81 New engine still getting hot on
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Joined: Jun 2006
Posts: 57
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From: Irvine California
81 New engine still getting hot on
-Took thermostat out and also checked to see if fluid present at the stat and the top rad hose and there was.
-let the car run with rad cap off, nose lifted to try to get the air out
- watched the rad which had good flow of fluid going through it.
- I took it out around the block to see if it would get any hotter, it maintained a warmer temp but not as hot as it was sitting still. but the biggest disappointment was that it no power.
No professional mech but I have ruled out the stat, water pump, and radiator for the temp problem. The only things I can think of is the timming, and/or the engine driven fan. Since the 81 has a computer is there any other settings on the timing, currently at 10. Emissions say 6 but it roughs really rough at idle and difficult to keep running. Any other suggestions???
-let the car run with rad cap off, nose lifted to try to get the air out
- watched the rad which had good flow of fluid going through it.
- I took it out around the block to see if it would get any hotter, it maintained a warmer temp but not as hot as it was sitting still. but the biggest disappointment was that it no power.
No professional mech but I have ruled out the stat, water pump, and radiator for the temp problem. The only things I can think of is the timming, and/or the engine driven fan. Since the 81 has a computer is there any other settings on the timing, currently at 10. Emissions say 6 but it roughs really rough at idle and difficult to keep running. Any other suggestions???
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Well... since you diddnt state what "New engine" you have installed and where you are from (thats what your profile is for) I cant give much advice concerning losing the computer and putting a different Carb on your car as far as emission control/inspection goes in your state
Sorry
Sorry
Intermediate
Joined: Jan 2005
Posts: 35
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From: Las Vegas Nevada
Is it a three or four core radiator?
Fan shroud in place, and proper size fan?
I was haveing problems with my 78 and it turned out that
the previous owner "Bubba" put a 16.5 inch fan and it needed a 18.
I put in the 18 inch and no more over heat and I live in vegas.
How long before it over heats?
Fan shroud in place, and proper size fan?
I was haveing problems with my 78 and it turned out that
the previous owner "Bubba" put a 16.5 inch fan and it needed a 18.
I put in the 18 inch and no more over heat and I live in vegas.
How long before it over heats?
Melting Slicks
Joined: Mar 2006
Posts: 2,465
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From: Orange Park Fl
If an '81 has a flat tire, everyone immediately blames the CCC system. The system works fine and is an upgrade over earlier set ups for street use. If your engine runs rough at 6 BTDC, you need to find out why. I set mine at 10 before, but it runs fine at 6. Use a factory service manual and go through the diagnostic littany to find the real problem, then you will know what is needed to fix it. God bless, Sensei
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From: San Diego CA
Originally Posted by a1sensei
If an '81 has a flat tire, everyone immediately blames the CCC system. The system works fine and is an upgrade over earlier set ups for street use. If your engine runs rough at 6 BTDC, you need to find out why. I set mine at 10 before, but it runs fine at 6. Use a factory service manual and go through the diagnostic littany to find the real problem, then you will know what is needed to fix it. God bless, Sensei
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Joined: Jun 2006
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From: Irvine California
Originally Posted by Kalway
Notice he has a new engine. The CCC system doesn't like certain cams and especially hates low vaccuum. However, I'm going to bet he likely has a vaccuum leak somewhere.
- Timing done as per the factory specs 6 BTDC done step by step as the factory label says to set. Runs smooth and has the power and get up that it should. No problem starting always on the 1st try it fires.
- New water pump and hoses with no thermo to check for good flow back to the rad. But with the engine getting as hot so quick I not sure putting it back in right now would help any.
- 18" fan with new fan clutch, along with aux fan
- Flushed out Rad prior to re installing back in to car, I could not tell you how many cores it has. Can feel good air flow coming through the rad. I belive it is the original rad that was but on for 81s so that is the next replacement in my book.
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Joined: Jun 2006
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From: Irvine California
Originally Posted by merrell.a
The engine is the stock 81 350 5.7, just had it rebuilt a week ago. Here is the list of things i done to check it out. All done while sitting still, drove around the block to see if it would help with more air coming acrossn but it just stabled our just above tehe red.
- Timing done as per the factory specs 6 BTDC done step by step as the factory label says to set. Runs smooth and has the power and get up that it should. No problem starting always on the 1st try it fires.
- New water pump and hoses with no thermo to check for good flow back to the rad. But with the engine getting as hot so quick I not sure putting it back in right now would help any.
- 18" fan with new fan clutch, along with aux fan
- Flushed out Rad prior to re installing back in to car, I could not tell you how many cores it has. Can feel good air flow coming through the rad. I belive it is the original rad that was but on for 81s so that is the next replacement in my book.
- Timing done as per the factory specs 6 BTDC done step by step as the factory label says to set. Runs smooth and has the power and get up that it should. No problem starting always on the 1st try it fires.
- New water pump and hoses with no thermo to check for good flow back to the rad. But with the engine getting as hot so quick I not sure putting it back in right now would help any.
- 18" fan with new fan clutch, along with aux fan
- Flushed out Rad prior to re installing back in to car, I could not tell you how many cores it has. Can feel good air flow coming through the rad. I belive it is the original rad that was but on for 81s so that is the next replacement in my book.
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Joined: Jun 2006
Posts: 57
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From: Irvine California
Originally Posted by Bob Onit
Well... since you diddnt state what "New engine" you have installed and where you are from (thats what your profile is for) I cant give much advice concerning losing the computer and putting a different Carb on your car as far as emission control/inspection goes in your state
Sorry
Sorry
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Joined: Jun 2006
Posts: 57
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From: Irvine California
Originally Posted by Kalway
Notice he has a new engine. The CCC system doesn't like certain cams and especially hates low vaccuum. However, I'm going to bet he likely has a vaccuum leak somewhere.
