86 monte ss 454

[Texas82GP]

Skip down to my second paragraph and try that test first. I would reformat this post but I'm on my phone so it's a pain.

You've got a short to ground somewhere. You're going to have to do a visual inspection under the dash and under the hood. Use the wiring diagram I posted to help identify what color wire is what. My guess is there is either a chaffed wire (insulation damaged) or someone has done some work on the wiring and made a mistake. My gut says it could be on either end since 1, the car's had a big block put in it so maybe something got pinched or maybe something didn't get hooked up and burned on exhaust and is now laying on ground, or there was a repair that is a mistake. Or 2, if there is an aftermarket stereo in the dash then the problem could be there. Maybe a wire is broke and shorting on the metal inner structure of the dash. If it were me, I would pull the radio and pull the climate control. I would study the wiring diagram to determine what is getting power when the mode selector is moved and then test each of the wires to identify which one has continuity to ground. Once you know which wire is bad, then you only have to find the bad spot and repair it. Look for a loose or pinched wire on either end.

Something I just remembered from a previous thread......There was another fellow on here who had the same problem. It turned out to be the A/C clutch cycling switch on the accumulator shorted to ground. Here's how to test: First unplug the connector from the cycling switch. Replace the blown fuse. Turn on the key and see if the fuse blows when you move the climate control mode selector switch. If the fuse doesn't blow, turn off the key and the mode selector switch. Now install a jumper wire across the connector for the clutch cycling switch. Now turn on the key and then turn on the mode selector switch. If the fuse still doesn't blow, replace the A/C clutch cycling switch and you should be good to go.

Let us know what you find and we can take it from there. Hope this helps.

 

[Nathan454]

Skip down to my second paragraph and try that test first. I would reformat this post but I'm on my phone so it's a pain.

You've got a short to ground somewhere. You're going to have to do a visual inspection under the dash and under the hood. Use the wiring diagram I posted to help identify what color wire is what. My guess is there is either a chaffed wire (insulation damaged) or someone has done some work on the wiring and made a mistake. My gut says it could be on either end since 1, the car's had a big block put in it so maybe something got pinched or maybe something didn't get hooked up and burned on exhaust and is now laying on ground, or there was a repair that is a mistake. Or 2, if there is an aftermarket stereo in the dash then the problem could be there. Maybe a wire is broke and shorting on the metal inner structure of the dash. If it were me, I would pull the radio and pull the climate control. I would study the wiring diagram to determine what is getting power when the mode selector is moved and then test each of the wires to identify which one has continuity to ground. Once you know which wire is bad, then you only have to find the bad spot and repair it. Look for a loose or pinched wire on either end.

Something I just remembered from a previous thread......There was another fellow on here who had the same problem. It turned out to be the A/C clutch cycling switch on the accumulator shorted to ground. Here's how to test: First unplug the connector from the cycling switch. Replace the blown fuse. Turn on the key and see if the fuse blows when you move the climate control mode selector switch. If the fuse doesn't blow, turn off the key and the mode selector switch. Now install a jumper wire across the connector for the clutch cycling switch. Now turn on the key and then turn on the mode selector switch. If the fuse still doesn't blow, replace the A/C clutch cycling switch and you should be good to go.

Let us know what you find and we can take it from there. Hope this helps.

Skip down to my second paragraph and try that test first. I would reformat this post but I'm on my phone so it's a pain.

You've got a short to ground somewhere. You're going to have to do a visual inspection under the dash and under the hood. Use the wiring diagram I posted to help identify what color wire is what. My guess is there is either a chaffed wire (insulation damaged) or someone has done some work on the wiring and made a mistake. My gut says it could be on either end since 1, the car's had a big block put in it so maybe something got pinched or maybe something didn't get hooked up and burned on exhaust and is now laying on ground, or there was a repair that is a mistake. Or 2, if there is an aftermarket stereo in the dash then the problem could be there. Maybe a wire is broke and shorting on the metal inner structure of the dash. If it were me, I would pull the radio and pull the climate control. I would study the wiring diagram to determine what is getting power when the mode selector is moved and then test each of the wires to identify which one has continuity to ground. Once you know which wire is bad, then you only have to find the bad spot and repair it. Look for a loose or pinched wire on either end.

Something I just remembered from a previous thread......There was another fellow on here who had the same problem. It turned out to be the A/C clutch cycling switch on the accumulator shorted to ground. Here's how to test: First unplug the connector from the cycling switch. Replace the blown fuse. Turn on the key and see if the fuse blows when you move the climate control mode selector switch. If the fuse doesn't blow, turn off the key and the mode selector switch. Now install a jumper wire across the connector for the clutch cycling switch. Now turn on the key and then turn on the mode selector switch. If the fuse still doesn't blow, replace the A/C clutch cycling switch and you should be good to go.

Let us know what you find and we can take it from there. Hope this helps.

Thank you I'll do my best to check it all its had a new stereo and keyless entry and alarm installed so this should be loads of fun ,I appreciate your help

 

[Texas82GP]

Thank you I'll do my best to check it all its had a new stereo and keyless entry and alarm installed so this should be loads of fun ,I appreciate your help

Hopefully it's that low pressure (clutch cycling) switch. That would be an easy fix. If you replace that switch, put the new one on only hand tight!

 

[TURNA]

sounds like maybe there is a bare wire shorting out behind the dash.

take the unit out and and play with it, maybe u will see something spark.

 

[Nathan454]

Blown motor in my 454 big block think I through a main bearing,thinking about the Eagle 496 stroker rotating assembly any input on this build ?

 

[Nathan454]

Ok so the bad news of a knocking motor darkened my door,been doing some research on the 454 to 496 stroker builds,frome what I understand I need to pull the motor,have it cleaned inspected and bored out 60°over inorder to accommodate the new Eagle rotating assembly from summit, what do I need to have the machine shop do to my block ,will they know the proper specs to get my 454 ready for this setup?will my edelbrock performer heads work with this setup or do I need to have them ported,also what type of cam setup would be the best want to keep the rpm range at around 6000,to keep it streetable,anyone out there done this build who can steer me in the right direction?

 

[Opie Knievel]

Here's an article from Super Chevy building a 496 using the Eagle rotating assembly.

http://www.superchevy.com/how-to/project-cars/sucp-0901-496-chevy-big-block-build/

 

[Texas82GP]

PM Bar50 or 565bbchevy. They are both knowledgeable big block guys. They can give good advice. Mine is to find a good machine shop that builds big block Chevy engines and can give you advice on what is needed to be done to meet your goals. Sorry to hear about the trouble with your 454. Keep us updated on the new motor build.

 

[Bar50]

Cut the oil filter apart, if it has metal in it, take it apart. If not, make sure the flex plate is not broken.

You buy the 496 kit to match whatever bore you have or need? Depends on space and time, one might consider grabbing another core block, taking it to the machine shop and leave your car intact until the machine work is finished. Your heads and intake will be perfect.

With aluminum heads, you can easily go up to 10-1 compression and be safe with pump gas. Be realistic in what you want for the car. A mild 496 will make 575+ horsepower easily with your heads and 10-1 compression. Probably 475-500 with 8.5 or 9.0 compression. It really will depend on your budget. You could also consider repairing what you have and adding a larger cam or even upgrade to a hydraulic roller cam.

 

[Nathan454]

Cut the oil filter apart, if it has metal in it, take it apart. If not, make sure the flex plate is not broken.

You buy the 496 kit to match whatever bore you have or need? Depends on space and time, one might consider grabbing another core block, taking it to the machine shop and leave your car intact until the machine work is finished. Your heads and intake will be perfect.

With aluminum heads, you can easily go up to 10-1 compression and be safe with pump gas. Be realistic in what you want for the car. A mild 496 will make 575+ horsepower easily with your heads and 10-1 compression. Probably 475-500 with 8.5 or 9.0 compression. It really will depend on your budget. You could also consider repairing what you have and adding a larger cam or even upgrade to a hydraulic roller cam.

That is great news,thank you for your response, I'm a little heart broken to hear the knock in my engine, it only happens under load,not at idle,someone said it might be a loose converter bolt but I'm unsure,may just want to replace the bearing sets cam and carb and start again with the 454 ,don't know about the 496 build that seems expensive?