Dizzy advice, Distrubutor Options

[ILM914]

Hello all: I just installed a used distributor on my 74 2.0, when I removed the old one I turned the engine so the rotor pointed toward the # 1 spark plug/notch on the dizzy rim then removed it and installed the new/used dizzy. Here's what seems diff from the old to new dizzys. when timing with the strobe light I turned the dizzy farther counter clockwise than the older one. Now instead if the plug for the trigger points being dirctly behind the dizzy it faces about 10 oclock(towards the driver. Does that seem right? Also the timing mark from idle to 3500 rpm only moves a quater inch when i do the timing. Does that sound right? I think my old dizzy had more timing mark movement with the rpm changes. I backed the idle adjustment screw oll the way in to it's lowest point and the lowest i could get it to go was the 1100 rpm. Wondering why that is. I could get it lower before. Thank you everyone, Joe

[Cap'n Krusty]

Part numbers of the distributors? All things considered, the swap should be a drop-in, unless the drive tang has been off and replaced 180 out, but that doesn't fit this scenario. Any T4 FI distributor should be the same.

The Cap'n

[TheCabinetmaker]

Why did you swap them? Is the diz the same# as the old one?

[ILM914]

Thanks the part #s were different, I haven't written down the part # on the new one, but they look identical. The car is running fine it's just that it's set more counter clockwise than the old one and I can't get the idle to go below 1100 rpm. if you have a stock 74 motor set right is the trigger point plug on the back of your distributor at 12 o'clock from front to back straight line of the car, or does it at 10 o'clock? and like said when I strobe time it, from idle to 3500 rpm the mark only moves maybe a 1/4 inch (not much) does that sound right? thank you very much this is a great bunch of folks on this site Joe

[TheCabinetmaker]

The diz needs to be paired to the ecu and other components. Brad anders site has a chart with the matching components numbers. Not sure if that is the problem. sounds more like the diz is off by one notch.did you disturb the drive gear under the diz?

[Prospectfarms]

Thanks the part #s were different, I haven't written down the part # on the new one, but they look identical. The car is running fine it's just that it's set more counter clockwise than the old one and I can't get the idle to go below 1100 rpm. if you have a stock 74 motor set right is the trigger point plug on the back of your distributor at 12 o'clock from front to back straight line of the car, or does it at 10 o'clock? and like said when I strobe time it, from idle to 3500 rpm the mark only moves maybe a 1/4 inch (not much) does that sound right? thank you very much this is a great bunch of folks on this site Joe

If you know that the part #'s between old and new distributors don't match, you've probably answered the questions on the rest of your post in the negative. Most Bosch distributors I've seen look pretty similar, but they can be quite different in operation. Here's the link to the page ILM 914 mentioned containing Bosch part # for different 914 applications. http://members.rennlist.com/pbanders/DJetParts.htm

[ILM914]

Thanks, no the motor did not turn can you tell me how I can get to that data base with the part #s? and get more info on this? I seem to have hit a dead end on this site Thanks, Joe

Hello all: I just installed a used distributor on my 74 2.0, when I removed the old one I turned the engine so the rotor pointed toward the # 1 spark plug/notch on the dizzy rim then removed it and installed the new/used dizzy. Here's what seems diff from the old to new dizzys. when timing with the strobe light I turned the dizzy farther counter clockwise than the older one. Now instead if the plug for the trigger points being dirctly behind the dizzy it faces about 10 oclock(towards the driver. Does that seem right? Also the timing mark from idle to 3500 rpm only moves a quater inch when i do the timing. Does that sound right? I think my old dizzy had more timing mark movement with the rpm changes. I backed the idle adjustment screw oll the way in to it's lowest point and the lowest i could get it to go was the 1100 rpm. Wondering why that is. I could get it lower before. Thank you everyone, Joe

[underthetire]

Sounds to me like the mechanical advance is stuck inside the dizzy. You should see more timing changes than 1/4", and that would also explain the rotation change.

[jcd914]

It sounds to me as if the distributor you installed has a broken centrifugal advance, that is mostly advanced at idle. That would explain why your distributor position is so different and why you get so little change in the timing mark as you go from idle to 3500rpm. Maybe springs are missing or broken or the weights are binding.
You never did answer the question of Why you change the distributor in the first place? What was the problem you were trying to fix?
Also you get so little change in the timing mark as you go from idle to 3500rpm and you set the timing at 3500rpm then the timing at idle has to way too far advanced. This would explain your high idle speed and I would expect you to get pinging/knocking under load at low rpm (this could be very bad very quickly).
Follow the link in Prospectfarms post to Paul Anders web site and distributor numbers are listed 1/8 of the way down the page.

Jim

[914_teener]

It sounds to me as if the distributor you installed has a broken centrifugal advance, that is mostly advanced at idle. That would explain why your distributor position is so different and why you get so little change in the timing mark as you go from idle to 3500rpm. Maybe springs are missing or broken or the weights are binding.
You never did answer the question of Why you change the distributor in the first place? What was the problem you were trying to fix?
Also you get so little change in the timing mark as you go from idle to 3500rpm and you set the timing at 3500rpm then the timing at idle has to way too far advanced. This would explain your high idle speed and I would expect you to get pinging/knocking under load at low rpm (this could be very bad very quickly).
Follow the link in Prospectfarms post to Paul Anders web site and distributor numbers are listed 1/8 of the way down the page.

Jim

(IMG:style_emoticons/default/agree.gif)

Also check the vacum advance/retard diaphram for leakdown.

Mine leaked causing a high idle.

Sounds like you may have several issues.

Verify TDC and pull and check the dizzy.

[ILM914]

Thanks guys I changed the dizzy because the gearings were failing and the screw plate threads was striped. sounds like the used dizzy I purchased may be bad. the car is running well, just idles at 1100. Thanks

[Cap'n Krusty]

Thanks guys I changed the dizzy because the gearings were failing and the screw plate threads was striped. sounds like the used dizzy I purchased may be bad. the car is running well, just idles at 1100. Thanks

"The gearings were failing". Interesting. What does it mean?

The Cap'n