Still hard starting when engine hot
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Joined: Jan 2009
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From: anchorage ak
You think? I'm not disagreeing cause I've seen alot of things that don't make sense, but I haven't yet seen a cracked cap cause the starter to drag, i guess when it gets warm and the Crack opens, but that's about as far as I can think it through. Can you elaborate some? I figure if he retards it 10 degrees and it starts normal then the first thing to do would be to check the mechanical advance.
Safety Car
Joined: Jan 2009
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From: New York
You think? I'm not disagreeing cause I've seen alot of things that don't make sense, but I haven't yet seen a cracked cap cause the starter to drag, i guess when it gets warm and the Crack opens, but that's about as far as I can think it through. Can you elaborate some? I figure if he retards it 10 degrees and it starts normal then the first thing to do would be to check the mechanical advance.
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
samdjr74,
What is the condition of the harmonic balancer? Is it the original to the engine? If it is then how many miles? Balancers get old and the rubber insulators between the center hub and the outside ring wear out and they can slip or walk off. If yours is worn and it slipped, the timing marks are no longer trustworthy. This is what a couple of the forum members are referring to.
Ive had headers on all my hot rods, street rods and my 80 vette. Heat from headers causing a slow turning starter was never a problem, it's always a timing, electrical wiring, solenoid, bad battery, etc..
Also, since you connected a separate 12v line to the starter and it still turned over slowly, we need to take a look back at things that have already been checked off.
What is the condition of the harmonic balancer? Is it the original to the engine? If it is then how many miles? Balancers get old and the rubber insulators between the center hub and the outside ring wear out and they can slip or walk off. If yours is worn and it slipped, the timing marks are no longer trustworthy. This is what a couple of the forum members are referring to.
Ive had headers on all my hot rods, street rods and my 80 vette. Heat from headers causing a slow turning starter was never a problem, it's always a timing, electrical wiring, solenoid, bad battery, etc..
Also, since you connected a separate 12v line to the starter and it still turned over slowly, we need to take a look back at things that have already been checked off.
Last edited by BlackC3vette; Jun 18, 2016 at 08:35 PM. Reason: memory issues
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
It's the original to the car, or at least I think it is. As far as the condition, it's rusty but looks solid, I'm not sure how to check it our properly.
samdjr74,
What is the condition of the harmonic balancer? Is it the original to the engine? If it is then how many miles? Balancers get old and the rubber insulators between the center hub and the outside ring wear out and they can slip or walk off. If yours is worn and it slipped, the timing marks are no longer trustworthy. This is what a couple of the forum members are referring to.
Ive had headers on all my hot rods, street rods and my 80 vette. Heat from headers causing a slow turning starter was never a problem, it's always a timing, electrical wiring, solenoid, bad battery, etc..
Also, since you connected a separate 12v line to the starter and it still turned over slowly, we need to take a look back at things that have already been checked off.
What is the condition of the harmonic balancer? Is it the original to the engine? If it is then how many miles? Balancers get old and the rubber insulators between the center hub and the outside ring wear out and they can slip or walk off. If yours is worn and it slipped, the timing marks are no longer trustworthy. This is what a couple of the forum members are referring to.
Ive had headers on all my hot rods, street rods and my 80 vette. Heat from headers causing a slow turning starter was never a problem, it's always a timing, electrical wiring, solenoid, bad battery, etc..
Also, since you connected a separate 12v line to the starter and it still turned over slowly, we need to take a look back at things that have already been checked off.
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
So for tomorrow, here's what I'm planning, let me know if this is right.
Take the car out, get it up to temp. Don't turn it off but retard the timing by 10 degrees. Shut it off and see if it starts normally.
Anything else I should test/check while doing this? I'll check the cap for any damage but I think it's ok, I can get a new cap and rotor tomorrow if needed.
Take the car out, get it up to temp. Don't turn it off but retard the timing by 10 degrees. Shut it off and see if it starts normally.
Anything else I should test/check while doing this? I'll check the cap for any damage but I think it's ok, I can get a new cap and rotor tomorrow if needed.
Pro
Joined: Jun 2016
Posts: 567
Likes: 82
From: Auckland
All this really says is that it is old. So it could have slipped. Easiest way to tell is to use a piston stop in the #1 cylinder and rotate the engine by hand until it stops and mark the balance. Then rotate it back the other way until it stops and put another mark on it. Then check if the TDC mark on the balance is centered between the two marks you made. If it isn't centered than the balance has slipped.
Safety Car
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From: anchorage ak
If it were cross sparking. Wouldn't it backfire and if started, it wouldn't run right, right,? So with the unplugged ignition wire, it cranks normally, which tells me that it's advanced, either slipped balancer ring or stuck mechanicals. Either way, try retarding the timing 10 degrees before shutting it off after it being hot, if it a arts normally then we can work forward from that point.
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
So for tomorrow, here's what I'm planning, let me know if this is right.
Take the car out, get it up to temp. Don't turn it off but retard the timing by 10 degrees. Shut it off and see if it starts normally.
Anything else I should test/check while doing this? I'll check the cap for any damage but I think it's ok, I can get a new cap and rotor tomorrow if needed.
Take the car out, get it up to temp. Don't turn it off but retard the timing by 10 degrees. Shut it off and see if it starts normally.
Anything else I should test/check while doing this? I'll check the cap for any damage but I think it's ok, I can get a new cap and rotor tomorrow if needed.
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Advanced
Joined: Jun 2014
Posts: 74
Likes: 15
From: Americus GA
You have checked everything except for a couple of items. Fuel pump and fuel return system. If the fuel pump bypass orifice or line is plugged. Fuel pump should have three hoses attached. Quardrajet float level. The float level can be checked without removing the top of the carb.
Safety Car
Joined: Jan 2009
Posts: 4,000
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From: New York
He has already moved the timing back and according to him it cranks the same and runs with no power at all. ( I am summing up his words LOL )
I also see he changed the cap . Could have 5 and 7 on wrong.
Pull # one plug place finger over spark plug hole , have someone bump motor over until you feel your finger is going to be blown off the hole.
Now look at the timing marks . If it slipped it will be way off, if not it will have stopped somewhere before tdc ...
Now pull cap and look at rotor , is it pointing in the direction of the number one wire ?
I also see he changed the cap . Could have 5 and 7 on wrong.
Pull # one plug place finger over spark plug hole , have someone bump motor over until you feel your finger is going to be blown off the hole.
Now look at the timing marks . If it slipped it will be way off, if not it will have stopped somewhere before tdc ...
Now pull cap and look at rotor , is it pointing in the direction of the number one wire ?
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
He has already moved the timing back and according to him it cranks the same and runs with no power at all. ( I am summing up his words LOL )
I also see he changed the cap . Could have 5 and 7 on wrong.
Pull # one plug place finger over spark plug hole , have someone bump motor over until you feel your finger is going to be blown off the hole.
Now look at the timing marks . If it slipped it will be way off, if not it will have stopped somewhere before tdc ...
Now pull cap and look at rotor , is it pointing in the direction of the number one wire ?
I also see he changed the cap . Could have 5 and 7 on wrong.
Pull # one plug place finger over spark plug hole , have someone bump motor over until you feel your finger is going to be blown off the hole.
Now look at the timing marks . If it slipped it will be way off, if not it will have stopped somewhere before tdc ...
Now pull cap and look at rotor , is it pointing in the direction of the number one wire ?
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
Update, I retarded the timing by about 10 to 12 degrees when the engine was hot. I let it sit for 10 to 15 minutes and it actually started right up. However, with the timing this far behind it won't run to well, bogs down a lot.
Safety Car
Joined: Jan 2009
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From: anchorage ak
Get it hot, shut it off, pull the vaccum advance line and cap the port supplies the vaccum, see if she starts, if that makes no difference, pull the cap and just as 75 said, twist the rotor, if it dies not move freely minus the spring tention you have issues there, remove the rotor and take a picture of you mechanical advance to post, while your there twist the mechanism back and forth to see if it not bound up and would move freely if it weren't for the springs. We're about there now...
Last edited by bluedawg; Jun 19, 2016 at 02:06 PM.
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
Hi all,
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
Hi all,
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
Safety Car
Joined: Jan 2009
Posts: 3,736
Likes: 56
From: anchorage ak
Hi all,
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
I adjusted the timing a little more and the car's at a point where it starts correctly and doesn't bog down but the timing is reading really off, like 30 degrees so I'm guessing you guys hit it on the head, my balancer may have shifted. What I'm going to do is take it out again tomorrow or Tuesday if I can a change and see if I'm getting the same results. If not, I will run the next set of tests but so far so good.
I'm not completely out of the woods and I do plan on getting a new motor within the next year or so, that means I don't want to dump a bunch of money into this one. As I said, it runs but it's old, and tired. Not high miles but it's from 1980 and a new GM crate motor should be trouble free for years to come.
Again, thanks for all the help, you guys showed me where to look and I learned a lot of timing, ignition and trouble shooting.
I'll keep you posted with the next set of tests.
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
Thread Starter
Racer
Joined: Aug 2009
Posts: 483
Likes: 3
From: Pequannock NJ
Hello all,
I just wanted to followup on this and let everyone know the issue has been resolved. My balancer hasn't slipped, the problem was my timing light. Once I got a new light and verified piston #1 was at TDC I was able to get see what my true timing was running at. When I thought it was at 12 it was actually at 19 degrees. The problem is my timing light is junk and a mechanic friend of mine brought over his, we now have it set to 11 degrees and it starts right up every time. Thanks again for all the help on this!
I just wanted to followup on this and let everyone know the issue has been resolved. My balancer hasn't slipped, the problem was my timing light. Once I got a new light and verified piston #1 was at TDC I was able to get see what my true timing was running at. When I thought it was at 12 it was actually at 19 degrees. The problem is my timing light is junk and a mechanic friend of mine brought over his, we now have it set to 11 degrees and it starts right up every time. Thanks again for all the help on this!