FOUND SOLUTION, DID NOT BLOW UP MY 91 LX

[mustangsquared]

Ok for those not following my cars "issues" this is what was wrong:

1. surge demon
2. burning starter relays faster then gas
3. running hot
4. 3G alt not putting out (no not that type of out)

while all those problems were caused by 2 bad cables...pos battery to starter relay and the neg battery to block. Replaced both of them and all is well. I feel like such a Jak@ss after fighting with it for a month. Hope this saves someone else alot of trouble shooting. Thanks to everyone for their help.

 

[tmoss]

If your using the aluminum timing cover to ground your neg battery terminal, I suggest you move it to the head. When I pulled my neg battery bolt out of the cover last winter durting the h/c/i tweak, most of the threads in the cover had corroded away from the bolt. It's called galvanic corrosion and it occurs when two dissimilar metals (steel bolt - aluminum cover) come into contact with each other.

 

[BlackGT89]

If your using the aluminum timing cover to ground your neg battery terminal, I suggest you move it to the head. When I pulled my neg battery bolt out of the cover last winter durting the h/c/i tweak, most of the threads in the cover had corroded away from the bolt. It's called galvanic corrosion and it occurs when two dissimilar metals (steel bolt - aluminum cover) come into contact with each other.

I completely agree, this ground is the pits. I pulled up in my driveway a while back and my car went completely dead. I cleaned this ground and no more problems (not the first time I've had trouble with this ground). To complicate things, there is an aluminum strap that supports a cable going under the engine that also occupies this spot. I rearranged the hook up so that the ground wire would be next to the timing cover instead of the aluminum support bracket. No doubt a dedicated ground going to cast iron would be a better way to go.

 

[Michael Yount]

There's actually a third component necessary for galvanic corrosion to occur - the presence of an electrolyte.

Galvanic corrosion (also called ' dissimilar metal corrosion' or wrongly 'electrolysis') refers to corrosion damage induced when two dissimilar materials are coupled in a corrosive electrolyte. It occurs when two (or more) dissimilar metals are brought into electrical contact under water. When a galvanic couple forms, one of the metals in the couple becomes the anode and corrodes faster than it would all by itself, while the other becomes the cathode and corrodes slower than it would alone. Either (or both) metal in the couple may or may not corrode by itself (themselves) in seawater. When contact with a dissimilar metal is made, however, the self corrosion rates will change - corrosion of anode will accelerate, corrosion of the cathode will slow down or even stop. This characteristic is used to protect some things - like steel pipelines in the ground. By attaching a 'sacrificial' anode of the right material, the anode corrodes instead of the pipeline.

It's really a problem for things like water pump bolts that are steel, resting on aluminum and protruding into the coolant passages, or access to coolant occurs through tiny leaks in the gasket surface. This is the primary reason that so many people have failed water pump bolts after sitting there for 15 years slowly corroding.

Without the electrolyte, the dissimilar metal corrosion can still occur, but at slower rates. Keep in mind, even if you bolt the steel bolt to the cast iron block or head, the wire is copper - and the dissimilar metal condition still exists. The wire will become the anode instead of the bolt.

 

[tmoss]

The farther apart the two metals are on the periodic table, the faster they will corrode. The copper-to-iron exchange will be much slower. My bolt had probably never been removed.

 

[mustangsquared]

I moved the cable under the bracket (closer to what ever it attachs to). I also upgrade teh POS cable to 2 guage and the neg to 4 (could not find a 2 gauge that was long enough).

 

[Michael Yount]

I've heard if you just fold the periodic table/chart up so that they're closer together, and keep it in your glove box, that will slow the rate.

 

[mustangsquared]

MY...I swear between your knowledge and your humor I never know what to expect until I completely read your posts...

 

[UMDSmith]

Its an old boating trick as well, thats why you attach that seperate sacrificial peice on the bottom of the prop housing assembly. It corrodes and allows the prop housing to resist corrosion. I can't remember what it is called off hand, but normally you have to swap them out once every 2 or so years.

 

[Michael Yount]

tmoss is the man - I'd forgotten about my periodic table. Athough, it is nice to know that there's a reason stuff can apparently just 'sit there' and corrode.

 

[tmoss]

Its an old boating trick as well, thats why you attach that seperate sacrificial peice on the bottom of the prop housing assembly. It corrodes and allows the prop housing to resist corrosion. I can't remember what it is called off hand, but normally you have to swap them out once every 2 or so years.

It's normally called the "sacrificial anode"

 

[nito88stang]

If your using the aluminum timing cover to ground your neg battery terminal, I suggest you move it to the head. When I pulled my neg battery bolt out of the cover last winter durting the h/c/i tweak, most of the threads in the cover had corroded away from the bolt. It's called galvanic corrosion and it occurs when two dissimilar metals (steel bolt - aluminum cover) come into contact with each other.

What if you're using aluminum heads ?

 

[cdog301]

bolt

Tmoss and M Yount you guys rock this is what stang net should be about! people helping people with their ponies

 

[Michael Yount]

Galvanic corrosion doesn't discriminate. But remember - this doesn't happen over night - takes time.

 

[HISSIN50]

first off, great thread! now bear with me and my toddler-level of intellect.

Michael and Tom, does this galvanic corrosion relate to why you (Michael, i know you do; Tom, I'm not sure if you do) run a ground strap on the cooling system coils? i might guess that the ground removes any charge in the 'electrolyte (or coolant, if that is correct to say. remember im stupid), so as to slow the galvanic corrosion..??

and the sacrificial anodes that Tom mentioned - i think they make those for cooling systems as well. correct? good idea to run one or not worth it? I've read of them, but never knew anyone who had real world experience (or theory that was unbiased).

when i grow up, i wanna be like Michael and Tom.

 

[Michael Yount]

Yup - even if you run distilled water, minerals from the cooling system components leach into the coolant (and other trace minerals in the antifreeze) causing even the cleanest/best kept coolants to act like electrolyte. Anything you can do to minimize that serving to act with various metals and forming a 'battery' of sorts will slow the rate of corrosion. I think this is the main cause of heater core failure - the copper core, the iron/aluminum blocks/heads, and coolant acting as electrolyte causes the copper core to lose metal that gets deposited inside the block/heads. Eventually enough metal gets lost from the core that a leak springs. You can't eliminate it completely, but you can slow it to manageable levels. You start to realize how problematic this is when vehicles live near the coast and humid/salt laden air circulates around things. Talk about electrolyte....

Sorry about the 'yup' - pressed the wrong button at the wrong time. If only they'd make a computer that does what I want it to instead of what I tell it to...

 

[tmoss]

What if you're using aluminum heads ?

Try to find a place on the iron block then.

Edit: Or go to a electrical supply house and buy a tube of "no-ox", a black anticorrosion compound that will stop the corrosion if you use it on the threads. I use it on my battery posts too and it eleiminates corrosion there too. This compound can be used in any connection that may have the potential for corrosion.

 

[tmoss]

One way to check the coolant system is to remove the cap from the radiator while the engine is cool, put the red lead from a voltmeter on a very low voltage range (0-5v or mv scale if you have one) and stick the tip in the coolant at the filler neck, then put the black lead on a good ground. Run the engine and if you see over .25-.5v (250-500mv), then there is a chance your anti-corrosion compounds in your antifreeze are used up - change the water and antifreeze (and use distilled water). I don't run a ground strap to my radiator because I change my antifreeze each year.

 

[HISSIN50]

Michael, thanks for the thorough response (i was logging off this a.m. and saw the "Yup." i thought, 'Wow, Michael is direct in the morning before coffee.' ).

great info from both of ya (Michael and Tom). ill pick up some no-ox too. sounds like good stuff to have on hand. then i gotta go check the mV's in the system.

as long as we are kicking theory stuff around: if one was to run just pure distilled water (which is deionized, i think), in theory, would the deionized water try to pull metal out of the system? (something along the lines of balancing itself)? my faint recollection of this type of stuff tells me it might be true in theory, but practically speaking, is not much of an issue.

ive always been a little curious....

 

[Michael Yount]

I don't know - I always run distilled; it's cheap, and I figure I should try to keep mineralsout of the system any way I can. They might end up as a heat transfer reducing deposit or contribute to electron transfer, and maybe distilled helps reduce that.