Water in cylinder 2

[Bongolia]

[Um-Bongo]

Now please try not to boil this one...

[mikeonb4c]

Great result. The experience would have scared me stupid

[bongovi]

Cheers again. Here's some pics from the project: https://imgur.com/gallery/ubtdd

The main problem I've had since the test runs is the press-fit coolant elbow slipping out of the new head under the pressure. So I've tapped it back in and used silicone sealant all around it to hopefully hold it in place. The shop I got the head from said to tap into the elbow around it with a point/hammer, but I haven't done that properly yet.

Any other tips on keeping elbows in place? See the album for a visual. Imagine it pushed back in with a bead of sealant around it now...

[Bongolia]

Nice crack.
That item should be a new component. Its an interference fit in the head about 12.00 quid I think, Bongoshop may have them, certainly not worth risking that after everything you have done.
Silicon or PU wont hold it with any certainty.
You could try removing it and tapping the end up to put some "fullness" back into it but I would replace it with new.

[bongovi]

Nice crack.
That item should be a new component. Its an interference fit in the head about 12.00 quid I think, Bongoshop may have them, certainly not worth risking that after everything you have done.
Silicon or PU wont hold it with any certainty.
You could try removing it and tapping the end up to put some "fullness" back into it but I would replace it with new.

I think you're right. Makes complete sense. I'll get one on order. Time for another bleed...

And yes, the crack was something. Good job it was where it was in a way, saved going looking for it in a pressure test etc.

[bongovi]

Hi all, still working through things here:

Finally got around to doing a proper bleed and test. For the bleed it got up to temp, fan on. It has blown a bit white the first few times I've tested but this morning, after yesterday's 'at temp' running, it blew *very white* and lumpy. The level in the header tank has gone down since yesterday's run under pressure, so that could just be normal expansion/reduction, but the amount of white smoke was significant.

- Could it be that running it at temp/pressure forced coolant through any small gaps?
- Could the gasket still need to melt into place more at higher temp runs?
- Am I right to stop running it until we know more?
- How can we find out more without disassembly?!


EDIT: I did end up replacing that elbow. It has stayed in place under above tests.

[bongovi]

Update:

I ran it at idle for half an hour and it cleared right up. No water being ejected nor excessive white smoke.

Ran down the street and had no power beyond 30mph so took another look and saw the air-intake pipe had popped off. Firmly reattached and took a blip around at higher revs and power felt normal, no smoke. If it smokes again from cold, and the header tank level is significantly lower, then I'll be more concerned, but at the moment it looks like it might have just been burn-off.

But if it wasn't smoking after an hour running, then it's much less likely that there's a serious crack or leak, right?

Fingers crossed we're fine and on for another great season. Our second in the Bongo, but we've already covered a half-dozen countries

[bongovi]

Quick update - more white smoke billows on starting again this morning. Started easily, first time though.

Possibly lower coolant level in HT, but not enough to tell for sure. Ran clean after initial smoking and lumpiness around 8-900rpm

Did see in another thread someone mentioned the plug rail being adjustable or something of the sort. We didn't mess with it, but it came off and went back on, of course. Perhaps there's a simple adjustment to be made?

Or there's a slight leak somewhere else? Couldn't find one around the hoses, but Um-Bongo mentioned it could be the turbo...

[Bongolia]

Personally I would run it and keep a close eye on everything. If the lump has been dumping water into the exhaust it can take a good while to clear it all out.
The lumpiness at start up may be an unrelated issue.
What rails?

[bongovi]

Personally I would run it and keep a close eye on everything. If the lump has been dumping water into the exhaust it can take a good while to clear it all out.
The lumpiness at start up may be an unrelated issue.
What rails?

Cheers. It seems to be only on start. Just did another check of coolant and test start. Slightly lower levels of coolant, but still well above 'Full' line - is it just 'settling' - has been well bled as per Youtube vid instructions. On start the white smoke lingers (filling the street) unless I run it up to 1.5-2k rpm, then it quickly clears and doesn't come back.

The glow plug rail I mentioned I got the idea when searching here for 'white smoke' posts. Seen mentions of 'unburnt fuel' and glow plug voltages varying and even someone saying how to adjust when they come on. They were cleaned (the plugs) before going back on.

So I'm looking for potential slow coolant leakage and whatever's causing the white smoke *only* on startup.

[Northern Bongolow]

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.

[Bongolia]

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?

[bongovi]

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.

[bongovi]

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.

Interesting! Yes OK, so one thing mentioned way back in this thread is that the top 'shaft' of the green NRV snapped with the brittle hose, so I glued the new hose *into* the old one, which has held till now, but was only meant to be a temp fix. Liberal amounts of the glue, so it shouldn't be leaking, but of course it's now suspect.

Having trouble finding the parts number with the local Mazda dealer, but they want my VIN num to track it down. Will supply them with that today. I know it's 13-995 on the Lush diagrams, but that's a D-code they say.

EGR valve not blanked off (yet), btw. Will look at tickover also - might have moved it in the rebuild.