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Author Topic: Need Engine Help Low Vacuum Reading  (Read 7857 times)

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Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #15 on: March 29, 2015, 09:02:12 PM »
[size=12]It's hard to see in this picture but the  two arrows show how the water is flowing.  Is this normal or did I find the LEAK?
[/size]

Offline 1955CJ-5

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Re: Need Engine Help Low Vacuum Reading
« Reply #16 on: March 29, 2015, 09:35:44 PM »
I think you have a leak..the only way water would flow out of the intake tubes is if you poured it in through the carb flange....that chamber is for hot exhaust gasses to warm the intake tube, but not flow through it....

Try a flashlight in a dark room shined into the tubes...you ought to be able to see it...
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Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #17 on: March 29, 2015, 09:53:05 PM »
[size=12]I tried flashlights and tiny mirrors but could not confirm a leak.� The water flowing in the exhaust and out the intake did it for me.

You have no idea what finding this did for me. I'm embarrassed by how much time I spent chasing this!!!�
[/size]
« Last Edit: March 29, 2015, 09:53:31 PM by CJPilot »

Offline 1955CJ-5

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Re: Need Engine Help Low Vacuum Reading
« Reply #18 on: March 29, 2015, 09:58:03 PM »
Don't be embarrassed.....intakes are known to crack but your's is unusual for sure.....Glad you found it, nice work...

 
1955 CJ-5, A friend for 58 years....1951 CJ-3A, a new addition. 1929 Model A Ford Closed Cab Pickup...

Offline scoutpilot

Re: Need Engine Help Low Vacuum Reading
« Reply #19 on: March 30, 2015, 05:06:40 AM »
[size=12]The simple fact that you had the intuition to look where you did bodes well for you. Now the search for another intake begins as I don't think the one in hand is salvageable.[/size][/b]
Old fashioned service never goes out of style.
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Offline Ryan_289

Re: Need Engine Help Low Vacuum Reading
« Reply #20 on: March 30, 2015, 10:04:09 AM »
I may have a good intake at the shop.  If I remember correctly it had some broken bolts in it and would need machined on the mating surface.  If I still have it your welcome to it. 

Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #21 on: March 30, 2015, 07:14:44 PM »
Ryan thank you for your generous offer. I think I may have an intake on a parts jeep.

After watching me find this leak my significant other thinks I should buy a new intake manifold.   :o

Offline scoutpilot

Re: Need Engine Help Low Vacuum Reading
« Reply #22 on: March 31, 2015, 06:05:17 AM »
[size=12]Hmmmm. An understanding AND generous significant other. There's a rare find.[/size][/b]
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Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #23 on: April 05, 2015, 08:14:17 PM »
[size=12]I installed the new intake after machining the block interface flat and the opening up the area for the PCV. The engine finally runs half way decent.

My next issue, small as it may be, is something I think should be resolved. The engine idles at 980 rpm, not the 600+ rpm it is suppose to.  It idles fine just too fast.  I have backed the idle set screw out all the way.  I have adjusted the ignition timing with a timing light.   I ran it with the accelerator linkage disconnected and the PVC valve port blocked.  I sprayed the intake manifold down with stating fluid and no found no leaks. The vacuum is mostly steady at 19.  The idle mixture screw is out 4 turns. If I turn in the idle mixture screw in the engine starts to stumble and run rough.  I feel I have another small vacuum leak but it�s not showing up by spraying the intake with starting fluid.   If you have any ideas were I should look please let me know.
[/size]



Offline scoutpilot

Re: Need Engine Help Low Vacuum Reading
« Reply #24 on: April 06, 2015, 05:11:58 AM »
[size=12]The metering rod in the carb may be too high.[/size][/b]
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Offline Ryan_M

Re: Need Engine Help Low Vacuum Reading
« Reply #25 on: April 06, 2015, 06:31:59 AM »
I had the same problem as what you are describing. With the help of roughly 1000 patient e-mails and this excellent video Scoutpilot got me back on track.

[media]https://www.youtube.com/watch?v=jcjB0iGEEmQ[/media]
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Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #26 on: April 06, 2015, 08:43:40 PM »
Thank you Scoutpilot and Ryan.  Once I get a little shop time I'll check that out.


Offline CJPilot

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Re: Need Engine Help Low Vacuum Reading
« Reply #27 on: April 10, 2015, 10:09:13 AM »
[size=12]Throttle connector rod seems good, it's not binding at all at the pump arm.

Does the metering rod setting effect the idle that much? I always thought it set up the mid range fuel delivery.[/size]

Offline athawk11

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Re: Need Engine Help Low Vacuum Reading
« Reply #28 on: April 10, 2015, 10:45:39 PM »
The metering rod does affect the idle.  Mine was set too high off the seat.  Before I fixed it,  I had to turn up the idle  to a 1000 + just to keep the engine running.  The carb would also drip fuel out the throttle shaft after shut down.  Once the rod was properly adjusted, both issues went away.  I have my idle at 700.  I like the way my engine sounds and responds with this setting.

Tim
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