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-   -   Distributor/Timing Problems (https://67-72chevytrucks.com/vboard/showthread.php?t=572174)

ChevyC102007 03-24-2013 02:12 AM

Distributor/Timing Problems
 
Ok well I figured after 30 years the original HEI in my 1980 Chevy was due for an overhaul/replacement. So I purchased a Mallory unit to replace it, after installing it I noticed that it didn't seem to be working correctly (Id move the distributor towards the firewall and it retarded the timing instead of advancing it, moving back towards the carb it would advance it :confused:).

After looking at the product info online and talking with my "tech support" AKA my dad, i did some more digging, not only was the balancer timing mark off (due to a bad balancer) but the timing chain itself was worn.

Replaced timing chain with a double roller from Cloyes with 4 key ways, I installed it "straight up" according to the diagram, replaced the balancer and finished buttoning it all back up.

Now back to the distributor got it put in and truck seemed to be running fine, that was about 4 months ago. Now when I accelerate I can hear it popping back through the carb (EDL-1406) and I have no power, Ive tried to set the timing but the aforementioned advance/retard confussion makes it hard to do.

I installed the chain as directed, I rechecked the dizzy to make sure I got it in on No.1, everything checks out. Ive put in Cloyes double chains before with no problems.

Which brings me to the question.

Does anyone have any experience with CFR Performance distributors? Are they worth the $70.00 price tag from Amazon or am I better off switching the Mallory to a MSD Street Fire?

Sorry so long just wanted to try and make sure I explained the problem as best as I could. Just wanna be able to drive it to and from work.

Dead Parrot 03-24-2013 08:07 AM

Re: Distributor/Timing Problems
 
One thing to check are the step up pistons in the carb. They can gum up and start sticking. If they stick in the down position, it can cause a lean mixture on acceleration. To clean, loosen the piston covers and pivot to the side. Then use a lot of carb cleaner on the pistons, cylinders and metering rods. Make sure none of the small springs escape. When clean, reinstall the pistons and rods back into the cylinders, making sure the rod tips are in the jets. Don't over tighten the piston covers.

bilfman 03-24-2013 10:55 AM

Re: Distributor/Timing Problems
 
It does sound like a timing issue. Put your no.1 cylinder at tdc on the compression stroke, remove your distrubutor cap and make sure the rotor is pointing to where you have the no.1 plug wire.

That will at least eliminate 1 possible issue. If it is not pointing to no.1 there are 2 things that you can do, lift the dizzy out and try to cog it so it points there or you can move all plug wires forward/backward depending on which way you need to go. Also ensure firing order is correct 1-8-4-3-6-5-7-2.

Not sure if you have a timing light, but if you don't a hillbilly timing method to get you going until you do is. Once running get 2 people, one in the cab, one at the dizzy. Start is up and do mild brake torque ( in gear, little brake, little gas) basically load up the engine in gear without the truck moving. Other person then turns the dizzy to the sweet spot that makes the most power.

This entire proceedure is between 15-20 mins and costs nothing, good place to start.

silversnail86 03-24-2013 01:31 PM

Re: Distributor/Timing Problems
 
First off, looking straight down at the distributor clockwise=retard/ counter clockwise=advanced. Now, assuming you haven't been tinkering with it, and this was an all of a sudden type of problem. I would start by looking for cooked plug wires at the exhaust, then check for broken plug and power/ground wires to the distributor, then pop the cap and look it over for cracks ( it is common for a distributor to whack the firewall if you have worn or broken motor mounts), next I would remove the rotor and look for broken or frayed wires there, the module could be toast as well, parts store should be able to check the module though. Next I would buy a timing light. cheaper and better money spent than on a new distributor. You can replace all the parts inside that HEI. I would never use the aforementioned "hillbilly" way to set the timing, when you put the engine under load the vacuum advance comes into play, which is not adjusted by turning the distributor.

Read this over and over til you understand how it works!!
http://www.73-87.com/7387garage/drivetrain/hei.htm

Now if you had pulled the distributor,or adjusted it, before the popping started I'd say the timing light will work wonders.

ChevyC102007 03-24-2013 05:03 PM

Re: Distributor/Timing Problems
 
Checked, rechecked and triple checked wires, rotor and cap didn't find any cracks or burn marks. Read and reread my engine manual, studied firing order and directional diagrams, read online manuals and product literature to make sure I didnt miss something. I even took it down to the weights to check the wires to the module and the weight springs. Only thing I havent done is to adjust the vaccum advance since the Mallory has that option.

Unless my timing light is off I have the engine timed at 10 degrees BTDC, which the engine was happy at with the old Dizzy that I replaced with the Mallory unit. I guess I will quadruple check these things and clean the carb step up pistons.

But if all this checks out that still begs the question that I asked....................Does or has anyone dealt with CFR Performance Distributors? Are they worth it or not?

ChevyC102007 07-21-2013 12:06 AM

Re: Distributor/Timing Problems
 
I went ahead and bought the CFR Distributor, haven't gotten around to putting it in yet.

After I installed the Mallory unit the truck ran fine for about a month or so then this mess started. I have replaced the wires/plugs and found no burnt boots.

Hopefully will get the CFR put into the truck tomorrow and check a few of the vaccum lines while Im at it to make sure I aint got a vaccum leak somewhere.

ChevyC102007 08-24-2013 11:14 AM

Re: Distributor/Timing Problems
 
Well put in the new CFR distributor. Made sure of my firing order and the ole fellar runs like a new one. Surges abit at idle but Im sure that's a vaccum leak somewhere or the fuel pumps going bad. However I did have to time the engine by ear as my balancer is shot (again) so accurate timing with the light isn't possible. Thanks for all the help.


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