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Old 07-16-2018, 11:10 PM   #1
faun_cee
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Truck cranks but does not Start... BLown head? bad carb? off timing?

I don't want to give TOO much detail, so you guys can ask me questions rather than just throwing a bunch of diagnoses at me.
-1969 250 I6; monojet carb.

here's what I know that is not right.

-Motoroil smells somewhat like gas. I read if the carb is not adjusted correctly gas can leak down. it is a rebuilt carb by me, so I wouldn't put it past me that there is something wrong with it. It was running for a while after the rebuild. How do I adjust the carb? (video link will help tremendously)

-most Spark plugs were black when I pulled them off, smelling like the motor oil/gas smell. one seemed to have rust from water in the gas tank (the tank/truck sat outside for about 15 years.)

-I think it may have a blown head simply because of sitting for so long and when i had the chance to drive it, i believe it overheated.

-I'm thinking it may be out of timing, not sure how that could have happened. How can I know?

Should I change the distributor to an HEI in the process of checking all this? or just try to get it started with the distributor it has?



Ill try to upload pictures of the spark plugs, motor oil, and points.
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Old 07-16-2018, 11:27 PM   #2
faun_cee
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

Here are the pics.
Also the oil is above full.
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Old 07-16-2018, 11:44 PM   #3
bill3rail
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

Bad carburetor can fill your oil with fuel.
If all the plugs look like that, it is not too bad. I have seen ten times worse than that in the recent past.

First off, you must start with one issue at a time!

Does it have spark?

Do all cylinders have compression? How much pressure in each?

Is it getting fuel? Too much as you hinted towards is a problem.

Just some quick thoughts before I fall asleep.

Bill
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Old 07-16-2018, 11:59 PM   #4
Steeveedee
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

My recommendation-

1. Do not put an HEI in it until you have found the root problem. It will NOT make it run any better, at this point.

2. Before you run it too much, drain the oil to get rid of the diluted mixture. You might be buying rod and main bearings in your near future. if it hasn't run since the gas was in the oil, you're probably OK.

3. Get the carburetor checked out by a professional. I know that we like to do it ourselves, but it seems like it wasn't done right. No offense intended- I've screwed up on carburetors in the past.

It's past my bed time, so I'll let someone else school you on the necessary steps for checking out the ignition.
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Old 07-17-2018, 06:13 AM   #5
Grumpy old man
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

1 ) drain the old oil and replace with new filter , Take a few pictures with the air cleaner off to show current condition .
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Old 07-17-2018, 09:16 AM   #6
OldBlue70C10
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

Sounds to me like the float is probably sticking, so it's flooding the engine. Maybe its set too high? Or maybe the needle seat isn't just right and its letting fuel by? That's not too hard to check. That would explain the fuel in the oil, and also the not starting if it's flooding? Definitely drain the oil and get that fuel out of there.
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Old 07-19-2018, 10:31 AM   #7
faun_cee
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Re: Truck cranks but does not Start... BLown head? bad carb? off timing?

I was finally able to get to the carb...its not what I wanted to see. Water had rusted a lot of the parts, so I think for it might be cheaper to buy a new one for $100. I should have taken pictures, but ill try to when I get home.

The float was super high so i just practiced making it correct.

I most likely wont get to the rest of the check list til about friday or saturday.

Thanks for all the advice, it was super helpful.
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