318 Idle issues

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May be correct about the Avenger line but the post screenshot only proves the guy didn't know what he was doing and blamed the carb. Changing jets for an idle problem is silly, and that's being charitible.
Exactly. Just like guys saying a blown power valve is responsible for a rich idle. Wrong answer.
 
Exactly. Just like guys saying a blown power valve is responsible for a rich idle. Wrong answer.
Unless its leaking through to the vacuum passage, when then it can. But honestly had poor sealing with the PV gasket speraerating in the middle far more than I've had PVs with a diagphram that was torn.
 
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Unless its leaking through to the vacuum package, when then it can. But honestly had poor sealing with the PV gasket speraerating in the middle far more than I've had PVs with a diagphram that was torn.
I've never seen one torn, but I have removed one to prove the point that they have zero effect at idle. I did it for a hard headed Chevy guy that just didn't know when to shut up.
 
I feel for you, 67Dart440GT. I went through similar issues with my 340. Turns out that there were 3 intake and 5 exhaust valves with small leaks due to a poor valve job. Compression testing wasn't precise enough to catch this. When I did a leakdown test, I found the issue.
The one thing in all these posts that strikes me as relevent is the fact that you can close off the choke and the engine will still idle fine. That is the anthesis of what the choke should be doing. It should kill the engine immediately when closed unless there is another source of air to keep the engine running.
 
My question is was it running like this before you pulled the engine to fix the oil leaks or did it stat running bad after the engine was reinstalled? Just trying not to overthink it.
 
My question is was it running like this before you pulled the engine to fix the oil leaks or did it stat running bad after the engine was reinstalled? Just trying not to overthink it.
The vacuum was always an issue as far as somewhat low, and erratic. When I first got the car the idle was set at like 1100rpm. I only drove the car 2 or 3 times last year.... so to be honest I really didn't take any notice of it then.
 
The vacuum was always an issue as far as somewhat low, and erratic. When I first got the car the idle was set at like 1100rpm. I only drove the car 2 or 3 times last year.... so to be honest I really didn't take any notice of it then.

My thoughts as the they kept the high idle to keep it running smooth. Does the problem get be better just off idle? Meaning, does it smooth out if you raise it off idle?
 
Ok i read all 4 pages and im nowhere nears as qualified as most guys posting.
Question standard or power brakes?
 
We've found some issues. I'll let Colin update when he gets a minute.
 
Yay

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Pretty amazing the engine only has 2500 miles on it! It's almost like I was lied to.
Either that or someone did a really crappy "rebuild". I'm awful sorry man. It just keeps getting worse and worse. BUT, like I told you earlier today, every system you've touched, you have repaired. So that's a good thing!
 
Either that or someone did a really crappy "rebuild". I'm awful sorry man. It just keeps getting worse and worse. BUT, like I told you earlier today, every system you've touched, you have repaired. So that's a good thing!
I certainly appreciate all of the help you and everyone else has given me.
 
If you can cover the primary bores and/or close the choke with no/little effect then it’s running on air from somewhere. Either the secondaries are open or it has a vacuum leak. Period. Pull carb off, turn it upside down and close the secondaries down tight, but not sticking. Then re tune the primaries.
Out of all the advice I see on here, It has to be getting air from somewhere I would address this issue first.
 
I pulled two plugs tonight to do a compression test. Both plugs looked extremely clean. Light brown I'd say. I got tired at the end of the night but number 1 and 2 are at 145 psi. I will do the rest this weekend.

I don't know what IFR and IAB is.

Thanks.
I always pull all the plugs when doing a compression test. Maybe I missed it, but did you cap off the distributer vac line while looking for a leak. I hidden leak can be in the distributer diaphragm, same as in a brake booster.
 
One possibility I haven't seen mentioned is whether the carb base might be warped. That will for sure cause a vacuum leak. Possible causes include overtightening the carb to the intake (100 inch pounds max), especially with a thick gasket.
 
One possibility I haven't seen mentioned is whether the carb base might be warped. That will for sure cause a vacuum leak. Possible causes include overtightening the carb to the intake (100 inch pounds max), especially with a thick gasket.
I checked the carb with a straight edge. Everything appeared to be normal. I'm going to have more time to look into everything this week. I'm probably going to tear the carb apart and rebuild it.
 
I always pull all the plugs when doing a compression test. Maybe I missed it, but did you cap off the distributer vac line while looking for a leak. I hidden leak can be in the distributer diaphragm, same as in a brake booster.
I took every vacuum system off the carb and plugged them to eliminate all of those variables. I found no change.
 
I took every vacuum system off the carb and plugged them to eliminate all of those variables. I found no change.
The brake booster vac line does not go the carb but to the intake. There are other vac lines that go to the ac switch, if you have ac. I use WD40 to look for leaks around the carb base, intake to heads and other vac locations. Be careful using a highly flammable product for that purpose. Being one bank is all low on compression, I think you may have a head or valve issue not a head gasket issue.
 
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