1989 12-HT how do I replace my fuel filter? (1 Viewer)

[Colington]

This post may illicit a chuckle from some because it's likely very easy but I've simply never done it (and perhaps it belongs in the diesel/24v section, but I get more replies here.

I took my cruiser out today and noticed a strong diesel smell so I went home and upon further inspection I noticed that my fuel filter is dented and squirting from a pinhole ALL OVER THE PLACE! I have no idea how this could have happened but it is what it is.

I've seen a diesel filter replaced once when I was 7-8 years old and I recall a pump primer on top and my dad seeming to fuss about plugging the line so it didn't drain back to the tank... Is it true the engine pulls fuel in and through and there's no pump??

My 1989 HJ61 12-HT has a totally different set up. Basically there is an "in and out" line and the whole assembly mounts to the top of the engine. I ordered an OEM filter replacement from SOR but when it arrives I have no idea what the process is other than wiping diesel on the seals for a proper seal... Any help would be great. I guess I'll need a filter wrench too unless there are other diy options??

 

[gregnash]

Looks like it would unscrew like a conventional oil filter. Get the FSMs if you havent already and start reading..

 

[Colington]

Is this correct?

 

[DickM]

No chuckling here- if you don't ask, you won't know,
And I would love to have your problem, because it would mean I had a Toyota diesel.
Good luck with your problem, there are plenty of guys who (unlike me) know the 12 HT.

 

[cwwfj60]

sometimes they can be a pain if they are tight, remove the filter, fill new filter with diesel, if you have a nice full filter sometimes you don't even have to bleed it, at least in my experience. If it doesn't start or starts and dies, or if you want to play it safe, crack one of the injector lines and crank the engine over, it will spurt out some diesel and then you can close the line and it should fire up and run.

So to be clear, change filter, fill up new filter with diesel as possible, crack injector line at injector, crank engine till diesel spurts out (or no bubbles), tighten injectors line and then you should be good to go.

The FSM you pulled up would allow you to prime the filter after replace it which is a good idea if you don't keep it full. Then proceed with what I said if needed. I forgot these had the priming pump on them, very handy.

 

[Tapage]

I'm not positive on 12H-T engine but the 2H it's very, I mean very picky with the air in the lines .. that's why I have an electric pimp to help me bleed fill the filter and then bleed the system ..

 

[Dieseler]

If you fill the new filter as stated you should not have to pump the primer...usually the plunger ends up leaking from old dried O rings after use. I have never had to use the priming pump since there is already fuel in the line leading to the filter if you open the bleeder valve and crank the motor most of the air will escape the filter.
Bleeder valve is the nipple with the black rubber cap in your picture.
Usually any air in the injector lines will pass through once the engine starts it will run a little rough until the air passes.
I use a strap style oil filter remover that is attached to a metal tube which fits a ratchet and winds the strap around the tube as you crank it...... one of the best filter removers I have owned never fails.

 

[hj 60]

Check if your prime pump is working fine and problably replace it before it starts leaking.

If the filter is rusted trough replace a lot more because it is worth the investment, the engine looks very clean.

I use contaminated diesel from an old filter to clean stuff, the prime pump should be able to fill it fast.
Some use injector cleaner in the new filter (or seafoam, that stuff)
Also it is a bit self healing so if it starts just rev/drive and prime again if it does not pick up normal operation.

The filter is easy to remove:

And I always have a rag, plastic tube and wrench #10 attached to the bleeder because I don't want to search for it if I have to bleed in the middle of the night.

If the dieselprimer pump is leaking: BOSCH Hand Primer Pump Diesel Fuel Feed Pump # 2447222126
Also check (if you have) the small inline mesh filter that is just before the primepump.
22529 22529-67010 FILTER, FUEL PUMP. FILTER, FUEL PUMP (08.1980-08.1987) 3B,2H..BJ60,HJ60;

old filter:

 

[JSparks]

having this very problem with a fuel leak through that primer pump at the moment and just ordered the bosch replacememt, i liked the look of this one Heavy Duty Monark Ultimate Hand Primer Pump | Product | MercedesSource.com but shipping was more expensive and would take longer to get to me.

ive always found on the 13bt that just filling the new filter and wacking it on is enough, dont need to prime with the pump at all which is good considering it just spews fuel out over everything currently.

 

[VX 12HT]

yep just done mine on the weekend no need to bleed like in the manual. Were gloves i filled up the filter with fuel but still used the priming pump and yes smear fuel around the o ring seal on the new one and just tighten firmly be hand. Set up some rags underneath the filter housing to catch any diesel if you spill any but yeah main thing is to fill up new filter with diesel to prevent bleeding the system the factory (longer) way. May run a little rough for a few seconds then should be good.

 

[KeepCruzin]

My 12HT always has a hard time priming, even with a new Bosch priming pump. So if you need a little extra priming pressure, I shove a rag in the fuel filler neck, and run a bit of high pressure air in there until i see fuel squirting out of the bleed nipple, then have a friend tighten down the bleeder valve.
^Thats only if you have a hard time priming the system after the new filter though.

I agree 100% with all the answers above. All great advice.

Good luck!

 

[Colington]

I just wanted to thank everyone for their input. I was able to replace the filter without a hitch. I wisely decided to but a filter wrench AND a strap style filter removal tool and I'm happy I slashed the extra $4.99 for the strap style as it was a cinch to use and clearance didn't affect it. The old claw style is a bollocks design IMO.

I ended up laying an old tee shirt under the old filter so as not to spill diesel. It came off easily enough and I poured the old diesel into the new filter. It filled it 5/8'ths or so and I didn't bother bleeding or pumping. I just cranked her over and had 5-10 seconds of rough idle then she died. I turned her over again and she sprang to life. I pulled the choke a bit and let her purr for a few min before taking it around the block to test. Flawless.

This site and this truck has really allowed me to gain confidence in working on my own rig. Thanks for the help.

Ps. SOR got my filter to me in 48 hours and I was very impressed!!

 

[VX 12HT]

excellent even though i have owned my 12ht for a few years i first researched on here to change fuel filters sure beats having to bleed the system how the instruction manual wants you to.

 

[darthvincor]

I replaced the fuel filter once on my 2H, and it was really easy. I also replaced the primary filter as I was at it (mesh screen in front of primer).
I installed it dry and simply filled it up using the primer, and it ran again after that.

I even ran out of fuel once, and it sufficed to just bleed the fuel filter. I've luckily never had to bleed injectors, maybe you'll be lucky too.

 

[relaxedcruiser]

Hi all,
while surfing around I came across this thread as I was after this Bosch pre pump, my original pump probably spills more diesel than it actually pumps.
I am replying to this tread as I am a bit horrified to read that it seems to be common practice to use the diesel which is in the old filter to prefill the new one...Please don´t do this!
The possibility to introduce all kinds of unwanted stuff (which has been succesfully stopped by the old filter to protect the injection pump) into the new filter is quite high. It wouldn´t matter very much if the new filter would be filled using only into the outer holes which is the "dirty" side of the filter. Quite likely is that one would pour the diesel into every hole including the one in the center which is the exit of cleaned diesel.
Screw it on dry with a bit of lubricant on the rubber seal and pump it with the pre pump, its fast easy and safe. If the pre pump like in many cases is buggered you can use a large syringe, attach it with an short piece of tube to the bleeding nipple and just suck the diesel slowly up from the tank. When the syringe is at the end of the stroke close the bleed nipple and repeat the procedure until the bubblefree diesel emerges from the bleed nipple. It pays to "seal" the bleed nipple tread with grease beforehand as otherwise air could be sucked trough the tread into the syringe...misleading that the bubbles would come out of the filter.
I think your IP is thankful for the clean diesel.

 

[Jarradical]

Just changed the fuel filter on my 12HT hj61.. didnt have to bleed at all, used SST to remove filter, poured diesel from old filter into new, used SST to refit, turned over, started fine ran rough for 3 seconds then I thought I heard a faint voice say 'thankyou' and that's was all she wrote.. bring on a million kms

 

[relaxedcruiser]

Hi - haven´t you read what I wrote in the last post before you...please do not pour the dirty diesel of the old filter into the new filter - it´s very likely to introduce dirt whether it be from the outside or inside of the old filter into the new one.

 

[Jarradical]

Hey mate, yea I did see your post, I didnt have any clean diesel on hand and my fuel filter is only 5,000kms old, thankyou for the insight though, will be doing it next time

 

[relaxedcruiser]

You could also use the hand pump to prime the filter and bleed it via the nipple on the outlet. Very easy and clean if you attach a clear tube to it.

 

[duncanrm]

Old thread I know.. but the OP has the Bleed Nipple installed on the inlet to the filter. It should be on the outlet.

Also.. I prefill my new filters with Liqui Moly Diesel Purge Plus.. 100% concentration, zero bleeding/priming then required and the pump and injectors get a nice clean.