ICM's and Coils
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From: Dayton Nevada
ICM's and Coils
Boy if it is not one thing it is another.
Took the car to Reno yesterday for a new windshield install. Run great going in. 50 mile or so.
On the return trip as I was passing through Carson City, headed up the hill toward Mound House it just quit. Tack went to -0- lost all power, Temp at about 210, pulled over to side of road ( HWY 50) tried to start, no good, sounded like it wanted to, then ran a shot spurt and died. got a tow home.
used a test light to check for power, with key on I had power at bat wire connection to ICM, BUT non coming out at other 3 pins.
TODAY, Checked ICM I have 12.83 volts at bat pin on ICM, I have with DVOM 1.30 at trigger side of ICM. Fuel pump is good, checked for spark at Dist. wire to plugs. good. Started car..running now..letting heat up to repeat yeaterday???
Any suggestion???
Took the car to Reno yesterday for a new windshield install. Run great going in. 50 mile or so.
On the return trip as I was passing through Carson City, headed up the hill toward Mound House it just quit. Tack went to -0- lost all power, Temp at about 210, pulled over to side of road ( HWY 50) tried to start, no good, sounded like it wanted to, then ran a shot spurt and died. got a tow home.
used a test light to check for power, with key on I had power at bat wire connection to ICM, BUT non coming out at other 3 pins.
TODAY, Checked ICM I have 12.83 volts at bat pin on ICM, I have with DVOM 1.30 at trigger side of ICM. Fuel pump is good, checked for spark at Dist. wire to plugs. good. Started car..running now..letting heat up to repeat yeaterday???
Any suggestion???
Thread Starter
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Joined: Jun 2012
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From: Dayton Nevada
Thread Starter
Pro
Joined: Jun 2012
Posts: 603
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From: Dayton Nevada
While checking for a problem I found a possible poor connection, I pressed down a connector and it moved so slightly as if to seem it was not secure. I run it today and see what happens.
5/20/18 while checking the distributor I found it was cracked 1/2 way around the coil indent area. any way it is all good now.
5/20/18 while checking the distributor I found it was cracked 1/2 way around the coil indent area. any way it is all good now.
Last edited by Douglas Brown; May 20, 2018 at 09:38 AM.
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From: Dayton Nevada
I had not noticed. Maybe I should pay more attention to the info under members names.
Do all belong or some to a club?
Yesterday I took the vet to Fernley, then to Reno (Summit) pick up a part. back to USA PARKWAY and back to Dayton. NO issue with Ignition fail. Did notice idle RPM a little low while sitting at light on McCarran & Glendale while A/C on, I had to keep the RPM up. And watch the temp rise as well. About 220 I would guess. I turned off the A/C to relief some of the heat.
I had a problem with heat in Las Vegas during the summer months on a 69 E-Type Jag. I had to install a larger Radiator, (2) 16" electric fans, push & pull to get it in an operational range. By that I mean so I could drive it up MT. Charleston with out over heating.
On that subject what do you up here do to reduce the heat?
Do all belong or some to a club?
Yesterday I took the vet to Fernley, then to Reno (Summit) pick up a part. back to USA PARKWAY and back to Dayton. NO issue with Ignition fail. Did notice idle RPM a little low while sitting at light on McCarran & Glendale while A/C on, I had to keep the RPM up. And watch the temp rise as well. About 220 I would guess. I turned off the A/C to relief some of the heat.
I had a problem with heat in Las Vegas during the summer months on a 69 E-Type Jag. I had to install a larger Radiator, (2) 16" electric fans, push & pull to get it in an operational range. By that I mean so I could drive it up MT. Charleston with out over heating.
On that subject what do you up here do to reduce the heat?
Last edited by Douglas Brown; May 4, 2018 at 10:08 AM.
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
The air is less dense when you consider that most of reno is 4500 plus feet. I never had a problem with my stock original l82 with ac because of the factory 3 core radiator and electric fan shroud.
as power went up I installed a stainless steel 10000 rpm flex fan to get rid of the heavy dangerous fan clutch and extended my chin spoiler by 4 inches.
then to a higher GPM aluminum team G water pump.
then to a 1000 hp monster aluminum radiator with dual Spal fans and a Stewart stage 4 water pump over driven to be able to work at lower street rpm and under driven pump pulley for road racing track days
I'mnot in any corvette club. I'm not interested in people bragerts telling everyone that they only have 57 miles on their two year old ZR 1 or Z06 or the other funny one was this 650 hp brand new vette owner complaning to me how he went through $2500 worth of tires in the first 5 months of ownership I can go through a set in one day of road racing
as power went up I installed a stainless steel 10000 rpm flex fan to get rid of the heavy dangerous fan clutch and extended my chin spoiler by 4 inches.
then to a higher GPM aluminum team G water pump.
then to a 1000 hp monster aluminum radiator with dual Spal fans and a Stewart stage 4 water pump over driven to be able to work at lower street rpm and under driven pump pulley for road racing track days
I'mnot in any corvette club. I'm not interested in people bragerts telling everyone that they only have 57 miles on their two year old ZR 1 or Z06 or the other funny one was this 650 hp brand new vette owner complaning to me how he went through $2500 worth of tires in the first 5 months of ownership I can go through a set in one day of road racing
Last edited by gkull; May 4, 2018 at 11:01 AM.
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From: Napa Valley California
My 73, all stock BB, will run at 220 with the a/c on when the air temps go up.
I'll be updating the cooling system and going to a Dewitts, dual fans, Hi performance water pump etc when I do my resto/mod next year.
I'll be updating the cooling system and going to a Dewitts, dual fans, Hi performance water pump etc when I do my resto/mod next year.
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From: Dayton Nevada
When you listed your components, Water pump , Radiator. It got me to thinking about what I had installed. So Looked it up...I have a 3 row Alum, Rad. for 750 HP. core is 17" T x 26 1/4" W total 19" T x 32 1/2" W . Water pump is a EMP Stewart stage 2 #23103 High Vol. I did not think of using an electric fan then...
You finally went to dual elect. fans. Spal ok. Well that worked, Good.
I ordered a shroud and 16" spal fan #2024 with electrical connection.
I'll test drive it up to Tahoe and around the lake to see if that works.
You finally went to dual elect. fans. Spal ok. Well that worked, Good.
I ordered a shroud and 16" spal fan #2024 with electrical connection.
I'll test drive it up to Tahoe and around the lake to see if that works.
Last edited by Douglas Brown; May 11, 2018 at 01:11 PM.
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From: Dayton Nevada
I did not get to Tahoe for that test drive....
Fan therm-o-switch is to kick on at 185, but did not turn on until about 200. Mind you I am reading the dash temp gauge.....15 deg. diff??? ok, so I put a kitchen temp gauge on the radiator and it reads 190,..I let it run....stays at 190...now I take it up the road to mound house.... temp moved to 210??? with A/C on, the dash temp gauge and sits there between the 200 mark and the next mark on the dash gauge. The electric fan is working.
The thermostat is a 195. so I guess it is not that far off.
What operating temps are normal???? I think at this point 200+ is high maybe not???
I would guess that the temp reading at the radiator (kitchen temp gauge) and the dash reading difference is due to the location of the gauges. The fan is keeping the radiator cooler than the motor while the water circulates.
Fan therm-o-switch is to kick on at 185, but did not turn on until about 200. Mind you I am reading the dash temp gauge.....15 deg. diff??? ok, so I put a kitchen temp gauge on the radiator and it reads 190,..I let it run....stays at 190...now I take it up the road to mound house.... temp moved to 210??? with A/C on, the dash temp gauge and sits there between the 200 mark and the next mark on the dash gauge. The electric fan is working.
The thermostat is a 195. so I guess it is not that far off.
What operating temps are normal???? I think at this point 200+ is high maybe not???
I would guess that the temp reading at the radiator (kitchen temp gauge) and the dash reading difference is due to the location of the gauges. The fan is keeping the radiator cooler than the motor while the water circulates.
Last edited by Douglas Brown; May 20, 2018 at 09:54 AM.
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From: Dayton Nevada
220 temp you say w/ A/C on. So this is normal for the Corvette.?
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From: Napa Valley California
I can see 220, sitting in freeway stop and go traffic when the outside temp is 90+, which seems normal for my 73.
I think it's too hot and that's why I'll be improving my cooling system and looking at options to force more air through the radiator at slow speed in traffic and to do what ever I can to circulate more outside air through the engine compartment. Right now little air seems to be able to get in and it seems there is really no place for it to exit once its in there.
When I'm moving down the road whether at 30 or 70 mph my water temp stays around 195-200 degrees.
I remember back in the early 70's overheating seemed to be an issue for many cars when auto manufactures were forced to run things lean, cars were big and heavy, and they included all the options available.
I remember there were warning signs on most interstate grades warning to turn off air conditioning to avoid overheating.
I think it's too hot and that's why I'll be improving my cooling system and looking at options to force more air through the radiator at slow speed in traffic and to do what ever I can to circulate more outside air through the engine compartment. Right now little air seems to be able to get in and it seems there is really no place for it to exit once its in there.
When I'm moving down the road whether at 30 or 70 mph my water temp stays around 195-200 degrees.
I remember back in the early 70's overheating seemed to be an issue for many cars when auto manufactures were forced to run things lean, cars were big and heavy, and they included all the options available.
I remember there were warning signs on most interstate grades warning to turn off air conditioning to avoid overheating.
Thread Starter
Pro
Joined: Jun 2012
Posts: 603
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From: Dayton Nevada
I can see 220, sitting in freeway stop and go traffic when the outside temp is 90+, which seems normal for my 73.
I think it's too hot and that's why I'll be improving my cooling system and looking at options to force more air through the radiator at slow speed in traffic and to do what ever I can to circulate more outside air through the engine compartment. Right now little air seems to be able to get in and it seems there is really no place for it to exit once its in there.
When I'm moving down the road whether at 30 or 70 mph my water temp stays around 195-200 degrees.
I remember back in the early 70's overheating seemed to be an issue for many cars when auto manufactures were forced to run things lean, cars were big and heavy, and they included all the options available.
I remember there were warning signs on most interstate grades warning to turn off air conditioning to avoid overheating.
I think it's too hot and that's why I'll be improving my cooling system and looking at options to force more air through the radiator at slow speed in traffic and to do what ever I can to circulate more outside air through the engine compartment. Right now little air seems to be able to get in and it seems there is really no place for it to exit once its in there.
When I'm moving down the road whether at 30 or 70 mph my water temp stays around 195-200 degrees.
I remember back in the early 70's overheating seemed to be an issue for many cars when auto manufactures were forced to run things lean, cars were big and heavy, and they included all the options available.
I remember there were warning signs on most interstate grades warning to turn off air conditioning to avoid overheating.
I had a 180 in the car and it was sticking intermit. When I checked in boiling water it opened and then the second check it failed to open all the way. which was causing me to blow the ICM's. So I am replacing the therm. with another 180 today.....Thur. I have an appointment for a local mechanic to time the car. He is supposed to be good with the older stuff, he talks like he is, he is older, 55-60yr.
We will see.
Last edited by Douglas Brown; May 22, 2018 at 11:00 AM.
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From: Dayton Nevada
Hey ..how are you doing?
Well, Since last I posted about the ICM, I replaced the Coil, Cap, Rotor, ICM and new condenser unit. I thought it was handled and took wife on ride to brothers for nephews graduation party, Over heated and ICM died as well on freeway in Reno. Replaced the ICM with another brand, and at the wife's insistence I sought out the Mechanic in town I spoke of. I took what I could from our conversation and applied it to what was happening, ie. Timing at this elevation is 5 degrees advanced from stated book figures. so instead of the 4-12 in the book I should be using 16-17 BTDC.. On my way back to the house, 7 miles to town and same to return, It over heated again. ICM did not burn out...I checked the Thermostat in boiling water, it opened at 180, removed and cooled, then returned it to hot water did not open enough. Replaced item. now seems to work fine. Will have him check the timing and check out what I have done, for wife's pace of mind. I can say with out a doubt, Haggerty Ins. has met and exceeded what I thought they should. Two tows no charge.
DB
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
If the old guy Really understands ignition. He would not tell you to arbitrarily bump up the ignition 5 degrees for altitude.
If he doesn't know this you have the wrong guy!
You have to install or get a mechanical advance limiting device. You limit the total mechanical advance to say 22 degrees additional.... hook up the timing light, fire up the motor and hold it at 3500 rpm. Then adjust your dizzy to say 38 degrees total with the Vac advance plugged off. You can then check it at idle, but it falls where it falls because you set it by the mechanical advance total.
38 for stock old iron heads down to 32-33 for modern aluminum with fast burn chambers.
If he doesn't know this you have the wrong guy!
You have to install or get a mechanical advance limiting device. You limit the total mechanical advance to say 22 degrees additional.... hook up the timing light, fire up the motor and hold it at 3500 rpm. Then adjust your dizzy to say 38 degrees total with the Vac advance plugged off. You can then check it at idle, but it falls where it falls because you set it by the mechanical advance total.
38 for stock old iron heads down to 32-33 for modern aluminum with fast burn chambers.
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Joined: Jan 2007
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From: Southern Cal Ca
St. Jude Donor '22
Hey ..how are you doing?
Well, Since last I posted about the ICM, I replaced the Coil, Cap, Rotor, ICM and new condenser unit. I thought it was handled and took wife on ride to brothers for nephews graduation party, Over heated and ICM died as well on freeway in Reno. Replaced the ICM with another brand, and at the wife's insistence I sought out the Mechanic in town I spoke of. I took what I could from our conversation and applied it to what was happening, ie. Timing at this elevation is 5 degrees advanced from stated book figures. so instead of the 4-12 in the book I should be using 16-17 BTDC.. On my way back to the house, 7 miles to town and same to return, It over heated again. ICM did not burn out...I checked the Thermostat in boiling water, it opened at 180, removed and cooled, then returned it to hot water did not open enough. Replaced item. now seems to work fine. Will have him check the timing and check out what I have done, for wife's pace of mind. I can say with out a doubt, Haggerty Ins. has met and exceeded what I thought they should. Two tows no charge.
DB
Well, Since last I posted about the ICM, I replaced the Coil, Cap, Rotor, ICM and new condenser unit. I thought it was handled and took wife on ride to brothers for nephews graduation party, Over heated and ICM died as well on freeway in Reno. Replaced the ICM with another brand, and at the wife's insistence I sought out the Mechanic in town I spoke of. I took what I could from our conversation and applied it to what was happening, ie. Timing at this elevation is 5 degrees advanced from stated book figures. so instead of the 4-12 in the book I should be using 16-17 BTDC.. On my way back to the house, 7 miles to town and same to return, It over heated again. ICM did not burn out...I checked the Thermostat in boiling water, it opened at 180, removed and cooled, then returned it to hot water did not open enough. Replaced item. now seems to work fine. Will have him check the timing and check out what I have done, for wife's pace of mind. I can say with out a doubt, Haggerty Ins. has met and exceeded what I thought they should. Two tows no charge.
DB
i am afraid there is info not posted.
you mention 210 deg at probably high rpm cruise.
now it is over heating.
like i said 210 ain't enough to fry a icm.
overheat may? i say may.
have you been having overheat or temps that seem high?
the hei system gets funky with bad grounds or components running out of the right electrical currents.
care should be taken to use just enough heat sink compound to
make icm contact dist housing.
care when tightening the 2 screws.
so you bought a good icm that took the engine overheating?
now why did it overheat?
sounds like the more you drive the more the engine is starting to
overheat?
failure of head gasket or cracked head?
you are looking to timing as the cause?
hmm, i don't think so.
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Joined: Jun 2012
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From: Dayton Nevada
hey man.
i am afraid there is info not posted.Well I tried to put out what was happening
you mention 210 deg at probably high rpm cruise.Yes the first time the temp was climbing and the gauge read about 210??
now it is over heating.The second time it was OH and getting into the red rea AND the third time it was boiling as I drove into the garage after 14 mile drive. AT that time I changed out the Therostat, which corrected the major heat problem, the electric fan was able to cool the radiator down and shut off and restart as normal
like i said 210 ain't enough to fry a icm.I do not know about that, I only know what happened, BOTH ICMs were ACELL ICM;s and both failed, I replaced it with BW.
overheat may? i say may.
have you been having overheat or temps that seem high? The OH problem just started to happen recently, mind you I just got the car reg. in OCT 2017, at that time I put in a 180 therm. AND a 180 the other day, I have not been able to get further than RENO at any given trip. As I have been road testing it and looking for those items I can not find unless on the road.
the hei system gets funky with bad grounds or components running out of the right electrical currents.Yes, I found that out on the first ICm
care should be taken to use just enough heat sink compound to
make icm contact dist housing.Yes, or it ooozzzes out the side
care when tightening the 2 screws.Just snug enough to hold it in place and ooozzz the stuff out around the edge
so you bought a good icm that took the engine overheating?YES
now why did it overheat?BAD therm
sounds like the more you drive the more the engine is starting to
overheat?Would sound that way, but there are many factors at play, elevation, timing, bad therm, improper anti-freeze mix,and that which you mention next
failure of head gasket or cracked head?NO sign of this
you are looking to timing as the cause?I have always thought timing and carb adjustment as cause, I did not expect therm to be bad since I had just put it in in OCT. I was timing according to book figures, for a 1979 350 6 - 12 deg BTDC depending Evaluation not mentioned, as it was never mention when addressing Vacuum, or Carb springs, jets, meter rods. There are finer aspects to this than I know about. BUT I learn as I go. I would never have thought 16 -17 deg timing w/o the advance hooked up. BUT there it is. SO Bryan has dialed in the timing and carb. HE found that the rear end was missing shims on the trailing arm driver side that should not have been missing, since it was 4 wheel aligned in Oct of 17 Unfortunately for me I tend to believe a professional is to do the best job he can, AS I have done for those I help and not make costly errors. Which is why we do a lot of our own work. as best we can. NOW did the owner do the work or did some hourly empl. who was in a hurry. As has happened to out Mustang in LV when they replaced the clutch with the old one they took out leaving the new one in the box sitting on the table where the owner found it when I called to complain.
hmm, i don't think so.
i am afraid there is info not posted.Well I tried to put out what was happening
you mention 210 deg at probably high rpm cruise.Yes the first time the temp was climbing and the gauge read about 210??
now it is over heating.The second time it was OH and getting into the red rea AND the third time it was boiling as I drove into the garage after 14 mile drive. AT that time I changed out the Therostat, which corrected the major heat problem, the electric fan was able to cool the radiator down and shut off and restart as normal
like i said 210 ain't enough to fry a icm.I do not know about that, I only know what happened, BOTH ICMs were ACELL ICM;s and both failed, I replaced it with BW.
overheat may? i say may.
have you been having overheat or temps that seem high? The OH problem just started to happen recently, mind you I just got the car reg. in OCT 2017, at that time I put in a 180 therm. AND a 180 the other day, I have not been able to get further than RENO at any given trip. As I have been road testing it and looking for those items I can not find unless on the road.
the hei system gets funky with bad grounds or components running out of the right electrical currents.Yes, I found that out on the first ICm
care should be taken to use just enough heat sink compound to
make icm contact dist housing.Yes, or it ooozzzes out the side
care when tightening the 2 screws.Just snug enough to hold it in place and ooozzz the stuff out around the edge
so you bought a good icm that took the engine overheating?YES
now why did it overheat?BAD therm
sounds like the more you drive the more the engine is starting to
overheat?Would sound that way, but there are many factors at play, elevation, timing, bad therm, improper anti-freeze mix,and that which you mention next
failure of head gasket or cracked head?NO sign of this
you are looking to timing as the cause?I have always thought timing and carb adjustment as cause, I did not expect therm to be bad since I had just put it in in OCT. I was timing according to book figures, for a 1979 350 6 - 12 deg BTDC depending Evaluation not mentioned, as it was never mention when addressing Vacuum, or Carb springs, jets, meter rods. There are finer aspects to this than I know about. BUT I learn as I go. I would never have thought 16 -17 deg timing w/o the advance hooked up. BUT there it is. SO Bryan has dialed in the timing and carb. HE found that the rear end was missing shims on the trailing arm driver side that should not have been missing, since it was 4 wheel aligned in Oct of 17 Unfortunately for me I tend to believe a professional is to do the best job he can, AS I have done for those I help and not make costly errors. Which is why we do a lot of our own work. as best we can. NOW did the owner do the work or did some hourly empl. who was in a hurry. As has happened to out Mustang in LV when they replaced the clutch with the old one they took out leaving the new one in the box sitting on the table where the owner found it when I called to complain.
hmm, i don't think so.
Sometimes I would like to live where there are honest shops and persons with knowledge of this car I could get hold of. BUT that's not the way of. I am told Reno has such shops, Sacramento, Las Vegas.
In some cases it is a 50 mile + drive but if I can not go 14 miles with out some thing going wrong, then I is me. And then it comes down to Vary shallow pockets.
CF members are great people, I get good advice, lot of Ideas. Thanks
DB
Last edited by Douglas Brown; May 25, 2018 at 12:45 PM.