Overheating
Thread Starter
Heel & Toe
Joined: Mar 2012
Posts: 22
Likes: 0
From: Scotts Michigan
Somethings not right here. This doesn’t sound like purely an overheating issue. 210-220 degrees is warm, but it’s hardly overheating and certainly not enough to cause the engine to quit. Not sure what but something else is going on here.
I’m thinking I would start with the basics: compression test, leak down, timing. Then go from there. If I had to hazard a guess I’m thinking head gasket??
I’m thinking I would start with the basics: compression test, leak down, timing. Then go from there. If I had to hazard a guess I’m thinking head gasket??
Thread Starter
Heel & Toe
Joined: Mar 2012
Posts: 22
Likes: 0
From: Scotts Michigan
I just reread that, over heating is 240/260 plus and blowing steam everywhere. IF it just gets to 210/220 then stalls its a heat related issue. It sounds like it wold be an delectrical or fuel related issue. Maybe you have a bad coil, a cracked cap, youre vapor locking, or have a fuel pump issue.
Edelbrocks are known for being heat sensitive and needing low fuel pressure, but it doesnt account for the temperature increase. If you have the quadrajet, thow it back on and see if the temp isssue goes away. The stalling may just be a symptom of the overheating, or the stalling is a symptom of something else and the overheating is also a symptom of that other problem. So elimate possible causes. Start with the carb and then check your tune up. if changing that doesnt do it you may have to get your radiator flushed. Maybe its flowing enough to stay cool at idle rpm ,but not at 3000 rpm. If there is alot of mud in your system you may have to flush it 3 times, i had to in my old motor.
Edelbrocks are known for being heat sensitive and needing low fuel pressure, but it doesnt account for the temperature increase. If you have the quadrajet, thow it back on and see if the temp isssue goes away. The stalling may just be a symptom of the overheating, or the stalling is a symptom of something else and the overheating is also a symptom of that other problem. So elimate possible causes. Start with the carb and then check your tune up. if changing that doesnt do it you may have to get your radiator flushed. Maybe its flowing enough to stay cool at idle rpm ,but not at 3000 rpm. If there is alot of mud in your system you may have to flush it 3 times, i had to in my old motor.
working on flushing it tonight. Rather drained it and then all the family stuff happens so I will get it done tomorrow after work. A thought about the fuel crossed my mind about that being hot/flooding the carb or the filter being clogged already despite being it being new. But I’m new at most of this and never been experienced at diagnosis with engine issues.
Thread Starter
Heel & Toe
Joined: Mar 2012
Posts: 22
Likes: 0
From: Scotts Michigan
im not seeing one. Had it converted to straight pipe in 2012 and it may have broken before that.
Melting Slicks
Joined: Oct 2012
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From: Dunedin NZ.
Assuming you don't have an air leak somewhere do you know if the carb is supplying the correct air fuel ratio above idle that your engine needs? Typically most carbs out of the box seem to be jetted on the rich side but what is yours like? A lean mixture will make the engine run hotter.
Race Director
Joined: Mar 2017
Posts: 11,801
Likes: 4,421
From: Virginia
A few more questions that may help:
Do you have an infrared thermometer to check your temperature? I found that shooting at the upper radiator hose gave me my most consistent results (compared to a thermocouple taped to the hose). Clearly something is happening, but the exact number is helpful to know.
What is your timing set to? If you haven't already, it is worth it to email @lars (post 15) and ask for his timing papers, as well as his distributor and Q-Jet setup papers. Going through his timing method (Not stock, but much better), may well fix your problem, and it is certainly easier to do than swapping a carb.
Do you have an infrared thermometer to check your temperature? I found that shooting at the upper radiator hose gave me my most consistent results (compared to a thermocouple taped to the hose). Clearly something is happening, but the exact number is helpful to know.
What is your timing set to? If you haven't already, it is worth it to email @lars (post 15) and ask for his timing papers, as well as his distributor and Q-Jet setup papers. Going through his timing method (Not stock, but much better), may well fix your problem, and it is certainly easier to do than swapping a carb.
Thread Starter
Heel & Toe
Joined: Mar 2012
Posts: 22
Likes: 0
From: Scotts Michigan
Assuming you don't have an air leak somewhere do you know if the carb is supplying the correct air fuel ratio above idle that your engine needs? Typically most carbs out of the box seem to be jetted on the rich side but what is yours like? A lean mixture will make the engine run hotter.
Thread Starter
Heel & Toe
Joined: Mar 2012
Posts: 22
Likes: 0
From: Scotts Michigan
A few more questions that may help:
Do you have an infrared thermometer to check your temperature? I found that shooting at the upper radiator hose gave me my most consistent results (compared to a thermocouple taped to the hose). Clearly something is happening, but the exact number is helpful to know.
What is your timing set to? If you haven't already, it is worth it to email @lars (post 15) and ask for his timing papers, as well as his distributor and Q-Jet setup papers. Going through his timing method (Not stock, but much better), may well fix your problem, and it is certainly easier to do than swapping a carb.
Do you have an infrared thermometer to check your temperature? I found that shooting at the upper radiator hose gave me my most consistent results (compared to a thermocouple taped to the hose). Clearly something is happening, but the exact number is helpful to know.
What is your timing set to? If you haven't already, it is worth it to email @lars (post 15) and ask for his timing papers, as well as his distributor and Q-Jet setup papers. Going through his timing method (Not stock, but much better), may well fix your problem, and it is certainly easier to do than swapping a carb.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,112
From: Crossville TN
If it does not overheat during idle condition or a low cruising speed, but it overheats once you increase speed to highway conditions, chances are the [steel] sping in the lower radiator hose (keeps that hose from collapsing at higher speeds) has rusted/rotted away. When the engine is OFF and cold, grab that lower hose in the middle and give it a good squeeze. If it does not resist changing shape, you have no sping inside it. Unless you have a corrugated hose (non-collapsing by design), put the required spring in it and your problems may disappear.
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Melting Slicks
Joined: Dec 2009
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From: Thunder Bay
If it does not overheat during idle condition or a low cruising speed, but it overheats once you increase speed to highway conditions, chances are the [steel] sping in the lower radiator hose (keeps that hose from collapsing at higher speeds) has rusted/rotted away. When the engine is OFF and cold, grab that lower hose in the middle and give it a good squeeze. If it does not resist changing shape, you have no sping inside it. Unless you have a corrugated hose (non-collapsing by design), put the required spring in it and your problems may disappear.
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That carb may be vapor locking at that temp possibly..... My edelbrocks never stalled like that but they would be hard starting when the ambient air temp was high, I had to go to a wood spacer to keep the heat away from the carb, but I have a L88 hood, so clearance wasnt an issue for me. I also had to intall a pressure regulator.
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Or if he fixes the quiting, the heat will dissapear............
Dr. Detroit
Joined: Mar 2012
Posts: 10,090
Likes: 4,015
From: New Braunfels Texas
Please get rid of that square bore to spread bore adapter you installed. Those are just the most terrible thing and you will never get it to run right.
Buy either a 2101 or 2701 edebrock intake, and use 1204 intake gaskets or put the Q-Jet back on. Either intake is EGR delete and the 1204 will block the nasty heat riser passage in the heads off. I would get the intake.....the AVS2 is a nice carb.....although most do not agree with me.
The above timing recommendations need to be done before you can do anything else......
Jebby
Buy either a 2101 or 2701 edebrock intake, and use 1204 intake gaskets or put the Q-Jet back on. Either intake is EGR delete and the 1204 will block the nasty heat riser passage in the heads off. I would get the intake.....the AVS2 is a nice carb.....although most do not agree with me.
The above timing recommendations need to be done before you can do anything else......
Jebby
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Le Mans Master
Joined: Dec 2006
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If I am reading this correctly, the issues started with the carb swap. I would go back to square one, and reinstall the quadrajet.
The Edelbrock may be lean, or the float is incorrect, and its lean/starving for fuel.
Put it back, check ignition and timing, and go from there.
Any other maintenence like flushing cooling system, fresh coolant, etc will do no harm.
Jebby is spot on about the adapter non sense.
The Edelbrock may be lean, or the float is incorrect, and its lean/starving for fuel.
Put it back, check ignition and timing, and go from there.
Any other maintenence like flushing cooling system, fresh coolant, etc will do no harm.
Jebby is spot on about the adapter non sense.
Melting Slicks
Joined: Dec 2009
Posts: 3,195
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From: Thunder Bay
When I read the original post, I got the impression the 'overheating' started after he installed the carb. Perhaps the OP will chime in and clarify?