engine and drivetrain All of a sudden no idle, running hot

[johns1974]

PREFACE--

Please excuse my ignorance on what most of you will likely consider basic stuff/symptoms...

After many miles of great running, I just filled up the tank and now the car won't hold an idle at any temperature. It just drops stone dead. It doesn't even try to stay lit. Cold, Warm or Hot it's all the same...

Also, the car is running quite a bit hotter than usual and getting very near the red after 20 minutes or so regardless of speed/traffic/airtemp.

Also, there is a loud series of "PPFFFFFTTTT" sounds (almost like tiny backfires) that continuously pop whenever the car is under engine braking, particularly at higher RPMs

The car still runs very strong and smooth when my foot is in it.

It's a real strong motor, e21 head, 38/38 weber, electronic ignition (crane), and all new filters all around (fuel, air etc.) It was running great before my last fill up...

Could all this be caused by a bad tankful of gas? Does it sound like a carburetor issue? Engine timing? I'm at a loss as to why this would all happen at once when none of these sysmptoms existed 2 days ago... Would a can of octane booster help (if it is a fuel issue)?

Any guidance on where to start would be ever so much appreciated. Thanks

[c.d.iesel]

yer ignition timing has 'slipped'

or carb jets have come loose?

carb jets blocked?

float level has changed - overflowing fuel?

look down into the carb while it's idling and report back

see if when you adjust the carb idle mixture screws you get a running

change with just 1/4 turn of the screw

if no running change with 1 to 2 turns in or out - you have an 'issue'

have you looked into the radiator ? - level?

over flowing?

looked into the oil filler cap ? do you see whitish foamy mix with the oil ?

fan belt loose?

any leakage from the bottom of the water pump - just behind the belt pully?

[FL02]

Might be a stuck thermostat. I've had overheating issues with a bad thermostat. Doesn't change the idle though. I agree with CD in that you should check the idle mix screw or see if you distributer is loose and is out of time. Otherwise CD is right about maybe a clogged fuel line, carb jet or bad float level. Good Luck.

[johns1974]

thanks, c.d.

Now here comes the inevitable series of "sincere but stupid questions of the year":

How do I "unslip" it?

Which way do I turn the distributer?

How far?

With the engine running or no? (I'd have to get someone to hold the throttle open for me, i suppose)

Can I just grab it and twist, or do I need to loosen a screw (or other similar doodad) that might hold it in place?

FWIW, I don't have a timing light (wouldn't know how to read it if I had one)...

For anyone willing to show the patience to hold my hand through this, THANK YOU!

[johns1974]

c.d.,

I need to take an auto shop course (or a 1,000) to even grasp what you are referring to most of the time!! I don't know the first thing about carb jets, mixture screws, or floats.

I can tell you:

there is no over flowing fuel,

the radiator is level, full, and still a good color

there is no foaminess in the oil filler cap

the fan belt is tight

and there are no leaks, at all, from the water pump or anywhere else.

BTW... I smile everytime I read your posts because everytime I read one, I'm reminded how much I wish I knew! But I'm like a 3rd grader talking to a professor emeritus...

[Anschauer]

http://www.02restoration.com/restoration-tips/fuel-and-exhaust/clogged-idle-jet/

[c.d.iesel]

Well john - you just placed the apple

on the teachers desk !. Thank you for the compliments

I feel your need to learn and you have a great life ahead of you with

the attitude that you exibit.

Wish I were closer - but wait a little longer and

hopefully you find a 02 neighbor willing to spend some time with you.

The public library usually containd very dated general automotive

'how to' books showing you the basics that you need about timing light operation, carburetor basics,

and other topics that will help you understand the basics of Motor compression, ignition, cooling system, carburetion/fuel injection,

drive train .

<<<<<<<<<<<><>>>>><>>>>>>>>>>>>>>>>>>>>>>>>>

I need to take an auto shop course (or a 1,000) to even grasp what you are referring to most of the time!! I don't know the first thing about carb jets, mixture screws, or floats.

I can tell you:

there is no over flowing fuel,

the radiator is level, full, and still a good color

there is no foaminess in the oil filler cap

the fan belt is tight

and there are no leaks, at all, from the water pump or anywhere else.

BTW... I smile everytime I read your posts because everytime I read one, I'm reminded how much I wish I knew! But I'm like a 3rd grader talking to a professor emeritus...

----------------------------------------------------------------

at least you have looked at a few of the 'basics'

and we can zoom in closer to your poor running cause. . . . .

_________________

[FL02]

Turn the distributer counter clockwise a bit if it's slipped, but it could mess you up. But if the bolt is loose that holds it into place then it might be the problem. My car doesn't run good on 10% Ethanol and you might need to richen up the carb some by turning the idle mix screw counter clockwise a bit. Stock carb settings on a weber 32/36 are 2 1/2 turns out, but if it is too rich it will feel sluggish and too lean will feel tight and shaky when it revs. Might want to check to make sure you are close to the 2 1/2 idle mix screw stock setting and go from there. Wouldn't do anything too drastic with the distributer unless the little screw holing it on is loose. I sorta 'Italian' tune mine by feel. Advance is clockwise and counter is retard on the distributer. To far avance will either start super quick, or not at all, to far retard will start slow and rob you of power. What I did was find a nice place on the carb where the revs were right and it shifts smooth without grinding gears and turn the distributer a bit one way or the other to smooth out the engine 'Italian' style. Then I'll start it again to make sure I'm not too far advance, drive it and test it with my right foot and shifter hand. ;-)

Anyway, if the distributer bolt is loose then it might be too far advance, other wise it's a carb/fuel/Air issue...

[Jaycen_PNW2002]

Does your 32/36 have on of these.? If so has it come undone? If you have one it will be attached to the idle jet on the passenger side of the car. Check to make sure the wire to this solenoid is still fastened.

[johns1974]

I have a 38/38 so I don't know if that solenoid is the answer... Does a 38/38 have one? I'll look into that. It does feel, to me, like a carb/fuel issue but I need to learn more about the way distributers work...

I'll be tinkering this weekend and hope I don't screw things up too bad! I live in fear of making things worse, especially if it is something super simple. Thanks!

[penth2o]

Mark that dizzy before you go twisting it so you can get back to the original point when all else fails.

[Chris_B]

So, the "there is a loud series of "PPFFFFFTTTT" sounds (almost like tiny backfires) that continuously pop whenever the car is under engine braking, particularly at higher RPMs " is kind of strange. Check for a loose spark plug, or maybe an air leak on the intake system, like a vacuum hose that has come off or has a hole/crack. A lean condition from an air leak could have an effect on the idle, and make the motor run hot.

[rogerspeed]

to add to the masters diagnosis, the sound under engine braking could be unburned fuel igniting in the exhaust system, bad ignition timing will increase the unburned fuel in the exhaust system (and cause overheating), you may also want to look for exhaust leaks which will provide the oxygen to help create the burning of fuel in the exhaust system.

[jgerock]

Hey CD - maybe you can add a Weber carb. graphic to this post that shows the adjustment screws (if you have one).

John: Do you have any kind of manual for your car? All manuals (even the BMW owner's manual) have great pictures showing the locations of all the areas you need to inspect. Whatever you do, pick only (1) thing to inspect/change at a time. This is the only way to correctly diagnose a problem.

I'm curious as to the problems with your car. Good luck and keep us informed.

[johns1974]

for those who are interested here's what I got accomplished... Just because my gut told me that the last gas fill up might have been the culprit, I drained the tank down to about 1/4 tank (using the old fashioned siphoning method) and then refilled with 5 gallons of chevron 91 octane. Then I took all of your advice about an "italian tune-up" and went for a spirited drive...

Idle is much better now and actually holds where it is supposed to! The "PFFT" sounds that existed under engine braking are also much reduced. But it did get warm again (about a 1/4 inch from the red)... so that is something i'll be looking into... maybe a radiator swap from Mr. Ingraham is in my immediate future. (a search of the archives tells me they are the best, by far... I'll be asking you all for any tips tricks to this but I'm hoping it is a bolt-for-bolt transplant and not too complicated)

I'll try to dig a little deeper as I have time next weekend but I feel OK getting back and forth to work this upcoming week. Thanks to all for your generous support of this complete rookie.

And maybe there is something to be said for buying good gas from the same station with these old cars. Thanks again,

-john