New to me 78 NYB on its way but please Don't tell my wife
- Thread starter 73 T&C
- Start date
Puzzler and possible issues to resolve and chase down.
Worked all day Saturday on my NYB. (See sinking feeling thread) I’ve also been driving my ‘73 T&C And I’ve come to a few possible conclusions.....
I’m not getting the NYB to run as good as the wagon..... smooth wise. And the T&C is about ready for a tune up at that. Minor stuff just oil change, carb cleaning (no issues), cap, rotor, wires and plugs, General policing.
The ELB on the New Yorker is working as it should. Under power, she pulls smartly. She’s not running hot. New everything regarding ignition. Even NOS hotter plugs.
She just doesn’t feel right. She won’t hold a smooth spec idle and needs to be set about 850 in neutral to get a slightly off idle in gear at a strong 675. She bangs slightly into gear and I hate that. NFG. She has a minor but noticeable vibration above 2800 RPM that is also NFG. Like a harmonic balancer out of balance... or a weak cylinder...not pronounced but there.
I’m noticing a loss of coolant from the reservoir. She warms up fast from stone cold.
Engine vacuum:
Engine produces just under 17 in.Hg in neutral with A/C load.
And just over 17 in. With no load. Needle is very steady. In gear it drops to 12-13 and a little wavering. Accelerated from a standing start, engine vacuum drops to 6 but pops up when you get to speed. (I used a Very long vacuum hose) And again down to 10 or less at throttle tip in (depending on amount you tip)
Whatever is going on, I’m chasing too many varying variables. Set warm she runs poorly cold. Set cold she runs too fast warm. Transition is almost ok but not acceptable and....it ain’t the ELB. She’s warming up the coolant too fast and knocking out the cold idle enrichment too soon is my guess.
I’m thinking I’ve either got a blown (leaking or blowing) head gasket, burned exhaust valve, spun cam lobe, very weak intake lifter bent pushrod(s) or a combination of the above.
I’m going to go for a valve covers off leak down test and measure out the rockers travel.
Somebody did the heads on this car and it wasn’t me.
On the good side... the A/C works great! If only the engine ran as well.
My gut tells me it’s a bad cylinders head gasket that is leaking. From just turning off each cylinder at the distributor, least change was cylinder #4.
I will get this puzzle solved.
J
Worked all day Saturday on my NYB. (See sinking feeling thread) I’ve also been driving my ‘73 T&C And I’ve come to a few possible conclusions.....
I’m not getting the NYB to run as good as the wagon..... smooth wise. And the T&C is about ready for a tune up at that. Minor stuff just oil change, carb cleaning (no issues), cap, rotor, wires and plugs, General policing.
The ELB on the New Yorker is working as it should. Under power, she pulls smartly. She’s not running hot. New everything regarding ignition. Even NOS hotter plugs.
She just doesn’t feel right. She won’t hold a smooth spec idle and needs to be set about 850 in neutral to get a slightly off idle in gear at a strong 675. She bangs slightly into gear and I hate that. NFG. She has a minor but noticeable vibration above 2800 RPM that is also NFG. Like a harmonic balancer out of balance... or a weak cylinder...not pronounced but there.
I’m noticing a loss of coolant from the reservoir. She warms up fast from stone cold.
Engine vacuum:
Engine produces just under 17 in.Hg in neutral with A/C load.
And just over 17 in. With no load. Needle is very steady. In gear it drops to 12-13 and a little wavering. Accelerated from a standing start, engine vacuum drops to 6 but pops up when you get to speed. (I used a Very long vacuum hose) And again down to 10 or less at throttle tip in (depending on amount you tip)
Whatever is going on, I’m chasing too many varying variables. Set warm she runs poorly cold. Set cold she runs too fast warm. Transition is almost ok but not acceptable and....it ain’t the ELB. She’s warming up the coolant too fast and knocking out the cold idle enrichment too soon is my guess.
I’m thinking I’ve either got a blown (leaking or blowing) head gasket, burned exhaust valve, spun cam lobe, very weak intake lifter bent pushrod(s) or a combination of the above.
I’m going to go for a valve covers off leak down test and measure out the rockers travel.
Somebody did the heads on this car and it wasn’t me.
On the good side... the A/C works great! If only the engine ran as well.
My gut tells me it’s a bad cylinders head gasket that is leaking. From just turning off each cylinder at the distributor, least change was cylinder #4.
I will get this puzzle solved.
J
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commando1
Old Man with a Hat
I'm here for you, Jav, Just say the word.
Thanks Stan! I think I have this.... but please feel free to call me or chime in with any advice.
I really wish I had driven your NYB when I had the chance to ask. Just for comparison.
I was a car jockey as a kid and remember driving an NYB (77 I think) and it was as smooth and powerful... more so really... than my Dad’s 79 Sedan De Ville. It left a very nice impression as I remember...
That’s what I’m after and I know I’ll get there.
Just went to get milk in the wagon... big f’ing difference. Soooooo smooth.
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IIRC, you have a scope available. Put the scope on Parade/Display and set the voltages so they stay on screen during power braking. A lower spike (firing line) on #4 would help confirm the idle speed bower balance.
You could also make a quickie EGR block off from flat steel to assure that it isn't bleeding any exhaust gases. At low speed (idle/off idle) EGR will make a big difference in smooth running. At the cost of a gasket, the best test I have for you... a 4/5 gas analyzer would show higher HC's, but would be a bit subjective and easy to confuse with other problems.
Here is a fair enough overview of a dynamic compression test... I know you can research from here...
Dynamic Compression Test
Running Compression Tests - ALLDATA Support
Hope this helps
commando1
Old Man with a Hat
Seriously, Jav, I am not trying to rub your nose in it.
I have the NYB running and feeling like it's 1976.
Mostly because I was was like a monkey at a typewriter. Keep banging away cluelessly and eventually Shakespeare pours out.
I was dumb and forgot to have you drive it. I was too wrapped up in your Citroen. Lol.
In all honesty, I am doubtful that trying to keep the engine 100% original and running as new is going to be easy, if not frustrating.
One example is when I finally caved, shitcanned the V-twin compressor for a Sanden. I was able to drop the idle 200 RPM
!I doubt I could have achieved a perfect idle in a 100 yrs. otherwise.
And yet.... my wagon is smooth with the compressor on and almost imperceptible with the compressor off. That’s what I’m looking for.Seriously, Jav, I am not trying to rub your nose in it.
I have the NYB running and feeling like it's 1976.
Mostly because I was was like a monkey at a typewriter. Keep banging away cluelessly and eventually Shakespeare pours out.
I was dumb and forgot to have you drive it. I was too wrapped up in your Citroen. Lol.
In all honesty, I am doubtful that trying to keep the engine 100% original and running as new is going to be easy, if not frustrating.
One example is when I finally caved, shitcanned the V-twin compressor for a Sanden. I was able to drop the idle 200 RPM
I doubt I could have achieved a perfect idle in a 100 yrs. otherwise.
70bigblockdodge
Old Man with a Hat
So should I pull the Schrader valve or not. What way do you do it?
I've not left the schrader in to know... out and you don't have to babysit the gauge...
In should be fine too, but you might miss random issues like worn valve guides.
Remember, the key to any compression test is comparative readings... if you have a compatible leak down tester... you don't pull the schrader, just change hoses.
That compressor has everything but a kick start and spark plug... but is, in my mind, a Moper trademarkSeriously, Jav, I am not trying to rub your nose in it.
I have the NYB running and feeling like it's 1976.
Mostly because I was was like a monkey at a typewriter. Keep banging away cluelessly and eventually Shakespeare pours out.
I was dumb and forgot to have you drive it. I was too wrapped up in your Citroen. Lol.
In all honesty, I am doubtful that trying to keep the engine 100% original and running as new is going to be easy, if not frustrating.
One example is when I finally caved, shitcanned the V-twin compressor for a Sanden. I was able to drop the idle 200 RPM
I doubt I could have achieved a perfect idle in a 100 yrs. otherwise.
. It'll stay on the Imperials as long as I find it practical to keep one... the sanden could happen to the parts car one day.BTW... I haven't produced anything close to Shakespeare yet... gotta keep banging
Hey Jeff,
No EGR valve in this car. It’s blanked off
Among the crazy things running through my mind is an underside intake manifold crack or leak. It fits the symptoms in that the evenness of the idle gets better after a full heat cycle if I don’t wait too long to start the car.
No EGR valve in this car. It’s blanked off
Among the crazy things running through my mind is an underside intake manifold crack or leak. It fits the symptoms in that the evenness of the idle gets better after a full heat cycle if I don’t wait too long to start the car.
Hey Jeff,
No EGR valve in this car. It’s blanked off
Among the crazy things running through my mind is an underside intake manifold crack or leak. It fits the symptoms in that the evenness of the idle gets better after a full heat cycle if I don’t wait too long to start the car.
No EGR valve in this car. It’s blanked off
Among the crazy things running through my mind is an underside intake manifold crack or leak. It fits the symptoms in that the evenness of the idle gets better after a full heat cycle if I don’t wait too long to start the car.
commando1
Old Man with a Hat
What the hell is up with that long hose from the PCV?
Where is it going to?
And what the hell is this?
70bigblockdodge
Old Man with a Hat
Goes to manifold vacuum on front of carb.
That's the check valve that Bob was talking about. Tube goes down to exhaust manifold.
Aahhh the ever popular air aspirator....should be an air pump below the PS pump IIRC
Thanks been working on my 79 360 for so long it looked similar.
First.. PVC line is a little long. So sorry Will trim accordingly.
Second, its the air valve aspirator for the exhaust. It’s connect to the back of the exhaust manifolds to introduce air into the exhaust stream. Helps light off the catalytic converter and raise the exhaust temp.
My catalytic is gone. It draws no power so I left it. It’s working fine.
PVC hose is too long... my apologies. Replaced the carbonized original and left it too long. Will trim accordingly.
No air pump. The shiny thing is the exhaust Check valve to allow air intake that is connected to the back of the intake manifold. It’s meant to introduce air into the exhaust stream to help light off the catalytic converter. It raises the exhaust temp.
I don’t have a catalytic converter but this draws no power so I left it.
Here’s the emission control diagram....
No air pump on this car and no EGR....
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