Distributor problem?
Thread Starter
Instructor
Joined: Sep 2015
Posts: 216
Likes: 16
From: Haverfordwest Pembrokeshire
Distributor problem?
I think I have a problem with the distributor on my 350, I've been trying for a while now to get to the bottom of oor running, since getting my car last year I've had problems getting it to go slowly smoothly.
I recently discovered my timing was miles out, in fact it was so far out I don't know how it ran at all!
I've finally got a smooth idle but at about 1200 rpm, any slower and the engine just dies, I've noted that when I try to slow down the idle the timing gets more erratic until the engine just stops, with the timing light on the marks are all over the place.
At first I thought maybe the springs had stretched but when I took the rotor off the springs were OK but there is a lot of backlash in the rotor shaft and if I twist it clockwise the shaft rises up a good 1/4" I'm sure this is not right?
As I'm in the UK I probably don't have as many options for rebuilding.
Thanks
Graham
I recently discovered my timing was miles out, in fact it was so far out I don't know how it ran at all!
I've finally got a smooth idle but at about 1200 rpm, any slower and the engine just dies, I've noted that when I try to slow down the idle the timing gets more erratic until the engine just stops, with the timing light on the marks are all over the place.
At first I thought maybe the springs had stretched but when I took the rotor off the springs were OK but there is a lot of backlash in the rotor shaft and if I twist it clockwise the shaft rises up a good 1/4" I'm sure this is not right?
As I'm in the UK I probably don't have as many options for rebuilding.
Thanks
Graham
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
I think I have a problem with the distributor on my 350, I've been trying for a while now to get to the bottom of oor running, since getting my car last year I've had problems getting it to go slowly smoothly.
I recently discovered my timing was miles out, in fact it was so far out I don't know how it ran at all!
I've finally got a smooth idle but at about 1200 rpm, any slower and the engine just dies, I've noted that when I try to slow down the idle the timing gets more erratic until the engine just stops, with the timing light on the marks are all over the place.
At first I thought maybe the springs had stretched but when I took the rotor off the springs were OK but there is a lot of backlash in the rotor shaft and if I twist it clockwise the shaft rises up a good 1/4" I'm sure this is not right?
As I'm in the UK I probably don't have as many options for rebuilding.
Thanks
Graham
I recently discovered my timing was miles out, in fact it was so far out I don't know how it ran at all!
I've finally got a smooth idle but at about 1200 rpm, any slower and the engine just dies, I've noted that when I try to slow down the idle the timing gets more erratic until the engine just stops, with the timing light on the marks are all over the place.
At first I thought maybe the springs had stretched but when I took the rotor off the springs were OK but there is a lot of backlash in the rotor shaft and if I twist it clockwise the shaft rises up a good 1/4" I'm sure this is not right?
As I'm in the UK I probably don't have as many options for rebuilding.
Thanks
Graham
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Definitely a problem with your distributor, the shaft is shimmed between the drive gear and the body, if my memory hasn't failed me this clearance should not be more than 25 thou.You need to pull the dist and investigate. Rebuild kits are available, bushes, new shafts tach drive etc so you should have no problem having it rebuilt or if originality is not an issue to you there are replacement distributors available at a cheaper cost than a rebuild of the original but most if not all made in the PRC where the manuf quality of some goods has question marks over it. I am in NZ and found it no problem to order the rebuild parts online I required, took about two weeks to get them.
Do you disconnect the vac can when checking the timing?
Do you disconnect the vac can when checking the timing?
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Is the vac can working?
Will it hold vacuum?
If you disconnect the hose from the vac can and plug it will your car idle down?
Will it hold vacuum?
If you disconnect the hose from the vac can and plug it will your car idle down?
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
If you have as you stated 1/4" of end play in the distributor shaft I am surprised it still runs. For every .013" of end play in the shaft and due to the helical gear you get a variance (or slop) of 1 degree of timing. With a quarter inch of shaft movement that would equate to just over 19 degrees of timing variance or slop. .250 divided by .013 = 19.23 degrees....
Time to pull the distributor and find what's going on as a quarter inch isn't just a shim problem.
Time to pull the distributor and find what's going on as a quarter inch isn't just a shim problem.
Thread Starter
Instructor
Joined: Sep 2015
Posts: 216
Likes: 16
From: Haverfordwest Pembrokeshire
Thanks everyone for your replies, I pulled the distributor today and there was almost 2mm of clearance between the drive gear and the end of the body casting, I've shimmed it up as suggested and things are now much improved, set the timing again and managed to get the idle down to about 800 rpm, timing now much more stable. Will see how it is on the road now, I'm guessing a lot better!
Just out of interest the markings on the distributor are 1111753 DelcoRemy6 A 10 inside there is a Mallory E Spark Performance Module Part No.6001M
Thanks again
Graham
Just out of interest the markings on the distributor are 1111753 DelcoRemy6 A 10 inside there is a Mallory E Spark Performance Module Part No.6001M
Thanks again
Graham
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