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Ok to use "incorrect" battery while working on car?

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XC92

Proven Member
1,570
357
Jul 22, 2020
Queens, New_York
My '92 Talon's been stored for several years due to various issues I put off dealing with and I've only recently started working on it, so it needs a new battery.

I know which one I intend to get, an Interstate Group 86 from Costco, for $100 (local auto stores want $120 or more for the same type of battery and I prefer to deal with Costco for their no questions asked return/replace policy), but my local ones are out of stock and have to order it, and it'll take several weeks.

In the meantime, I need a battery to work on various things with the car. Is it ok to use basically any SLA 12V auto battery that has enough amps to get the car started and running, that fits in the battery box for this, with the hood up so no clearance issues? What about test drives, if clearance isn't an issue?

Hell, can I even use a LiOn power bank jump starter if I just want to turn the engine over briefly, say for a compression check, or is that dangerous for the car or jump starter's electronics?

How about an SLA-based jump starter? I have both kinds. I assume that if this is ok, it's only ok for a few seconds, not to actually run the car with the plugs in, right?
 
It won't hurt anything. 12 volts is 12 volts. The car doesn't care what type or size of battery it comes from. Your only damage risk would be hooking it up backwards and then something could fry. This is easy to do if you not paying attention as different size group batteries may have the terminals opposite.
 
Ok, thanks. It's just temporary until the proper battery I order arrives so I don't have to wait on it doing other things that require a battery.
 
I forgot to add/answer your question on the jumper packs.

You can use those as well with no issues. The SLA pack you could even run the car on for while to check stuff. I am not sure if you would want to run the engine for any significant period of time with a lithium jumper pack... The car will be fine but my concern would be possible damage to the jumper pack. Lithium batteries are very picky about how they are charged and I'm not sure the alternator feeding 14 volts straight to the jumper pack would be good for it. But for just cranking the engine to do a compression check or starting to check oil psi and quick things you'd be ok.
 
The SLA pack you could even run the car on for a while to check stuff.
Yes.

I am not sure if you would want to run the engine for any significant period of time with a lithium jumper pack.

I'm not too sure about this either.
I've looked for this in a few of the jumper pack user guides and haven't found any warnings about it.
But I'm suspicious about it because if your pack is made from Li Ion or Li Po cells, the fully charged output voltage is likely to be about 16 volts, which is a lot more than your alternator puts out. Or it might only be about 12.3 volts, which is a lot less than your alternator puts out. Depends on whether they are using 4 cells or 3 cells in the pack.
If the pack is made from LiFePO4 cells you are in good shape. Because then the fully charged output voltage would be about 13.6 volts which is almost identical to what our alternators put out.
I don't have one of these things yet but I've shopped a bit, and looked at some of the user manuals. Haven't found a single one yet that states in writing what the maximum output voltage is at full charge. But I have found a few that say they use Lithium iron phosphate cells (LiFePO4). I would buy one of those if I bought one.

I've only ever had one used on my car one time. The honors were done by Lucas English himself, with me in the car pushing the starter button. I noticed that he pulled the clips off the battery immediately after the engine fired. Don't know if that means anything. He might have just been in a hurry LOL
Fully charged (maximum) voltage per cell for various types of Li Ion batteries:
Li Ion: 4.1 v
Li Polymer: 4.2 v
LiFePO4: 3.4 v
The jumper packs will have 4 cells in series, as far as I know, unless there are people making 3 cell LiPoly jumper packs.
 
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Yes.



I'm not too sure about this either.
I've looked for this in a few of the jumper pack user guides and haven't found any warnings about it.
But I'm suspicious about it because if your pack is made from Li Ion or Li Po cells, the fully charged output voltage is likely to be about 16 volts, which is a lot more than your alternator puts out. Or it might only be about 12.3 volts, which is a lot less than your alternator puts out. Depends on whether they are using 4 cells or 3 cells in the pack.
If the pack is made from LiFePO4 cells you are in good shape. Because then the fully charged output voltage would be about 13.6 volts which is almost identical to what our alternators put out.
I don't have one of these things yet but I've shopped a bit, and looked at some of the user manuals. Haven't found a single one yet that states in writing what the maximum output voltage is at full charge. But I have found a few that say they use Lithium iron phosphate cells (LiFePO4). I would buy one of those if I bought one.

I've only ever had one used on my car one time. The honors were done by Lucas English himself, with me in the car pushing the starter button. I noticed that he pulled the clips off the battery immediately after the engine fired. Don't know if that means anything. He might have just been in a hurry LOL
Fully charged (maximum) voltage per cell for various types of Li Ion batteries:
Li Ion: 4.1 v
Li Polymer: 4.2 v
LiFePO4: 3.4 v
The jumper packs will have 4 cells in series, as far as I know, unless there are people making 3 cell LiPoly jumper packs.
We use jump packs all day long in my shop. They all put out about 14.6 full charged and around 13 when they are low.
 
Thanks all. I'll borrow one of our other cars' batteries for now until I get the Costco one. I also have to figure out how to safely dispose of 3-4 gallons of 3-4 year old gas before I can fire up the engine anyway. At least I was able to turn the engine over manually today via the front crankshaft bolt, after squirting some Marvel Mystery Oil into the plug holes.

Btw is it normal for the engine resistance to being turned manually to vary from hard to easy as the engine turns, with all 4 plugs out? I initially turned it counterclockwise by accident a turn or two. How bad is that?
 
Well, I burn up all my old gas by pouring it into my 1990 Toyota Corolla. That thing runs no matter what I do to it. LOL
Seriously I don't know what to do with really really old gas either. But I have put up to 2 year old gas in my Toyota. Which has 315,000 miles on it.

Yes the engine resistance to turning is bumpy, because of the cam lobes. Every time a cam lobe starts to open a valve, it gets harder to turn.

Turning backwards - how bad is it - seems to me people have had different experiences with that. The Factory Service Manual does say not to turn it counterclockwise. It might depend on whether your timing belt is properly tensioned or not. How many miles are on this car? I think I have read of this coming up when a person parks on a hill nose up with a bad emergency brake and leaves the gear lever in 1st to keep the car from rolling backwards.

If you have a clear top cover over the timing belt, then it is pretty easy to check the marks to make sure they line up the way they are supposed to.
If you have the stock top cover there, probably some people will tell you to take it off so you can check the marks.
I'll tell you though, taking the top cover off, even though it is pretty easy, is not to be taken lightly. When that cover is off, it is easy to just stupidly drop a bolt or washer or whatever right into the space there where the timing belt is. So be real careful about that. I mean, if you drop something in there you can't just leave it there, I don't think. You just about have to take the rest of the cover off to get that dropped thing out of there.
 
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Thanks all. I'll borrow one of our other cars' batteries for now until I get the Costco one. I also have to figure out how to safely dispose of 3-4 gallons of 3-4 year old gas before I can fire up the engine anyway. At least I was able to turn the engine over manually today via the front crankshaft bolt, after squirting some Marvel Mystery Oil into the plug holes.

Btw is it normal for the engine resistance to being turned manually to vary from hard to easy as the engine turns, with all 4 plugs out? I initially turned it counterclockwise by accident a turn or two. How bad is that?
It won't hurt anything unless you jumped time. Check your marks again. No in my experience it shouldn't vary but turning by hand you could just be experiencing rings against the walls especially after sitting this long.

In my local municipality we have hazmat drop-off included with the city water bill so I can take stiff there for disposal
 
Well, at least it turned, so it's not rusted and seized. Next step is starting the car, or at least turning it over with the starter with the plugs out for a compression check. If that yields good numbers, then it'll be time to start the engine, but I can't do that till I replace the gas. Unfortunately the pandemic has forced the shutdown of local disposal sites so I'm going to need to find an alternative safe disposal method.

My first choice is to try to give it away to one of the landscaping companies that service this area. I won't lie to them about the age of the gas.

If none want it, my second choice is to pour a little of it at a time into our other cars and gradually burn it off that way. I've been told that 1/2 gal is about as much as you want to try that with with a full tank of gas of new fuel. Is that so, or can I risk a full gallon?

There's probably 3-4 gallons of the old stuff in there now.

Btw, when I do a compression check, I assume that even with the plugs out it'll pump some old fuel into the lines and injectors. Should I therefore pull the fuel pump fuse or some other fuse or part first?
 
If the landscaping companies won't take the gas someone with an older diesel may take it. 80's and early 90's diesels will burn just about anything. Old gas works great to thin out used motor.

When you check compression the best thing to do would be to cut power to the fuel pump if you already got the old fuel out of the lines. I always pull the fuel pump relay but i'm sure there are ways that others will post
 
If the landscaping companies won't take the gas someone with an older diesel may take it. 80's and early 90's diesels will burn just about anything. Old gas works great to thin out used motor.

When you check compression the best thing to do would be to cut power to the fuel pump if you already got the old fuel out of the lines. I always pull the fuel pump relay but i'm sure there are ways that others will post
I pull the ecu fuse. Its right there under the hood. No tools required.
 
It might take a while before I can replace the old gas. But, since the very next step after checking compression is starting the car and letting it run a bit, it's going to have to wait till then anyway.

In the meantime, I've got other tasks, like derusting, cleaning and painting the front end, rebuilding the front calipers, replacing the clutch, fixing a trans issue. That ought to keep me busy for a while.
 
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