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Discussion Starter #1
I have a 1976 Winnebago Minnie Winnie on a Dodge chassis (b300 I believe) with a 360 motor. I have been replacing things lately with not a lot of luck. I have replaced the fuel pump, fuel filter, some sections of fuel line (disconnected rear tank and ran fuel line directly to front tank) new alternator, rebuilt the carb (holley 2245), and replaced spark plugs.

I have also rewired the ignition system to clear up some electrical issues and I have started plugging some vacuum lines that appear to go nowhere. (some went to cruise control that is no longer in use) I also disconnected the charcoal cannister as it was feeding charcoal into my carb.

I believe the spark plug wires and cap and coil were replaced shortly before I bought it as well.

I have gone through and I think I have my carb set right and have my timing correct as well.

Finally the issue: I can get the motor to start up and idle fine every time, however as soon as I place it into gear it dies almost instantly especially if the idle is low. I am able to drive it as long as the idle is very high but coming to complete stops is not really an option at that point. I am looking for suggestions on what could be my issue here and possible remedies to fix it.

I would also like to remove a lot of the unnecessary emissions stuff on this thing. There are vacuum hoses running everywhere and the less hoses I have the less leaks I could have. Emissions are not an issue here and this will only be driven once in a blue moon anyhow.

Any help is appreciated.
 

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Does it idle smooth, or rough ish, orrrrrrrrr?

Does initial timing change when you put it in gear?; or apply the brakes?

... Sounds hard to start, and idle sounds inconsistent, correct?; if so, any ideas why? (guessing vac advance and/or it's vac source could cause both stalling and start/idle issues; or carb issues too).

... Would check again for vac leaks. ... EGR issue?
 

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Sounds like a timing issue to me. Like key99 said, check that the vacuum advance is connected and not leaking.

How did you set the timing? Disconnect the vacuum advance and plug the line before shooting with a timing light. I usually set timing with a vacuum gauge instead of a light trying to obtain the highest vacuum reading on the gauge. Make sure you aren't idling too high when you set timing too. Some distributors will start to give mechanical advance as early as 800 RPM.

If you are sure the timing is correct then again, as key99 said, check for vacuum leaks. You can use either a can of carb cleaner or propane/MAPP gas and spray all along every vacuum line and the carb and intake gaskets.

There shouldn't be too much emissions stuff on a '76. Maybe lean burn carb and EGR. When you replaced the carb did you put a lean burn on? If you did, that could be a source of your problems. Speaking of EGR, I hear that that is often a source of vacuum leaks. I don't know a whole lot about that though since that is usually one of the first pieces I yank off of older vehicles.
 

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rebuilt the carb (holley 2245)
I think I have my carb set right
How did you go about this? Did you adjust the mixture screws for max vacuum? Another trick is to do this when in drive(e-brake on chocked of course). Set the idle speed so it wont stall then adjust the mixture screws for the highest smooth rpm then drop down the idle speed. This is the poor mans way(someone without a vac gauge) and works very well. :)
 

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Discussion Starter #5
As far as the idle goes it isn't perfect, it's a bit rough.

Sounds like a timing issue to me. Like key99 said, check that the vacuum advance is connected and not leaking.

How did you set the timing? Disconnect the vacuum advance and plug the line before shooting with a timing light. I usually set timing with a vacuum gauge instead of a light trying to obtain the highest vacuum reading on the gauge. Make sure you aren't idling too high when you set timing too. Some distributors will start to give mechanical advance as early as 800 RPM.

If you are sure the timing is correct then again, as key99 said, check for vacuum leaks. You can use either a can of carb cleaner or propane/MAPP gas and spray all along every vacuum line and the carb and intake gaskets.

There shouldn't be too much emissions stuff on a '76. Maybe lean burn carb and EGR. When you replaced the carb did you put a lean burn on? If you did, that could be a source of your problems. Speaking of EGR, I hear that that is often a source of vacuum leaks. I don't know a whole lot about that though since that is usually one of the first pieces I yank off of older vehicles.
I will try timing it again with a vacuum gauge instead. I used a light previously as I've never done it with a gauge. Using the light was very difficult however as I could barely see the marks and it became more of a two man job with half the motor being in the cab and half in the front.

I have tried spraying carb cleaner around some of the vacuum hoses but nothing seems to change when I do which either means no leak or a really major leak somewhere else. I've also sprayed it around the carb also and didn't notice any changes.

And as far as the emissions stuff goes most people tell me all you really need is your PCV hooked up, your brakes hooked up, your advance, and not much else. This thing has hoses going everywhere but I have about half of them plugged now.

Any other advice would be appreciated. Thanks!
 

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As far as the idle goes it isn't perfect, it's a bit rough.

I will try timing it again with a vacuum gauge instead.

I have tried spraying carb cleaner around some of the vacuum hoses
I've also sprayed it around the carb also

And as far as the emissions stuff goes most people tell me all you really need is your PCV hooked up, your brakes hooked up, your advance, and not much else. This thing has hoses going everywhere but I have about half of them plugged now.
... Hopefully idle issues are something simple (plugs or wires etc); address this to rule out:---
--- leaking intake valve/s; which can upset vac signals to carb messing up the fuel metering for the next cyl/s; vac gauge helps here, watch for a needle that flicks/"drops" a bit (needle drops a couple? inches HG when cyl with bad intake valve fires, and leaks positive pressure into negative pressure manifold)
--- a bad "flat" camshaft lobe and lifter (its "flat" type cam lobes and lifters need zinc type oils to survive; zinc/ZDDP has been increasingly taken out of many engine oils for almost 3 decades)
---cyl compression issues

... Or could be leaking intake gaskets, which can also upset carbs fuel metering at idle (as txwooley said, check/spray intake gaskets between intake and heads).
... IMO, good idea to snug/check intake bolts; follow the torque sequence.
Go gently at first in case some are weak/rusted etc; if they feel good torque them (if any feel bad, stop, to avoid breaking bolts)

... "Emmisions stuff": basic list sounds good, but IDK squat about carb deletes/purges/vents etc.

... EGR valve can be a major leak and cause irregular idle issues; could check/spray it; or better yet block it off, forever!

... Helpful to mention if vac advance is hooked to manifold vacuum, or ported.
 

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Discussion Starter #7
Okay.. I messed around with it a little again today..

1. I bought new plugs wires, cap and a rotor but haven't put them on yet but will soon. I hope this helps it a little bit anyways.

2. I attached a vacuum gauge today and ran it for a while. Tried to set the fuel mixture with the gauge and also tried to dial in the timing a little better. My gauge was still reading a low 15 so that is a little concerning. It would occasionally flicker a little too (maybe a half a number or so). It would only read 15 at a pretty high idle though, lower idle was around 12 or 13. Hoping for some insight on how to fix this a little or what might be causing it.

3. I looked at my vacuum advance hose again and I think it was attached to the wrong port on the carb according to the service manual for the carb I found online. I hooked it up to the right one now so that should help.

4. I sprayed carb cleaner around the carb and the top of the motor quite a bit today. It didn't seem to effect it much anywhere except for one spot and that was right behind the carb. It seemed like it might have had a tiny leak there. I tried tightening down the carb a bit more as well.

5. I will keep looking for vacuum lines I don't really need and cap them off. We'll see if I can cap off the EGR.

6. I will look a little closer at the intake. I might just take it off and get a new gasket, it's only $20 and I've already dumper enough money into this thing.


I was thinking about compression checking everything also, as I figure it can't hurt to check. I also was looking into the coil voltage today through the ballast resistor and the ecm as I was reading these can cause issues also. I read about 5 volts at the coil sitting and about 8 or 9 volts when the key is turned, however I have wired in my own push button and was going to hook 12 volts straight to the coil until I read about the ballast resistor. I guess I'm wondering if i should just run my toggle switch to the ballast resistor and run like a constant 5 volts to it. It will start up just fine on the 5 volts. Or are these numbers low and that ballast resistor bad? It' my understanding that the ballast resistor gives the coil a low voltage to use when the engine is running and then gives it more voltage when the motor is trying to turn over, is that correct?

Also with this thing always dying in gear right away is there any chance that my torque converter could be causing it to die? I don't think it is but just wondering if that is a possibility?

I'll keep chugging away at it and see what I can come up with. Thanks
 

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Vac seems low; could be timing, or idle throttle setting (not rpm) too high/OPEN (blades open too much), restricted/blocked exhaust, maybe even a stuck closed heat control valve (heat riser valve), orrr. ... For now, cure vac leak at back of carb and any others; spray/check EGR for leaks (best to get rid it and block it off, DONE).

... Definitely do compression test; good batt (and charger on it), all plugs out; I prefer WOT, and also count the strokes. (have heard of some who bump starter to comp? stroke, so test for all cyls start at the same point equally; good idea IMO).

... Would not do intake gaskets yet; I prefer to check/test them with premium/"Gold" Shell gas (contains no ethanol in my neck of the woods), good for other leaks too; CAREFULL!!!
 

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12" (15" at high idle) is very low. You should have 20-22 with a stock cam. There is definitely a vacuum leak. Like key99 said, ditch the EGR valve. Unbolt it, toss it in the trash and put a plate (with gasket) over the EGR mount.

Vacuum leak at back of carb could be gasket or unplugged port. Check that all unused ports on the carb have rubber caps over them. If leak is at the gasket you could try flipping the gasket over. If it still leaks then replace gasket. Don't forget to check brake booster (if you have power brakes) and PCV hoses. Try disconnecting brake booster and PCV and plug those ports as well to determine if those could be another source of vacuum leak.
 

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12" (15" at high idle) is very low. You should have 20-22 with a stock cam. There is definitely a vacuum leak. Like key99 said, ditch the EGR valve. Unbolt it, toss it in the trash and put a plate (with gasket) over the EGR mount.

Vacuum leak at back of carb could be gasket or unplugged port. Check that all unused ports on the carb have rubber caps over them. If leak is at the gasket you could try flipping the gasket over. If it still leaks then replace gasket. Don't forget to check brake booster (if you have power brakes) and PCV hoses. Try disconnecting brake booster and PCV and plug those ports as well to determine if those could be another source of vacuum leak.
Good idea; and as said, best to disconnect/plug items one at a time "at the intake/carb ports" (so no old hoses are involved in testing).
... Its kinda rare, but PCV valve can admit positive pressures into intake reducing vacuum, especially if engine has some blowby and/or crankcase fresh air inlet/vent is plugged/restricted (that positive pressure is gonna go somewhere!!)
... May have been mentioned; but test for leaks at booster fitting; it's old/brittle, maybe cracked, and old rubber grommet may be rock hard and leaking.

... DK, but don't think 76 had lockup torque converter (they sometimes have "clean/quick" stalling issues when put in gear).
... Unless you feel some movement/lurching when it's put in gear, would not suspect conv. ... Others will have far better conv info.

... If when put in gear, engine/rpm die clean/quick/evenly (like letting out a manual transes clutch too quickly), could suspect conv.
... But if it stumbles at all, and/or looses rpm slowly/unevenly like lean/lacks fuel, or flooding, suspect engine.
 

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Discussion Starter #11
Got the new cap, rotor and plug wires put in today. Didn't get a chance to do a compression test yet (need to borrow the tester) and it didn't seem to make much difference.

I sprayed some more carb cleaner around everything and it didn't seem to matter. Removed the brake booster hose and plugged it with my finger and the gauge didn't go up any. Also removed the main vacuum hose that goes to the booster and plugged that and also didn't make a difference. Do I even need anything that's hooked to the booster?

I'll have to take the EGR out when I get a chance I guess. The only vacuum line that I've noticed has made the engine run worse when unplugged is the PCV line, so that makes sense there but why the other ones don't change anything is beyond me.

With all that being said I took it for about a 20 mile trip today just for fun. It will run okay going down the road. Seems kinda poochy though. Top speed I could get to was 60 and that was pedal to the floor. It also sounded like it was at pretty high rpm at that point (It doesn't have a tach so I can't tell you the exact number). I was able to drive it just fine just as long as I popped it into neutral whenever I needed to stop. (Not the best situation)

It does seem to lurch when placed into gear but I think that is just from the idle being pretty high on it. And once I do put it into gear its either give it gas or it dies fast.

I didn't seem to have the leak at the base of the carb anymore once I tightened it down more. It is a brand new gasket there.

I will be busy for the next couple of weeks so I probably wont be able to mess with it for a while. I might even just leave it the way it is and run it that way until next summer. (It's a RV used for tailgating at football games so It gets used during the fall and that is about it. It only has to be able to drive 3 miles at a time, to the game and back to the parking spot.)
 

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Removed the brake booster hose and plugged it with my finger and the gauge didn't go up any. Also removed the main vacuum hose that goes to the booster and plugged that and also didn't make a difference. Do I even need anything that's hooked to the booster?

I'll have to take the EGR out when I get a chance I guess

The only vacuum line that I've noticed has made the engine run worse when unplugged is the PCV line, so that makes sense there but why the other ones don't change anything is beyond me.
Dk what else is hooked to booster, maybe vac supply line for HVAC controls.

For now, at least test/spray around the EGR rod, and also its diaphragm (may reduce chasing phantoms).

PCV valve (especially if dirty) provides some restriction; if "unplugged" the weak vacuum will drop even lower.
... PCV "consumes" vacuum most of the time; others only consume vac "momentarily" when they're applied (brakes, hvac)
 
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