**sigh** now what?
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**sigh** now what?
'74 F100 360 2bbl. with a rookie turning the wrenches. So I just replaced my cracked and leaking exhaust manifolds with headers....yea! Since I got the truck it hasn't ran much and is just now getting enough parts put back on it to be run-able.. It always missed a little at part throttle, but it didn't have any vacuum lines from the EGR or at the base of the carb. I re plumbed these and fixed the exhaust leaks hoping to see an improvement. I tried to drive it tonight. Not so good. The warmer the motor got, the worse it ran. Idle speed dropped to the point where it wouldn't run. It stalled a lot but would re-fire right away. The missing got really bad. I pop the hood and I see what appears to be coolant running from the intake manifold down the front of the drivers side cylinder head. I wiped it off and sure enough it came back after a little running. Would my motor run like this with a coolant leak? Are these two separate problems? Any thoughts on trouble shooting and/or advise would be really appreciated.
Todd
Todd
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Could you describe the coolant leak a little more clearly? Specifically where is it coming from?
As for the carb, it might be time for a rebuild, especially if air bleeds and jets are clogged. Good time to reset everything to spec, including the float height and choke.
Josh
As for the carb, it might be time for a rebuild, especially if air bleeds and jets are clogged. Good time to reset everything to spec, including the float height and choke.
Josh
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I can...standing at the grill looking at the motor, the leak is at the front of the engine at the junction where the intake manifold, cylinder head and block meet on the drivers side. The coolant will "seep" out here and run down the line formed by the head and block. I've never pulled the heads nor do I know much about FE motors, but can coolant get into bore from here and cause it to run really really bad? I just fixed a broken dipstick tube and didn't really notice coolant in the oil....not sure how I would know anyway unless it's really obvious.
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That is a somewhat common problem with FE engines. You'll need new intake gaskets to do the job, plus you'll likely need new valve cover gaskets as well.
As for the coolant, most likely it is contaminating the engine oil. Might not notice it on the dipstick if it is small quantities, however you might notice the oil level RAISING.
If the coolant is really pouring in there the oil should start looking like foamy mud.
Get ready for that intake though! Eat some Wheaties and do some stretches, the intake weighs 60+ pounds!
Josh
As for the coolant, most likely it is contaminating the engine oil. Might not notice it on the dipstick if it is small quantities, however you might notice the oil level RAISING.
If the coolant is really pouring in there the oil should start looking like foamy mud.
Get ready for that intake though! Eat some Wheaties and do some stretches, the intake weighs 60+ pounds!
Josh
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If you have coolant leaking from the intake manifold, you more than likely have a bad gasket. You may also be developing a vacuum leak from that same bad gasket, which would potentially cause it to run poorly.
It may also be that the bolts are loose on the manifold. If it were me, I'd try checking/ tightening those to spec first. If the problems went away or at least improved somewhat, I'd know for certain that the manifold was where the root of the issues lie.
Once it's warmed up, you you notice anything at the exhaust pipe(s)? Whitish smoke would indicate coolant infiltrating into one or more cylinders, and bluish smoke would indicate oil, obviously.
The fact that it runs more and more poorly the warmer it gets would indicate to me that it is more of a manifold vacuum problem than anything.
It may also be that the bolts are loose on the manifold. If it were me, I'd try checking/ tightening those to spec first. If the problems went away or at least improved somewhat, I'd know for certain that the manifold was where the root of the issues lie.
Once it's warmed up, you you notice anything at the exhaust pipe(s)? Whitish smoke would indicate coolant infiltrating into one or more cylinders, and bluish smoke would indicate oil, obviously.
The fact that it runs more and more poorly the warmer it gets would indicate to me that it is more of a manifold vacuum problem than anything.
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As always, thanks for everybody taking the time to help! I don't notice any abnormal smoke in the exhaust, so that's a good thing. Maybe the coolant leak isn't killing anything at the moment...although clearly I need to fix it. I was really concerned that this leak was causing the motor to run bad, but maybe that's not the root cause of the problem. I think the truck originally had a two diaphragm distributor, but now doesn't, so I had to kind of invent my own vacuum hose routing through the vacuum switches. Since it sort of runs all right when cold, could I have some vacuum lines crossed causing it really miss when warm?
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