| Author |  Topic  |
melle
V4 Guru
United Kingdom
3833 Posts |  Posted - 16 Dec 2014 : 14:51:17  
| How much end float should a distributor have? I have quite a few kicking about and they all seem to have quite a lot of vertical play considering timing and possibly gear wear. But if none of them are tight it might be OK? The workshop manual doesn't say anything about it as I suspect garages rather replaced than overhauled them anyway. I have rebuilt a few in the past and always shimmed them to 'what felt good', never actually measured anything but I guestimate they had about 0.3-0.4mm play left after the overhaul.
How do I correct the end float if needed? Shims in the distributor housing or between the housing and the drive gear?
I'm in my workshop by the end of the week and will measure all my dizzies then for reference.
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V |
Edited by - melle on 16 Dec 2014 14:59:33 |
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Woody
V4 Guru
United Kingdom
2763 Posts | Posted - 16 Dec 2014 : 19:40:37
| I would have thought that float would be governed by the intermeshing of the gears on the distributor and camshaft.
Can't say I have ever thought to check it other than observe if the axial play at the rotor arm was significant. Haven't experienced worn gears previously.
Have a few distributors in the garage so would have to do a test in the std engine to see what results were experienced.
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melle
V4 Guru
United Kingdom
3833 Posts | Posted - 16 Dec 2014 : 20:54:42
| I currently have about a dozen distributors I think and on some the gears are worn quite badly. I've also ditched a couple cams with badly worn gears in the past from engines I've broken. I'll take some photos when I'm in the workshop later this week. I sold a NOS distributor earlier this year, haven't thought of measuring its backlash before sending it off. Maybe the current owner, who is a forum member, can do that?
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V | |
|
Derek
V4 Guru
United Kingdom
2190 Posts | |
melle
V4 Guru
United Kingdom
3833 Posts | |
AlexW
V4 Fanatic
210 Posts | Posted - 18 Dec 2014 : 09:10:20
| | Have measured end float on new dizzy and its 0.85-1mm | |
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melle
V4 Guru
United Kingdom
3833 Posts | Posted - 18 Dec 2014 : 09:21:32
| Thanks a lot Alex, looks like most of mine aren't too far off then.
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V | |
|
Andyinthegarage
V4 Fanatic
United Kingdom
361 Posts | Posted - 18 Dec 2014 : 19:58:13
| | Could someone post a picture showing what that looks like as I am pretty sure that (with the dizzy installed) I can lift the rotor spindle by considerably more than that...Confused! | |
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ratty
V4 Fanatic
United Kingdom
340 Posts | Posted - 18 Dec 2014 : 21:14:26
| | I would have thought the phospher bronze bush that the bottom of the shaft runs in is more important. All of mine were worn with alot of side play so made a new one. | |
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melle
V4 Guru
United Kingdom
3833 Posts | Posted - 19 Dec 2014 : 10:05:35
| Not all dizzies have that bush. I've dismantled about six so far and most didn't have much radial wear, but rebushing is indeed the only way if they're worn. You shouldn't feel ANY side movement. I would say this is less important for running electronic ignition than points.
Andy, photo will follow.
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V | |
|
Andyinthegarage
V4 Fanatic
United Kingdom
361 Posts | Posted - 19 Dec 2014 : 19:50:58
| quote:
Originally posted by Andyinthegarage
Could someone post a picture showing what that looks like as I am pretty sure that (with the dizzy installed) I can lift the rotor spindle by considerably more than that...Confused!
Here's what I mean by "considerably more" - no different with original points fitted - first image is fully down, and second manually lifted...thoughts?
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melle
V4 Guru
United Kingdom
3833 Posts | Posted - 19 Dec 2014 : 22:06:02
| The shaft consists of two pieces, you're lifting the top piece. End float is measured between the housing and the gear.
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V | |
|
ianh
V4 Fanatic
United Kingdom
250 Posts | Posted - 19 Dec 2014 : 22:59:28
| | Hi Melle, How do you get the shaft and base plate out of the body? My distributor body has the crimps in the side that hold the base plate in position so I assumed that it didn't come appart. | |
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Andyinthegarage
V4 Fanatic
United Kingdom
361 Posts | Posted - 19 Dec 2014 : 23:56:15
| quote:
Originally posted by melle
The shaft consists of two pieces, you're lifting the top piece. End float is measured between the housing and the gear.
That's a relief. | |
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melle
V4 Guru
United Kingdom
3833 Posts | Posted - 20 Dec 2014 : 10:48:27
| Do you have the same type distributor as in my photo? The crimps on that one prevent the breaker plate from falling down. Only the older types are not meant to take apart, but where there's a will there's a way with those ones as well. Drive the roll pin out of the gear, pull the gear off the shaft, remove all screws, unhook the vacuum canister and remove the contents by gently tapping the shaft with an appropriate mallet. No hard blows are required, but you sometimes need to work things loose by pushing them up with a screwdriver through the vacuum can hole.
As you can see from above picture, I've learnt along the way. You can get everything out without removing the gear, but I wouldn't recommend doing so. Removing the pin and the gear can be a real pain though. Be very careful when dismantling a distributor, many parts are calibrated and the plastic bits might have become brittle.
1970 96V4 "The Devil's Own V4"
1977 95V4 van conversion project
1988 900i 8V | |
|
ianh
V4 Fanatic
United Kingdom
250 Posts | Posted - 20 Dec 2014 : 11:16:23
| | Thanks Melle, all dismantled as per your method. The screwdriver through the vacuum can hole was the secret, you're better than a Haynes manual. | |
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| Topic | |
Distributor end float
