Engine hesitation (1 Viewer)

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Ok...got it buttoned up.

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Was super nervous it wouldn't start...and initially didn't because timing was off. Got it started, but have the same issues as before...it idles great. Step on the gas and get hesitation then about 2-2500 rpm it sounds like it is missing every couple seconds. I put the original '80 carb back on and know for sure I don't have it correctly. At 7btdc I can get about 18 units on the vacuum guage. If I adjust the timing to about 11btdc (by turning ccw), I can get about 20 units on the vacuum guage. The 11btdc setting makes it run a little better, but still not right. I am pretty sure I don't have the carb/timing set up correctly. Small victory...it does not overheat and the head gasket replacement worked.

@FJ40Jim can you help by looking at the carb picture to see what I am messing up?
The hose from the valve cover side of the carb goes to the dizzy advance.
I know I have to cap some of the ports, etc...just not sure which ones to cap.
The 2 hoses on the front of the carb were hooked like that when I got the vehicle (so highly likely the PO did it wrong).
There is one hose at the base of the carb that is shaped like a U...is that right?
With the idle speed screw, I can not get the rpm lower than about 850.


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I'm pretty sure I have a vacuum retard dizzy so I removed the line to that per Jim's instructions earlier in this thread. And capped the other ports on the carb. No change...it idles great, but I can’t get about about 1500 rpm without it wanting to crap out. If I try to add throttle quickly, it sucks air and almost dies. Timing is about 10-11btdc and vacuum is 18ish then after adding some throttle goes to 20ish.
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middlecalf

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Wish you’d hurry up and get this figured out so then I can follow your lead and get mine figured out 😝. (My setup is a bit different but similar symptoms)

I would think when you give a little throttle that the vacuum would drop a lot, to single digits, or are you talking about adding more idle? Are you measuring vacuum off the manifold somewhere?
 
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@middlecalf - it's so frustrating being so close. I feel like there is something simple at this point. When I add throttle, vacuum goes to about 10. Measuring it from the brake booster manifold connection.

Here is a video of what it's doing:
 
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So, today I put the old coil back on and it started quickly, but ran the same...idles great but at roughly 13-1500 rpm it would stutter hesitate and I can't get above that rpm. It was like the spark was not strong enough. Then the truck just died like I turned the key off...just like it did back in the first couple threads when the Pertronix unit died. Then, no spark. Second Pertronix dead after I did the "bench test". Called Pertronix and they have crappy customer service and basically say their units don't fail. The dude told me to send in the unit and they will test it...then he will decide if they are going to send me another unit, or refund me, etc. He said he was doing me a favor by testing the unit to let me know what is causing their units to go dead since they never go dead. So...I have to send in the unit, then wait for them to test it and get back to me.

In the meantime, I changed the original Toyota carb to the City Racer carb and switch back to the points to test to see if that changes anything. I have never installed points, so should be interesting. I also am going to put a new dist condenser on and spark plug wires (it's hard to find spark plug wires and the condenser...have to order those too.)
 
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Did you connect that brake booster hose to the intake manifold?
Originally...or at some point today? I'm using that intake manifold port with the vacuum gauge, but am using the intake manifold port that was on the vehicle when I got it. The brake booster hose was connected to that port. Here is a picture:

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FJ40Jim

The Cruiser Whisperer
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I'm pretty sure I have a vacuum retard dizzy so I removed the line to that per Jim's instructions earlier in this thread. And capped the other ports on the carb. No change...it idles great, but I can’t get about about 1500 rpm without it wanting to crap out. If I try to add throttle quickly, it sucks air and almost dies. Timing is about 10-11btdc and vacuum is 18ish then after adding some throttle goes to 20ish.
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On the top front of the carb are 3 vac fittings, the center one goes to choke breaker (as pictured). The other 2 should be capped off.
The loop of hose under carb is OK.
The only fitting needed on the valve cover side of carb is the forwardmost, which is ported vacuum for a vacuum advance dissy ( if equipped).
 
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On the top front of the carb are 3 vac fittings, the center one goes to choke breaker (as pictured). The other 2 should be capped off.
The loop of hose under carb is OK.
The only fitting needed on the valve cover side of carb is the forwardmost, which is ported vacuum for a vacuum advance dissy ( if equipped).
Thanks @FJ40Jim . I am pretty sure earlier in the thread you told me mine was a retard dizzy, so I have the valve cover carb ports capped off also.
 
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Here is the update...I got it running...and driving. I have to say...I have learned so much on this thing. Rookie move...I didn't take pictures when I pulled the points thinking I was going to be Pertronix...don't need the points, right? Well, that little rubic's cube (distributor rebuild) took a bit to get correct...not a lot of good detailed pictures on the web of the inside of the dizzy. Pics attached for anybody putting points back in. I sent the second Pertronix unit back to them...waiting to see why I had 2 units fail. Has anybody heard of that?

After I got the points back in (point gap set at .018), new spark plug wires, the City Racer carb on, it fired up. I do think my stock carb will work also, but going to run the City Racer one for a while. Timing is set to the BB and the carb mixture and idle set. Took it for a 20 min test drive...then later about 30 min and runs great (and the temp gauge stays on the first temperature barb). I suspect I will have to adjust the valves soon as well as oil/coolant change to ensure I'm running with clean fluids, etc.

What was happening...I think the Pertronix spark wasn't doing it...it was yellowish white at the spark plug. (As a reminder, I have the Flame Thrower coil too...I have that one installed right now). When I added throttle, I think the spark wasn't hot enough to fire correctly and the engine sounded like it was getting extinguished.

A huge thank you to everybody on here...@Dizzy, @FJ40Jim, @rsnellie and everybody else. @rsnellie...thank you.

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