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where is the fuel pump and the fuel filter?

Started by mvladutoiu, April 05, 2014, 01:24:37 PM

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mvladutoiu

Hi guys,
a week ago I took my '86 FJ1200 out for a spin around the area, as it has been sputtering just a tad, and I thought it was some bad fuel (they still add water sometimes at the gas pump in Eastern Europe). I had the unpleasant surprise to have the bike die on me on the road, but it died as if it had no gas (although plenty in the tank). Would not start pushed, or any other way. The fuses are all fine. I ended up pushing the bike 11 km home (I am still sore a week later). I finally had the time to pull the tank off. I looked all over the forum, and couldn't find an exact topic for this, so here goes my question: where is the fuel pump and the fuel filter located on the '86? I suspect on the left side, as I followed the small line from the tank to it. However, how can I know for sure it if is a problem with the fuel pump or not? Also, does it have a fuel filter? If so, where? How about the part on the bottom of the tank where the two main hoses clamp? if I take the hoses off, is it supposed to NOT leak even if there is plenty of gas inside and the tank is level? I even tried blowing with my mouth into it, nothing will budge. Any help or additional questions or pointings to other forum topics are welcome. I have 80k km on it.
Thanks.

big r

The 86 is a gravity feed. Doe's not have a fuel pump. Did you check your fuel level? Not trying to be a smart  ass here, when you opened the fuel cap did you here a small rush of air? Could be that your fuel cap breather is not letting air past. See the files section for the flapectomy file. I had the same problem with my 86. Big R

big r

Quote from: big r on April 05, 2014, 01:41:24 PM
The 86 is a gravity feed. Doe's not have a fuel pump. Did you check your fuel level? Not trying to be a smart  ass here, when you opened the fuel cap did you here a small rush of air? Could be that your fuel cap breather is not letting air past. See the files section for the flapectomy file. I had the same problem with my 86. Big R
Also the fuel filter is inside the tank, attached to the petcock

keand3

Also, look how your fuelline is routed... If they are routed incorrectly the lines themselves might cause a fuel starvation http://www.fjowners.com/index.php?topic=9266.msg87760#msg87760

Whant to check out my photos on the bike??
https://onedrive.live.com/redir?resid=828DDEC8DF631CA5%21103

mvladutoiu

Thanks guys... I'll try taking the petcock and gascap apart, cleaning and putting everything together right, and will let you know if that solved the issue.

Pat Conlon

Yep.....Correct fuel line routing is most important. The first thing to check.

If the fuel line is routed correctly then perhaps your vacuum petcock is acting up?

The fuel petcock (on the bottom of the tank) opens and closes based on a vacuum line going to the #2 intake manifold. When the engine is starting or running, vacuum is present and the petcock should be open flowing fuel to the carbs. When the vacuum signal is stopped (engine off) the petcock closes, shutting off the fuel.

I think your petcock could be closing, shutting off the fuel.

Here's how to check:
Check the rubber vacuum line going between the engine and petcock. Check the line itself for cracks and both ends to make sure you have a good seal.
After that, do a suck test on the petcock. Hook one end of the vacuum line up to the vacuum port on the petcock and on the other end, lightly suck on it. You should hear a click, and the petcock should open, flowing fuel. When you lightly suck you should not be able to draw air thru the petcock. This indicates a leaking diaphragm in the petcock. Not good.
When you suck, put your tongue over the opening in the vacuum line. It should hold a vacuum. When doing this, if the petcock closes then the diaphragm leaks. Not good.

If this is happening then I suggest buying a new petcock. No rebuild kits are available. A new '86 petcock is expensive. A less expensive alternative is the '84/85 petcock but you do lose that (stupid) reserve switch function you now have. The '84/85 petcocks do not have the reserve switch.

Check out RPM, he has the new oem petcocks and ships overseas.... Hope this helps.  Pat
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

mvladutoiu

Hi Pat,
thanks for the detailed advice. I am just now coming from the garage, where I did just about everything... I took the gascap apart, cleaned it, looked fine... took the petcock apart, inspected the diafragm, it looked clean, although not perfect... I did a suck test, but I am not definitely sure whether it is leaking anywhere or not. Will try it again during daylight, to watch it and inspect it more carefully. Anyways, after putting the lines back together and cranking it a hundred times, I managed to start it and warm it up, but it still sputtered all over the place. After it warmed it, and seemed to sputter less, but if I gun it, then it would start sputtering again, and want to die off. Assuming the petcock and the gas assembly is fine, is there a next possible culprit, or should I just keep investigating the gas feed?
Thanks a lot. And you're right, a new one is awfully expensive.

FJmonkey

The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

Pat Conlon

Well now,  if it starts, that's a start (get it? :rofl2:)....then gas has to be flowing to the carbs...still verify the petcock via the suck test. See if you can draw any air thru the petcock diaphragm...yes, they are expensive, that's why the '84/85's are a better deal. A additional benefit on the '84/85 petcock is the 'Prime' setting (P) not available on the '86+ petcocks. If you have any problem on the road with the 84/85 vacuum petcock you can turn the petcock lever to Prime which manually opens the petcock....so you don't have to push the bike... Don't ask...

However, if the bike is running, sputtering indicates that it is time to clean your carbs, check the float heights and synchronize them.
All this info is covered in the Carb Files, so please read up....When cleaning, pay attention to the choke circuit (esp. the fuel pick up passage in the bowl) the idle circuit, the pilot jets and those little fucking holes in the needle jets (aka: emulsion tubes) :ireful:

Don't leave us hanging...let us know what you find...what you did to fix it.  Cheers Pat
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

mvladutoiu

Well, I am still working on the petcock and hoping that it is the only problem. It would be awfully coincidental after two years of flawless operation, all of a sudden both fuel petcock and carbs to go out of whack (although not at all impossible). Meanwhile, I have taken the petcock off of the fuel tank (again), took it apart to every little piece, and took some pictures of what I found, and the last two pictures were taken after doing my own reconditioning (meaning miniatural work with special glue). I'm gonna let it dry and try on Monday to put it back on the tank and crank her up.
I'm just wondering outloud: is there a way to fit a fuel pump on the '86?
Also, I looked into your suggestions as to using a petcock of a '84-85, but I am not sure how I would reach under the tank to turn the gas on and off every time I get going. The petcock is awfully well hidden. I used to have a '78 Honda which had the switch very handy, but I cannot figure this one. Or am I not understanding something?
Any feedback about the pictures may be useful. :-)








Pat Conlon

No need to worry about reaching under the tank with the '84/85 petcocks. Under normal conditions they open and close based on a vacuum signal, just like the '86~88 petcocks.

Only in a emergency would you use the prime setting. Doing that will manually open the petcock and get you home. Once home, you will want to lift the tank and shut off the petcock so you won't flood the carbs, and crankcase, and garage floor, etc...

Yes, I am considering converting my '84 over to a fuel pump.
When you do this, you have to open up the carbs and install different float needle seats (smaller)
I can use my oem '84/85 petcock by simply turning it on to the prime setting.
You can't. You don't have a prime setting on your petcock. You would need to install a manual petcock.

Electrically, I haven't figured it out yet..... The simple idea is power the pump via the ignition key but that has dangerous consequences. In the event of a crash, ignition key left on, the fuel pump will keep running feeding fuel to a bad situation.
I'm leaning towards a normally open relay, powered off a signal to the TCI.....When the engine stops, pump stops. I just don't exactly know how yet.... This mod is on my list.

Good luck on the repairs to your petcock. I do hope it works out for you. After you get it together let us know how well it holds a vacuum. Several folks inc. me, have tried.
In all cases (so far) we have had to bite the bullet and buy a new petcock.
The environment the petcock lives in is subject to a lot of heat off the top of our air cooled engines. It's not surprising that after 28-30 years of exposure, that we need to replace them.

On the petcock safety wire, I suggest looping the wire around the angle fitting to assure the wire does not slip off the angle fitting. A smaller gauge wire will help. Baling wire or ss safety wire is good stuff..

Cheers
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

mvladutoiu

Well, I put everything back together, and gave the bike a spin around the block, got the engine warmed up, and it seemed to run fine. No sputtering whatsoever, just somehow it felt a little underpowered on the throttle. I didn't go too far (I was afraid of having to walk it back home again), so I don't know if and how long my repair to the petcock will hold, but it seems to do it for now, so it will have to do until I order another petcock and it arrives in the mail. I found on ebay a few used petcocks, much cheaper than the new ones, but then, I buy an old one, it might do the same in a few months, no guarantees.
Even if the petcock gives up the ghost again tomorrow, at least I am glad that I figured out that the only real problem is the petcock, the rest seems just fine. I will try finding an 84-85 petcock, but a new one seems even harder to find on the European market (Germany, or somewhere closer, since mailing costs from the US are quite high, plus I run the risk of having to pay import duties on it when it arrives at the post office, from Germany it would be EU delivery, so I'd be covered). If ya'll stumble across a new petcock decently priced and shipped from a European country, please let me know. Really appreciate all the help.

Pat Conlon

RPM has new petcocks at below dealer prices, and they ship to the EU....

Look no further...
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3