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My Dodge is slowly dying ..........
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Author:  barebones [ Mon Apr 02, 2018 7:38 pm ]
Post subject:  My Dodge is slowly dying ..........

I have a 1985 W100 225 Manual.

I bought it in 2000. It appears someone had done an engine swap with an older (1980?) motor. The ESA was still functioning but the carb was older - a Holley 1945 #2839.

In 2006?, I rebuilt the motor(stock), and I replaced the fixed ESA distributor w/mopar electric ignition, and I bought a rebuilt carb - a Holley 1945 #8831. It worked only OK for a couple of years, but more and more, the engine is lacking in both power and acceleration. Performance is the same hot or cold. sometimes it runs fair on hills, usually not.

Here's what I've done:
* Exhaust OK -Custom, oversize pipe, long cherry-bomb muffler, Four bends, 2-90, 2-120.
* Checked Electric fuel pump 1 1/2q in 1 min. Maintains 5lbs pressure (spec). Gas line replaced. Goldenrod filter before pump; spec filter after.
* Compression Avg 117lbs all within 10%.
* Checked intake manifold for leaks hot and cold. Used propane around intakes at head and carb to test.
* Checked timing 14d @ 710rpm w/o vacuum. With vacuum ~38d at idle.
* Checked Vacuum. 18-19 at idle (@4000ft) Tromp accel pedal 2 to 18-19in. Rings OK?
At 60-65, I have about 4-5in vacuum. Rings not OK? Hard to find a level stretch!
Some occasional vacuum flutter of a pound or 2 - probably ignition?
* Cam timing? I don't have the specs.

I'm down to two possibilities:
* Mopar ignition weak. I'm using E3 plugs that seem to be working great so far.
* Holley 1945. Power valve or Accelerator Pump ... or both.

ANY HELP OR SUGGESTIONS APPRECIATED!

These Holleys! 1945's have more variations than the number of people in China!
I just picked one up - rebuilt and never installed for cheap, cheap, cheap. It's a 1945 #9342. The Power Valve vacuum piston appears to have an external connection to the manifold vacuum back through the carb and internally to the throttle housing! Isn't restricted to 55deg throttle opening. It's sensitive to any drop in vacuum.

How can I get the specs for the 1945'?

Author:  SlantSixDan [ Mon Apr 02, 2018 8:17 pm ]
Post subject:  Re: My Dodge is slowly dying ..........

Welcome here.

Those "E3" things are sparkplug-shaped trinkets. You don't specify how it is that you think they work great (given that your vehicle isn't running well), but marketing psychology is a probable cause. Get 'em out of there and put in real spark plugs. NGKs are good. Tune-up parts and technique suggestions in this post.

The Mopar ignition system is not the strongest system on the road; consider the HEI upgrade, but no, the Mopar system is not inherently weak. If the Mopar kit you installed was the Mopar Performance kit with the new distributor and the orange control box, that's a system with advance curves that won't give good running results except in a drag race car.

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.

Author:  Jase [ Tue Apr 03, 2018 2:16 pm ]
Post subject:  Re: My Dodge is slowly dying ..........

Rings are probably ok, as you have consistent compression readings.. it may be wise to assume the long block is sound, for the present moment and focus on the basics of air-spark-fuel....

As Dan suggested, check the ignition system for a high quality strong spark. Scrutinize the carb.... if the motor has never run well since the electronic ignition was installed, check for proper ignition timing... and maybe timing chain slack..

Author:  Rick Covalt [ Wed Apr 04, 2018 3:18 am ]
Post subject:  Re: My Dodge is slowly dying ..........

What is the total timing? W/O vacuum?

Author:  SpaceFrank [ Wed Apr 04, 2018 5:31 am ]
Post subject:  Re: My Dodge is slowly dying ..........

Quote:
* Checked timing 14d @ 710rpm w/o vacuum. With vacuum ~38d at idle.
That sounds like way too much advance at idle with vacuum. Do you have the vacuum advance hooked up to manifold vacuum? It should be seeing ported vacuum. If it runs rough going up hills, you might be pinging with that much advance.
Quote:
* Checked Vacuum. 18-19 at idle (@4000ft) Tromp accel pedal 2 to 18-19in.
I'm not sure what you mean here. Does it drop from 18-19 down to 2 when you stomp on the pedal?
Quote:
At 60-65, I have about 4-5in vacuum. Rings not OK? Hard to find a level stretch!
That doesn't sound like very much vacuum at cruise, but I wouldn't suspect rings given your good compression test results. Have you checked your hot valve lash recently?

Author:  Rick Covalt [ Wed Apr 04, 2018 2:34 pm ]
Post subject:  Re: My Dodge is slowly dying ..........

14 at idle may be too much advance when all the mechanical advance kicks in? What do you see when you hook up your light and rev it up o @ 3000 RPM?

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