, 2013 6:55 am

I haven't put it on yet cause i'm chicken. Never done it before and don't want to screw it up. I plan on following the Bentley manual instructions for changing it w/the engine IN the car....

Do you have a link for the TDC-finding tool?

Tue Apr 16, 2013 11:04 am

vamram wrote: Do you have a link for the TDC-finding tool?

Here is the type of tool that you can use. Seems like Amazon sells quite a few different brands and designs. I've never bought one since I made one from a spark plug and a thumb screw. http://www.amazon.com/Competition-Cams-4795-Center-Bolt-Style/dp/B000CIOA0Q/ref=pd_bxgy_auto_img_y

Keep in mind that the tool is only good providing that you use it correctly. Here's how-

- Put it in #1 plug hole with the stop screwed most of the way out.
- Turn the crank back and forth thru the expected/estimated TDC range with the piston at the top of the stroke.
- Turn the stop in carefully until it just slightly contacts the piston as you rock the crank back and forth.
- Rotate the crank a few degrees in either direction to pull the piston inward.
- Screw the stop inward a couple turns.
- Carefully rotate the crank to extend the piston outward until it lightly but firmly contacts the piston.
- Accurately mark the pulley at the case parting line.
- Rotate the crank in the opposite direction almost a full revolution until the piston again contacts the stop with the same light firmness.
- Again mark the pulley at the case parting line.
- Carefully put your new accurate TDC mark on the pulley exactly 1/2 way between your 2 stop marks. Bingo!

A Note Of Caution: When you turn the crank CCW and if the distributor is removed the drive gear is apt to walk up the tooth engagement and jump a tooth. Except for finding this TDC and particularly with a T-1 engine it's wise to be in the habit of only turning the crank CW. Numerous reasons.