The old batteries in our M38 finally gave out in our latest cold weather. In the TM9-8012 O & OM manual for the M38, under "Battery Data", it gives very little information on the battery itself.
In an earlier technical forum posting, Ryan Miller discussed the Optima (D51R) battery as a replacement. I have read the specifications on their website.
My question is does anyone have the basic specs for the 2HH or 2HN military battery?
Or what cold cranking amps, amps, capacity, etc. are acceptable for use as a suitable replacement with the M38?
Also, it looks like both upper and lower batteries are the same. Is that correct?
Lastly, does anyone have recommendations?
Any help would be appreciated. Thanks.
Regards;
Thomas
Charlotte, NC
M38 Battery Replacement
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Thomas
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- Location: Van Wych, SC
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wesk
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When selecting a civilian battery you should first be sure it matches the 2HN spec as close as possible. Then you can decide using modern trade technology as you may desire.
The 2HN spec is:
12 volt
45 amp hour (20 hour rate)
Length 10 1/4"
Width 5 5/16"
Height 9"
Closest civilian battery group number is 22NF
A more detailed study of the 2HN's cranking ability:
Minimum time-(300amp @ 40 Deg F) Minutes 1.25 @ 150 amperes with a five second voltage of 7.2.
Minimum time- (300 amps @ 80 Deg F) to 1 volt/cell = 5.0 minutes @ 150 amperes.
Minimum life cycle capacity = 188 cycles
Minimum overcharge capacity = 9 cycles
Yes both cowl and under hood batteries are the same.
I personally do not use sealed type or gel type batteries.
The 2HN spec is:
12 volt
45 amp hour (20 hour rate)
Length 10 1/4"
Width 5 5/16"
Height 9"
Closest civilian battery group number is 22NF
A more detailed study of the 2HN's cranking ability:
Minimum time-(300amp @ 40 Deg F) Minutes 1.25 @ 150 amperes with a five second voltage of 7.2.
Minimum time- (300 amps @ 80 Deg F) to 1 volt/cell = 5.0 minutes @ 150 amperes.
Minimum life cycle capacity = 188 cycles
Minimum overcharge capacity = 9 cycles
Yes both cowl and under hood batteries are the same.
I personally do not use sealed type or gel type batteries.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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Thomas
- Member
- Posts: 36
- Joined: Tue Nov 21, 2006 6:00 pm
- Location: Van Wych, SC
-
Thomas
- Member
- Posts: 36
- Joined: Tue Nov 21, 2006 6:00 pm
- Location: Van Wych, SC
-
Thomas
- Member
- Posts: 36
- Joined: Tue Nov 21, 2006 6:00 pm
- Location: Van Wych, SC
Gentlemen;
After the last posting, I decided to purchase two (2) 2HN batteries from Star Electric Ordnance. Mr. Kevin Emdee was very helpful and shipped the batteries our immediately. Unfortunately, one came in damaged, but Mr. Emdee sent out the replacement immediately, and we worked through return claim with UPS in a matter of days. I am well satisfied with the batteries and in addition, he has other M Series electrical components available also.
I have since filled the batteries with battery acid from NAPA and then used the recommended two hour trickle charge before installing them in our M38. They fit great. The initial cold start took a few cranks, but once started the motor, gauges, and lights all work great. Actually, it feels like the Jeep runs better than before with the old incorrectly sized batteries.
Hal, Wes, thanks again for all your help.
Regards;
Thomas
Charlotte, NC
After the last posting, I decided to purchase two (2) 2HN batteries from Star Electric Ordnance. Mr. Kevin Emdee was very helpful and shipped the batteries our immediately. Unfortunately, one came in damaged, but Mr. Emdee sent out the replacement immediately, and we worked through return claim with UPS in a matter of days. I am well satisfied with the batteries and in addition, he has other M Series electrical components available also.
I have since filled the batteries with battery acid from NAPA and then used the recommended two hour trickle charge before installing them in our M38. They fit great. The initial cold start took a few cranks, but once started the motor, gauges, and lights all work great. Actually, it feels like the Jeep runs better than before with the old incorrectly sized batteries.
Hal, Wes, thanks again for all your help.
Regards;
Thomas
Charlotte, NC