New pumps...still overheating??!!! Timing prob.....
Thread Starter
Instructor
Joined: Oct 2001
Posts: 224
Likes: 0
From: Austin TX
New pumps...still overheating??!!! Timing prob.....
Hello all. I replaced my water pump and fuel pump yesterday and was a rather uneventfull day. I did find rust in the steel fuel line that runs between the pump and the carb. The flow doesnt seem to be as well on this pump as the old GM part though. Normally when I had the rad. cap off, I could gas it and you could watch the coolant be sucked down.....This one doesnt do it. The fuel pressure is a lot better until the engine heats up. I'm still getting a BIG bubble when I put the glass filter on to see how its flowing.
I feel the problem is in my timing again. When ever I set it up so it doesnt knock the timing mark reads like -15 degrees.!!!!! :eek: When I set it up for 8 it pings all the h3ll. :mad Anywhere in between there and its either or.....Its vibrating a bit more than it used to as well. Could my dampner slipped?
This engine has 76cc 882 heads so I see no reason for any knocking.....The carb is a 750 Edelbrock.
Any help??
Thanks,
Nicholas :cheers:
[Modified by jaggeedfire, 4:08 PM 4/16/2002]
I feel the problem is in my timing again. When ever I set it up so it doesnt knock the timing mark reads like -15 degrees.!!!!! :eek: When I set it up for 8 it pings all the h3ll. :mad Anywhere in between there and its either or.....Its vibrating a bit more than it used to as well. Could my dampner slipped?
This engine has 76cc 882 heads so I see no reason for any knocking.....The carb is a 750 Edelbrock.
Any help??
Thanks,
Nicholas :cheers:
[Modified by jaggeedfire, 4:08 PM 4/16/2002]
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
Several problems here from your descriptions
Water pump flow - Sounds like you think the flow thru the rad. is less with the new pump. Did you replace the pump with an identical to what you took off? Maybe you had a high flow on there. Was the engine up to temp when you watched the flow (thermostat open)? Remember a lot of air was introduced when you made the change and it will take some time to "burp" all the air out. Get the air out and make sure you are up to temp, then check the flow.
On the fuel pump issue, again was it the same as before. A lot of new ones are rebuilt units and may not be the same. Compare like kind to like kind. Too bad you did not have a fuel pressure measurement from before to compare to.
On the timing, pull plug #1 run the piston to TDC on compression and see where the mark on the balancer is on the pointer. Should be zero. Did you pull the distributor lately? If so, maybe it's not back in right. If your timing light shows -15 degrees to run right, either the balancer or the distributor is off. Water flow, timing, and fuel mixture will all cause you to run hot. Take one thing at a time. Good luck.
Water pump flow - Sounds like you think the flow thru the rad. is less with the new pump. Did you replace the pump with an identical to what you took off? Maybe you had a high flow on there. Was the engine up to temp when you watched the flow (thermostat open)? Remember a lot of air was introduced when you made the change and it will take some time to "burp" all the air out. Get the air out and make sure you are up to temp, then check the flow.
On the fuel pump issue, again was it the same as before. A lot of new ones are rebuilt units and may not be the same. Compare like kind to like kind. Too bad you did not have a fuel pressure measurement from before to compare to.
On the timing, pull plug #1 run the piston to TDC on compression and see where the mark on the balancer is on the pointer. Should be zero. Did you pull the distributor lately? If so, maybe it's not back in right. If your timing light shows -15 degrees to run right, either the balancer or the distributor is off. Water flow, timing, and fuel mixture will all cause you to run hot. Take one thing at a time. Good luck.
Thread Starter
Instructor
Joined: Oct 2001
Posts: 224
Likes: 0
From: Austin TX
Re: New pumps...still overheating??!!! Timing prob..... (bigvette1)
kgraumann--I have been suspectings the thermastat and the fan clutch for most of the heating problems....
bigvette1--thanks for the loads of info. The original I had on it was a GM part. This new one is a reman. from Autozone. I heard that others had good luck with these pieces. I'd be interested in others telling of accounts of other pumps. As far as the fuel pump goes, it is giving me better pressure but Im still getting a 'bubble'. Again..it was not another AC part...but a Master rebuilt pump. Im still not happy with it and wish I would have gone with a Holley or Edelbrock.
Could there be any probs with my ignition to cause these problems? I know that I shouldnt get any knocking for this setup. Could the harmonic of have slipped? What could have happened for my distributor to register so retarded with out taking it out and reseting? The timing mark moved 2 inches from the original spot with out reseting the dist.!!!! :U One more thing...No matter what I do, I cant get teh darn thing to quite running rich. Could this cause a knock??
Thanks for all input!!!!! :cheers:
bigvette1--thanks for the loads of info. The original I had on it was a GM part. This new one is a reman. from Autozone. I heard that others had good luck with these pieces. I'd be interested in others telling of accounts of other pumps. As far as the fuel pump goes, it is giving me better pressure but Im still getting a 'bubble'. Again..it was not another AC part...but a Master rebuilt pump. Im still not happy with it and wish I would have gone with a Holley or Edelbrock.
Could there be any probs with my ignition to cause these problems? I know that I shouldnt get any knocking for this setup. Could the harmonic of have slipped? What could have happened for my distributor to register so retarded with out taking it out and reseting? The timing mark moved 2 inches from the original spot with out reseting the dist.!!!! :U One more thing...No matter what I do, I cant get teh darn thing to quite running rich. Could this cause a knock??
Thanks for all input!!!!! :cheers:
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
Under most circumstances running rich should not cause a knock which is really detonation caused by an over advanced timing condition or too much carbon in the cylinders causing hot spots. With the Edelbrock, has it always run rich or is this a new condition? Did this just start after the pump change ( you said you now have more pressure). Maybe you are blowing fuel by the needle and seat caused by a bad set or too high a float level.
You are right - your setup should not be causing the problems as it is not that radical.
Just for the hell of it, run #1 to TDC on compression and see where the balancer timing mark is in relation to 0 on the timing marker. Should be real close. If not then something has slipped. We want to find out if 0 is still 0.
You are right - your setup should not be causing the problems as it is not that radical.
Just for the hell of it, run #1 to TDC on compression and see where the balancer timing mark is in relation to 0 on the timing marker. Should be real close. If not then something has slipped. We want to find out if 0 is still 0.
Drifting
Joined: Aug 1999
Posts: 1,468
Likes: 1
From: Kirkland WA
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
Bad carbon deposits means too rich. I agree with everyone here you need to check your balancer marks, reset your timing, then adjust your fuel mixture. I know that a lean condition will cause overheating. I assume too rich will do the same.
When I was rebuilding my 65 musting engine (I6), I found out that the timing chain was loose and had skipped a couple teeth. That ended up being the cause of ALL KINDS of problems.
Also, you may want to consider installing an 02 sensor in your exhaust pipes. Helped me dial my mixture in right where it needed to be. Engine temps dropped 20 deg at idle with the right mixture settings.
When I was rebuilding my 65 musting engine (I6), I found out that the timing chain was loose and had skipped a couple teeth. That ended up being the cause of ALL KINDS of problems.
Also, you may want to consider installing an 02 sensor in your exhaust pipes. Helped me dial my mixture in right where it needed to be. Engine temps dropped 20 deg at idle with the right mixture settings.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
I suggest removing the thermostat to test your coolant flow...if you want to put another one in then get a new one (I don't use a thermostat at all).
It sounds like your distributor shaft is loose. Mine is loose and can show almost a 10degrees fluctuation...it causes it to have a lope (like it was a L82). Check it by pulling the dist cap and see if the shaft can move freely...there should be force from the mechanical advance springs holding it in place.
It sounds like you are running very rich...check the float level, when you get on it the fuel may be splashing over the sides.
It sounds like your distributor shaft is loose. Mine is loose and can show almost a 10degrees fluctuation...it causes it to have a lope (like it was a L82). Check it by pulling the dist cap and see if the shaft can move freely...there should be force from the mechanical advance springs holding it in place.
It sounds like you are running very rich...check the float level, when you get on it the fuel may be splashing over the sides.
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Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
Plugs nice and black - you are rich. Take one step at a time or you will not know where you are at.
1. Set the float level to specs or search the posts on Edelbrock 750's and find out what is a good setting for these carbs.
2. Pull and clean the plugs so you know where you are starting from. Set the idle mixture screws to the recommended starting point that Edelbrock recommends or again look at the posts.
3. Run the car for 50 miles or so and pull a couple of plugs on each bank and see there color - should be a toasty brown. If not, clean these plugs off, go to #3
3. Jet the carb down a couple of sizes and run some more miles and check the plugs you checked before.
4. Check the balancer for TDC position and as posted the distributor shaft. You can set the timing to where the car runs fair and get the fuel problem fixed and then fix the timing problem.
Still sounds like several problems. Another point to think about "is the carb still in warranty". I have talked to numerous people and they relate that Edelbrock carbs are either right on or are a royal PITA for running rich that is very hard to control. You might want to consider this. Good luck.
1. Set the float level to specs or search the posts on Edelbrock 750's and find out what is a good setting for these carbs.
2. Pull and clean the plugs so you know where you are starting from. Set the idle mixture screws to the recommended starting point that Edelbrock recommends or again look at the posts.
3. Run the car for 50 miles or so and pull a couple of plugs on each bank and see there color - should be a toasty brown. If not, clean these plugs off, go to #3
3. Jet the carb down a couple of sizes and run some more miles and check the plugs you checked before.
4. Check the balancer for TDC position and as posted the distributor shaft. You can set the timing to where the car runs fair and get the fuel problem fixed and then fix the timing problem.
Still sounds like several problems. Another point to think about "is the carb still in warranty". I have talked to numerous people and they relate that Edelbrock carbs are either right on or are a royal PITA for running rich that is very hard to control. You might want to consider this. Good luck.
Thread Starter
Instructor
Joined: Oct 2001
Posts: 224
Likes: 0
From: Austin TX
Re: New pumps...still overheating??!!! Timing prob..... (Corellian Corvette)
Thanks all for replys....
First Corellian- Considering I rebuilt the engine about 4000 miles back, wounld the chain have slipped already?
Anyway I can remove deposits inside the engine?
Anyone else running an Edelbrock
Whats a good starting mix setting on these?
The engine seems to have a bad misfire or shake at all degrees of timing getting worse with advance. Another sign of slipped harmonic or chain?
Any more tips are appreciated and thanks to all help so far!!!!!!!!!
Hope to get this fixed soon as to this is my only ride for now.
Nicholas
:cheers:
First Corellian- Considering I rebuilt the engine about 4000 miles back, wounld the chain have slipped already?
Anyway I can remove deposits inside the engine?
Anyone else running an Edelbrock
Whats a good starting mix setting on these?
The engine seems to have a bad misfire or shake at all degrees of timing getting worse with advance. Another sign of slipped harmonic or chain?
Any more tips are appreciated and thanks to all help so far!!!!!!!!!
Hope to get this fixed soon as to this is my only ride for now.
Nicholas
:cheers:
Thread Starter
Instructor
Joined: Oct 2001
Posts: 224
Likes: 0
From: Austin TX
Re: New pumps...still overheating??!!! Timing prob..... (bigvette1)
Hey!!! Thanks for all the input....and I found the problem. I twisted my harmonic balancer apart...I was reading 40 degrees off!!!...I got a new one today along with a new clutch for my fan. After finding out the thing had twisted, I set up the car with the proper timing and its running good other than the slight vibration from the balancer. Hoping that these two will cure my problems. Thanks again for all the input!!!!
Nicholas
Nicholas
Melting Slicks
Joined: Apr 1999
Posts: 2,010
Likes: 3
From: Moon Twp. PA USA
Re: New pumps...still overheating??!!! Timing prob..... (jaggeedfire)
Anyway I can remove deposits inside the engine?
Nicholas
:cheers:
