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Maybe a better way would be to add a second fuse block. Jump the white wire from the ignition to the original fuse block to both left sides of a second block, then move the fuel pump white to one right side of the new fuse block and the OD relay to the other right side. Bingo, both are seperately fused in a correct looking fuse block, albeit an additional one. I think the additional fuse block could fit on the firewall just above the steering column. Just a thought.
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Overdrive problems
- Thread starter higgins
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Re: Overdrive problems *DELETED*
Post deleted by Dave Russell
Post deleted by Dave Russell
tahoe healey
Yoda
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Dave, are we talking a 5 amp or a 35 amp fuse? (for the OD)Or somewhere in between. And are you using US rated fuses? I'm sorry but I'm now conFUSEd (Sorry about that pun).
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US rated fuses. It's kind of a trade off between nuisance blowing (5 amp), & taking a little longer to blow if there is trouble (15 amp). There is a short time, probably about 1/2 second, when the fuse has to carry the 20 amp current each time the solenoid operates, the current then normally falls to 2 amps while the solenoid is operated. A 5 amp fuse will work for a while & likely fail eventually from the short time 20 amp overloads. A 15 amp fuse will still protect things if the solenoid sticks & go a lot longer before failing. I prefer a 15 amp, Keoke prefers? adding a 5 amp fuse, or else tacking the circuit on to the existing 35 amp fuse. Not sure what he settled on. If in doubt, do nothing.
In reality, very few of the cars have problems because the circuits in question are not fused. When a problem does occur, it makes a mess of the wiring. The only circuit I feel strongly about adding a fuse to is the tail light- license plate light circuit. This one has caused enough problems to warrent a fuse in the red wire on the back of the dash mounted lighting switch.
Remember, every fuse added is another place for bad connections to occur, or a nuisance fuse blow to happen. The factory arrangement was really a pretty good balance with the exception of the tail - license plate light, which the factory finally corrected on the late BJ8's by mounting an extra fuse in the boot.
D
In reality, very few of the cars have problems because the circuits in question are not fused. When a problem does occur, it makes a mess of the wiring. The only circuit I feel strongly about adding a fuse to is the tail light- license plate light circuit. This one has caused enough problems to warrent a fuse in the red wire on the back of the dash mounted lighting switch.
Remember, every fuse added is another place for bad connections to occur, or a nuisance fuse blow to happen. The factory arrangement was really a pretty good balance with the exception of the tail - license plate light, which the factory finally corrected on the late BJ8's by mounting an extra fuse in the boot.
D
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Re: Overdrive problems *DELETED* *DELETED* *DELETED*
Post deleted by Dave Russell
Post deleted by Dave Russell
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Re: Overdrive problems *DELETED*
Post deleted by Dave Russell
Post deleted by Dave Russell
Keoke
Great Pumpkin
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Then Dave, you should know that a hard short on a relatively long wire is a highly dynamic situation where the short circuit current is rapidly raising the resistnce of the wire, due to its heating, while simultaneously decreasing the current in the circuit to the point where insufficient current reaches the fuse to cause it to blow.---Keoke- /ubbthreads/images/graemlins/yesnod.gif
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Re: Overdrive problems *DELETED*
Post deleted by Dave Russell
Post deleted by Dave Russell
You two have gone over my head on this one. I am not an engineer of any kind, yet alone electrical. However, in 45 years of driving, I have had several dead shorts in the wiring of many vehicles, generally when a wire has been pinched or the insulation has worn off. In every case, where the wire was fused, the fuse blew protecting the circuit. In my dumb youth, my first attempt in fixing such a problem was to install a higher capacity fuse (ok, I didn't know better), but even then the fuse would blow. Bottom line for me, is that if installing an additional fuse to a circuit where AH did not is going to provide some additional insurance against burning up a whole wiring harness or worse the whole car, I am going to do it. An in-line fuse holder is about $3, the fuse 25 cents, and my time isn't worth much these days.
I appreciate the helpful hints offered by all the BCF participants.
I appreciate the helpful hints offered by all the BCF participants.
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[ QUOTE ]
Very simply Dave, a #18 guage wire will not carry 50 amps of current and would have self destructed a long time ago.Simiarly, none of this deals with where to put the fuse,what type to use and what the value should be.---Keoke
[/ QUOTE ]
You are the one who side tracked the discussion with the following baloney:
---------------------
Quote:
"The momentary 19 amp transient will also be gone before they know it occured. Similarly, the variable "T" Time is so short that the energy content in the transient will not cause any heating of the fuse---Keoke"
Quote:
We know all about assumtions Dave,them and the wrong fuse will get you there.--Keoke--
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An 18 gage wire will most certainly carry 50 amps for long enough to blow a 15 amp fuse very quickly & not hurt the wire. Of course the wire would self destruct if the fuse didn't blow. You are the one who said that the wire would get hot, have too much resistance, limit the current, & prevent the fuse from blowing. This statement is just plain un- true. The fuse will blow long before the wire gets hot. I pointed out that even if the wire did get hot instantly, the fuse would still blow.
I don't need any more reminding to stay out your discussions.
D
Very simply Dave, a #18 guage wire will not carry 50 amps of current and would have self destructed a long time ago.Simiarly, none of this deals with where to put the fuse,what type to use and what the value should be.---Keoke
[/ QUOTE ]
You are the one who side tracked the discussion with the following baloney:
---------------------
Quote:
"The momentary 19 amp transient will also be gone before they know it occured. Similarly, the variable "T" Time is so short that the energy content in the transient will not cause any heating of the fuse---Keoke"
Quote:
We know all about assumtions Dave,them and the wrong fuse will get you there.--Keoke--
---------------------
An 18 gage wire will most certainly carry 50 amps for long enough to blow a 15 amp fuse very quickly & not hurt the wire. Of course the wire would self destruct if the fuse didn't blow. You are the one who said that the wire would get hot, have too much resistance, limit the current, & prevent the fuse from blowing. This statement is just plain un- true. The fuse will blow long before the wire gets hot. I pointed out that even if the wire did get hot instantly, the fuse would still blow.
I don't need any more reminding to stay out your discussions.
D
Keoke
Great Pumpkin
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[ QUOTE ]
Maybe a better way would be to add a second fuse block. Jump the white wire from the ignition to the original fuse block to both left sides of a second block, then move the fuel pump white to one right side of the new fuse block and the OD relay to the other right side. Bingo, both are seperately fused in a correct looking fuse block, albeit an additional one. I think the additional fuse block could fit on the firewall just above the steering column. Just a thought.
[/ QUOTE ]
UH! Lets see where are we. OH!!,Yes that is a better method and assures that in the unlikely event that one of those fuses blow none of the existing switched power circuits would be affected.---Keoke- /ubbthreads/images/graemlins/thumbsup.gif
Maybe a better way would be to add a second fuse block. Jump the white wire from the ignition to the original fuse block to both left sides of a second block, then move the fuel pump white to one right side of the new fuse block and the OD relay to the other right side. Bingo, both are seperately fused in a correct looking fuse block, albeit an additional one. I think the additional fuse block could fit on the firewall just above the steering column. Just a thought.
[/ QUOTE ]
UH! Lets see where are we. OH!!,Yes that is a better method and assures that in the unlikely event that one of those fuses blow none of the existing switched power circuits would be affected.---Keoke- /ubbthreads/images/graemlins/thumbsup.gif
Ed_K
Jedi Knight
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I have definite opinions about this subject because of my 28 years in this field, but I will not go into why I think it is a good idea to fuse as many as these circuts as possible based on this experience. I will simply state what I found while going through all of the wiring on my 65 healey on which everything " worked to some degree", when I started on the car last year. The car hasn't been on the road since 1979:
1..The white wire going to the fuel pump was missing about two feet of insulation, it had apparently gotten so hot that the insulation burned all the way off of this wire.
2..The wire that was running next to this one had also gotten hot probably being heated by the problem with the white wire being so close. It was missing a few inches of insulation but the insolation was expanded and loose for a foot on either side of the missing insolation. Both of these wires were damaged along the side of the front of the transmission tunnel cover and I almost didn't notice the problem before installing the tunnel cover.
3..At some time in the past, my dad had to repair the wire going to the OD soleniod as it also had gotten hot, melted the insolation off, and then shorted.
4..Two of the wires going to the overdrive relay were repaired by my dad.
5..The wires on the back of the O/D dash switch had been so hot at some point in time that all of the insolation was loose and had " backed away " from the connectors that attached to the O/D dash switch leaving bare wire exposed behind the dash.
6..The wire going to the fuel sender on the gas tank had the insulation scrubed off at several points.
7..The red wire going to the rear lights had been repaired by my dad after it had shorted out in the past.
8..Close inspection of all of the dash board switches and the ignition switch showed the effects of excessive heat. The terminal lugs were loose because the plastic had gotten hot enough to allow them free movement around their mechanical mounting points. The reason why I took a close look at these and then replaced them all was that they all didn't exactly work right. You had to get the switch in the " sweet spot " before what ever it controled would turn on.
9..Also of note was that my dad had repaired a few pieces of wire that had " failed " going to the headlights.
....I could go on about the poor condition of most of the lucor connectors, some where split and not exerting enough force to make a good connections, others were simply corroded. I wound up replacing most of these with modern connectors as I am not looking to keep the car completely original in areas such as these that were of an extremely poor original design and then implemented with a poor choice of materials.
..... Draw your own conclusion if it would be worth a little time and money to fuse at least SOME of these circuts so this can not happen to your your car, unless it has happened to your car already but you don't know it yet !
1..The white wire going to the fuel pump was missing about two feet of insulation, it had apparently gotten so hot that the insulation burned all the way off of this wire.
2..The wire that was running next to this one had also gotten hot probably being heated by the problem with the white wire being so close. It was missing a few inches of insulation but the insolation was expanded and loose for a foot on either side of the missing insolation. Both of these wires were damaged along the side of the front of the transmission tunnel cover and I almost didn't notice the problem before installing the tunnel cover.
3..At some time in the past, my dad had to repair the wire going to the OD soleniod as it also had gotten hot, melted the insolation off, and then shorted.
4..Two of the wires going to the overdrive relay were repaired by my dad.
5..The wires on the back of the O/D dash switch had been so hot at some point in time that all of the insolation was loose and had " backed away " from the connectors that attached to the O/D dash switch leaving bare wire exposed behind the dash.
6..The wire going to the fuel sender on the gas tank had the insulation scrubed off at several points.
7..The red wire going to the rear lights had been repaired by my dad after it had shorted out in the past.
8..Close inspection of all of the dash board switches and the ignition switch showed the effects of excessive heat. The terminal lugs were loose because the plastic had gotten hot enough to allow them free movement around their mechanical mounting points. The reason why I took a close look at these and then replaced them all was that they all didn't exactly work right. You had to get the switch in the " sweet spot " before what ever it controled would turn on.
9..Also of note was that my dad had repaired a few pieces of wire that had " failed " going to the headlights.
....I could go on about the poor condition of most of the lucor connectors, some where split and not exerting enough force to make a good connections, others were simply corroded. I wound up replacing most of these with modern connectors as I am not looking to keep the car completely original in areas such as these that were of an extremely poor original design and then implemented with a poor choice of materials.
..... Draw your own conclusion if it would be worth a little time and money to fuse at least SOME of these circuts so this can not happen to your your car, unless it has happened to your car already but you don't know it yet !
Keoke
Great Pumpkin
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Well ED_K, with a background model like that it is easy to see why one would implement a broad set of solutions.On the otherhand, if we could look at and statistically total the wiring circuit failures in all the cars produced we probably would end up with a smaller group of critical circuits that need additional protection.For your #6 item,I added,"ISOLATION", an additional plastic conduit over the harness and then immobolized it by installing a piece of carboard in the void between the existing tank strap paper isolators and extending it strap to strap.Directly over the tank I have a 1/2" thick piece of carpet foam padding then the carpet goes down. I do believe however,that an ounce of preventon is worth a pound of care--Fwiw---Keoke
GregW
Yoda
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Hi Ed,
My car has almost 90,000 miles on it, and some of those were pretty harsh. My dad used to haul his 16’ racing boat with the Healey. That included backing the car down a ramp into the water to get the boat onto the trailer. He used to drive it in snow and mud as well. When I pulled the harness out for the restoration, it was in surprisingly good condition. None of insulation had worn or melted away. The one thing I did note was corrosion on the wires had crept several inches up under the insulation from the connector ends. Having said that, I made a new fuse block with ten fuses and have a few in-line under the dash. If you haven’t seen the “ Using inline fuses ” thread you should check it out. There are a couple photos of custom fuse blocks that can get the creative juices flowing. /ubbthreads/images/graemlins/smile.gif
My car has almost 90,000 miles on it, and some of those were pretty harsh. My dad used to haul his 16’ racing boat with the Healey. That included backing the car down a ramp into the water to get the boat onto the trailer. He used to drive it in snow and mud as well. When I pulled the harness out for the restoration, it was in surprisingly good condition. None of insulation had worn or melted away. The one thing I did note was corrosion on the wires had crept several inches up under the insulation from the connector ends. Having said that, I made a new fuse block with ten fuses and have a few in-line under the dash. If you haven’t seen the “ Using inline fuses ” thread you should check it out. There are a couple photos of custom fuse blocks that can get the creative juices flowing. /ubbthreads/images/graemlins/smile.gif
VelodromeRacer
Jedi Trainee
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Back to overdirve issues that I suffered through. Thanks for all of the advice on the low pressure issue. With no visible leaks, and only 200 psi, we looked internally and found a scratch in the housing for the accumulator...or pump. we soldered it well, put it together and bang, right up to 450 psi...it works like a dream now! It was a very slight scratch, but enough to allow pressure blow-by.