351C Distributor Issues - What best to do

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Author Topic: 351C Distributor Issues - What best to do  (Read 3173 times)

Offline Glen Mach 1

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351C Distributor Issues - What best to do
« on: December 21, 2021, 04:28:09 pm »
Hi all,

My car has been cutting out when driving when getting warm so I suspected an electrical problem, all the earths are good so leads me to think it is the distributor.  The warmer the engine gets the more the engine seems to get out of timing and miss and drop out.  Has anyone experienced this before?

I have a Mallory Comp 9000 Unilite Breakless Ignition distributor which I suspect is 15 years old with a Mallory Promaster Coil electric ignition.

Should I get the distributor looked at for repair or buy a new one?  What would be the best comparable distributor to use if I was to replace.

Thanks in advance for any advice.

Glen
Cheers Glen

Offline FB.65.68.70

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Re: 351C Distributor Issues - What best to do
« Reply #1 on: December 21, 2021, 05:33:29 pm »
Hi Glen,
have you checked your spark plug wires yet ?  Ive had a set that got old and developed a higher resistance , engine misfired when it got warm.
Heres a link to see how to check , if you need it .
https://www.instructables.com/How-to-Test-a-Spark-Plug-Wire/#:~:text=%20How%20to%20Test%20a%20Spark%20Plug%20Wire,were%20replaced%20about%205000%20kilometres%20ago.%20More%20

Good luck with your problem.

Offline barnett468

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Re: 351C Distributor Issues - What best to do
« Reply #2 on: December 22, 2021, 03:44:11 pm »
The warmer the engine gets the more the engine seems to get out of timing...

Have you actually checked the timing with it hot and cold?

Misfire when hot is also sometimes caused by the coil.

Offline Glen Mach 1

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Re: 351C Distributor Issues - What best to do
« Reply #3 on: December 23, 2021, 08:41:13 am »
Yes you can tell the engine runs more rough the longer it goes and the hotter it gets.  When I looked at other blogs it seems to be a common issue with the coil.  Where would be good to go in Brisbane to get this looked at? Or do you just replace the coil?  The distributor is over 15 years old so not sure if the papers will be available?
Cheers Glen

Offline seany-boy

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Re: 351C Distributor Issues - What best to do
« Reply #4 on: December 25, 2021, 08:28:50 pm »
is your coil attached to the engine? I had exactly this issue with my original oil filled coil, just another thing to consider- might be an easy swap for a day or 2.

Offline Fitzy1980

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Re: 351C Distributor Issues - What best to do
« Reply #5 on: January 06, 2022, 11:01:27 pm »
When you say "gets warm" do you mean like on fire??

 :bolt:

Offline Glen Mach 1

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Re: 351C Distributor Issues - What best to do
« Reply #6 on: January 08, 2022, 11:12:58 am »
No just up to a normal running temperature, not overheating.
Cheers Glen

Offline Glen Mach 1

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Re: 351C Distributor Issues - What best to do
« Reply #7 on: January 14, 2022, 10:47:22 am »
Does anyone have a Mallory HyFire® Electronic Ignition Control or similar?  What is the benefit of having one, better cold start and idle when cold?

Also the previous problem was not the coil but the distributor I needed a Mallory 605 Unilite Ignition Module; Thermaclad replacement part, which is on order.

Thanks

Glen
Cheers Glen

Offline Glen Mach 1

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Re: 351C Distributor Issues - What best to do
« Reply #8 on: January 21, 2022, 09:29:43 am »
Hi all,

The replacement Mallory 605 Unilite Ignition Module for the dizzy did the trick.  All back together and not cutting out when hot just playing with the timing now.  From what I can read for a 351C about 15 degrees BDTC at idle 900rpm and 35 degrees at 2500 rpm.

Thanks

Glen
Cheers Glen