Vacuum problems?

[BennyD]

Currently in Portugal (on European tour) with the beloved Bongo!

The brake light has started coming on intermittently (normally whilst going. downhill), but the fluid level is fine and the brakes seem to be working ok. We have also started stalling quite regularly - normally when slowing down for a roundabout. Normally starts fine, but after a stall starting takes a lot longer.

Could this be a vacuum problem, and if so what should I check first?

[Driver+Passengers]

I'm not sure - but two thoughts spring to mind.

Check the voltage on the alternator? I think the ABS light will come on if it's dodgy?
Have you replaced fuel filter recently?

[Northern Bongolow]

is it using more fuel than usual.??.
if yes it could be the 2 solenoids near the glow plugs (cold start solenoids). when the vac pipes get hot they can suck flat,this holds the cold start solenoid on, which makes it run like the choke is on and run poorly. one of these solenoids also comes on when the aircon is used, does your aircon work and was it on. what is the tick over speed??.

put your hand under the fuel pump when the engine is cold, is it wet with diesel ?. if yes then the advance piston side seals may be shot, or the shaft nose seal is sucking in air, but your symptoms sound like side seals as when you take your foot off the gas the pump leaks fuel as it dumps pressure. driving and accelerating once running is usually fine or just a small drip.

[BennyD]

Thanks for your response!

Can't get under the seats at the moment but will check those things tomorrow.

Fuel economy is pretty much the same as usual. Air con works fine and the stalls happen whether its on or off. Tickover is normally around 800 - when its going to stall you can see the revs dropping below that as the engine idles, so can normally save it by pumping a bit more gas, but once it goes to stall it never recovers its idle revs until the engine is restarted, at which point it's fine.

[Northern Bongolow]

check out this sensor its at the front of the engine under the front edge of the fuel pump on the drivers side.
remove the connector then undo the bolt and clean the sensor, i saw one recently that was drowning in leaking fuel, it all drained out when removed.

http://igmaynard.co.uk/bongo/forum/view ... =ne+sensor

[BennyD]

Took a while to take a look but this is what I found:
• The vacuum In & Outs of the 1st solonoid (18-741C - the one nearest the front) have snapped off, and the small white plastic double 'T' piece (13-945J) had become totally disconnected. Have reconnected the T piece but the broken solonoid needs replacing. Any ideas where to find one? Also do you know which ones do what?
http://lushprojects.com/bongopartsmk2/c ... 1of02.html
•The area on the nearside front on the engine is pretty oily - could this be the evidence of bad side seals? & is it a massive job to replace them?
•Haven't managed to remove the pulse generator/rev counter yet (mostly as I couldn't get the connector undone), but will try to soon. It's occasionally intermittent so worth doing anyway!

Thanks,

Ben

[BennyD]

Update:
Have removed sensor and it was indeed think with oil! Have cleaned and put back so will see how we go!

[Northern Bongolow]

Took a while to take a look but this is what I found:
• The vacuum In & Outs of the 1st solonoid (18-741C - the one nearest the front) have snapped off, and the small white plastic double 'T' piece (13-945J) had become totally disconnected. Have reconnected the T piece but the broken solonoid needs replacing. Any ideas where to find one? Also do you know which ones do what?
http://lushprojects.com/bongopartsmk2/c ... 1of02.html
•The area on the nearside front on the engine is pretty oily - could this be the evidence of bad side seals? & is it a massive job to replace them?
•Haven't managed to remove the pulse generator/rev counter yet (mostly as I couldn't get the connector undone), but will try to soon. It's occasionally intermittent so worth doing anyway!

Thanks,

Ben

if the nearside is leaking oil you have a problem, possibly just the rocker gasket (easy cheap fix, available from the bongo fury shop). the fuel pump seals are on the drivers side, not a hard job to do, but you may need the hands of a Japanese ivory carver, to get in to do the job.

the 2 solenoids do cold start. the left one does full cold start (when coolant is under approx 10deg c), then above that it turns off then the right one takes over,this does half (choke) until about 50 deg c coolant temp, then it is warmed up so knocks off. the white plugged one is also there to pick up the revs when the aircon is switched on, to help with the extra load on the engine.

[BennyD]

Sorry, being thick! It's the drivers side that's oily

[Northern Bongolow]

the drivers side oil leak, high up, near the front, is usually the camshaft front oil seal, most bongo.s have it, most dont worry about it and leave it, it doesnt loose much according to the stick measurement, but it can look messy.

[BennyD]

Great thanks!

Any idea where I can get a new solonoid valve?

B

[Northern Bongolow]

most mazda cars have them fitted---------scrap yard trip time.
the petrol and diesels have them fitted, the ones with egr fitted. they can look slightly different on some models but you can pull off the little black block (the air filter) this can be put on to another port on the valve to get it configured the same as the one you need.

failing that, just repair the old one by pushing in a small tube, i use small roll pins, these are heat proof and give a good stub to fit the pipe.
fit a small roll pin into the stub/hole, then slide over a larger roll pin, this gives the correct pipe sized stub.cover in epoxy.

http://www.google.co.uk/imgres?newwindo ... 127&ty=134

check its working ok first by putting 12v to it from the battery, if not squirt in wd40 then tap it to free it off. they get rusted internally.

[BennyD]

Great thanks - will have a hunt!

Do you know if the valves are normally open or normal closed?

[Northern Bongolow]

when not connected it is closed.
the vac is held in the common supply line at the rear until the ecu switches it open, then this opens the valve to allow vac through the vertical port at the top which acts on the throttle diaphragm itself via the pipe work.