Big Block Engine Forum - Grinding on shut down...

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Grinding on shut down...

Printed From: The Ford Torino Page
Category: Powertrain Specific Forum
Forum Name: Big Block Engine Forum
Forum Description: 429 and 460 engines
URL: https://forum.grantorinosport.org/forum_posts.asp?TID=9550
Printed Date: 26-March-2026 at 5:08PM
Software Version: Web Wiz Forums 12.06 - https://www.webwizforums.com

Topic: Grinding on shut down...

Posted By: 72BoB
Subject: Grinding on shut down...
Date Posted: 31-July-2013 at 6:01AM

I am in the middle of troubleshooting several issues I'm having with my engine right now and I think that I at least have good ideas on where to start checking for my first two issues: car dying as soon as it's put in gear, and dieseling; however I cannot find anything regarding my third issue.

Occasionally when I shut the engine off and it diesels for a couple seconds I will hear a loud grinding and clunk followed by a gray mist or spewing gas out of the carburetor vent tubes, almost like the engine briefly started pushing backwards. I know this sounds just like dieseling, but I cannot figure out what the grinding is.

I am running a Summit mini-starter and it is currently wired through both the starter solenoid on my inner fender, and the built in solenoid on the starter itself. I have put maybe 500 miles on the engine but this hasn't been occurring until these past few weeks. I am about to pull the starter and check the flywheel, but I had my transmission rebuilt this past weekend and they inspected them for me and they said they didn't see any excessive markings on either. I have been doing quite a bit of work on the engine these first few days this week with quite a bit of starting and stopping followed by dieseling and grinding so I will at least pull the starter to check again.

So, whatcha thinking?

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1972 Torino

Replies:

Posted By: Regul8r
Date Posted: 31-July-2013 at 7:04AM

As for the obvious, yes it does sound like dieseling.

That means the timing is way off and she is getting hot.

Don't worry about getting hot yet, first set the timing properly and check all the timing items.

1. Check the base timing at idle without the vacuum advance hooked up

2. Rev the motor and check the mechanical advance is adjusting the timing properly and also that it comes back to base when you let off the revving

with both base and mechanical checked, adjusted and verified...

3. Ensure the Vacuum advance line is hooked to a properly metered vacuum port and not direct vacuum all the time.

4. with the motor up around 2k there should be vacuum at the line, the mechanical should have the advance to the max, now hook the vacuum and watch the advance go up even more.

That should get you where you need to be.

Once that is all done and proper then you can go digging for the other issues.

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Carl Corey (Moderator/Event Coordinator) Contact ANYTIME!
1976 Ford Elite "Lola Mae"
97 Suzuki Intruder 1400
US Army Retired

Posted By: 72BoB
Date Posted: 31-July-2013 at 7:55AM

Wow... sure enough, I should never trust any mechanic. When they rebuilt my transmission they said they adjusted the timing to make it easier to start. When I picked the car up from the shop it definitely was not easy to start, and I've had issues with it this entire week.

So, being dumb, I trusted the mechanic and never really fully checked the timing and therefore overlooked it when trying to figure out my issues. Sure enough, when I finally check the timing, the guys at the shop had it set to over 30 degrees advanced initial. I thought it was a mistake so I checked, and rechecked, and sure enough it was over 30 degreed advanced (my integrated balancer/pulley timing marks stop at 30 degrees). I turn it down to around 12-14 degrees and it seems to have fixed, well, everything.

I might have been assuming I had those three separate issues were in fact, separate, when in the end it all seems to come back to the way, way advanced timing.

Moral of the story: Don't trust your mechanic and if you do, at least double check even the basics when something goes wrong...

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1972 Torino

Posted By: Regul8r
Date Posted: 31-July-2013 at 10:05AM

Good catch!

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Carl Corey (Moderator/Event Coordinator) Contact ANYTIME!
1976 Ford Elite "Lola Mae"
97 Suzuki Intruder 1400
US Army Retired

Posted By: 72BoB
Date Posted: 07-August-2013 at 2:23AM

So, the problem isn't entirely fixed...

I am currently running a Summit mini-starter http://www.summitracing.com/parts/sum-820048-m/overview/" rel="nofollow - http://www.summitracing.com/parts/sum-820048-m/overview/ .

The starter is wired through both the fender starter solenoid, AND the built in solenoid. Could this be a possible cause of the grinding sound as if for some reason current might be passing through and reengaging the starter?

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1972 Torino

Posted By: Regul8r
Date Posted: 07-August-2013 at 5:13AM

it has a relay ON the starter?

Does the starter have a battery positive feed large post and the relay has a ignition/start wire feed small post

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Carl Corey (Moderator/Event Coordinator) Contact ANYTIME!
1976 Ford Elite "Lola Mae"
97 Suzuki Intruder 1400
US Army Retired