Replacing Optima Yellow Top Start Batteries, need to verify exact model

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Replacing Optima Yellow Top Start Batteries, need to verify exact model

December 25, 2018, 09:56:28 pm

In preparation for our move South, I had some engine service work performed. I mentioned that the M11 has a tough time starting, (current batteries have 5/11 date codes) unless the boost switch is turned on. The shop where I had the work done indicated that the three start batteries needed replacement.

Per the excellent tips on the forum, I believe this is a job I can tackle. Disconnect negative terminal first, clean, prep cable, use dielectric grease at terminals.

I'd like to replace with OEM specs. The U320 has Yellow Top Optima's installed. It's a tight fit to verify the post type, and appears to be what looks like the group 31T (SKU: 8050-160) Optima battery.

Is this the correct battery model? I've attached the best photo I could snap of the posts.

Thanks in advance, Jeff

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #1 – December 25, 2018, 10:03:15 pm

Jeff, This is what mine are.
Optima Batteries 8050-160 D31T YellowTop Dual Purpose Battery.

These have the threaded top studs.

O'Reilly has these, cheaper, discount if you are an FMCA Diesel Power Club member
https://www.oreillyauto.com/detail/b/fleet---heavy-duty-5000/battery-accessories-16452/battery---automotive-16864/battery---best-fit-16245/ec27e4e51018/super-start-fleet-heavy-duty-group-size-31-top-post-battery/agm31t/4742641

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #2 – December 26, 2018, 01:10:22 am

The red tops are more designed to put out the needed amps. The deep cycle of the yellows optimas is rarely needed on the engine start side.

The optimas are designed to reject over charging heat by their spiral design and are made to handle the vibrations from the engine next to their location.

Every unicoach made had spiral wound optimas in it. Yes they are more money.

Lots of ten to 12 year life reports here.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #3 – December 26, 2018, 07:38:22 am

Roger, Thank you for confirming, I couldn't locate any views of the posts anywhere. I did order a can of the NO-OX-ID grease for the terminals that you recommended. Great tip on the FMCA club, we will join as O'Reily's has the best price so far up here in the Northeast.

Bob, I'm sold on the Optima brand, plus I simply don't have the time to modify the battery tray if I switch brands and they don't fit exactly.

From what I'm reading on the forum, I need to install a trickle charger on the start batteries too.

Thanks guys, we'll get these batteries $$$$ ordered today.

Jeff

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #4 – December 26, 2018, 09:06:09 am

Jeff, get a smart charger that senses battery voltage and temperature and charges accordingly, a 3 or 4 step charger. This will keep the start batteries in top condition for a long time. While you are in there clean all of the cable ends until they shine. Use a wire brush to get them clean. Then grease them up and connect. If you are using the original wiring to the batteries, rotate your batteries once a year. Move position 3 to position 1, 1 to 2, 2 to 3. Another long life trick and when you do, clean those terminals. Be sure you find out what the torque spec for the top post nuts is. Get a small inch-pound torque wrench and set them right.

Threaded stud terminal: 14-20 nm. (124-177 inch lbs)

Lots of chargers out there. I have one like this.
Amazon.com: BatteryMINDer Model 2012-AGM: 12Volt-2 Amp Battery Charger...

I now use one of these (only 40 amp to charge my 4 FullRiver L16 batteries and the start batteries, 5 year warranty)
Sterling ProCharge Ultra 10 Amp Boat Battery Charger

Are you coming to AZ this winter?

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #5 – December 26, 2018, 11:16:48 pm

Roger, thanks for the great advice as always I do fortunately have a torque wrench, calibrated to inch-pounds and will use it on the post nuts.

I never thought of rotating the batteries, great tip.

I agree, lots of AGM battery chargers out there and difficult to judge better/best. The one you recommended looks like a good value for features and will order tonight.

No AZ this winter, (2020 - yes)... We are headed south to the Florida Keys for Jan & Feb! Always wanted to visit the Keys and see the sunrise, and sunset over the water, and live by the sea... We'll be in AZ in late May and June. And, we have our 14 day reservation for Watchman CG. Can't wait to get this journey started.

Thanks again, hope to see you and Susan on the road again!

Best, Jeff & Kristen

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #6 – December 27, 2018, 07:52:12 am

Installation of a battery combiner can eliminate the need for a separate engine start battery charging system.

One less thing to be left off or fail as happened to me.

Auto connects both banks if either gets a charge and disconnects when either is discharging.

Blue seas automatic charging relay.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #7 – December 27, 2018, 08:52:24 am

Jeff & Kristen,
If you are heading to the Florida Keys for Jan and Feb, you best have made reservations. The campgrounds were getting harder to book sites and road side/parking lot camping is a Big NO-NO. Big fines when caught. We spent many years in the Keys during the winter months. Very nice, once you get use to the heavy traffic and not getting anywhere in a hurry. The last hurricane did us in. Reservations or any open RV parks became impossible to find because of the heavy damage to the Keys.

I replaced the yellow Optima batters with Red tops a few years ago. Still need the boast on to start the M11.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #8 – December 27, 2018, 12:24:51 pm

Something is wrong or has damaged your redtops, boost should not be needed. The redtops are nominally rated at 800 cca. The engine requires 2,200. Cabling? Starter motor? Something. If you ever let them be totally dead they need replacement.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #9 – December 27, 2018, 04:25:16 pm

Jeff and others,
Batteries loose capacity with age. A battery when new may produce 1000 CCA and after a few years it may only produce 500 CCA. I have tried both red top and yellow top for starting batteries. Both worked well. I prefer the yellow as the fully charged resting voltage is closer to the MK gel house batteries. Seems like less of a chance that one of the banks will get under or over charged, although to the best of my knowledge that never happened with the red. Last trip I was having to use boost on a cold start. Found out one start battery was dead and the other not too bad, but replaced both. There is a right and wrong way to connect multiple batteries in parallel. My start and house batteries were connected the wrong way when I bought the coach. I think it came from the factory that way. Both start and house were connected in parallel with neg and pos cable to the same battery. Gets more complicated with 3 batteries.

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #10 – December 27, 2018, 11:06:09 pm

Hi Bob, Jerry- Thanks for the tips and info. I am learning a lot about this Foretravel, sometimes the hardway... I think the start batteries, (which currently are Yellow Tops) got depleted while the bus was in storage last winter. We were fortunate to have it spend the cold winter in a heated warehouse, WITH 120v. power. Unfortunately at some point early in the storage season some electrical service was performed in the building and the separate outlet that I had the start battery charger plugged into became defunct. Noticed several months later when the M11 wouldn't crank. The drain, plus age likely shortened the lifespan... I will permanently add a hardwired charger as part of the install when the batteries come in next week. It did start well with the boost switch to assist, when we used it all this year. Oh, yeah... also learned, I should have been exercising the diesel aquahot every 30 days too, (we used the 120v. element). Working on that one, think its a clogged nozzle... We'll need that as we make our permant exit from the Northeast. Rudy gave me some detailed information to tackle that problem, (thanks Rudy!).

Dick, Sue- I guess it doesn't hurt use the boost switch, that's usually my practice too.
Sorry, I know the topic has strayed... Yeah, you are not kidding about scarcity of sites! We were able to get reservations over a year ago at Everglades/Flamingo, then move down to Geiger Key Fish Camp for late January and Sunshine Key CG for all of February when they reopened this spring. Really wanted to stay at the Jolly Roger, no luck. Yes, tough to "hide" a 40' Fortravel even for a night in the Keys, zero tolerance from our research... We're big bike riders, so we hope to peddle as much as we can and use our 10' inflatable w/10 horse merc to avoid some of the traffic if we can. Gettin itchy to get on our journey, finally !

All the best, and Happy New Year to all!

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #11 – December 28, 2018, 01:06:27 am

I lost my start batteries from a tickl charger failure. Hence the combiner from now on. Ml-ACR blue seas 500 amp unit.

Uses the boost wiring and location. Did not install the separate wire needed for the lighted feedback at the gauge.

I put accurate digital readout gauges into the two dash 12v outlets to double check the connect and manual disconnect functions. You can hear the click on and off fairly readily.

Too expensive and much safer to not find inadvertent dead engine batteries. We are sort of preppers. Dead engine batteries could be extremely bad

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Replacing Optima Yellow Top Start Batteries, need to verify exact model

December 25, 2018, 09:56:28 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #1 – December 25, 2018, 10:03:15 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #2 – December 26, 2018, 01:10:22 am

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #3 – December 26, 2018, 07:38:22 am

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #4 – December 26, 2018, 09:06:09 am

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #5 – December 26, 2018, 11:16:48 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #6 – December 27, 2018, 07:52:12 am

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #7 – December 27, 2018, 08:52:24 am

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #8 – December 27, 2018, 12:24:51 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #9 – December 27, 2018, 04:25:16 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #10 – December 27, 2018, 11:06:09 pm

Re: Replacing Optima Yellow Top Start Batteries, need to verify exact model

Reply #11 – December 28, 2018, 01:06:27 am

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