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stegosaurus Sat Feb 01, 2020 5:16 am

1983.5 2.1 rebuild on Digijet FI (not Digifant)

I am totally confused! The rebuilder is very adamant that the timing should be 35 at 3k. On the other hand, I have had knowledgeable Samba members tell me that it should be timed as if it were a 1.9. I also have seen a few threads here on the Samba but no conclusive answers. Is it the engine size that determines the timing or fuel injection system. Right now it's timed at 35 and it runs terrible!

4Gears4Tires Sat Feb 01, 2020 6:30 am

Did you time it off the first or second mark?

And IIRC, the 2.1 and the 1.9 have different crank pulleys which means you need to time them to the engine, not the management.

zimflux Sat Feb 01, 2020 6:42 am

35 at 3-3.5k rpm at top dead center. The actual RPM is whenever the mark is stabilized.

Doesn't matter which engine but you do need to make sure using the right mark on the pulley.

Follow information you've read from 10cent.

stegosaurus Sat Feb 01, 2020 6:42 am

4Gears4Tires wrote: Did you time it off the first or second mark?

And IIRC, the 2.1 and the 1.9 have different crank pulleys which means you need to time them to the engine, not the management.

It's a 2.1 with a 1.9 pulley. It's been timed at 35 at 3k. My pulley has the 5 mark to the left of the larger TDC not to the right. Im using the TDC mark for reference with a timing gun that has the advance feature.

stegosaurus Sat Feb 01, 2020 6:52 am

zimflux wrote: 35 at 3-3.5k rpm at top dead center. The actual RPM is whenever the mark is stabilized.

Doesn't matter which engine but you do need to make sure using the right mark on the pulley.

Follow information you've read from 10cent.

I've read the 10 write up. Are you referring the the total advance at 40? I've had trouble getting it that far down. The disributor won't physically move enough clockwise. In other words the distributor just stops rotating enough to get it at 40 @ 3 to 3.5k.


https://www.thesamba.com/vw/forum/viewtopic.php?t=...Gd84o692YU

Ahwahnee Sat Feb 01, 2020 7:20 am

FWIW, I have a 1.9 Digijet rebuilt as a 2.2 and am running 5* ATDC @ idle and 40* BTDC at 3000 RPM.

I've had it like that for 60,000 miles with no problems and MPG in the low 20s.

If you don't have enough swing room to get where you want to be you may need to reposition the distributor.

stegosaurus Sat Feb 01, 2020 8:29 am

Ahwahnee wrote: FWIW, I have a 1.9 Digijet rebuilt as a 2.2 and am running 5* ATDC @ idle and 40* BTDC at 3000 RPM.

I've had it like that for 60,000 miles with no problems and MPG in the low 20s.

If you don't have enough swing room to get where you want to be you may need to reposition the distributor.

Ok. How would I go about repositioning?

zimflux Sat Feb 01, 2020 9:45 am

stegosaurus wrote: zimflux wrote: 35 at 3-3.5k rpm at top dead center. The actual RPM is whenever the mark is stabilized.

Doesn't matter which engine but you do need to make sure using the right mark on the pulley.

Follow information you've read from 10cent.

I've read the 10 write up. Are you referring the the total advance at 40? I've had trouble getting it that far down. The disributor won't physically move enough clockwise. In other words the distributor just stops rotating enough to get it at 40 @ 3 to 3.5k.


https://www.thesamba.com/vw/forum/viewtopic.php?t=...Gd84o692YU

Yes, all in. Everything connected. TDC on 1.9 pulley is U mark farthest from engine.

Please provide picture of distributor. What are you currently timed at all in/total advance?

I'm assuming there's no issue with using 1.9 pulley on a 2.1 engine... No experience with such.

Ahwahnee Sat Feb 01, 2020 9:47 am

I haven't re-positioned the one on the van but on other cars it was simply a matter of withdrawing the distributor and drive shaft then re-engaging the shaft off by one tooth (in the direction you need to go).

Wait for someone with specific WBX experience as it may be different or (I seem to recall) there may some precaution you have to take as you withdraw it.

stegosaurus Sat Feb 01, 2020 9:51 am

zimflux wrote: stegosaurus wrote: zimflux wrote: 35 at 3-3.5k rpm at top dead center. The actual RPM is whenever the mark is stabilized.

Doesn't matter which engine but you do need to make sure using the right mark on the pulley.

Follow information you've read from 10cent.

I've read the 10 write up. Are you referring the the total advance at 40? I've had trouble getting it that far down. The disributor won't physically move enough clockwise. In other words the distributor just stops rotating enough to get it at 40 @ 3 to 3.5k.


https://www.thesamba.com/vw/forum/viewtopic.php?t=...Gd84o692YU

Yes, all in. Everything connected. TDC on 1.9 pulley is U mark farthest from engine.

Please provide picture of distributor. What are you currently timed at all in/total advance?

I'm assuming there's no issue with using 1.9 pulley on a 2.1 engine... No experience with such.

It will only go to 35 at 3000


stegosaurus Sat Feb 01, 2020 10:01 am

Distributor is a NOS from Vanagain. The retard canister came with it.

Ahwahnee Sat Feb 01, 2020 10:39 am

stegosaurus wrote: ...It will only go to 35 at 3000



I think the swing room is just a matter of how it was assembled when installed.

Mine at 40 advance:


stegosaurus Sat Feb 01, 2020 10:51 am

/\ I'll give it a shot. Maybe it's the canister with vacuum hoses getting in the way?

Jake de Villiers Sat Feb 01, 2020 2:19 pm

stegosaurus wrote: /\ I'll give it a shot. Maybe it's the canister with vacuum hoses getting in the way?
Yeah. So you unbolt the distributor, rotate the housing clockwise and re-insert. Re-time correctly. Zoom-zoom.

tencentlife Sat Feb 01, 2020 4:12 pm

Jake de Villiers wrote: stegosaurus wrote: /\ I'll give it a shot. Maybe it's the canister with vacuum hoses getting in the way?
Yeah. So you unbolt the distributor, rotate the housing clockwise and re-insert. Re-time correctly. Zoom-zoom.


Yeah-uhh, no, it doesn't work that way.

To get more room for the dist. to add more advance, what has to be done is remove the dist., then lift out the dist. drive pinion until it's disengaged from the crankshaft spiral gear, turn pinion one tooth clockwise and reinsert. Then loosen the dist. timing clamp and reinstall, rotating the clamp so it drops over the hold-down stud. Retime by eyeball to get started, then tune with a strobe.

This is a simple and quick thing to do if you know what you're doing, but if you don't, while attempting to extract and replace the drive pinion you can royally F some things up inside the engine in ways that will require a full overhaul to correct. I would advise the OP to go to someone familiar with the procedure.

stegosaurus Sat Feb 01, 2020 5:17 pm

tencentlife wrote: Jake de Villiers wrote: stegosaurus wrote: /\ I'll give it a shot. Maybe it's the canister with vacuum hoses getting in the way?
Yeah. So you unbolt the distributor, rotate the housing clockwise and re-insert. Re-time correctly. Zoom-zoom.


Yeah-uhh, no, it doesn't work that way.

To get more room for the dist. to add more advance, what has to be done is remove the dist., then lift out the dist. drive pinion until it's disengaged from the crankshaft spiral gear, turn pinion one tooth clockwise and reinsert. Then loosen the dist. timing clamp and reinstall, rotating the clamp so it drops over the hold-down stud. Retime by eyeball to get started, then tune with a strobe
This is a simple and quick thing to do if you know what you're doing, but if you don't, while attempting to extract and replace the drive pinion you can royally F some things up inside the engine in ways that will require a full overhaul to correct. I would advise the OP to go to someone familiar with the procedure.

Sounds way over my head. I wouldn't attempt it without supervision thank you. But this brings up a question. Because I can't get it to go any further does this indicate a problem? Should it have the ability to go clockwise further?

Ahwahnee Sat Feb 01, 2020 5:59 pm

stegosaurus wrote: ...Because I can't get it to go any further does this indicate a problem? Should it have the ability to go clockwise further?

Not really. There is a limit to how far the distributor can be turned either way - and that becomes the range of adjustment. At that point the vac canister bumps into something (the head casting or the blanking plate stud perhaps).

That range is enough if the distributor is installed in a particular position. Off a tooth from that position and it may be unable to turn far enough to get as much advance as you want.

Wildthings Sat Feb 01, 2020 11:02 pm

The proper Digijet timing is 28 +/- 2 BTDC @ 3800+rpms with the hoses removed and plugged, just like for an aircooled with a dual advance distributor. Removing and turning the distributor drive is easy enough, everyone has a first time at doing this. You can use a dowel rod jammed down in to the center bore in the drive, a magnet, or a pair of duck billed snap ring pliers to raise the drive. A properly sized dowel rod 5/16"(?) will probably give the best feel. Slowly raise the drive turning it slightly as you raise it and keep testing to see if it has disengaged and will turn free. Once the drive turns rotate it about 30 and carefully let it drop down into place.

Make sure the dog on the bottom of the distributor shaft mates with the slot on the drive when reinstalling the distributor.

When doing this work DO NOT remove the plug wires from the cap, but just set the cap aside with the wires still attached. Removing the coil wire is fine.

If you have an advance style timing light you will be using the U shaped timing mark. If you do not have an advance style timing light you will need to make a new mark 1 9/16" to 1 5/8" to the right of the U shaped mark.

stegosaurus Sun Feb 02, 2020 8:54 am

Ahwahnee wrote: stegosaurus wrote: ...Because I can't get it to go any further does this indicate a problem? Should it have the ability to go clockwise further?

Not really. There is a limit to how far the distributor can be turned either way - and that becomes the range of adjustment. At that point the vac canister bumps into something (the head casting or the blanking plate stud perhaps).

That range is enough if the distributor is installed in a particular position. Off a tooth from that position and it may be unable to turn far enough to get as much advance as you want.

So it appears that I can get a little more advance if I take the hose off the canister. With it on it it's stopped because of the fuel pressure regulator. Im going to try and work around that and see if that little more helps. I'll report back.

Wildthings Sun Feb 02, 2020 9:27 am

stegosaurus wrote: Ahwahnee wrote: stegosaurus wrote: ...Because I can't get it to go any further does this indicate a problem? Should it have the ability to go clockwise further?

Not really. There is a limit to how far the distributor can be turned either way - and that becomes the range of adjustment. At that point the vac canister bumps into something (the head casting or the blanking plate stud perhaps).

That range is enough if the distributor is installed in a particular position. Off a tooth from that position and it may be unable to turn far enough to get as much advance as you want.

So it appears that I can get a little more advance if I take the hose off the canister. With it on it it's stopped because of the fuel pressure regulator. Im going to try and work around that and see if that little more helps. I'll report back.

You could try rotating the wires around the cap by 90 and see if this will allow you to set the timing. You will of course need to turn the distributor body close to 90 to get the timing even close after doing this.



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