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Discussion Starter #1
Here is where I do my work:


Here are my supplies I needed to do the job. (Mostly)


Here is the finished product.




I used an 80Amp fuse and some exotic teflon jacketed wire that is close to a #2 wire. I would rather use a circuit breaker but about everything on this install I already had. Crimp on lugs where ever possible. Battery strap is a Dacor dive tank holddown strap my bro gave me a couple of weeks ago. All fasteners are stainless steel and nylon tywraps.

IMPORTANT:The ground wire attaches to the same location as the original. How does the negative current get to the starter if all grounds go to the chassie? Well there are lots of way and none of them are good for your car!

Through your wheel bearings, CV joints, shifter cables and throttle. You will get arcing and pitting on these surfaces that will cause bearing failure. Perhaps your exhaust if you have metal hangers. If there are smaller ground wired in the harness that go to the engine, they will overheat and can cause a fire or just melt your harness all together.

If you have a dedicated ground from you car chassie to the engine/transaxle, make sure it is large enough to carry the current of the starter and is well grounded. John
 

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so if it doesnt attach where the stock location is i could have problem to start my car ?? im saying that 'cause i've changed the starter last year and in the last month the car didnt start all the time and when i pulled the motor out the car would just start on compression
 

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the long ground cable isn't necessary, why would the current run through your wheel bearings? It will always go the path of least resistance, which would be from whatever ground point on the chassis through the chassis to the neagtive batt cable and to the batt
 

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AustinTXmr2 said:
]IMPORTANT[/B]:The ground wire attaches to the same location as the original. How does the negative current get to the starter if all grounds go to the chassie? Well there are lots of way and none of them are good for your car!

Through your wheel bearings, CV joints, shifter cables and throttle. You will get arcing and pitting on these surfaces that will cause bearing failure. Perhaps your exhaust if you have metal hangers. If there are smaller ground wired in the harness that go to the engine, they will overheat and can cause a fire or just melt your harness all together.

If you have a dedicated ground from you car chassie to the engine/transaxle, make sure it is large enough to carry the current of the starter and is well grounded. John
Have you been taking crazy pills or something?

You don't get arcing without a voltage potential between two parts, and unless something is really wrong, there should be no voltage potential in your wheel bearings, CVs, shifter cables etc!

I can't really remember what was on the 4AGE, but I'm sure there was atleast one large earth running from the transaxle to the chassis, and probably one on the cambelt end of the engine to the chassis also.
 

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Where are you guys running your positive battery cable from the battery to the back of the car? Meaning what route do they take? Pics would be helpful. I ran mine under the car with the throttle cable, but I'm worried if a rock or something cuts the coating off of the wire....
 

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MR2Fast2Catch said:
Where are you guys running your positive battery cable from the battery to the back of the car? Meaning what route do they take? Pics would be helpful. I ran mine under the car with the throttle cable, but I'm worried if a rock or something cuts the coating off of the wire....
For a long exposed wire run like that it should be routed inside of a hose or something that will protect it. Just an idea.
 

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Papo J said:
For a long exposed wire run like that it should be routed inside of a hose or something that will protect it. Just an idea.
Ah, there's an idea. I'll wrap a plastic hose around it and zipe tie them onto the cable.
 

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verno-dub said:
I zip tied my cable to the radiator hard line all the way to the back..
I was afraid to run mine near the radiator piping because I assumed that it got hot.
 

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Discussion Starter #11
Driftin_AW said:
You don't get arcing without a voltage potential between two parts
Driftin_AW, do you always push start your car? ;)

The potential I am concerned about is when you turn your key to the start position. The starter draws lots of current which means lots of potential. If and I say if there is not a proper ground to the engine/transaxle like was there where the original ground was attached (the negative cable is attached to the top of the transaxle) then it will try to find any path. Some of the paths are destructive.

Impressions of the new weight distribution? Non yet, I have been doing chores at the house and look forward to any reason to go to town for something and try it out.
 

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AustinTXmr2 said:
Driftin_AW, do you always push start your car? ;)

The potential I am concerned about is when you turn your key to the start position. The starter draws lots of current which means lots of potential. If and I say if there is not a proper ground to the engine/transaxle like was there where the original ground was attached (the negative cable is attached to the top of the transaxle) then it will try to find any path. Some of the paths are destructive.
Ah now I see what you were getting at - not replacing the ground from engine-chassis when moving the battery. I think you'd be lucky to get it to start if you didn't do that!

Also FWIW a lot of current does not mean lots of potential. If your battery is at 12V then you're not going to get any more than 12V of potential between any two parts of the car (without external devices ;) ).

And for the record, I don't push start my car :p I simply turn the key and the 3sgte easily hums into life :D

 

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I don't agree with the not using a circuit breaker thing.

The reason you don't use it to protect electronic equipment is that they don't act fast enough (or so I believe). On a battery cable a few milliseconds isn't going to do any extra damage. They're very handy because you can just push a button to disconnect the battery (for resetting ECU, doing work on the engine, installing electronic gear etc)
 

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Discussion Starter #16
mk1-1987 said:
so if it doesnt attach where the stock location is i could have problem to start my car ?
You need a heavy wire for the current to get from the negative battery terminal to the starter. As long as there is a heavy cable attached somewhere on the motor/transaxle that allows good ground potential (negative for these cars) you are good.

mk1-1987 said:
the motor out the car would just start on compression
What do you mean by this? Can you expand on this?
 

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i mean that the starter didnt start all the time... sometime it would sometime not at the end it wasnt starting at all...it made only on year that i intall it(rebuild)
 

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Discussion Starter #18
mk1-1987 said:
i mean that the starter didnt start all the time... sometime it would sometime not at the end it wasnt starting at all...it made only on year that i intall it(rebuild)
A bad starter can behave like this, also poor electrical connections. Did you bench test the starter? Remove the starter from the car and hook jumper cables to just the starter/solenoid assy and if it operates every time than the starter is more than likely good. Keep in mind that the starter motor is not designed for continuous duty and will overheat if you run it too long or too often. This test does not take in consideration of the load on the starter motor as it turns the flywheel but I don't know of a good way to do that.

Many autoparts stores will bench test your starter for you also.

If the starter tests good than check your wire and cable connections. Since this has been going on a while I trust you have ruled out a bad battery?
 

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If you have a dedicated ground from you car chassie to the engine/transaxle, make sure it is large enough to carry the current of the starter and is well grounded.
I just used the stock ground cable. I cut off the battery terminal and crimped on a big copper lug, then bolted it to the body, first cleaning off paint unter the lug so I would have a good connection.
 

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Discussion Starter #20
floridatropics said:
Driving impressions?
I just drove to the auto parts store and back. All highway so no curves. The car seems to spin the rear tires a little more :rolleyes: when pulling out on the highway. More testing later on some curves.

BTW, I tywraped all the new battery cables to the hydraulic clutch line and throttle cables under the car and put the plastic underbody covers back on.

John
 
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