Page 11 of 12
Re: Water in cylinder 2
Posted: Wed Mar 15, 2017 10:19 am
by Bongolia
bongovi wrote:Bongolia wrote:White smoke filling the street is a bit concerning.
Question , once the engine is up to working temperature and you switch off, when restarting after a 15 mins or so does the white smoke and lumpiness reappear or is it just from initial cold start?
To eliminate the turbo letting by, when the engine is at working temp and smoke cleared, switch off,clamp off the turbo water supply feed and return, allow it to cool down for 10 mins or so,start the engine and idle it for a minute or so, no more then switch off and perform a cold start after block temp has gone cold, best over night. Run it for a couple of minutes have you still the white smoke?
Cheers - will re-test today, but I'm *pretty certain* that the lumpiness/smoking is completely gone once it's been cleared, and it seems to clear quicker if I rev (i.e. it won't fill the street if I rev it).
I think I follow with the turbo tests. I haven't clamped off a tube before, so not sure what to use - I can only think of those Ikea sandwich bag clamps for now! This test will show if the turbo's not sucking in coolant? As there's no white smoke once cleared initially, I'm hoping that's already a low-likelihood issue.
Yes, thats the idea.
I dont think the sandwich clamops would give the pressure you would need but could be wrong!
https://www.amazon.co.uk/Dapetz-Piece-B ... ipe+clamps
These should do the trick,not sure of build quality but the look very similar to the MAC ones I use, may be a useful addition to the tool kit.
If you use mole grips be very careful not to over tighten them, very easy to do, as you can damage the cords.
Re: Water in cylinder 2
Posted: Wed Mar 15, 2017 4:06 pm
by Northern Bongolow
if you click on the number you quoted above, it expand the info available in the left margin this should include the mazda part number.
most same period cars use this part in various guises, just any parts place should have similar.
https://www.google.co.uk/search?q=mazda ... 40&bih=770
Re: Water in cylinder 2
Posted: Wed Mar 15, 2017 4:28 pm
by bongovi
Northern Bongolow wrote:if you click on the number you quoted above, it expand the info available in the left margin this should include the mazda part number.
most same period cars use this part in various guises, just any parts place should have similar.
https://www.google.co.uk/search?q=mazda ... 40&bih=770
Cheers for tip. I was quoted £38+VAT for the NRV part in the end. Said I'd check breakers etc. first. Have a feeling it's going to have to be new if not too brittle to re-use. I take it I can't use a generic NRV from ebay for £3.99?
In investigating I managed to snap part 93-5104[*], below the NRV going into the air tube. Have glued it back on for now, badly, but am going to have to extract the remainder and find/fit a new one of those now too! I'm not heavy handed, honest, these old plaggy bits are just coming apart in my hands!
When I snapped it I was in the process of tightening the EGR manifold (if that's the right term) because it was leaking fumes on startup. The white smoke cleared when I revved, so it's got to be something to do with the startup process. Coolant levels are stable since yesterdays test runs. It idles at 900-950ish and is just lumpy without slight revving. I don't know if swapping out the NRV and its connecting bits will stop the issue, or if it's the solenoids NB was talking about.
[*] -
http://lushprojects.com/bongopartsmk2/c ... mgno=.html
EDIT - forgot to say I had a fish around for the banjo filter after reading posts on that causing smokiness and then the factsheet, but given that for the life of me I couldn't release the 5mm allen key (no space + bending key) I abandoned that for now.
EDIT 2 - just realised 93-5104 is the vac tube - do I now need a whole new air inlet tube, the large one round the back of the head?
EDIT 3 - found
http://mazdabongo.com/catalog/mazda-bon ... ll-models/ this is at least £28 all-in. Would a generic £3.99 jobbie work as well, as mentioned above?
Re: Water in cylinder 2
Posted: Thu Mar 16, 2017 4:27 am
by Northern Bongolow
the 3.99 job will be fine, its only a sprung loaded ball bearing thing, or even cheaper a flap of plastic blocking a port. its got to be thermal plastic though as it gets a bit warm round about.
this post may help with the stub repair.
http://igmaynard.co.uk/bongo/forum/view ... =3&t=50170
Re: Water in cylinder 2
Posted: Thu Mar 16, 2017 6:40 pm
by bongovi
Northern Bongolow wrote:the 3.99 job will be fine, its only a sprung loaded ball bearing thing, or even cheaper a flap of plastic blocking a port. its got to be thermal plastic though as it gets a bit warm round about.
this post may help with the stub repair.
http://igmaynard.co.uk/bongo/forum/view ... =3&t=50170
That post was incredibly useful. I'll drill out and wodge in the new stub, with a bit of Bostik or silicon sealant for good measure.
Went for an alu one (6mm) and a brass straight-through connector (4mm) so will have to encourage the vac tube over it, but shouldn't be an issue? Hoping that NRV will not mess with the vac settings on the Bongo. Suspecting that's what's causing the startup smoke, so will be interesting.
--
NRV:
http://www.ebay.co.uk/itm/321650203424
Straight-through:
http://www.ebay.co.uk/itm/131711097258
Re: Water in cylinder 2
Posted: Mon Mar 20, 2017 5:04 pm
by bongovi
Did the stub repair, was very quick. Needed to warm the rubber a little to get it over the ends, but the vac is back. Also blanked off the EGR while I was at it, given that little bit of extra room I had without the stub in place.
However, that didn't immediately clear the white-smoke on start, only revving slightly still cleared that, as before. Took it for the 'Italian tune up' folks mention here and it ran as good as ever, hopefully clearing out any remnants.
So will watch for smoke on the next run from cold. Coolant levels are steady still. Suspecting those solenoids or something turbo-side if not.
Re: Water in cylinder 2
Posted: Mon Mar 20, 2017 5:49 pm
by Bob
Useful update, thanks.

Re: Water in cylinder 2
Posted: Tue Mar 21, 2017 10:45 am
by teenmal
Just Remember.
" Coolant alarm only went on when sat on drive after getting home "
This is one of the reasons that this type of alarm has been found to be unreliable.
If in Any doubt stop the engine ASAP let it cool down and check the level.
Re: Water in cylinder 2
Posted: Tue Mar 21, 2017 2:06 pm
by bongovi
Northern Bongolow wrote:the cold start solenoids, (the 2 black switches with the vac pipes on near the glow plugs) are tick over switched on-off, that is to say they only work if the tickover is set to about max 750 if i remember right, above this the puter thinks its warming up so turns em off, or you drive off while warming up. the increased revs also opens the green one way valve via neg pressure in the turbo pipe, this dumps the vac used to operate the cold start solenoids but then opens the egr valve if still plumbed in,
the first cold start solenoid works up to about coolant temp plus 10 deg c then turns off and turns on the second solenoid up to about plus 40-50 if i remmber right. then they both turn off and the egr turns to open.
poss set your throttle cable or tickover and make sure the cold start solenoids are working at the right time.
search for cold and start and solenoids, the AND is important in the search proccess, it finds each word then not just the sentence. theres some older good threads out there.

Cheers, teenmal, noted - think you mentioned on page 1 of this thread back in December! Well worth bearing in mind for us and anyone reading this in future.
Still smoking a fair bit on start, so looking to Northern's comments above now. If start tickover is running at about 900-950, does that mean it's set too high for the first solenoid (or have I read that wrong)? It's well lumpy if I don't give it a bit of throttle, and puts out lots of white smoke.
I've just replaced the one-way valve with a slightly larger one (6mm vs 3mm) and blanked off the EGR (in one place only, at back/behind head) so have messed with the start system a bit.
Will look around for the search terms you mentioned again, hope to find some more clues.
Re: Water in cylinder 2
Posted: Tue Mar 21, 2017 2:35 pm
by Northern Bongolow
it all depends on the coolant temp and if the motor is already warmed up.
first make sure the aircon is off properly, i will come back to this later.
if the coolant temp is less than about 10 deg c and the bongo is started without throttle, the rear most solenoid of the 2 (the left one) comes on, you can test this by removing the lecky plug the revs should then drop and run lumpy, refit block the revs should rise, but NOT ABOVE ABOUT 850-900 OR IT WILL TURN ITSELF OFF VIA THE ECU.
when the coolant level gets to just above 10degc the left one turns off and the right one(with the white plug) turns on, operating it at (half choke). this holds the revs up a little but again not above the 850-900 threshold. at about 50 degc both are switched off as the engine is at min operating temps. the right hand (white one) also picks up the throttle a bit when the aircon is switched on to compensate for the load.
all the above presumes that the throttle cable is set correctly and that the end of the cable is contacting the plunger at the end of the throttle cable, also that the 2 pipes that supply the solenoids from the vac pump and fuel pump activator /diaphragm/plunger are on the right way round and connected.
the white plugged solenoid is famous for seizing up or sticking as its used more than the other to test this simply unplug one or both and swap the lecky over to the other one, it wont work right but may give you a clue to what is or not working, they should click cleanly on and off when the controlling temps allow.
hope this helps a little.
Re: Water in cylinder 2
Posted: Tue Mar 21, 2017 4:59 pm
by mikeonb4c
teenmal wrote:Just Remember.
" Coolant alarm only went on when sat on drive after getting home "
This is one of the reasons that this type of alarm has been found to be unreliable.
If in Any doubt stop the engine ASAP let it cool down and check the level.
Strange. Me and many others have found theirs very reliable. What is the cause of this reported unreliability just so we can be aware.

Re: Water in cylinder 2
Posted: Tue Mar 21, 2017 5:41 pm
by Bob
I'd also be intrested to know which type of alarm and what the specific problem is, please?
There are some very cheap e bay ones and some well known quality ones.
Re: Water in cylinder 2
Posted: Wed Mar 22, 2017 6:34 pm
by bongovi
Bob wrote:I'd also be intrested to know which type of alarm and what the specific problem is, please?
There are some very cheap e bay ones and some well known quality ones.
I think teenmal was speaking more generally as I didn't say what kind of alarm it was, nor that there was a problem with it. It's a Haydn. If I recall correctly the issue with the screw-in-tank type can be coating of the screw and so a lack of reactivity. But that doesn't seem to be the case for me as it goes on and off immediately as the level moves, as it did on the day of the 'incident'. I actually have it running off the leisure batt at present, so can go on at any time. Doesn't affect functionality, apart from not doing the test beep on every startup. I also gummed up the speaker with glue to quiet it down a bit. Still very audible.
Separate issue today (haven't had chance to look at solenoids/vac tubes properly yet, but great tips from Northern) is that the engine temp dial worked intermittently on the way home. This, coupled with the white smoke on startup, unless revved off, are making me very sus about the ECU/vac tubes/solenoid workings.
Re: Water in cylinder 2
Posted: Wed Mar 22, 2017 6:48 pm
by Bongolia
bongovi wrote:Bob wrote:I'd also be intrested to know which type of alarm and what the specific problem is, please?
There are some very cheap e bay ones and some well known quality ones.
I think teenmal was speaking more generally as I didn't say what kind of alarm it was, nor that there was a problem with it. It's a Haydn. If I recall correctly the issue with the screw-in-tank type can be coating of the screw and so a lack of reactivity. But that doesn't seem to be the case for me as it goes on and off immediately as the level moves, as it did on the day of the 'incident'. I actually have it running off the leisure batt at present, so can go on at any time. Doesn't affect functionality, apart from not doing the test beep on every startup. I also gummed up the speaker with glue to quiet it down a bit. Still very audible.
Separate issue today (haven't had chance to look at solenoids/vac tubes properly yet, but great tips from Northern) is that the engine temp dial worked intermittently on the way home. This, coupled with the white smoke on startup, unless revved off, are making me very sus about the ECU/vac tubes/solenoid workings.
That sounds more like an electrical connection issue from here. I understand there is an issue with the gauge if I remember correctly from old posts on here. Might be worth giving the terminal and connector a bit of a clean up first.
Re: Water in cylinder 2
Posted: Thu Mar 23, 2017 4:19 am
by Northern Bongolow
the temp gauge on the dash does not go through the ecu so it wont be that, the wire that goes to the sender top is usually tight as it crosses the rocker cover front from the loom on the passy side to the sender at the front of the head on the drivers side. sometimes the top of the sender comes loose, its just a crappy rivet, try a clean of the connection and check the top isnt wobbling about.
all the temp controlling readings are taken at the fan switch sender above the starter motor driverside on the cylinder head, these are fed to the ecu and control the starter solenoids, egr and the front coolant fans etc. this is known to fracture at the the plastic/brass joint where the plug connects,